Dissertations / Theses: 'Artificial muscles'

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Capps, Ryan Anthony. "Fatigue Characteristics of Pressurized Artificial Muscles." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/49702.

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Pressurized artificial muscles show promise in both standard aircraft actuation operations and in morphing structures as an alternative to currently used actuation systems due to their high power-to-weight ratio. Pressurized artificial muscles have already demonstrated the necessary force production to be utilized as an alternative actuation mechanism. In order to better understand the feasibility of using pressurized artificial muscles as a standard actuation mechanism it is necessary to determine the life cycle of pressurized artificial muscles under high pressures, loads, and strains, and how muscle geometry and materials effect the life cycle of the artificial muscle. This thesis presents a study to determine the fatigue characteristics of pressurized artificial muscles to address the issues noted above. The life cycle of the pressurized artificial muscle is examined at high internal pressures and high strains. The materials composing the pressurized artificial muscle, and the artificial muscle geometry are changed throughout the study to determine their effect on the life cycle of a pressurized artificial muscle. Finally a morphing aileron utilizing pressurized artificial muscles as the actuation mechanism is fatigue tested. Fatigue testing results show that pressurized artificial muscle fatigue life is dependent on both actuator materials and geometry. Latex rubber bladders were shown to perform better than bladders of other materials. Increasing the wall thickness of the latex bladder increased the life cycle of the pressurized artificial muscles. Additionally, casting the pressurized artificial muscle in a cylindrical polyurethane resin matrix increased the life cycle of the actuator, and increasing the diameter of this resin matrix further increased the life cycle of the actuator.
Master of Science

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Klute, Glenn K. "Artificial muscles : actuators for biorobotic systems /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/8058.

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Swamy, Amit. "Development of laboratory spine with artificial muscles." Thesis, University of Hull, 2007. http://hydra.hull.ac.uk/resources/hull:780.

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There is an increasing demand for spinal surgery and a growing number of new spinal implants and surgical procedures being offered by orthopaedic companies. However, the testing of spinal implants and spinal instrumentation is problematic, with testing in cadavers and animals becoming increasingly difficult and both having significant limitations. Thus the aim of this research is to develop an artificial laboratory spine that will have the same physical and biomechanical properties as the human spine. Validation of computer model is difficult hence an active artificial laboratory spine is being developed. A number of spinal elements have been produced and are being investigated, including an artificial intervertebral disc with different material properties to allow it to simulate different clinical conditions. The study is the first of its kind with the characteristics of the disc material that have been assessed in the laboratory, artificial muscles and spring elements and with normal physiological movements compared and validated from the reported literature. The model was used to investigate the potential of Shape Memory Alloy wires to act as artificial muscles and to control the movement of the spine. It is anticipated that the laboratory spine will have a number of other applications, in particular in the assessment of spinal instrumentation and testing. An actual geometry laboratory spine is also generated with suitable manufacturing technique for intervertebral disc, which has an accurate surface profile to fit between the two vertebral bodies above and below it, is discussed in this thesis.

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Odhner, Lael Ulam 1980. "Stochastic recruitment strategies for controlling artificial muscles." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/55257.

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Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 171-176).
This thesis presents a new architecture for controlling active material actuators inspired by biological motor recruitment. An active material is broken down into many small fibers and grouped together to form one large actuator. Each of these fibers is held in a binary state, either relaxed or contracted, using a small local controller which responds to a broadcast input signal from a central controller. The output force and displacement of the actuator is a function of the number of contracted fibers at any point in time. This architecture enables the creation of large-scale, controllable actuators from highly non-linear active materials. The key innovation enabling the central controller to coordinate the behavior of very many small identical units is to randomize the behavior of each unit. This thesis explains how a collection of active material motor units responding in a random, uncorrelated fashion to broadcast commands will exhibit a predictable response that can be stabilized with feedback control and observed using a Kalman filter. Various control strategies will be presented and discussed, including open-loop plant behavior, linear feedback, optimal control, and model-based look-ahead control. Performance metrics such as accuracy and convergence time will be analyzed using dynamic programming and other control techniques. Parallels will also be discussed between this control problem and similar control problems in the field of swarm robotics.
(cont.) The stochastic, recruitment-like actuator architecture is demonstrated in shape memory alloy actuators, each composed of 60 individual elements, having a displacement of over 20 mm and a peak force of over 100 N. Control of displacement, isometric force and stiffness are demonstrated using the observer-controller framework. Two actuators are used in an antagonistic fashion to control the stiffness and position of a 1-DOF arm joint.
by Lael Ulam Odhner.
Sc.D.

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Kingsley, Daniel A. "A COCKROACH INSPIRED ROBOT WITH ARTIFICIAL MUSCLES." Case Western Reserve University School of Graduate Studies / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=case1094932214.

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Stubbs, Laura Kate. "The development of artificial muscles using textile structures." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/the-development-of-artificial-muscles-using-textile-structures(24551192-f3a6-476d-a446-8dc2abbcb71a).html.

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The aim of this project was to investigate the use of textile structures as muscles to assist people with muscular deficiency or paralysis. Due to the average life expectancy continuing to increase, support for those needing assistance to move unaided is also increasing. The purpose of this project was to try to help a patient who would normally need assistance, to move their arm unaided. It could also help with rehabilitation of muscular injuries and increasing strength and reducing muscular fatigue of manual workers. The approach considered was to develop an extra corporal device for the upper limbs, providing the main required motions. Most devices currently available use motors and gearboxes to assist in limb movement. This study investigated a way of mimicking the contraction of biological skeletal muscles to create a motion that is as human as possible with a soft, flexible and lightweight construction. Electroactive polymers (EAPs) and pneumatic artificial muscles (PAMs) were investigated. It became clear that at present, the EAPs were unable to create the forces and speed of contraction required for this application. The use of pneumatics to create artificial muscles was developed upon. PAMs, like the McKibben muscle and the pleated pneumatic muscle mimic the natural contraction of skeletal muscle. These current PAMs were used as a basis to develop a new type of pneumatic artificial muscle in this project. A 90 mm ball-like structure was developed, produced from an air impermeable rubber coated cotton fabric. Joining three oval panels together created a 3-D spherical shape. Three of these structures were linked together, and when inflated, created an acceptable level of contraction and force. This method of producing artificial muscles created a soft, lightweight and flexible actuator with scope for different arrangements, sizes and positions of the muscle structure. The contraction process was mathematically modelled. This calculated the predicted rate and level of contraction of a 2-D muscle structure. These mathematical findings were able to be compared to the practical results, and produced similar contraction characteristics. The muscle structures were incorporated into a garment to form a type of muscle suit which could be worn to assist movement. This garment has an aluminium frame to protect the wearer's bones from stresses from the contracting muscles. This study has shown that the muscle suit developed can create movement for wearers that would normally need assistance, and also reduce muscle fatigue, which would be useful for manual workers. This is incorporated into a functional and wearable garment, which is easy to dress and more lightweight and aesthetically pleasing than current muscle suits.

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Chandrapal, Mervin. "Intelligent Assistive Knee Orthotic Device Utilizing Pneumatic Artificial Muscles." Thesis, University of Canterbury. Mechanical Engineering, 2012. http://hdl.handle.net/10092/7475.

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This thesis presents the development and experimental testing of a lower-limb exoskeleton system. The device supplies assistive torque at the knee joint to alleviate the loading at the knee, and thus reduce the muscular effort required to perform activities of daily living. The hypothesis is that the added torque would facilitate the execution of these movements by people who previously had limited mobility. Only four specific movements were studied: level-waking, gradient-walking, sit-to-stand-to-sit and ascending stairs. All three major components of the exoskeleton system, i.e. the exoskeleton actuators and actuator control system, the user intention estimation algorithm, and the mechanical construction of the exoskeleton, were investigated in this work. A leg brace was fabricated in accordance with the biomechanics of the human lower-limb. A single rotational degree of freedom at the knee and ankle joints was placed to ensure that the exoskeleton had a high kinematic compliance with the human leg. The position of the pneumatic actuators and sensors were also determined after significant deliberation. The construction of the device allowed the real-world testing of the actuator control algorithm and the user intention estimation algorithms. Pneumatic artificial muscle actuators, that have high power to weight ratio, were utilized on the exoskeleton. An adaptive fuzzy control algorithm was developed to compensate for the inherent nonlinearities in the pneumatic actuators. Experimental results confirmed the effectiveness of the adaptive controller. The user intention estimation algorithm is responsible for interpreting the user's intended movements by estimating the magnitude of the torque exerted at the knee joint. To accomplish this, the algorithm utilizes biological signals that emanate from the knee extensor and flexor muscles when they are activated. These signals combined with the knee angle data are used as inputs to the estimation algorithm. The output is the magnitude and direction of the estimated torque. This value is then scaled by an assistance ratio, which determines the intensity of the assistive torque provided to the user. The experiments conducted verify the robustness and predictability of the proposed algorithms. Finally, experimental results from the four activities of daily living, affirm that the desired movements could be performed successfully in cooperation with the exoskeleton. Furthermore, muscle activity recorded during the movements show a reduction in effort when assisted by the exoskeleton.

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Loccisano, Anthony. "Online Variable Recruitment for Pneumatic Artificial Muscles with Springs." Thesis, KTH, Mekatronik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279666.

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Pneumatic artificial muscles (PAMs) have gained attention in the realm of soft robotics for their high power to weight ratio, low manufacturing cost, low weight, and relatively high compliance. This makes them appear as a great candidate for exoskeletons. An area of recent research involves variable recruitment, the process of successively activating individual PAMs from a set to improve overall system efficiency. While a few simulation and quasi-static studies exist, very little research has investigated real time switching with a physical system. In the quasi-static studies, the buckling of non-activated PAMs has been a consistent issue. In this thesis, a set of six parallel PAMs are connected serially to individual springs to prevent non-activated PAMs from buckling during contraction. The system is run through both a batch and orderly, open loop recruitment cycle to better understand transition effects and energy consumption. It was found that the batch method uses more energy and is prone to disturbances during transitions. The serial elastic elements do prevent buckling at the cost of individual recruitment level movement capability. Recommendations for implementing the switching strategies and how to use springs are given.
Pneumatiska artificiella muskler (PAM) har fått uppmärksamhet inom området för mjuk robotik för deras höga effekt-/viktförhållande, låga tillverkningskostnader, låg vikt och relativt enkla att implementera. Detta gör dem till bra kandidater för exoskelett. Ett område inom ny forskning innefattar variabel rekrytering, en process där man successivt aktiverar enskilda PAM i ett system bestående av flera sådana, för att förbättra den totala systemeffektiviteten. Medan några simulerings- och kvasistatiska studier existerar, har väldigt lite forskning undersökt realtidskoppling med ett fysiskt system. I de kvasistatiska studierna har knäckningen av ickeaktiverade PAM: er varit en konsekvent fråga. I detta projekt är en uppsättning av sex parallella PAM-serier anslutna seriellt till enskilda fjädrar för att förhindra att icke-aktiverade PAM-skivor knäcks under sammandragning. Systemet körs genom både en "batch-" och en "orderly-"openloop-rekryteringscykel för att bättre förstå övergångseffekter och energiförbrukning. Det visade sig att batchmetoden använder mer energi och är mer benägen att påverkas av att störningar under övergångar. Fjädrarna förhindrar dock knäckning på bekostnad av individuell rekryteringsnivå. Rekommendationer för att implementera omkopplingsstrategierna och hur man använder fjädrar ges.

