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1
Jernström, Agnes, e Martin Zakardissnehf. "Tracking Robot Using Ultrasonic Technology". Thesis, KTH, Maskinkonstruktion (Inst.), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-184494.
Testo completoAbstract (sommario):
This report describes the development of a robot that follows a transmitter within a chosen distance using ultrasonic technology. The purpose of the report is to investigate how the chosen distance affects the robots ability to react to changes in speed and direction. Two ultrasonic modules are placed on the robot and a third one is used as a transmitter. The transmitter sends out a burst of ultrasonic sound that the modules on the robot detect. Each of the two modules on the robot calculates the distance to the transmitter and this data is then used to determine the transmitter’s position. To allow a communication between the robot and the transmitter, they will be connected with a long wire. This is needed for the ultrasonic modules on the robot to start listening for a signal at the same time as the transmitter emits it. Two Arduino Unos are used to control the different components (one for the transmitter and one for the robot). This report describes the development process of the robot prototype and explains the theory behind the project. The results showed a relationship between the chosen distance and the robot's performance.Den här rapporten beskriver utvecklandet av en robot som följer en sändare inom ett givet avstånd. Syftet med rapporten är att undersöka hur det valda avståndet påverkar robotens förmåga att reagera på förändringar i hastighet och riktning. Två ultraljudsmoduler är placerade på roboten och en tredje används som sändare. Sändaren skickar ut en puls med ultraljud som sedan upptäcks av mottagarna på roboten. Båda modulerna på roboten räknar ut avståndet till sändaren och den informationen används sedan för att bestämma sändarens position. För att sändaren och roboten ska kunna kommunisera med varandra kopplas de ihop med en lång sladd. Detta behövs för att ultraljudsmodulerna på roboten ska börja lyssna efter en signal samtidigt som sändaren sänder ut den. Två Arduino Uno används för att styra de olika komponenterna, en för sändaren och en för roboten. Den här rapporten beskriver utvecklingsprocessen av prototyproboten och förklarar teorin bakom projektet. Resultatet visar att det finns ett samband mellan det valda avståndet och robotens prestanda.
2
Odell, Richard. "Tracking Robot : Distance keeping with ultrasonic transceivers". Thesis, KTH, Maskinkonstruktion (Inst.), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-184503.
Testo completoAbstract (sommario):
Fuel efficiency and safety in traffic is something that the vehicle industry prioritizes, although there is always room for improvements. This report presents how ultrasonic sensors could be used in road trains to keep distance between vehicles in order to reduce fuel consumption and increase safety. A small model in the size of a radio controlled car has been built to evaluate how this technology works in small scale. The results indicate that this can be done, and discuss the advantages and disadvantages with this technology in road trains.Bränsleförbrukning och säkerhet är två saker som prioriteras högt av fordonsindustrin, och det finns alltid plats för förbättringar. Denna rapport presenterar hur ultraljudssensorer kan användas för avståndshållning mellan fordon i vägtåg för att sänka bränsleförbrukningen och öka säkerheten. En liten modell i storleken av en radiostyrd bil har byggts för att undersöka hur denna teknologi fungerar i liten skala. Resultaten indikerar att denna teknik kan användas, och fördelar och nackdelar med metoden diskuteras.
3
Kuang, Wen-Tao. "Robot tracking with advanced ultrasonics". Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339960.
Testo completo
4
Kuang, Yang. "Resonance tracking and vibration stabilisation of ultrasonic surgical instruments". Thesis, University of Dundee, 2014. https://discovery.dundee.ac.uk/en/studentTheses/aa5a07a5-9a0e-45c4-9581-cf7dc8250c57.
Testo completoAbstract (sommario):
Ultrasonic surgical instruments actuated by piezoelectric transducers are usually driven at relatively high power levels to generate high vibration amplitude at the probe, which interact with biological tissues to achieve the desired effects. In operation, the high power level introduces nonlinearities into the behaviours of the piezoelectric transducer and the biological tissues place a load onto the transducer. Both the nonlinearities and the load result in variations in resonant frequency and electric impedance, which negatively affect the performance of the ultrasonic surgical instrument. The aim of this work was to develop an adaptive driving system to address the issue of the resonant frequency shift and impedance variation and to study its effectiveness in optimising the performance of ultrasonic surgical instruments. An ultrasonic planar tool based on piezocrystal PMN-PT was designed with various configurations as an alternative to the existing ultrasonic scalpels. To address the problem of resonant frequency shift and impedance variation observed on the planar tools in characterisation stage, an adaptive driving system was developed to track the resonant frequency and stabilise the vibration velocity. The system was carefully calibrated, and its effectiveness in optimising the performance of unloaded transducers in a broad frequency range was validated. The performance variation of the planar tool under the combined influence of high power level and external tissue loads was then investigated. The capacity of the adaptive driving system to optimise the performance of the planar tool under such conditions was then accessed by performing soft tissue penetrating test. Furthermore, a needle actuating device was designed to increase the visibility of medical needles in ultrasound guided percutaneous procedures. Its modal behaviour was studied in finite element analysis and verified by experimental characterisation. The ability of the adaptive driving system to improve the performance of the needle actuating device was accessed in pre-clinical trials. The results demonstrate that the adaptive driving system developed can track the resonant frequency and stabilise the vibration velocity of ultrasonic surgical instruments in frequency up to 5 MHz and power up to 300 W. By using the adaptive driving system, optimal performance of the planar tool and needle actuating device can be achieved in both unloaded and loaded conditions. The ultrasonic planar tool with PMN-PT is potentially useful in surgical operations. However, its performance is limited by the intensive heat generated in the joint area and the low Curie point of PMN-PT. The needle actuating device can increase the visibility of standard medical needles in colour Doppler imaging.
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Yang, Chuan-Hao. "A person-tracking mobile robot using an ultrasonic positioning system". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Dec%5FYang.pdf.
Testo completoAbstract (sommario):
Thesis (M.S. in Electrical and Computer Engineering)--Naval Postgraduate School, December 2005.Thesis Advisor(s): Xiaoping Yun. Includes bibliographical references (p.49-51). Also available online.
6
Egharevba, F. E. "Ultrasonic surface waves seam tracking and penetration control in thin materials". Thesis, Brunel University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234162.
Testo completo
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Jonsson, William. "Navigating Robot : Indoor Navigation Using Color Tracking and Ultrasonic Range Finders". Thesis, KTH, Maskinkonstruktion (Inst.), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-184496.
Testo completoAbstract (sommario):
Indoor navigation for autonomous vehicles and robots is an area of research and development with great promises for both current and future applications. Examples include robots assisting humans in indoor tasks, and industrial applications such as warehouse management using autonomous robots [Jensen, 2001]. This project examines the possibilities and limitations of navigating an autonomous vehicle in an enclosed area with the aid of visual recognition software and distancing sensors. The navigation works by using two sets of references: the distance and the relative angle to a point of origin that in this project is a visual reference attached to a flat and visually clean background. The autonomous vehicle is constructed with open source hardware and utilizes already available visual recognition software and all control software is written in Python 2.7. The scope of the project limits the navigation of the robot on a flat surface with no obstacles and with access to a nearby flat wall with a visual reference. A demonstrator was built and empirically tested for its navigational accuracy. The positional accuracy was found to have a mean deviation of ± 1 and ± 4.5 centimeters for the x and y-axis respectively.Navigering och lokalisering inomhus är ett hett forskningsområde både inom vetenskapen och ingenjörstillämpningar. Exempel på system som kan förbättras med sådan teknik är robotar som assisterar människor i hemmet samt automatisering av industrirobotar som är fria att röra sig över golvytor [Jensen, 2001]. Detta kandidatexamensprojekt undersöker möjligheterna och begränsningarna av navigering inomhus för en autonom robot med hjälp av färg-igenkännande bildbehandling och avståndssensorer. Navigeringen sker med hjälp av två riktmärken: en visuell referens monterad på en plan vägg och avståndet mellan robot och vägg. Robotens interna styrelektronik, sensorer samt mjukvara är alla open source. Bredden av projektet begränsas av villkoren att navigationen sker på en plan yta utan hinder samt tillgång till en plan vägg med en visuell referens. Slutgiltiga systemets navigationssäkerhet kontrollerades och mättes empiriskt och uppskattades till att ha en medelavvikelse på ± 1 cm och ± 4.6 cm för x respektive y-axeln.