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Choi, Jongung. "LOCOMOTION CONTROL EXPERIMENTS IN COCKROACH ROBOT WITH ARTIFICIAL MUSCLES." Case Western Reserve University School of Graduate Studies / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=case1117207152.

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Shedd, Brian Ethan. "Multifunctional composites for data storage, artificial muscles, and microstructures." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1779690431&sid=15&Fmt=2&clientId=48051&RQT=309&VName=PQD.

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Mirvakili, Seyed M. (Seyed Mohammad). "High performance materials for artificial muscles and energy storage devices." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111738.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Artificial muscles (i.e., stimuli-responsive materials) are muscle-like materials and devices that mimic muscle's functionality (e.g., contraction, rotation, and bending) in different aspects. Some of the common performance metrics used for evaluating artificial muscles are cycle life, gravimetric/volumetric energy and/or power density, efficiency, cost, and controllability of muscle. Having a good combination of these performance metrics is very desirable and an active field of research. Many of the state-of-the-art designs are made from some exotic materials such as carbon nanotubes and metal nanowires which are not yet commercially available; here, new designs are proposed which their performance favorably compares to those of the rival materials and yet made of readily available materials. In addition to artificial muscles, designs for fast charging micro-supercapacitors are also proposed. Fast charging energy storage devices such as supercapacitors have applications in different industries ranging from automobile to telecommunication. Cellphones, for example, use fast charging micro-supercapacitors in their GSM/GPRS modulus to generate high current pulses for signal transmission purposes. The current technologies, such as tantalum/niobium oxide micro-supercapacitors are evolving around enhancing the energy and power density by increasing the specific capacitance and operating voltage. Yet, increasing the specific capacitance is still a major challenge. In this thesis, aside from discrete component geometry, flexible (e.g., yam-based) supercapacitors have various applications from flexible circuits to wearable devices. Design and fabrication of high performance supercapacitors by utilizing metal nanowires (e.g., niobium nanowires) in both forms (i.e., flexible and solid/rigid devices) are investigated as well.
by Seyed M. Mirvakili.
Ph. D.

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Tadesse, Yonas Tegegn. "Creating Human-Like Facial Expressions Utilizing Artificial Muscles and Skin." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/30159.

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Mimicking facial structures for a robotic head requires integration of multiple structural and mechanical parameters, design, synthesis and control of muscle actuation, architecture of the linkages between actuation points within skin, and implementation of the deformation matrix with respect to global skull coordinates. In this dissertation, humanoid faces were designed and fabricated to investigate all the parameters mentioned above. A prototype face and neck was developed using servo motors and extensively characterized. In this prototype, a neck mechanism was designed using a four bar mechanism to achieve nodding and turning motions. The modular neck prototype simplifies the assembly and statically in equilibrium and hence demands less torque from the cost-effective RC servo motor. The mechanism was critically investigated for dynamic performance and it was found out that RC servo based robotic head requires a PD external controller to overcome inherent overshoot. The servo based robotic head was analyzed for design and control of anchor, architecture of linkages between actuation points within skin, and deformation matrix with respect to global coordinate for creating specific expressions. A functional relationship between deformation vector of facial control points and actuator parameter, skin elasticity and angular position of actuator was derived. The developed analysis method is applicable to any rotary actuator technology utilized for facial expressions and takes into account the skin stiffness. The artificial skin materials for facial expression were synthesized using platinum-cured silicone elastomeric material (Reynolds Advanced Materials Inc.) with base consisting of mainly polyorganosiloxanes, amorphous silica and platinum-siloxane complex compounds. Systematic incorporation of porosity in this material was found to lower the force required to deform the skin in the axial direction. The performance of the servo motor based face was quite realistic but it suffers from the drawback of large power consumption, bulky, heavy, and limited functionality. Thus, significant effort was made in developing a Biometal fiber and Flexinol shape memory alloy actuator (SMA) based biped mountable baby head facial structure which resembles the form and functionality of a human being. SMAs were embedded inside a skull and connected to elastomeric skin at control points. An engineered architecture of skull was fabricated that incorporates all the muscles with their 35 routine pulleys, two fire wire CMOS cameras that serve as eyes, and a battery powered microcontroller base driving circuit within the total dimensions of 140 mm x 90 mm x 110 mm. The driving circuit was designed such that it can be easily integrated with biped and processed in real-time. The humanoid face with 12DOF was mounted on the body of DARwIn (Dynamic Anthropomorphic Robot with Intelligence) robot which has 21 DOF resulting in a total of 33 DOF system. Characterization results on the face and associated design issues are described that provide pathways for developing human-like facial anatomy. Numerical simulation using Simulink was conducted to assess the performance of a prototypic robotic face mainly focusing on jaw movement. A graphical method “Graphical Facial Expression Analysis and Design (GFEAD)” was developed that can be used to allocate the sinking points on robotic head. The method assumes that the origin of the action units are known prior and the underlying criterion in the design of faces being deformation of a soft elastomeric skin through tension in anchoring wires attached on one end to the sinking point and on the other to the actuator. Experimental characterization on a prototyping humanoid face was performed to validate the model and demonstrate the applicability on a generic platform. During characterization of the SMA based face, it was found that the currently available artificial muscle technologies do not meet the entire requirement for being embedded in the skin and provide the required strain rate, maximum strain, blocking force, response time and energy density. Thus an effort was made to develop conducting polymer based artificial muscles which can meet the metrics of human muscle. Composite stripe and zigzag actuators consisting of a sandwich structure polypyrrole /poly(vinylidene difluoride) (PPy/PVDF) were synthesized using potentiodynamic film growth on gold electrodes. The synthesis was done from an aqueous solution containing tetrabutylammonium Perchlorate (TBAP) and pyrrole by polymerization at room temperature. For depositing thin PPy films and thereby minimizing the response time, an experimental optimization of the deposition conditions was performed. The number of current-potential (potentiodynamic) growth cycles and the thickness of the deposited PPy film were highly correlated in the initial stages of polymer film growth. Strip actuator of size 11 x 5 mm2 with 63μM exhibited a deflection of 3mm under 1V DC voltage and 2mm deflection under 8V AC voltage at 0.5 Hz. It was found that three-segment zigzag actuator of segment length 15x2.5mm and thickness 63μM amplifies the displacement by 1.5 times. A study was also conducted on the synthesis and characterization of thick and thin film polypyrrole (PPy) – metal composite actuators. The fabrication method consisted of three steps based upon the approach proposed by Ding et al.: (i) winding the conductive spiral structure around the platinum (Pt)-wire core, (ii) deposition of PPy film on the Pt-wire core, and (iii) removal of the Pt-wire core. This approach yielded good performance from the synthesized actuators, but was complex to implement due to the difficulty in implementing the third step. To overcome the problem of mechanical damage occurring during withdrawal of Pt-wire, the core was replaced with a dispensable gold coated polylactide fiber that could be dissolved at the end of deposition step. Experimental results indicate that thin film actuators perform better in terms of response time and blocking force. A unique muscle-like structure with smoothly varying cross-section was grown by combining layer by layer deposition with changes in position and orientation of the counter electrode in reference to the working electrode. Synthesis of polypyrrole–metal coil was conducted in aqueous solution containing 0.25 M Pyrrole, 0.10 M TBAP and 0.50 M KCl. The actuator consisted of a single layer of platinum winding on a core substrate. Electrochemical characterization for free strain and blocking stress was conducted 0.1 M TBAP solution and a 6% free strain was obtained at an applied potential of 6V DC after 80 s stimulation time. The blocking stress 18 kPa was estimated by extrapolating the strain magnitude on stress-strain diagram. For axial type actuator with coil winding, a generalized governing equation for the electrochemical stress generated from polypyrrole–metal coil which accommodates the effect of magnetic field due to winding was proposed and numerically studied. It was considered as insightful modeling.
Ph. D.

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Mudigonda, Ashwin. "Static and Dynamic Characterization of Ionic Polymer Metal Composites - 'Artificial Muscles'." Ohio : Ohio University, 2006. http://www.ohiolink.edu/etd/view.cgi?ohiou1142538201.

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ASSIS, PEDRO FERREIRA DA COSTA BLOIS DE. "CHARACTERIZATION OF ACTUATORS BASED ON POLYMERIC ARTIFICIAL MUSCLES WITH CAPACITIVE EFFECT." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=11510@1.

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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
É notória a necessidade de encontrar novas tecnologias para atuação de sistemas robóticos tão eficazes quanto a do músculo natural. Os atuadores tradicionais possuem grande agilidade e força quando comparados aos músculos naturais, mas suas dimensões e peso são elevados em relação à força que são capazes de exercer, e demandam muita energia para cumprirem suas tarefas. Manipuladores robóticos menores e mais baratos poderiam existir se pudessem utilizar músculos naturais para impulsioná-los. Ao mesmo tempo, as indústrias gastariam menos com os custos envolvidos em energia e compra desses manipuladores. Este trabalho estuda o comportamento de músculos artificiais baseados no polímero acrílico VHB4905, através da construção de uma bancada de teste com sensor de força, incluindo especificação de todos os equipamentos e o desenvolvimento de circuitos de alta tensão (até 10kV) para acioná-los. Durante o desenvolvimento e implementação do circuito foram encontrados problemas intrínsecos à manipulação de tensões da ordem de vários kV. Esses problemas foram apontados e soluções satisfatórias foram implementadas, de forma a tornar os experimentos possíveis. Modelos matemáticos de algumas das principais configurações possíveis para atuadores foram desenvolvidos. Os modelos desenvolvidos para uma das configurações típicas foram comparados com resultados experimentais com um erro máximo absoluto de 1% (26,7mN) do valor real. Experimentos em atuadores de molduras fixas foram feitos com resultados de 223% de deformação da região ativa, com desempenho muito superior ao dos músculos naturais. A partir de um dos modelos desenvolvidos, implementou-se um controlador PID compensado que gerou melhores resultados a entradas em degrau que o PID padrão, o qual não leva em consideração a não linearidade e a alta sensibilidade do atuador quando submetido a tensões próximas da tensão de quebra do dielétrico. A eficácia da técnica de controle proposta foi comprovada experimentalmente.
It is well known the needs of finding new technologies for robotic systems actuations, with the same efficiency of the natural muscles. The common actuators have better agility and force when compared to natural muscles, but the dimensions and weight are bigger and for that the demand of energy necessary for the actuation is higher. Smaller and cheaper robot manipulators could exist if they were able to use natural muscles to drive them. At the same time, industries would spend less money with energy and manipulators. This work studies the behavior of artificial muscles based on dielectric elastomers (VHB4905) through the development of a test bench with force transducer, including the specification of all the equipments and the development of a high voltage circuit (10kV maximum). During the development and implementation of the circuit, problems inherent to high voltage manipulation were found. Those problems were shown and tolerable solutions were taken, so that the experiments were feasible. Mathematic models of some of the main configurations for actuators were developed. One of those models (from a typical configuration) was compared with experimental results with a maximum absolute error of 1% (26.7mN) of the real value. Experiments with fixed frame actuators were made with 223% of strain, showing a much higher performance compared to natural muscles. With one of the mathematic models, a PID controller with adjustable gains was developed and presented better results, for a step response, when compared to a standard PID controller. This last one do not take into account the non-linearities and for that it behaviors with great sensibility when subjected to high voltages (close to dielectric breakdown). The effectiveness of the proposed control technique was proved experimentally.

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Price, Aaron David. "Biologically inspired dexterous robot hand actuated by smart material based artificial muscles." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27409.

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Modern externally powered upper-body prostheses are conventionally actuated by electric servomotors. Although these motors achieve reasonable kinematic performance, they are voluminous and heavy. Deterring factors such as these lead to a substantial proportion of upper extremity amputees avoiding the use of their prostheses. Therefore, it is apparent that there exists a need for functional prosthetic devices that are compact and light-weight. The realization of such a device requires an alternative actuation technology, and biological inspiration suggests that tendon based systems are advantageous. Shape memory alloys are a type of smart material that exhibit an actuation mechanism resembling the biological equivalent. As such, shape memory alloy enabled devices promise to be of major importance in the future of dexterous robotics, and to prosthetics in particular. This thesis investigates the issues surrounding the practical application of shape memory alloys as artificial muscles in a three fingered robot hand. First the function of the human hand and the kinematic requirements for manipulation are reviewed. An overview of artificial hands is provided, followed by a discussion on shape memory alloys focused on the unique phenomena of the shape memory effect. Second, the forward and inverse kinematics of the artificial finger are established in order to relate the desired finger tip contact point to the required joint angles. This is followed by the design of the requisite instrumentation and control systems. Due to the highly nonlinear nature of both the SMA and the robot hand, alternative control approaches such as neural networks are reviewed. Finally, a large-strain SMA actuator is proposed and the concepts explored herein are applied to the design, manufacture, and evaluation of an SMA actuated robotic hand.

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RAMOS, JOAO LUIZ ALMEIDA DE SOUZA. "TORQUE CONTROL OF AN EXOSKELETON ACTUATED BY PNEUMATIC ARTIFICIAL MUSCLES USING ELECTROMYOGRAPHIC SIGNALS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2013. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=22293@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
A robótica aplicada à reabilitação e amplificação humana está em uma fase iminente de se tornar parte de nossa vida diária. A justaposição da capacidade de controle humana e o poder mecânico desenvolvido pelas máquinas oferecem uma promissora solução para auxílio físico e de amplificação humana. O presente trabalho apresenta um exoesqueleto ativo para membros superiores controlado por uma alternativa e simples Interface Homem-Máquina (HMI) que utiliza o Modelo Muscular de Hill para aumentar a força e resistência mecânica do usuário. Músculos Pneumáticos Artificiais (PAM) são utilizados como atuadores por sua alta razão entre potência e peso e atuam o sistema através de um esquema com cabos de aço. Algoritmos Genéticos (GA) aproximam localmente os parâmetros do modelo matemático do atuador e o modelo fisiológico do músculo, que utiliza sinais eletromiográficos superficiais (sEMG) para estimar o torque na articulação do exoesqueleto. A metodologia proposta oferece três vantagens principais: (i) reduz o número de eletrodos necessários para monitorar a atividade muscular, (ii) elimina a necessidade de transdutores de força ou pressão entre o exoesqueleto e o usuário ou o ambiente e (iii) reduz o custo de processamento em tempo-real, necessário para implementações de sistemas embarcados. O exoesqueleto é restrito ao membro superior direito e a estratégia de controle é avaliada verificando o desempenho do usuário ao manipular uma carga de 3.1kg estática e dinamicamente com e sem o auxílio do equipamento assistivo.
Robotics for rehabilitation and human amplification is imminent to become part of our daily life. The juxtaposition of human control capability and machine mechanical power offers a promising solution for human assistance and physical enhancement. This work presents an upper limb active exoskeleton controlled by an alternative and simple Human-Machine Interface (HMI) that uses a Hill Muscle Model for strength and endurance amplification. Pneumatic Artificial Muscles (PAM) are used as actuators for its high power-to-weight ratio and to drive the system through a cable arrangement. Genetic Algorithms (GA) approach locally optimizes the model parameters for the actuator mathematical model and the physiologic muscle model that uses the surface electromyography (sEMG) to estimate the exoskeleton joint torque. The proposed methodology offers three main advantages: (i) it reduces the number of electrodes needed to monitor the muscles, (ii) it eliminates the need for user force or pressure sensoring, and (iii) it reduces the real-time processing effort which is necessary for embedded implementation and portability. The exoskeleton is restricted to the right upper limb and the control methodology is validated evaluating the user performance while dynamically and statically handling a 3.1kg payload with and without the aid of the assistive device.

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Obiajulu, Steven (Steven C. ). "Soft pneumatic artificial muscles with low threshold pressures for a cardiac compression device." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/83730.

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Thesis (S.B.)--Massachusetts Institute of Technology, Department of Mechanical Engineering, 2013.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 45-47).
In this paper, I present the design, fabrication and characterization of fully soft pneumatic artificial muscles (PAMs) with low threshold pressures that are intended for direct cardiac compression (DCC). McKibben type PAMs typically have a threshold pressure of at least lOOkPa and require rigid end fittings which may damage soft tissue and cause local stress concentrations, and thus failure points in the actuator. The actuator design I present is a variant on the McKibben PAM with the following key differences: the nylon mesh is embedded in the elastomeric tube, and closure of the end of the tube is achieved without rigid ends. The actuators were tested to investigate the effects of mesh geometry and elastomer material on force output, contraction, and rise time. Lower initial braid angles and softer elastomer materials provided the best force, contraction, and rise times; Up to 50N of force, 24% contraction, and response times of 0.05s were achieved at 100kPa. The actuators exhibited low threshold pressures (<5kPa) and high rupture pressures (138kPa - 720kPa) which suggest safe operation for the DCC application. These results demonstrate that the actuators can achieve forces, displacements, and rise times suitable to assist with cardiac function.
by Steven Obiajulu.
S.B.

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Sundar, Kartik. "The importance of muscle mechanics during movement." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28137.

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Thesis (M. S.)--Biomedical Engineering, Georgia Institute of Technology, 2009.
Committee Chair: DeWeerth, Stephen P.; Committee Co-Chair: Ting, Lena H.; Committee Member: Burkholder, Thomas J.; Committee Member: Nichols, T. Richard; Committee Member: Tresch, Matthew C.

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Bambeck, Timothy J. "A computer controlled data acquisition and control system for a shape-memory alloy artificial muscle." Ohio : Ohio University, 1993. http://www.ohiolink.edu/etd/view.cgi?ohiou1174935244.

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LOPEZ, ROCEM POL JIMENEZ. "DEVELOPMENT OF THREE-DIMENSIONAL ACTUATORS BASED ON DIELECTRIC ARTIFICIAL MUSCLES OF ONE OR MULTIPLE LAYERS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2009. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=14603@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO
Músculos artificiais são versáteis para o projeto de atuadores pois, assim como os músculos naturais, podem ter pequenas dimensões ou serem agrupados para alcançar maiores dimensões. A capacidade do músculo de permitir a construção de atuadores sem partes móveis permite uma grande economia de energia, evitando atritos por deslizamento, menor desgaste, e baixos ruídos.Músculos artificiais são usados para desenvolver atuadores contínuos ou binários, utilizando diversos tipos de configurações para aproveitar ao máximo as vantagens que oferecem estes materiais. Músculos artificiais eletrostrictivos, acionados por altas tensões, já estão sendo utilizados em aplicações comerciais. Circuitos eletrônicos estão sendo projetados para trabalhar com altas tensões elétricas e interagir com estes tipos de músculos. Diversos tipos de material estão sendo avaliados para a implementação destes músculos.Este trabalho visa desenvolver um atuador de configuração cilíndrica de acionamento elétrico, por efeito capacitivo. O atuador é acionado por 3 músculos artificiais em configuração paralela, construídos a partir do elastômero acrílico VHB4905, o qual possui características visco-elásticas e baixo custo de produção. São analisados distintos modelos constitutivos dos músculos, baseados em molas e amortecedores em série e em paralelo.São desenvolvidos métodos de calibragem para calcular os parâmetros dos modelos matemáticos dos músculos a partir de dados obtidos em laboratório. Um método de medição baseado em processamento de imagens e teoria de visão estéreo, desenvolvido especificamente para este trabalho, permite que a posição da extremidade do atuador seja medida de forma não-invasiva, sem interferir em seu movimento, e sem a necessidade de colocar sensores ou instrumentos de medição. Os resultados mostram que os modelos matemáticos são eficientes para descrever o comportamento do atuador.
Artificial muscles are versatile for the actuator projects, because, as well as the natural muscles, they can have small dimensions or they are grouped to obtain big dimensions. Muscle capacity to allow construction of actuators without movable parts allows great economy of energy, avoiding attritions for sliding, lessening waste, and reducing noise.Artificial muscles are used to develop continuous or binary actuators, using different types of configurations to take advantage to the benefit that offer these materials. Eletrostrictive artificial muscles, worked by high tensions, are already being used in commercial applications. Electronic circuits are being projected to work with high electric tensions and to interact with these types of muscles. Many types of materials are being evaluated for the implementation of these muscles.This work looks for to develop a cylindrical configuration actuator of electric activation, for capacitive effect. The actuator is activated by 3 artificial muscles in parallel configuration, built starting from the acrylic elastomer VHB4905, which possesses viscouselastic characteristics and low production cost. Different models of the muscles are analyzed, based on springs and shock absorbers in series and parallel.Calibrate methods are developed to calculate parameters of the mathematical models of the muscles starting from data obtained at laboratory. Measurement method based on processing of images and theory of stereo vision, specifically developed for this work, allows no-invasive measurement of the actuator’s extremity, without interfering in actuator’s movement, and without the need to put sensor or measurement instruments. The results show that mathematical models are efficient to describe the behavior of the actuator.

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21

Simaite, Aiva. "Development of ionic electroactive actuators with improved interfacial adhesion : towards the fabrication of inkjet printable artificial muscles." Thesis, Toulouse, INSA, 2015. http://www.theses.fr/2015ISAT0043/document.