8
Hoelscher, Joshua David. "Development of a Robust, Accurate Ultrasonic Tracking System for Image Guided Surgery". Available to subscribers only, 2008. http://proquest.umi.com/pqdweb?did=1674101291&sid=2&Fmt=2&clientId=1509&RQT=309&VName=PQD.
Testo completo
9
Goldsmith, Abraham Myron. "An inertial-optical tracking system for quantitative, freehand, 3D ultrasound". Worcester, Mass. Worcester Polytechnic Institute, 2008. http://www.wpi.edu/Pubs/ETD/Available/etd-011609-133509/.
Testo completo
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Dasari, Ganeshram. "Development of a robust 3-D ultrasonic tracking system for motion capture studies /". Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1796330211&sid=15&Fmt=2&clientId=1509&RQT=309&VName=PQD.
Testo completo
11
Dasari, Ganeshram. "DEVELOPMENT OF A ROBUST 3-D ULTRASONIC TRACKING SYSTEM FOR MOTION CAPTURE STUDIES". OpenSIUC, 2008. https://opensiuc.lib.siu.edu/theses/448.
Testo completoAbstract (sommario):
This work addresses the various stages involved in the development of a 3 dimensional tracking system based on ultrasonic transmitters and receivers. The hardware developed for this project can drive up to 24 ultrasonic transmitters and the receiver circuitry can detect signals from 8 receivers with high accuracy even in a noisy environment. Extensive experimentation has been done on the 1-D system and an accuracy of less than 1 mm was recorded except for certain points where the error is around 4.5 mm. This was due to one wavelength error in the time delay. A comprehensive calibration routine has also been developed for the system for easy and quick estimation of the receiver locations. The 3-D system was also tested and errors of up to 2.5cm were obtained.
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Lindberg, Frida. "Ultrasonic Quantification of Skeletal Muscle Dynamics : Feasibility and Limitations". Doctoral thesis, KTH, Medicinsk teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-122233.
Testo completoAbstract (sommario):
Pain and disorders of the human skeletal muscles are one of the most common reasons for medical consultations in the western countries today and there is a great need to improve both the understanding and treatment of several different muscular conditions. Techniques describing the muscle function in vivo are often limited by either their invasiveness or lack of spatial resolution. Electromyography (EMG) is the most common approach to assess the skeletal muscle function in vivo, providing information on the neurological input. However, the spatial resolution is in general limited and there are difficulties reaching deep musculature without using invasive needles. Moreover, it does not provide any information about muscle structure or mechanical aspects. Quantitative ultrasound techniques have gained interest in the area of skeletal muscles and enables non-invasive and in-vivo insight to the intramuscular activity, through the mechanical response of the activation. However, these techniques are developed and evaluated for cardiovascular applications and there are important considerations to be made when applying these methods in the musculoskeletal field. This thesis is based on the work from four papers with the main focus to investigate and describe some of these considerations in combination with the development of processing and analyzing methods that can be used to describe the physiological characteristics of active muscle tissue. In the first paper the accuracy of the Doppler based technique Tissue Velocity Imaging (TVI) was evaluated in a phantom study for very low tissue velocities and the effect of the pulse repetition frequency was considered. The second paper presents a biomechanical model to describe the TVI strain’s dependency on the muscle fiber pennation angle. In the third and fourth papers the intramuscular activity pattern was assessed through the regional tissue deformation by motion mode (M-mode) strain imaging. The activity patterns were analyzed during force regulation and for the effects of fatigue. The work of this thesis show promising results for the application of these methods on skeletal muscles and indicate high clinical potential where quantitative ultrasound may be a valuable tool to reach a more multifaceted and comprehensive insight in the musculoskeletal function. However, the methodological considerations are highly important for the optimized application and further evaluation and development of analyzing strategies are needed.QC 20130516
13
Dokun, Olajide David. "Laser ultrasonic techniques and numerical models for damage and degradation tracking in FRP composites". Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/21486.
Testo completo
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Goldsmith, Abraham Myron. "An Inertial-Optical Tracking System for Quantitative, Freehand, 3D Ultrasound". Digital WPI, 2009. https://digitalcommons.wpi.edu/etd-theses/107.