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Les actionneurs à base de polymères électroactifs ioniques constituent une alternative prometteuse par rapport aux actionneurs conventionnels, en particulier lorsqu’une réponse comparable à celle d’un muscle naturel est recherché. Parmi eux, les actionneurs à base de polymères conducteurs constituent une voie prometteuse pour des applications biomédicale où la biocompatibilité, la compacité et un positionnement précis sont requis. Néanmoins, l’essor de dispositifs fonctionnels est fortement ralenti en raison de la faible efficacité d’actionnement et de la rapide dégradation des performances de ce type d’actionneurs. L’absence de rétroaction sur la force ou sur la position est également un autre aspect limitant le développement de cette approche. L’objectif de cette thèse est de proposer une technique de fabrication à grande échelle pour l’élaboration d’actionneurs à base de polymères électroactifs ioniques et permettant également l’intégration de capteurs pour un contrôle rétroactif. L’impression par jet d’encre est une technologie clé pour le dépôt de polymères et une des plus alternatives les plus prometteuses pour la production d’actionneurs à base de polymères conducteurs. Cependant, la fabrication d’actionneurs par technique jet d’encre n’est pas encore totalement maîtrisée à cause des propriétés rhéologiques des solutions de polymères conducteurs qui rendent difficile le contrôle de l’éjection de gouttes mais également en raison de la nature complexe des interactions entre la solution et l’échantillon qui peut conduire à une faible adhésion et un mauvais contrôle de l’infiltration de l’encre. Pour optimiser cette méthode de fabrication, des membranes hybrides contenant des ions ont été développées. Le greffage d’un monomère hydrophile par plasma argon avec un dépôt contrôlé en profondeur a été utilisé pour obtenir des membranes en polyfluorure de vinylidène (PVDF) avec des surfaces hydrophiles tout en conservant une zone centrale hydrophobe. Ces membranes hybrides ont permis d’obtenir, par dépôt de gouttes, des actionneurs de morphologies très variées à base de polymères conducteurs. En outre, la durée de vie d’actionneurs obtenus avec une solution conductrice de poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) a été sensiblement augmentée avec des déformations de plus de 0.6% sans qu’aucun signe de délamination ne soit perceptible. Enfin, la nature complexe des mécanismes physico-chimiques à l’origine des interactions entre le film polymère et la membrane poreuse a été mieux appréhendée durant ce travail. Les conditions nécessaires pour assurer une forte adhésion et les effets conduisant à un mauvais contrôle de l’infiltration ont été partiellement identifiés. Ces résultats ont permis de définir les paramètres clés concernant la préparation de la membrane et la composition de la solution polymère. En associant l’ensemble de ces résultats avec les exigences liées à l’utilisation de l’impression de solutions par jet d’encre, nous avons réalisé, en utilisant cette technique de dépôt, les premiers actionneurs ioniques à base de PEDOT:PSS
Onic electroactive polymer based artificial muscles are promising alternative to traditional actuators, especially where compliant muscle-like response is desirable. Among them, conducting polymer actuators (CPAs) are most promising for biomedical applications, where biocompatibility, compactness and accurate positioning is essential. Nevertheless, development of applicable devices is hold down by their low efficiency and fast performance deterioration. The absence of a tactile, force or position feed-back is another feature limiting the development of functional devices. The goal of this thesis is to develop a fabrication technique for conducting polymer based actuators that could be up-scalable and enable facile integration of sensory feedback. Inkjet printing is key technology in the field of defined polymer deposition as well as in fabrication of strain sensors. It is also one of the most promising alternatives to prevalent fabrication of conducting polymer actuators. Nevertheless, inkjet printed actuators were not yet realized due to rheological properties of conducting polymer solutions that challenge jetting and the complex solution - membrane interactions, that lead to poor adhesion or uncontrolled infiltration. In order to enable this fabrication method, hybrid ion-storing membranes were developed. Argon plasma induced grafting-to of hydrophilic macromonomer with limited-indepth deposition was used to obtain polyvinylidene fluoride (PVDF) membranes with hydrophilic upper surfaces and hydrophobic centre. Functionalized PVDF membranes were shown to withhold good adhesion to the conducting polymer films and preserve electrically insulating layer in between them. Hybrid membranes were demonstrated to be advantageous in fabrication of CPAs by drop casting and enable production of actuators with various morphologies. Furthermore, fabricated poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) based actuators demonstrated long lifetime with no signs of delamination as well as large strain of more than 0.6%. In addition, the complex nature of the physico-chemical mechanisms of the interactions between the polymer film and the porous membrane was better understood during this work. The conditions necessary in order to ensure strong adhesion as well as circumstances leading to uncontrolled infiltration were partially identified. These were used to set up limits to membrane preparation and polymer solution composition. Combining obtained knowledge with known requirements for inkjet printable solutions lead to the realization of the first inkjet printed PEDOT:PSS based ionic actuators

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22

Yang, Hee Doo. "Modeling and Analysis of a Novel Pneumatic Artificial Muscle and Pneumatic Arm Exoskeleton." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78284.

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The soft robotics field is developing rapidly and is poised to have a wide impact in a variety of applications. Soft robots have intrinsic compliance, offering a number of benefits as compared to traditional rigid robots. Compliance can provide compatibility with biological systems such as the human body and can provide some benefits for human safety and control. Further research into soft robots can be advanced by further development of pneumatic actuators. Pneumatic actuators are a good fit for exoskeleton robots because of their light weight, small size, and flexible materials. This is because a wearable robot should be human friendly, therefore, it should be light weight, slim, powerful, and simple. In this paper, a novel pneumatic artificial muscle using soft materials including integrated electronics for wearable exoskeletons is proposed. We describe the design, fabrication, and evaluation of the actuator, as well as the manufacturing process used to create it. Compared to traditional pneumatic muscle actuators such as the McKibben actuator and new soft actuators that were recently proposed, the novel actuator overcomes shortcomings of prior work. This is due to the actuator's very high contraction ratio that can be controlled by the manufacturing process. In this paper, we describe the design, fabrication, and evaluation of a novel pneumatic actuator that can accommodate integrated electronics for displacement and pressure measurements used for data analysis and control. The desired performance characteristics for the actuator were 100 ~ 400N at between 35kPa and 105kPa, and upon testing we found almost 120 ~ 300N which confirms that these actuators may be suitable in soft exoskeleton applications with power requirements comparable to rigid exoskeletons. Furthermore, a novel soft pneumatic elbow exoskeleton based on the pneumatic actuator concept and manufacturing process is presented. Each structure is designed and manufactured with all fabric. The distally-worn structure is only 300g, which is light weight for an arm exoskeleton, and the design is simple, leading to a low materials cost.
Master of Science

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23

Davidson, S. Naomi (Sarah Naomi). "Development of conducting polymer based biomimetic muscles and fabrication techniques for an artificial pectoral fish fin." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32362.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.
Includes bibliographical references.
Fish possess a greater degree of agility, maneuverability, and energy efficiency over current underwater vehicles constructed by engineers. Kinematics studies show that a high degree of three-dimensional control of multiple active surfaces distributed around an undersea vehicle's center of mass is critical to achieve fish-like superior performance. However, current technology has yet to exploit the use of actively controlled surfaces for underwater locomotion. Major obstacles limiting effectively achieving designs capable of active deformations in multiple degrees of freedom lie in the complexity associated with traditional actuators and their associated manufacturing techniques. Conducting polymers possess numerous desirable physical and active properties which make it possible to grow rather than build artificial muscles for an articulated device. Their potential for co-fabrication make it possible to implement simpler more integrated designs as they have been shown to provide all the basic elements required for a Biomimetic robot including: force sensors (analogous to the Golgi organs in tendons), strain sensors (like muscle spindles), structural elements (such as bones, joints, and webbing), and actuators (akin to muscle). Rapid prototyping and molding techniques were used to begin the development of a co-fabrication process for a pectoral fin which will be made from and actuated by conducting polymers. Conducting polymer actuators provide the necessary structural flexibility while exceeding the 800 kN/m² force requirements typical of fish muscle by 40 fold.
(cont.) Maximum speed requirements of 2.1 Hz for swimming speeds up to 1.1 TLs⁻¹ (total body length/s) are attainable at the strains required for metrics of the current artificial fin design.
by S. Naomi Davidson.
S.M.

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24

Wu, Yongxian. "Experimental characterization and modeling of ionic polymer-metal composites as biomimetic actuators, sensors, and artificial muscles /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2005. http://wwwlib.umi.com/cr/ucsd/fullcit?p3167842.

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Gomes, Cristiane Faccio. "Avaliação eletromiográfica dos músculos masseter, temporal e bucinador de lactentes em situação de aleitamento natural e artificial /." Botucatu : [s.n.], 2005. http://hdl.handle.net/11449/104692.

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Orientador: Ercília Maria Caroni Trezza
Banca: Emílio Cezar Mamede Murade
Banca: Luciana Tavares Sebastião
Banca: Maria Teresa Cera Sanches
Resumo: Considerando as especificidades da eletromiografia com eletrodos de captação de superfície na avaliação da atividade muscular e a escassez de trabalhos que demonstrem as diferenças entre as atividades dos músculos responsáveis pela sucção no aleitamento materno, aleitamento por mamadeira e por copo em lactentes, este trabalho tem como objetivos: a) estabelecer um padrão da participação dos músculos masseter, temporal e bucinador no grupo de aleitamento materno com lactentes a termo e sadios e b) mensurar e comparar a atividade muscular dos músculos masseter, temporal e bucinador quando em aleitamento materno, aleitamento por mamadeira e por copo, no que se refere à amplitude e média de contração. Para tanto utiliza-se o estudo transversal, com participação de sessenta lactentes nascidos a termo e sem intercorrências, entre dois e três meses de idade, divididos em três grupos: 1) vinte lactentes em aleitamento materno exclusivo, 2) vinte lactentes em aleitamento misto com uso de mamadeira e 3) vinte lactentes em aleitamento materno exclusivo com uso de copo. Foi realizada eletromiografia com eletrodos de captação de superfície durante a alimentação do lactente. O teste estatístico utilizado foi Krushal-Wallis complementado com as comparações múltiplas entre pares de grupos e todas as discussões foram realizadas no nível de 5% de significância. Verifica-se, inicialmente, que na padronização do grupo de aleitamento materno obtém-se maior participação do músculo temporal, seguido do masseter, ficando o bucinador com menores valores tanto no que se refere à amplitude quanto à média de contração muscular, revelando que, de acordo com a literatura, no aleitamento materno o lactente apresenta condições para o adequado crescimento das estruturas e desenvolvimento das funções... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Considering the specificities of electromyography with surface electrodes in evaluation of muscular activity, and the scarcity of studies that would demonstrate the differences between the activities of the muscles responsible for sucking in breastfeeding, bottle feeding and cup feeding in infants, this work aimed to: a) establish a standard of participation of the masseter, temporal and buccinator muscles in the breastfeeding group with infants at term and healthy and b) measure and compare the muscular activity of masseter, temporal and buccinator muscles under breastfeeding, bottle feeding and cup feeding with reference to cycles of sucking and amplitude. For this a transversal study was utilized with participation of sixty newborn infants at term and without complications, aged between two and three months, divided into three groups: 1) twenty lactents under exclusive breastfeeding; 2) twenty lactents under breast and bottle fed and 3) twenty lactents in exclusive breastfeeding with cup use. Electromyography was realized with surface electrodes during infant feeding. The statistical test utilized was Krushal-Wallis complemented with multiple comparisons between pairs of groups and the level of significance of all discussions was 5%. It was verified that, initially, in standard of the breastfeeding group was obtained the greatest participation of the temporal muscle, followed by the masseter and with the buccinator presenting the smallest values for amplitude as much as mean muscular contraction, revealing that, in agreement with the literature, in breastfeeding the lactent presents adequate growth of structures and development of Stomatognathic System. From measuring and comparing results of muscular activity of muscles... (Complete abstract click electronic access below)
Doutor

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26

Gomes, Cristiane Faccio [UNESP]. "Avaliação eletromiográfica dos músculos masseter, temporal e bucinador de lactentes em situação de aleitamento natural e artificial." Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/104692.

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Made available in DSpace on 2014-06-11T19:33:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-11-11Bitstream added on 2014-06-13T20:05:21Z : No. of bitstreams: 1 gomes_cf_dr_botfm.pdf: 1459850 bytes, checksum: 6e9f04ec90f0f2e682fd2995a89c2891 (MD5)
Considerando as especificidades da eletromiografia com eletrodos de captação de superfície na avaliação da atividade muscular e a escassez de trabalhos que demonstrem as diferenças entre as atividades dos músculos responsáveis pela sucção no aleitamento materno, aleitamento por mamadeira e por copo em lactentes, este trabalho tem como objetivos: a) estabelecer um padrão da participação dos músculos masseter, temporal e bucinador no grupo de aleitamento materno com lactentes a termo e sadios e b) mensurar e comparar a atividade muscular dos músculos masseter, temporal e bucinador quando em aleitamento materno, aleitamento por mamadeira e por copo, no que se refere à amplitude e média de contração. Para tanto utiliza-se o estudo transversal, com participação de sessenta lactentes nascidos a termo e sem intercorrências, entre dois e três meses de idade, divididos em três grupos: 1) vinte lactentes em aleitamento materno exclusivo, 2) vinte lactentes em aleitamento misto com uso de mamadeira e 3) vinte lactentes em aleitamento materno exclusivo com uso de copo. Foi realizada eletromiografia com eletrodos de captação de superfície durante a alimentação do lactente. O teste estatístico utilizado foi Krushal-Wallis complementado com as comparações múltiplas entre pares de grupos e todas as discussões foram realizadas no nível de 5% de significância. Verifica-se, inicialmente, que na padronização do grupo de aleitamento materno obtém-se maior participação do músculo temporal, seguido do masseter, ficando o bucinador com menores valores tanto no que se refere à amplitude quanto à média de contração muscular, revelando que, de acordo com a literatura, no aleitamento materno o lactente apresenta condições para o adequado crescimento das estruturas e desenvolvimento das funções...
Considering the specificities of electromyography with surface electrodes in evaluation of muscular activity, and the scarcity of studies that would demonstrate the differences between the activities of the muscles responsible for sucking in breastfeeding, bottle feeding and cup feeding in infants, this work aimed to: a) establish a standard of participation of the masseter, temporal and buccinator muscles in the breastfeeding group with infants at term and healthy and b) measure and compare the muscular activity of masseter, temporal and buccinator muscles under breastfeeding, bottle feeding and cup feeding with reference to cycles of sucking and amplitude. For this a transversal study was utilized with participation of sixty newborn infants at term and without complications, aged between two and three months, divided into three groups: 1) twenty lactents under exclusive breastfeeding; 2) twenty lactents under breast and bottle fed and 3) twenty lactents in exclusive breastfeeding with cup use. Electromyography was realized with surface electrodes during infant feeding. The statistical test utilized was Krushal-Wallis complemented with multiple comparisons between pairs of groups and the level of significance of all discussions was 5%. It was verified that, initially, in standard of the breastfeeding group was obtained the greatest participation of the temporal muscle, followed by the masseter and with the buccinator presenting the smallest values for amplitude as much as mean muscular contraction, revealing that, in agreement with the literature, in breastfeeding the lactent presents adequate growth of structures and development of Stomatognathic System. From measuring and comparing results of muscular activity of muscles... (Complete abstract click electronic access below)

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27

Ramirez, Arias José Luis. "Development of an artificial muscle for a soft robotic hand prosthesis." Thesis, Paris 10, 2016. http://www.theses.fr/2016PA100190/document.

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Le thème central de cette thèse est la conception d’actionneurs doux à partir de matériaux intelligents et d’une prothèse de main robotique souple. Notre approche prends en compte les différents points qui peuvent influer sur le développement d’une stratégie d’actionnement ou d’un muscle artificiel : i) Les mécanismes et la fonctionnalité de la main humaine afin d’identifier les exigences fonctionnelles pour une prothèse de main robotique en matière de préhension. ii) L’analyse et l’amélioration des mécanismes de la main robotique pour intégrer un comportement souple dans la prothèse. iii) L’évaluation expérimentale de la prothèse de main robotique afin d’identifier les spécifications du système d’actionnement nécessaire au fonctionnement cinématique et dynamique du robot. iv) Le développement et la modélisation d’une stratégie d’actionnement utilisant des matériaux intelligents.Ces points sont abordés successivement dans les 4 chapitres de cette thèse1. Analyse du mouvement de la main humaine pour l’identification des exigences technologiques pour la prothèse de main robotique.2. Conception et modélisation de la prothèse de main robotique à comportement souple.3. Evaluation mécatronique de la prothèse de main.4. Conception d’un muscle artificiel basé sur des matériaux intelligents
In the field of robotic hand prosthesis, the use of smart and soft materials is helpful in improving flexibility, usability, and adaptability of the robots, which simplify daily living activities of prosthesis users. However, regarding the smart materials for artificial muscles, technologies are considered to be far from implementation in anthropomorphic robotic hands. Therefore, the target of this thesis dissertation is to reduce the gap between smart material technologies and robotic hand prosthesis. Five central axes address the problem: i)identification of useful grasping gestures and reformulation of the robotic hand mechanism, ii) analysis of human muscle behavior to mimic human grasping capabilities, iii) modeling robot using the hybrid model DHKK-SRQ for the kinematics and the virtual works principle for dynamics, iv) definition of actuation requirements considering the synergy between prehension conditions and robot mechanism, and v) development of a smart material based actuation system.This topics are addressed in four chapters:1. Human hand movement analysis toward the hand prosthesis requirements2. Design and modeling of the soft robotic hand ProMain-I3. Mechatronic assessment of Prosthetic hand4. Development of an artificial muscle based on smart materials

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Pan, Min, Zhe Hao, Chenggang Yuan, and Andrew Plummer. "Development and control of smart pneumatic mckibben muscles for soft robots." Technische Universität Dresden, 2020. https://tud.qucosa.de/id/qucosa%3A71262.

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Animals exploit soft structures to move smoothly and effectively in complex natural environments. These capabilities have inspired robotic engineers to incorporate soft actuating technologies into their designs. Developing soft muscle-like actuation technology is one of the grand challenges in the creation of soft-body robots that can move, deform their body, and modulate body stiffness. This paper presents the development of smart pneumatic McKibben muscles woven and reinforced by using conductive insulated wires to equip the muscles with an inherent sensing capability, in which the deformation of the muscles can be effectively measured by calculating the change of wire inductance. Sensing performance of a variety of weaving angles is investigated. The ideal McKibben muscle models are used for analysing muscle performance and sensing accuracy. The experimental results show that the contraction of the muscles is proportional to the measured change of inductance. This relationship is applied to a PID control system to control the contraction of smart muscles in simulation, and good control performance is achieved. The creation of smart muscles with an inherent sensing capability and a good controllability is promising for operation of future soft robots.

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Závodný, Tomáš. "Návrh umělého svalu pro oblast robotiky." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-382411.

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The diploma thesis is structured with regard to the design and use of artificial muscle in robotics. The thesis starts with a theoretical section where different types of artificial muscles are described with their advantages and disadvantages. After considering all the types of described muscles, one species was selected for further processing. Vacuum-controlled origami muscles were chosen for use in a small manipulation device. After the design of the whole machine, the risk analysis and the economic evaluation of the whole design were carried out.

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Konez, Eroglu Aylin. "Development And Analysis Of Grasshopper-like Jumping Mechanism In Biomimetic Approach." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608733/index.pdf.

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Highly effective and power efficient biological mechanisms are common in nature. The use of biological design principles in engineering domain requires adequate training in both engineering and biological domains. This requires cooperation between biologists and engineers that leads to a new discipline of biomimetic science and engineering. Biomimetic is the abstraction of good design from nature. Because of the fact that biomimetic design has an important place in mechatronic applications, this study is directed towards biomimetic design of grasshopper-like jumping mechanism. A biomimetic design procedure is developed and steps of the procedure have followed through all the study. A literature survey on jumping mechanisms of grasshoppers and jumping robots and bio-robots are done and specifically apteral types of grasshoppers are observed. After the inspections, 2D and 3D mathematical models are developed representing the kinematics and dynamics of the hind leg movements. Body-femur, femur-tibia and tibia-ground angles until take-off are obtained from the mathematical leg models. The force analysis of the leg models with artificial muscles and biological muscles are derived from the torque analysis. A simulation program is used with a simple model for verification. The horizontal displacement of jumping is compared with the data obtained from the simulation program and equation of motion solutions with and without air resistance. Actuators are the muscles of robots that lead robots to move and have an important place in robotics. In this scope, artificial muscles are studied as a fourth step of biomimetic design. A few ready-made artificial muscles were selected as an actuator of the grasshopper-like jumping mechanism at the beginning of the study. Because of their disadvantages, a new artificial muscle is designed and manufactured for mini bio-robot applications. An artificial muscle is designed to be driven by an explosion obtained due to the voltage applied in a piston and cylinder system filled with dielectric fluid. A 3.78-mm diameter Teflon piston is fitted with a clearance into a Teflon cylinder filled with a 25.7- mm fluid height and maximum 225 V is applied to the electrodes by using an electrical discharge machine (EDM) circuit. The force on the piston is measured by using a set-up of Kistler piezoelectric low level force sensor. The data obtained from the sensor is captured by using an oscilloscope, a charge meter, and a GPIB connecting card with software, Agilent. From the experiments, the new artificial muscle force is about 300 mN giving a 38:1 force to weight ratio and percentage elongation is expected to be higher than that of the natural muscles and the other artificial muscles. From the force analysis of the leg model, it is shown that the measured force is not enough alone for jumping of an about 500 mgr body. An additional artificial muscle or a single muscle designed with the same operating principle giving higher force to weight ratio is recommended as a future study.

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Bassil, Maria. "Muscles artificiels à base d’hydrogel électroactif." Thesis, Lyon 1, 2009. http://www.theses.fr/2009LYO10127/document.

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Les hydrogels de Polyacrylamide (PAAM) hydrolysés sont des matériaux électroactifs biocompatibles non biodégradables. Ils possèdent des propriétés très proches de celles du muscle naturel et leur mode opérationnel basé sur la diffusion d’ions est similaire à celui existant dans les tissus musculaires naturels. Compte tenu de ces caractéristiques, ces hydrogels sont de bons candidats pour la conception de nouveaux muscles artificiels. Le problème qui limite leur utilisation réside dans leur temps de réponse qui reste encore inférieur à celui du système de fibres musculaires naturelles. Leur fonction actuatrice est limitée par le phénomène de diffusion en raison de leur structure massique qui est à l’origine de cycles de fonctionnement relativement lents. Dans le but de développer un nouveau système artificiel mimant le comportement du muscle squelettique naturel cette étude se divise en deux grandes étapes. La première étape vise le développement d’une étude de la synthèse de l’hydrogel de PAAM et de son mode de fonctionnement. Dans cette étude les effets des paramètres gouvernant la polymérisation sur les propriétés des hydrogels sont évalués. Les propriétés électrochimiques et le mécanisme d’activation des actuateurs soumis à une excitation électrique sont étudiés et le mode de fonctionnement des actuateurs est caractérisé et expliqué. La seconde étape est la proposition et le développement d’une nouvelle architecture de muscle artificiel à base de PAAM. Cette architecture consiste en une structure fibreuse du gel encapsulée par une couche en gel conducteur jouant le rôle d’électrodes. La structure fibreuse permet au système d’exhiber une réponse rapide et la couche en gel améliore ses propriétés mécaniques. Comme un premier pas dans la réalisation du modèle nous avons mis en place un nouveau procédé basé sur la technique d’électrofilage qui permet la génération de fibres linéairement disposées. En utilisant ce processus nous avons réussi à fabriquer des microfibres de PAAM réticulées, électroactives montrant des réponses rapides
Hydrolyzed Polyacrylamide (PAAM) hydrogels are electroactive, biocompatible and non-biodegradable materials. Their main attractive characteristic is their operative similarity with biological muscles and particularly their life-like movement. They suit better the artificial muscle fabrication despite their response time which stays low compared to natural human muscle due to their bulky structure and due to the kinetics of the size dependence of their volume change. In order to copy the natural skeletal muscle design into a new artificial muscle system this study is divided into two steps. The first step is the development of a comprehensive study of the hydrogel itself in order to obtain the elementary background needed for the design of actuating devices based on this material. The effect of polymerization parameter on the hydrogel properties is investigated. The electrochemical properties and actuation mechanisms of the hydrogel is studied, the bending of PAAM actuators induced by electric field is discussed and a mechanism for the bending phenomenon is proposed. The second step is the proposition of a new artificial muscle architecture based on PAAM hydrogel. The model consists on a fiber like elements of hydrolyzed PAAM, working in parallel, embedded in a thin conducting gel layer which plays the role of electrodes. The fiber-like elements enable the system to exhibit relatively rapid response and the gel layers enhance their mechanical properties. Aiming to realize the model we have put in place a new electrospinning setup which is a modified process for the production of micro to nanofibers via electrostatic fiber spinning of polymer solutions. The main advantage of this technology is to produce aligned electrospun fibers over large areas by simple and a low cost process making it possible to produce fiberbased devices efficiently and economically. Using this setup, we succeeded in the fabrication of electroactive crosslinked hydrogel microfibers that can achieve fast electroactive response

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32

Diaz, Zagal Sergio. "Conception et développement d’un mini-actionneur à muscle artificiel : application à la robotique médicale." Toulouse, INSA, 2007. http://eprint.insa-toulouse.fr/archive/00000205/.