Testo completoAbstract (sommario):
Three dimensional (3D) ultrasound has become an increasingly popular medical imaging tool over the last decade. It offers significant advantages over Two Dimensional (2D) ultrasound, such as improved accuracy, the ability to display image planes that are physically impossible with 2D ultrasound, and reduced dependence on the skill of the sonographer. Among 3D medical imaging techniques, ultrasound is the only one portable enough to be used by first responders, on the battlefield, and in rural areas. There are three basic methods of acquiring 3D ultrasound images. In the first method, a 2D array transducer is used to capture a 3D volume directly, using electronic beam steering. This method is mainly used for echocardiography. In the second method, a linear array transducer is mechanically actuated, giving a slower and less expensive alternative to the 2D array. The third method uses a linear array transducer that is moved by hand. This method is known as freehand 3D ultrasound. Whether using a 2D array or a mechanically actuated linear array transducer, the position and orientation of each image is known ahead of time. This is not the case for freehand scanning. To reconstruct a 3D volume from a series of 2D ultrasound images, assumptions must be made about the position and orientation of each image, or a mechanism for detecting the position and orientation of each image must be employed. The most widely used method for freehand 3D imaging relies on the assumption that the probe moves along a straight path with constant orientation and speed. This method requires considerable skill on the part of the sonographer. Another technique uses features within the images themselves to form an estimate of each image's relative location. However, these techniques are not well accepted for diagnostic use because they are not always reliable. The final method for acquiring position and orientation information is to use a six Degree-of-Freedom (6 DoF) tracking system. Commercially available 6 DoF tracking systems use magnetic fields, ultrasonic ranging, or optical tracking to measure the position and orientation of a target. Although accurate, all of these systems have fundamental limitations in that they are relatively expensive and they all require sensors or transmitters to be placed in fixed locations to provide a fixed frame of reference. The goal of the work presented here is to create a probe tracking system for freehand 3D ultrasound that does not rely on any fixed frame of reference. This system tracks the ultrasound probe using only sensors integrated into the probe itself. The advantages of such a system are that it requires no setup before it can be used, it is more portable because no extra equipment is required, it is immune from environmental interference, and it is less expensive than external tracking systems. An ideal tracking system for freehand 3D ultrasound would track in all 6 DoF. However, current sensor technology limits this system to five. Linear transducer motion along the skin surface is tracked optically and transducer orientation is tracked using MEMS gyroscopes. An optical tracking system was developed around an optical mouse sensor to provide linear position information by tracking the skin surface. Two versions were evaluated. One included an optical fiber bundle and the other did not. The purpose of the optical fiber is to allow the system to integrate more easily into existing probes by allowing the sensor and electronics to be mounted away from the scanning end of the probe. Each version was optimized to track features on the skin surface while providing adequate Depth Of Field (DOF) to accept variation in the height of the skin surface. Orientation information is acquired using a 3 axis MEMS gyroscope. The sensor was thoroughly characterized to quantify performance in terms of accuracy and drift. This data provided a basis for estimating the achievable 3D reconstruction accuracy of the complete system. Electrical and mechanical components were designed to attach the sensor to the ultrasound probe in such a way as to simulate its being embedded in the probe itself. An embedded system was developed to perform the processing necessary to translate the sensor data into probe position and orientation estimates in real time. The system utilizes a Microblaze soft core microprocessor and a set of peripheral devices implemented in a Xilinx Spartan 3E field programmable gate array. The Xilinx Microkernel real time operating system performs essential system management tasks and provides a stable software platform for implementation of the inertial tracking algorithm. Stradwin 3D ultrasound software was used to provide a user interface and perform the actual 3D volume reconstruction. Stradwin retrieves 2D ultrasound images from the Terason t3000 portable ultrasound system and communicates with the tracking system to gather position and orientation data. The 3D reconstruction is generated and displayed on the screen of the PC in real time. Stradwin also provides essential system features such as storage and retrieval of data, 3D data interaction, reslicing, manual 3D segmentation, and volume calculation for segmented regions. The 3D reconstruction performance of the system was evaluated by freehand scanning a cylindrical inclusion in a CIRS model 044 ultrasound phantom. Five different motion profiles were used and each profile was repeated 10 times. This entire test regimen was performed twice, once with the optical tracking system using the optical fiber bundle, and once with the optical tracking system without the optical fiber bundle. 3D reconstructions were performed with and without the position and orientation data to provide a basis for comparison. Volume error and surface error were used as the performance metrics. Volume error ranged from 1.3% to 5.3% with tracking information versus 15.6% to 21.9% without for the version of the system without the optical fiber bundle. Volume error ranged from 3.7% to 7.6% with tracking information versus 8.7% to 13.7% without for the version of the system with the optical fiber bundle. Surface error ranged from 0.319 mm RMS to 0.462 mm RMS with tracking information versus 0.678 mm RMS to 1.261 mm RMS without for the version of the system without the optical fiber bundle. Surface error ranged from 0.326 mm RMS to 0.774 mm RMS with tracking information versus 0.538 mm RMS to 1.657 mm RMS without for the version of the system with the optical fiber bundle. The prototype tracking system successfully demonstrated that accurate 3D ultrasound volumes can be generated from 2D freehand data using only sensors integrated into the ultrasound probe. One serious shortcoming of this system is that it only tracks 5 of the 6 degrees of freedom required to perform complete 3D reconstructions. The optical system provides information about linear movement but because it tracks a surface, it cannot measure vertical displacement. Overcoming this limitation is the most obvious candidate for future research using this system. The overall tracking platform, meaning the embedded tracking computer and the PC software, developed and integrated in this work, is ready to take advantage of vertical displacement data, should a method be developed for sensing it.
15
Yastrebova, Olga [Verfasser], e Michael [Akademischer Betreuer] Kröning. "Optical flow transducer position tracking for quantitative manual ultrasonic testing / Olga Yastrebova. Betreuer: Michael Kröning". Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2013. http://d-nb.info/1053032455/34.
Testo completo
16
Widman, Erik. "Ultrasonic Methods for Quantitative Carotid Plaque Characterization". Doctoral thesis, KTH, Medicinsk bildteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-192339.
Testo completoAbstract (sommario):
Cardiovascular diseases are the leading causes of death worldwide and improved diagnostic methods are needed for early intervention and to select the most suitable treatment for patients. Currently, carotid artery plaque vulnerability is typically determined by visually assessing ultrasound B-mode images, which is influenced by user-subjectivity. Since plaque vulnerability is correlated to the mechanical properties of the plaque, quantitative techniques are needed to estimate plaque stiffness as a surrogate for plaque vulnerability, which would reduce subjectivity during plaque assessment. The work in this thesis focused on three noninvasive ultrasound-based techniques to quantitatively assess plaque vulnerability and measure arterial stiffness. In Study I, a speckle tracking algorithm was validated in vitro to assess strain in common carotid artery (CCA) phantom plaques and thereafter applied in vivo to carotid atherosclerotic plaques where the strain results were compared to visual assessments by experienced physicians. In Study II, hard and soft CCA phantom plaques were characterized with shear wave elastography (SWE) by using phase and group velocity analysis while being hydrostatically pressurized followed by validating the results with mechanical tensile testing. In Study III, feasibility of assessing the stiffness of simulated plaques and the arterial wall with SWE was demonstrated in an ex vivo setup in small porcine aortas used as a human CCA model. In Study IV, SWE and pulse wave imaging (PWI) were compared when characterizing homogeneous CCA soft phantom plaques. The techniques developed in this thesis have demonstrated potential to characterize carotid artery plaques. The results show that the techniques have the ability to noninvasively evaluate the mechanical properties of carotid artery plaques, provide additional data when visually assessing B-mode images, and potentially provide improved diagnoses for patients suffering from cerebrovascular diseases.Doctoral thesis in medical technology and medical sciences
QC 20160921
17
Siores, E. "Development of a real-time ultrasonic sensing system for automated and robotic welding". Thesis, Brunel University, 1988. http://bura.brunel.ac.uk/handle/2438/5550.