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L’expérience du laboratoire en matière de muscles artificiels pneumatiques pour la robotique est appliquée au développement de mini-actionneurs à muscles artificiels destinés à des systèmes robotiques miniatures. Le domaine de la robotique médicale est tout particulièrement visé. Le but de ce travail est de mettre au point et développer des actionneurs dont les caractéristiques et les performances correspondent à ceux présentés par les muscles naturels. Ces actionneurs seront utilisés dans le domaine de la robotique et dans le domaine médical. Ainsi, dans un premier temps on s’est intéressé au développement et à l’étude du muscle artificiel pneumatique de McKibben. Il s’agit d’un type d’actionneur très performant, présentant des propriétés satisfaisantes, se rapprochant énormément de celles des muscles naturels. De ce fait, leur utilisation dans le domaine de la robotique est très avantageuse. Cependant, la source énergétique qu’ils utilisent - l’air comprimé – présente un sérieux frein vis-à-vis d’une utilisation flexible ou médicale. De ce fait, dans un deuxième temps, on a adapté ces muscles de McKibben au domaine biomédical en remplaçant l’air comprimé par des résines échangeuses d’ions ou des hydrogels. On a ainsi développé et étudié des muscles mécanochimiques basés sur des muscles de McKibben
The experience of the laboratory in the matter of pneumatic artificial muscle for the robotics is applied to the development of mini-actuators with artificial muscles intended for miniature robot-like systems. The field of medical robotics is particularly aimed. The goal of this work is to develop actuators whose characteristics and performances correspond to those presented by the natural muscles. These actuators will be used in the field of robotics and the medical field. Thus, initially we were interested in the development and the study of the pneumatic artificial muscle of McKibben. It is a type of very powerful actuator, presenting satisfactory properties, approaching those of the natural muscles enormously. So their use in the field of robotics is very advantageous. However, the energy source that they use - compressed air - presents a serious restraint with respect to a flexible or medical use. So in the second time, we adapted these muscles of McKibben to the biomedical field by replacing the compressed air by exchanging resins of ions or hydrogels. We thus developed and studied muscles mecanochimic based on McKibben’s muscles

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33

Petsch, Sebastian [Verfasser], and Hans [Akademischer Betreuer] Zappe. "Artificial muscle micro-optics." Freiburg : Universität, 2016. http://d-nb.info/1122831811/34.

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34

Nemer, Sérgio Nogueira. "Avaliação da força muscular inspiratória (Pi Max), da atividade do centro respiratório (P 0.1) e da relação da atividade do centro respiratório/força muscular inspiratória (P 0.1 / Pi Max) sobre o desmame da ventilação mecânica." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/5/5150/tde-02082007-104326/.

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Introdução: a hipótese deste estudo é de que a Pressão inspiratória máxima, Pressão de oclusão traqueal e sua razão podem predizer a evolução do desmame da ventilação mecânica em uma população mista de Terapia Intensiva. Métodos: A Pi Max , P 0.1 e a razão P 0.1 / Pi Max foram mensuradas em setenta pacientes consecutivos , intubados ou traqueostomizados, e ventilados mecanicamente, que preencheram os critérios para desmame da ventilação mecânica. Após a mensuração da Pi Max, P 0.1 e ainda da freqüência respiratória e volume corrente em litros com o cálculo da relação FR/VC e do produto P 0.1 x FR/VC, os pacientes foram submetidos a um teste de respiração espontânea. Os pacientes que toleraram o teste de respiração espontânea e não precisaram retornar para a ventilação mecânica no período de 24 horas foram considerados desmamados. A sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo, diagnóstico de acurácia e a área sob a curva ROC (receiver operating characteristic curve) foram calculadas. Resultados: Os valores médios da P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC e P 0.1 x FR /VC foram de 2,49±1,2, -34,6±13, 0,07±0,01, 75,4±33 e 184,6±123 respectivamente para os pacientes desmamados e 4,36± 2,0, -32,1±11,0 , 0,15± 0,09, 148,4± 42 e 652,9± 358 para os não desmamados da ventilação mecânica. Todos os índices distinguiram entre os pacientes desmamados e não desmamados, à exceção da Pi Max. A sensibilidade para a P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC e P 0.1 x FR /VC foi de 78,85, 65,38, 80,77, 82,69, 88,46 respectivamente. A especificidade para a P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC e P 0.1 x FR /VC foi de 72,2, 38,8, 72,2, 83,3, 72,2 respectivamente. Os valores preditivos positivos para a P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC e P 0.1 x FR /VC foram respectivamente 89,1, 75,5, 89,3, 93,4 e 90,2. Os valores preditivos negativos para a P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC e P 0.1 x FR /VC foram respectivamente de 54,1, 28,0, 56,5, 62,5 e 68,4. O diagnóstico de acurácia para a P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC e P 0.1 x FR /VC foi respectivamente de 77,1, 58,5, 78,5, 82,8 e 84,2. As áreas abaixo da curva ROC para a P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC e P 0.1 x FR /VC foram respectivamente 0,76± 0,06, 0,52±0,08 , 0,78±0,06, 0,90±0,04 e 0,84±0,05. A comparação da áreas abaixo da curva ROC mostrou que os melhores índices foram a relação FR/VC, o produto P 0.1 x FR/VC e a relação P 0.1 / Pi Max não havendo diferença estatística entre eles. A pior área abaixo da curva ROC foi do índice Pi Max. Os índices de desmame da ventilação mecânica P 0.1, Pi Max e P 0.1/ Pi Max não foram diferentes estatisticamente entre os pacientes intubados e traqueostomizados. Conclusão: os melhores índices foram a relação FR/VC, o produto P 0.1 x FR/VC e a relação P 0.1 / Pi Max não havendo diferença estatística entre eles.
Introduction: We hypothesized that maximal inspiratory pressure (Pi Max), airway tracheal occlusion pressure (P 0.1) and its ratio (P 0.1/Pi Max) can be used to predict weaning outcome in a mixed ICU mechanically ventilated patients. Methods: Pi Max, P 0.1 and P 0.1 / Pi Max ratio were measured in seventy consecutive intubated or tracheostomized, mechanically ventilated patients, who fulfilled weaning criteria. After these measurements of Pi Max, P0.1, respiratory rate and expiratory tidal volume (L) with the calculation of f / Vt ratio and the product P0.1x f / Vt , the patients were submitted to a spontaneous breathing trial (SBT) . Those who were able to sustain the SBT and had no need to return to mechanical ventilation in the following 24 hours were considered weaned. The sensitivity, specificity, positive predictive value, negative predictive value, diagnostic accuracy and Receiver- operating-characteristics (ROC) curves for this population were calculated. Results: The mean value of P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC e P 0.1 x FR /VC were 2,49 ±1,2, -34,6± 13, 0,07± 0,01, 75,4±33 and 184,6±123 respectively for the weaned patients and 4,36± 2,0, -32,1±11,0 , 0,15± 0,09, 148,4± 42 e 652,9± 358 for the not weaned patients. All the indexes distinguished between the weaned and not weaned patient, except for the Pi Max. The sensitivity for the P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC and P 0.1 x FR /VC were respectively 78,85, 65,38, 80,77, 82,69, 88,46. The specificity for P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC and P 0.1 x FR /VC were 72,2, 38,8, 72,2, 83,3, 72,2 respectively. The positive predictive value for P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC and P 0.1 x FR /VC were respectively 89,1, 75,5, 89,3, 93,4 e 90,2. The negative predictive value for P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC and P 0.1 x FR /VC were respectively 54,1, 28,0, 56,5, 62,5 e 68,4. The diagnostic accuracy for P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC and P 0.1 x FR /VC were respectively 77,1, 58,5, 78,5, 82,8 e 84,2. The area under the ROC curves for P 0.1 , Pi Max, P 0.1 / Pi Max, FR / VC and P 0.1 x FR /VC were respectively 0,76± 0,06, 0,52±0,08 , 0,78±0,06, 0,90±0,04 e 0,84±0,05. The comparison among the areas under the ROC curves showed that the best weaning indexes were f / Vt ratio, the product P 0.1 x f / Vt and the P0.1/ Pi Max ratio with no statistic differences among them. The Pi Max presented the smaller area under the ROC curve. The weaning indexes P 0.1, Pi Max e P 0.1/ Pi Max were not statistically different between intubated or tracheostomized patients. Conclusion: The best weaning indexes were f/Vt ratio , the product P 0.1 x f/Vt and the P 0.1 / Pi Max ratio with no statistically difference among them.

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Amaral, Ian P. G. "Transcriptional regulation in skeletal muscle of zebrafish in response to nutritional status, photoperiod and experimental selection for body size." Thesis, University of St Andrews, 2012. http://hdl.handle.net/10023/2616.

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In the present study, the ease of rearing, short generation time and molecular research tools available for the zebrafish model (Danio rerio, Hamilton) were exploited to investigate transcriptional regulation in relation to feeding, photoperiod and experimental selection. Chapter 2 describes transcriptional regulation in fast skeletal muscle following fasting and a single satiating meal of bloodworms. Changes in transcript abundance were investigated in relation to the food content in the gut. Using qPCR, the transcription patterns of 16 genes comprising the insulin-like growth factor (IGF) system were characterized, and differential regulation between some of the paralogues was recorded. For example, feeding was associated with upregulation of igf1a and igf2b at 3 and 6h after the single-meal was offered, respectively, whereas igf1b was not detected in skeletal muscle. On the other hand, fasting triggered the upregulation of the igf1 receptors and igfbp1a/b, the only binding proteins whose transcription was responsive to a single-satiating meal. In addition to the investigation of the IGF-axis, an agnostic approach was used to discover other genes involved in transcriptional response to nutritional status, by employing a whole-genome microarray containing 44K probes. This resulted in the discovery of 147 genes in skeletal muscle that were differentially expressed between fasting and satiation. Ubiquitin-ligases involved in proteasome-mediated protein degradation, and antiproliferative and pro-apoptotic genes were among the genes upregulated during fasting, whereas satiation resulted in an upregulation of genes involved in protein synthesis and folding, and a gene highly correlated with growth in mice and fish, the enzyme ornithine decarboxylase 1. Zebrafish exhibit circadian rhythms of breeding, locomotor activity and feeding that are controlled by molecular clock mechanisms in central and peripheral organs. In chapter 3 the transcription of 17 known clock genes was investigated in skeletal muscle in relation to the photoperiod and food content in the gut. The hypothesis that myogenic regulatory factors and components of the IGF-pathway were clock-controlled was also tested. Positive (clock1 and bmal1 paralogues) and negative oscillators (cry1a and per genes) showed a strong circadian pattern in skeletal muscle in anti-phase with each other. MyoD was not clock-controlled in zebrafish in contrast to findings in mice, whereas myf6 showed a circadian pattern of expression in phase with clock and bmal. Similarly, the expression of two IGF binding proteins (igfbp3 and 5b) was circadian and in phase with the positive oscillators clock and bmal. It was also found that some paralogues responded differently to photoperiod. For example, clock1a was 3-fold more responsive than clock1b. Cry1b did not show a circadian pattern of expression. These patterns of expression provide evidence that the molecular clock mechanisms in skeletal muscle are synchronized with the molecular clock in central pacemaker organs such as eyes and the pineal gland. Using the short generation time of zebrafish the effects of selective breeding for body size at age were investigated and are described in chapter 4. Three rounds of artificial selection for small (S-lineage) and large body size (L-lineage) resulted in zebrafish populations whose average standard length were, respectively, 2% lower and 10% higher than an unselected control lineage (U-lineage). Fish from the L-lineage showed an increased egg production and bigger egg size with more yolk, possibly contributing to the larger body size observed in the early larval stage (6dpf) of fish from this lineage. Fish from S- and L-lineage exposed to fasting and refeeding showed very similar feed intake, providing evidence that experimental selection did not cause significant changes in appetite control. Investigation of the expression of the IGF-axis and nutritionally-response in skeletal muscle after fasting and refeeding revealed that the pattern of expression was not different between the selected lineages, but that a differential responsiveness was observed in a limited number of genes, providing evidence that experimental selection might have changed the way fish allocate the energy acquired through feeding. For example, a constitutive higher expression of igf1a was recorded in skeletal muscle of fish from the L-lineage whereas igfbp1a/b transcripts were higher in muscle of fish from the S-lineage. These findings demonstrate the rapid changes in growth and transcriptional response in skeletal muscle of zebrafish after only three rounds of selection. Furthermore, it provides evidences that differences in growth during embryonic and larval stages might be related to higher levels of energy deposited during oogenesis, whereas differences in adult fish were better explained by changes in energy allocation instead of energy acquisition. In chapter 5 the main findings made during this study and their impact on the literature are discussed.