Testo completoAbstract (sommario):
The implementation of robotic technology into welding processes is made difficult by the inherent process variables of part location, fit up, orientation and repeatability. Considering these aspects, to ensure weld reproducibility consistency and quality, advanced adaptive control techniques are essential. These involve not only the development of adequate sensors for seam tracking and joint recognition but also developments of overall machines with a level of artificial intelligence sufficient for automated welding. The development of such a prototype system which utilizes a manipulator arm, ultrasonic sensors and a transistorised welding power source is outlined. This system incorporates three essential aspects. It locates and tracks the welding seam ensuring correct positioning of the welding head relatively to the joint preparation. Additionally, it monitors the joint profile of the molten weld pool and modifies the relevant heat input parameters ensuring consistent penetration, joint filling and acceptable weld bead shape. Finally, it makes use of both the above information to reconstruct three-dimensional images of the weld pool silhouettes providing in-process inspection capabilities of the welded joints. Welding process control strategies have been incorporated into the system based on quantitative relationships between input parameters and weld bead shape configuration allowing real-time decisions to be made during the process of welding, without the need for operation intervention.
18
Winkler, Bryon. "An implementation of an ultrasonic indoor tracking system supporting the OSGI architecture of the ICTA lab". [Gainesville, Fla.] : University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE0000617.
Testo completo
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Maqueira, Benigno. "Robotic seam tracking of weld joints through the use of an ultrasonic sensor : system development and implementation". Thesis, Georgia Institute of Technology, 1986. http://hdl.handle.net/1853/15839.
Testo completo
20
Lilly, Bradford R. "A Novel System for Wireless Robotic Surgery Through the Use of Ultrasonic Tracking Coupled with Advanced Modeling Techniques". University of Toledo / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1333673350.
Testo completo
21
Jayabharath, Kumar Suri. "Sensor systems for positioning and identification in ubiquitous computing". Thesis, Linköping University, Department of Computer and Information Science, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5767.
Testo completoAbstract (sommario):
Technologies for position sensing and identification are important to have in ubiquitous computing environments. These technologies can be used to track users, devices, and artefacts in the physical milieu, for example, locating the position of a cellular phone in av physical environment. The aim of this thesis was to survey and classify available technologies for location sensing and identification.
We have made a literature study on both commercial and research-oriented systems and technologies for use in indoor and outdoor environments. We compared the characteristics of the underlying sensing technologies with respect to physical size, sensing method, cost, and accuracy. We conclude the thesis with a set of recommendations to developers and discuss the requirements on future sensing technologies and their use in mobile devices and environments.
22
Johansson, Sixten. "Navigering och styrning av ett autonomt markfordon". Thesis, Linköping University, Department of Electrical Engineering, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-6006.
Testo completoAbstract (sommario):
I detta examensarbete har ett system för navigering och styrning av ett autonomt fordon implementerats. Syftet med detta arbete är att vidareutveckla fordonet som ska användas vid utvärdering av banplaneringsalgoritmer och studier av andra autonomifunktioner. Med hjälp av olika sensormodeller och sensorkonfigurationer går det även att utvärdera olika strategier för navigering. Arbetet har utförts utgående från en given plattform där fordonet endast använder sig av enkla ultraljudssensorer samt pulsgivare på hjulen för att mäta förflyttningar. Fordonet kan även autonomt navigera samt följa en enklare given bana i en känd omgivning. Systemet använder ett partikelfilter för att skatta fordonets tillstånd med hjälp av modeller för fordon och sensorer.
Arbetet är en fortsättning på projektet Collision Avoidance för autonomt fordon som genomfördes vid Linköpings universitet våren 2005.
In this thesis a system for navigation and control of an autonomous ground vehicle has been implemented. The purpose of this thesis is to further develop the vehicle that is to be used in studies and evaluations of path planning algorithms as well as studies of other autonomy functions. With different sensor configurations and sensor models it is also possible to evaluate different strategies for navigation. The work has been performed using a given platform which measures the vehicle’s movement using only simple ultrasonic sensors and pulse encoders. The vehicle is able to navigate autonomously and follow a simple path in a known environment. The state estimation is performed using a particle filter.
The work is a continuation of a previous project, Collision Avoidance för autonomt fordon, at Linköpings University in the spring of 2005.
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Hoolihan, John Paul Jr School of Biological Earth & Environmental Sciences UNSW. "Biology of Arabian Gulf sailfish". Awarded by:University of New South Wales. School of Biological, Earth and Environmental Sciences, 2005. http://handle.unsw.edu.au/1959.4/20755.
Testo completoAbstract (sommario):
Biological and life history characteristics for a previously unstudied population of sailfish, Istiophorus platypterus, in the Arabian Gulf were investigated. Notable findings include temporal-spatial migration patterns for a genetically isolated population that is threatened by overexploitation. Conventional tagging resulted in 2053 releases and 114 recaptures (5.55%) inside the Gulf. Linear displacement ranged from 2.5 to 697 km, while days at liberty ranged from 17 to 818 days. Dead recoveries in Iranian gillnets account for 88.6% of recaptures. Modeling analyses produced a best estimate of annual survival probability (S) at 0.375 (slope = -0.101, SE = 0.324). Fifteen pop-up satellite archival tags were deployed on sailfish during 2001 - 2002 to track temporal and spatial movements. Extensive data from four tags showed 83.7% of time-at-depth was spent above 10 m with no significant difference (P < 0.05) in diel preference. Depth ranged from 0.0 m to 61.0 m, while temperature ranged from 19.7 ??C to 30.1 ??C. Small-scale movements of eight sailfish were measured using ultrasonic tracking for periods ranging from 3:33 to 53:06 hours. Track distances ranged from 5.5 to 78.5 km, while linear displacement ranged from 4.6 to 37.0 km. Average speed ranged from 0.29 to 0.75 m s-1. Vertical distributions showed 84.3% of time was spent above 10 m depth, even though water temperature showed negligible variation with depth. Mitochondrial DNA comparison of 147 sailfish produced 39 composite haplotypes using eight restriction enzymes. Significant differences occurred in the frequency between population groups inside and outside the Gulf (amova 34.8%, P < 0.01; FST = 0.356), along with evidence of restricted migration between them (average number of migrants, Nm = 0.903). Nine year classes (0-8) were determined from aging analysis of fin spines. Females (n = 50) ranged from 0 to 8 years, while males (n = 34) ranged from 0 to 6 years. Von Bertalanffy growth function indicated rapid growth during the first two years, after which males stabilized and females continued growing to a greater maximum mean length and weight. A comparison of allometric growth between sexes indicated no significant difference between length and other morphometric characters (P ranged 0.135 ??? 0.980).
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Barbosa, Daniel. "Automated assessment of cardiac morphology and function : An integrated B-spline framework for real-time segmentation and tracking of the left ventricle". Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0111.
Testo completoAbstract (sommario):
L’objectif principal de cette thèse est le développement de techniques de segmentation et de suivi totalement automatisées du ventricule gauche (VG) en RT3DE. Du fait de la nature difficile et complexe des données RT3DE, l’application directe des algorithmes classiques de vision par ordinateur est le plus souvent impossible. Les solutions proposées ont donc été formalisées et implémentées de sorte à satisfaire les contraintes suivantes : elles doivent permettre une analyse complètement automatique (ou presque) et le temps de calcul nécessaire doit être faible afin de pouvoir fonctionner en temps réel pour une utilisation clinique optimale. Dans ce contexte, nous avons donc proposé un nouveau cadre ou les derniers développements en segmentation d’images par ensembles de niveaux peuvent être aisément intégrés, tout en évitant les temps de calcul importants associés à ce type d’algorithmes. La validation clinique de cette approche a été effectuée en deux temps. Tout d’abord, les performances des outils développés ont été évaluées dans un contexte global se focalisant sur l’utilisation en routine clinique. Dans un second temps, la précision de la position estimée du contour du ventricule gauche a été mesurée. Enfin, les méthodes proposées ont été intégrées dans une suite logicielle utilisée à des fins de recherche. Afin de permettre une utilisation quotidienne efficace, des solutions conviviales ont été proposées incluant notamment un outil interactif pour corriger la segmentation du VGThe fundamental goal of the present thesis was the development of automatic strategies for left ventricular (LV) segmentation and tracking in RT3DE data. Given the challenging nature of RT3DE data, classical computer vision algorithms often face complications when applied to ultrasound. Furthermore, the proposed solutions were formalized and built to respect the following requirements: they should allow (nearly) fully automatic analysis and their computational burden should be low, thus enabling real-time processing for optimal online clinical use. With this in mind, we have proposed a novel segmentation framework where the latest developments in level-set-based image segmentation algorithms could be straightforwardly integrated, while avoiding the heavy computational burden often associated with level-set algorithms. Furthermore, a strong validation component was included in order to assess the performance of the proposed algorithms in realistic scenarios comprising clinical data. First, the performance of the developed tools was evaluated from a global perspective, focusing on its use in clinical daily practice. Secondly, also the spatial accuracy of the estimated left ventricular boundaries was assessed. As a final step, we aimed at the integration of the developed methods in an in-house developed software suite used for research purposes. This included user-friendly solutions for efficient daily use, namely user interactive tools to adjust the segmented left ventricular boundaries
25
Lourenco, de Oliveira Philippe. "Conception de solutions technologiques et d’outils pour le traitement d’organes par ultrasons focalisés guidés par IRM". Thesis, Bordeaux 1, 2009. http://www.theses.fr/2009BOR13963/document.