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36

Creemers, Warren. "On the Recognition of Emotion from Physiological Data." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2013. https://ro.ecu.edu.au/theses/680.

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This work encompasses several objectives, but is primarily concerned with an experiment where 33 participants were shown 32 slides in order to create ‗weakly induced emotions‘. Recordings of the participants‘ physiological state were taken as well as a self report of their emotional state. We then used an assortment of classifiers to predict emotional state from the recorded physiological signals, a process known as Physiological Pattern Recognition (PPR). We investigated techniques for recording, processing and extracting features from six different physiological signals: Electrocardiogram (ECG), Blood Volume Pulse (BVP), Galvanic Skin Response (GSR), Electromyography (EMG), for the corrugator muscle, skin temperature for the finger and respiratory rate. Improvements to the state of PPR emotion detection were made by allowing for 9 different weakly induced emotional states to be detected at nearly 65% accuracy. This is an improvement in the number of states readily detectable. The work presents many investigations into numerical feature extraction from physiological signals and has a chapter dedicated to collating and trialing facial electromyography techniques. There is also a hardware device we created to collect participant self reported emotional states which showed several improvements to experimental procedure.

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37

Rudder, Benjamin A. "Motor protein inspired "artificial muscle" actuator." Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/105648/1/Benjamin_Rudder_Thesis.pdf.

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In this thesis, the foundation is laid for a new form of artificial muscle, which more closely mimics the structure of skeletal muscle down to its most basic units; motor proteins. An electro-mechanical drive method together with the geometrical properties of the sarcomere, aim to create an efficient, safe, and low temperature device which can be implanted or be in contact with skin. The feasibility of the principle is investigated, physical size limitations of each working element ascertained, and two (larger scale) prototypes produced. A numerical simulation is developed to enable optimization through refining the design with further conditions.

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38

Bassil, Maria. "Muscles artificiels à base d'hydrogel électroactif." Phd thesis, Université Claude Bernard - Lyon I, 2009. http://tel.archives-ouvertes.fr/tel-00688340.

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Les hydrogels de Polyacrylamide (PAAM) hydrolysés sont des matériaux électroactifs biocompatibles non biodégradables. Ils possèdent des propriétés très proches de celles du muscle naturel et leur mode opérationnel basé sur la diffusion d'ions est similaire à celui existant dans les tissus musculaires naturels. Compte tenu de ces caractéristiques, ces hydrogels sont de bons candidats pour la conception de nouveaux muscles artificiels. Le problème qui limite leur utilisation réside dans leur temps de réponse qui reste encore inférieur à celui du système de fibres musculaires naturelles. Leur fonction actuatrice est limitée par le phénomène de diffusion en raison de leur structure massique qui est à l'origine de cycles de fonctionnement relativement lents. Dans le but de développer un nouveau système artificiel mimant le comportement du muscle squelettique naturel cette étude se divise en deux grandes étapes. La première étape vise le développement d'une étude de la synthèse de l'hydrogel de PAAM et de son mode de fonctionnement. Dans cette étude les effets des paramètres gouvernant la polymérisation sur les propriétés des hydrogels sont évalués. Les propriétés électrochimiques et le mécanisme d'activation des actuateurs soumis à une excitation électrique sont étudiés et le mode de fonctionnement des actuateurs est caractérisé et expliqué. La seconde étape est la proposition et le développement d'une nouvelle architecture de muscle artificiel à base de PAAM. Cette architecture consiste en une structure fibreuse du gel encapsulée par une couche en gel conducteur jouant le rôle d'électrodes. La structure fibreuse permet au système d'exhiber une réponse rapide et la couche en gel améliore ses propriétés mécaniques. Comme un premier pas dans la réalisation du modèle nous avons mis en place un nouveau procédé basé sur la technique d'électrofilage qui permet la génération de fibres linéairement disposées. En utilisant ce processus nous avons réussi à fabriquer des microfibres de PAAM réticulées, électroactives montrant des réponses rapides.

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39

Henke, E. F. Markus, Samuel Schlatter, and Iain A. Anderson. "Soft dielectric elastomer oscillators driving bioinspired robots." Mary Ann Liebert, 2017. https://tud.qucosa.de/id/qucosa%3A32850.

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Entirely soft robots with animal-like behavior and integrated artificial nervous systems will open up totally new perspectives and applications. To produce them we must integrate control and actuation in the same soft structure. Soft actuators (e.g. pneumatic, and hydraulic) exist but electronics are hard and stiff and remotely located. We present novel soft, electronicsfree dielectric elastomer oscillators, able to drive bioinspired robots. As a demonstrator we present a robot that mimics the crawling motion of the caterpillar, with integrated artificial nervous system, soft actuators and without any conventional stiff electronic parts. Supplied with an external DC voltage, the robot autonomously generates all signals necessary to drive its dielectric elastomer actuators, and translates an in-plane electromechanical oscillation into a crawling locomotion movement. Thereby, all functional and supporting parts are made of polymer materials and carbon. Besides the basic design of this first electronic-free, biomimetic robot we present prospects to control the general behavior of such robots. The absence of conventional stiff electronics and the exclusive use of polymeric materials will provide a large step towards real animal-like robots, compliant human machine interfaces and a new class of distributed, neuron-like internal control for robotic systems.

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40

Vanderhoff, Alexandra. "Metal hydride fluidic artificial muscle actuation system." abstract and full text PDF (free order & download UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1460785.

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41

Gotti, Carlo <1988&gt. "Electrospun hierarchical artificial muscle for soft robotics applications." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10412/1/gotti_carlo_tesi.pdf.

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Nowadays, one of the most ambitious challenges in soft robotics is the development of actuators capable to achieve performance comparable to skeletal muscles. Scientists have been working for decades, inspired by Nature, to mimic both their complex structure and their perfectly balanced features in terms of linear contraction, force-to-weight ratio, scalability and flexibility. The present Thesis, contextualized within the FET open Horizon 2020 project MAGNIFY, aims to develop a new family of innovative flexible actuators in the field of soft-robotics. For the realization of this actuator, a biomimetic approach has been chosen, drawing inspiration from skeletal muscle. Their hierarchical fibrous structure was mimicked employing the electrospinning technique, while the contraction of sarcomeres was designed employing chains of molecular machines, supramolecular systems capable of performing movements useful to execute specific tasks. The first part deals with the design and production of the basic unit of the artificial muscle, the artificial myofibril, consisting in a novel electrospun core-shell nanofiber, with elastomeric shell and electrically conductive core, coupled with a conductive coating, for the realization of which numerous strategies have been investigated. The second part deals instead with the integration of molecular machines (provided by the project partners) inside these artificial myofibrils, preceded by the study of several model molecules, aimed at simulating the presence of these molecular machines during the initial phases of the project. The last part concerns the realization of an electrospun multiscale hierarchical structure, aimed at reproducing the entire muscle morphology and fibrous organization. These research will be joined together in the near future like the pieces of a puzzle, recreating the artificial actuator most similar to biological muscle ever made, composed of millions of artificial myofibrils, electrically activated in which the nano-scale movement of molecular machines will be incrementally amplified to the macro-scale contraction of the artificial muscle.

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42

Mablouké, Cécile. "Étude des ratios isotopiques du carbone et de l'azote de la matière organique particulaire et des muscles de poissons d'intérêt commercial d'écosystèmes côtiers tropicaux du sud-ouest de l'océan Indien : contribution à l'étude de leur fonctionnement." Thesis, La Réunion, 2013. http://www.theses.fr/2013LARE0017/document.

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L'objectif de cette thèse est l'étude du régime alimentaire de poissons côtiers commerciaux et la compréhension de l'utilité des isotopes stables du carbone (δ13C) et de l'azote (δ15N) dans l'étude des niches trophiques et de l'occupation des habitats côtiers par les poissons dans le sud-ouest de l'océan Indien. Dans la Baie de La Possession, les espèces représentatives des récifs artificiels immergés en 2003 (Luljanus kasmira, Priacanthus hamrur et Selar crumenophthalmus) ingèrent surtout des proies pélagiques et partitionnent leurs niches trophiques afin de limiter la compétition. Les valeurs de δ15N sont positivement corrélées avec la taille des poissons, traduisant une contribution croissante des larves de poissons au régime alimentaire. Les isotopes stables de la matière organique particulaire (MOP) ont été analysés à microéchelle (< 10 km) dans la Baie de La Possession, à mésoéchelle (10aines de km) autour de La Réunion et, pour les muscles de poissons à macroéchelle (l00aines de km) le long,du plateau .des Mascareignes.et du cana1 du Mozambique. À microéchelle, le δ15N de la MOP ne varie pas; à mésoechelle, Il existe un enrichissement significatif en 15N dans le sud-ouest de l'île; à macroéchelle, les muscles des poissons s'enrichissent progressivement en 15N vers le nord. À microéchelle, la MOP est enrichie en 13C à faible profondeur; à mésoéchelle, les stations de l'est sont enrichies en 13C ; à macroéchelle, aucune tendance n'est observée. Ainsi, l'utilité des isotopes stables du carbone pour l'étude de l'utilisation des habitats côtiers est limitée à méso- et macroéchelle et les isotopes stables de l'azote constituent un outil plus pertinent à macroéchelle
The aim of this thesis was to study the feeding habits of coastal fish species of commercial interest andto use stable isotopes of carbon (δ13C) and nitrogen (δ15N) to investigate the trophic niches of fish and their use of coastal habitats in the south-west Indian Ocean. In the Bay of La Possession, the species among the most abundant around the artificial reefs immersed in 2003 (Luljanus kasmira, Priacanthus hamrur and Selar crumenophthalmus) feed essentially on pelagic prey and partition their trophic niche to limit interspecific competition. There was also a positive correlation between fish size and muscle δ15N values due to fish larvae contributing more to the diet of fish with age. The stable isotopie composition of the particulate organic matter (POM) was measured at the microscale (< 10 km) in the Bay of La Possession, the mesoscale (10's of km) around Reunion Island and, for the fish muscles, at the macroscale 100’s of km) along the Mascarene plateau and the Mozambique channel. At microscale, POM δ15N values do not show any spatial variability; at mesoscale, POM is 15N-enriched in the south-west of Reunion Island; at macroscale, fish muscles are gradually 15N-enriched towards the north. At microscale, POM shows a 13C-enrichment on the shallowest station; at mesoscale, stations on the east coast of the island are 13C-enriched compared to the west; at macroscale, POMδ13C values are not significantly correlated with latitude. Thus, the stable isotopes of carbon do not seem to be appropriate for the study of fish coastal habitat use at the meso- and macroscale, and the stable isotopes of nitrogen represent a better indicator of fish habitat use at the macroscale

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Mirvakili, Seyed Mohammad. "Niobium nanowire yarns and their application as artificial muscle." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44257.

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Since the discovery of carbon nanotubes, various devices have been made in different fields of science and engineering. The mechanical and electrical properties that carbon nanotubes offer make them a great candidate for use in the structure of artificial muscles. In this thesis, for the first time, we have demonstrated that metallic nanowires can be engineered to become strong and comparable to the CNT yarns in mechanical and electrical properties. The niobium yarns offer conductivity of up to 3×10⁶ S m-¹, tensile strength of up to 1.1 GPa and Young’s modulus of 19 GPa. The niobium nanowire fibres are fabricated by extracting the niobium nanowires from copper-niobium nano-composite matrix, which was made by using a severe plastic deformation process. As a practical application, torsional artificial muscles were made out of the niobium yarns by twisting and impregnating them with paraffin wax. Upon applying voltage to the twisted yarn the wax melts and expands due to the heat generated by the current. Thermal expansion of wax untwists the yarn, which translated to torsional actuation. Torsional speeds of 7,200 RPM (in a destructive test) and 1,800 RPM (continuous) were achieved. In addition to torsional actuation, niobium yarns also can provide up to 0.24% of isobaric tensile actuation along the yarn’s axis at 20 MPa load. Due to the high conductivity of the niobium yarns, the actuator can be made to actuate by even one single 1.5 V battery (for a 1 cm of niobium yarn). The electrochemical capacitance of niobium yarns was measured to be 1.3×10⁷ F m-³ at a scan rate of 25 mV s-¹ in 0.2 M TBAPF₆ salt dissolved in acetonitrile. This value is comparable to the electrochemical capacitance of the carbon multi-walled nanotube yarns.

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Pytel, Rachel Zimet. "Artificial muscle morphology : structure/property relationships in polypyrrole actuators." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/39537.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2007.
Includes bibliographical references (leaves 183-204).
We seek to improve polypyrrole and other conducting polymer actuators by discovering and exploiting the connection between nanoscale transport events and macroscale active strain. To this end we have used diffraction and electron microscopy to investigate the microstructure of polypyrrole. and propose a new description consisting of disordered polypyrrole chains held together by small crystalline bundles, around which solvent and counterions are randomly distributed. We utilize different modes of deformation to impart orientational texture to polypyrrole films, and show that by controlling polymer chain conformation and packing at a sub-micron level a conducting polymer actuator can be engineered that shows a significantly larger macroscopic electroactive response. We also alter the synthesis and doping conditions to produce films with widely varying surface morphologies, allowing us to control the rate of electroactive response. Our detailed understanding of polypyrrole morphology at different lengthscales provides valuable insight to the mechanisms of polypyrrole actuation, and has helped us process polypyrrole more intelligently for improved electroactive devices.
by Rachel Zimet Pytel.
Ph.D.

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Liu, Ming Ming. "Dynamic muscle force prediction from EMG signals using artificial neural networks." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq20875.pdf.

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46

Murillo, Jaime. "Design of a Pneumatic Artificial Muscle for Powered Lower Limb Prostheses." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/24104.

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Ideal prostheses are defined as artificial limbs that would permit physically impaired individuals freedom of movement and independence rather than a life of disability and dependence. Current lower limb prostheses range from a single mechanical revolute joint to advanced microprocessor controlled mechanisms. Despite the advancement in technology and medicine, current lower limb prostheses are still lacking an actuation element, which prohibits patients from regaining their original mobility and improving their quality of life. This thesis aims to design and test a Pneumatic Artificial Muscle that would actuate lower limb prostheses. This would offer patients the ability to ascend and descend stairs as well as standing up from a sitting position. A comprehensive study of knee biomechanics is first accomplished to characterize the actuation requirement, and subsequently a Pneumatic Artificial Muscle design is proposed. A novel design of muscle end fixtures is presented which would allow the muscle to operate at a gage pressure surpassing 2.76 MPa (i.e. 400 psi) and yield a muscle force that is at least 3 times greater than that produced by any existing equivalent Pneumatic Artificial Muscle. Finally, the proposed Pneumatic Artificial Muscle is tested and validated to verify that it meets the size, weight, kinetic and kinematic requirements of human knee articulation.

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Moore, Wayne Allen Jr. "Acute and Chronic Effects of Artificial Rearing on Rat Genioglossus Muscle." VCU Scholars Compass, 2005. http://scholarscompass.vcu.edu/etd/885.

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In most mammals, nutritive suckling is critical during the early neonatal period. The genioglossus (GG) muscle in rat plays an important role in protruding the tongue for efficient suckling. The purpose of this study was to examine the contractile properties and myosin heavy chain (MHC) phenotype of the GG following an early period of artificial rearing, which reduced nutritive suckling. Beginning at three days of age Sprague-Dawley rats were fed via implanted gastric cannula until postnatal day 14 (P14). At P14, artificially reared (AR) rat pups were either placed with a lactating dam until the end of the weaning period and allowed to mature until postnatal day 42 (P42), or anesthetized and prepared for physiological experimentation. GG contractile properties at P14 and P42 in AR and dam reared (DR) rats were obtained with a force transducer and digital recording system through stimulation of the medial branch of the hypoglossal nerve. Following physiological experimentation, muscle samples were removed and stored for MHC analysis. Comparisons were made between AR and DR groups at P14 and P42. At P14 maximum tetanic tension and fatigue index were lower in the AR group than the DR group and no differences were found in MHC distribution. By day 42, AR rats had a higher fatigue index that DR rats and DR rats had a higher percentage of MHCIIa than AR rats. The artificial rearing technique employed in this study was adequate to produce chronic changes in fatigue resistance and MHC distribution in GG muscle. GG muscle of premature human infants requiring early artificial feedings may develop similar changes in their contractile characteristics and MHC phenotype.

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Secord, Thomas W. (Thomas William). "Design and application of a cellular, piezoelectric, artificial muscle actuator for biorobotic systems." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/61612.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 219-227).
One of the foremost challenges in robotics is the development of muscle-like actuators that have the capability to reproduce the smooth motions observed in animals. Biological muscles have a unique cellular structure that departs from traditional electromechanical actuators in several ways. A muscle consists of a vast number of muscle fibers and, more fundamentally, sarcomeres that act as cellular units or building blocks. A muscle's output force and displacement are the aggregate effect of the individual building blocks. Thus, without using gearing or transmissions, muscles can be tailored to a range of loads, satisfying specific force and displacement requirements. These natural actuators are desirable for biorobotic applications, but many of their characteristics have been difficult to reproduce artificially. This thesis develops and applies a new artificial muscle actuator based on piezoelectric technology. The essential approach is to use a subdivided, cellular architecture inspired by natural muscle. The primary contributions of this work stem from three sequential aims. The first aim is to develop the operating principles and design of the actuator cellular units. The basic operating principle of the actuator involves nested flexural amplifiers applied to piezoelectric stacks thereby creating an output length strain commensurate with natural muscle. The second aim is to further improve performance of the actuator design by imparting tunable stiffness and resonance capabilities. This work demonstrates a previously unavailable level of tunability in both stiffness and resonance. The final aim is to showcase the capabilities of the actuator design by developing an underwater biorobotic fish system that utilizes the actuators for resonance-based locomotion. Each aspect of this thesis is supported by rigorous analysis and functional prototypes that augment broadly applicable design concepts.
by Thomas William Secord.
Ph.D.

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Sabourin, Nicaulas A. (Nicaulas Alexandre) 1978. "Artificial muscle technology applied towards treating ischemic mitral regurgitation caused by left ventricular remodeling." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/27117.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.
Includes bibliographical references (leaves 89-91).
Ischemic Mitral Regurgitation (MR) affects a large portion of patients suffering from ischemic heart disease. Significant MR develops in one quarter to one third of patients who suffer from ischemic heart disease and doubles their late mortality rate after a myocardial infarction or revascularization. MR is most often caused by the bulging, or remodeling, of the heart's left ventricle. This remodeling displaces the papillary muscles inside of the ventricle and tethers the mitral valve, preventing it from closing properly. Current treatments attempt to either repair or replace the valve. These treatments require the heart be stopped and the patient be placed on a cardiopulmonary bypass pump for many hours. Both treatment approaches have serious side-effects, including relapse of the MR as quickly as six months post-operatively. This thesis concerns the development of an active artificial muscle patch (AMP) for application to the exterior of the heart. The AMP constructively remodels the heart in order to alleviate MR. Two in-vivo experiments were conducted with a heart-gated fluid pumping apparatus connected to a balloon patch that successfully proofed the concept that an active patch can relieve MR. These experiments also established data on the mechanical requirements of such a patch. An in-vitro heart model was created to test iterations of AMP devices before undergoing further in-vivo studies. Development of an AMP using Nickel-Titanium shape memory alloy was begun and iterations of this device have had early success in in-vitro tests.
by Nicaulas A. Sabourin.
S.M.

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50

Bahrami, Sanaz. "Low-Profile Polymer Actuator Fabrication for Spastic Hand Exoskeletons." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/37953.

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Spasticity is a neurological impairment that presents itself in the form of a continuous muscle contraction, with the key motor deficit being impaired hand function. Hand exoskeleton technologies play a vital role in the therapeutic rehabilitation of this condition. The optimal design of these devices is currently a challenge due to the limited availability of actuation devices that are light weight, portable, and aesthetically pleasing. Natural muscles have many favourable characteristics, such as their high power-to-weight ratio, efficient energy conversion, and fast actuation times. Unfortunately, traditional systems such as pneumatics muscles and electromagnetic motors have yet to attain similar properties. These traditional actuators exhibit hysteretic performance, high manufacturing cost, low stroke, and limited cycle life. In recent years a new category of actuators has been developed from highly twisted and coiled low-cost nylon fibres such as fishing line and conductive sewing thread. These muscles produce a high specific work per cycle with a reversible contraction. This thesis develops and tests these twisted and coiled polymer (TCP) actuators using various nylon and polyethylene polymers in order to establish a foundation for their implementation as a novel actuation device in a spastic hand exoskeleton. An initial comprehensive experimental evaluation of several nylon fibres is completed by attempting to reproduce the work of previous researchers. Subsequently, the information obtained is taken and adapted to the development of UHMWPE TCPs and other types of nylon monofilament. This thesis characterizes the contractility and force output of these novel actuation devices.

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Dissertations / Theses on the topic 'Artificial muscles'

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