Testo completoAbstract (sommario):
Le traitement par ultrasons focalisés (HIFU) associé au contrôle par l’Imagerie de Résonance Magnétique (IRM) est une méthode prometteuse pour les thermothérapies de type non invasive sur patient en respiration libre. Une solution technologique pour l’amélioration du transfert de puissance électrique vers le transducteur ultrason autour d’un système d’adaptation d’impédance ajustable a été réalisée. Un chapitre a été consacré à la caractérisation des transducteurs par la mesure et simulation du champ acoustique spatial. Les deux derniers chapitres, concernent le développement d’outils logiciels autour de l’IRM. Une méthode de caractérisation des paramètres thermiques des tissus chauffés, utile pour une qualité d’asservissement de température optimale, a été développée. Enfin, une étude de faisabilité a été menée sur le couplage des mesures de déplacements rapides par ultrasons avec les mesures robustes fournies par IRM, ceci pour un meilleur suivi du mouvement des organes mobilesTreatment with Focused Ultrasound (HIFU) combined with Magnetic Resonance Imaging (MRI) control is a promising method for xxx thermotherapy on patient free breathing. A technological solution for improving the transfer of electrical power to the ultrasonic transducer around a adjustable impedance matching system has been achieved. A chapter was devoted to the characterization of transducers acoustic field by measure and simulation. The last two chapters concern the development of software tools around the MRI. A method to determinate the thermal parameters of tissues heated, useful to compute an optimal temperature control was developed. Finally, a feasibility study has been conducted on the combination of fast ultrasound motion estimation with robust MRI motion estimation, this to improve the quality of the motion tracking
26
Banker, Christian John. "Interactive Training System for Medical Ultrasound". Digital WPI, 2009. https://digitalcommons.wpi.edu/etd-theses/164.
Testo completoAbstract (sommario):
Ultrasound is an effective imaging modality because it is safe, unobtrusive and portable. However, it is also very operator-dependent and significant skill is required to capture quality images and properly detect abnormalities. Training is an important part of ultrasound, but the limited availability of training courses presents a significant hindrance to the use of ultrasound being used in additional settings. The goal of this work was to design and implement an interactive training system to help train and evaluate sonographers. The Interactive Training System for Medical Ultrasound is an inexpensive, software-based training system in which the trainee scans a lifelike manikin with a sham transducer containing a 6 degree of freedom tracking sensor. The observed ultrasound image is generated from a pre-stored 3D image volume and is controlled interactively by the sham transducer's position and orientation. Based on the selected 3D volume, the manikin may represent normal anatomy, exhibit a specific trauma or present a given physical condition. The training system provides a realistic scanning experience by providing an interactive real-time display with adjustable image parameters such as scan depth, gain, and time gain compensation. A representative hardware interface has been developed including a lifelike manikin and convincing sham transducers, along with a touch screen user interface. Methods of capturing 3D ultrasound image volumes and stitching together multiple volumes have been evaluated. System performance was analyzed and an initial clinical evaluation was performed. This thesis presents a complete prototype training system with advanced simulation and learning assessment features. The ultrasound training system can provide cost-effective and convenient training of physicians and sonographers. This system is an innovative approach to training and is a powerful tool for training sonographers in recognizing a wide variety of medical conditions.
27
Ormachea, Quispe Juvenal. "Evaluation of shear wave speed measurements using crawling waves sonoelastography and single tracking location acoustic radiation force impulse imaging". Master's thesis, Pontificia Universidad Católica del Perú, 2015. http://tesis.pucp.edu.pe/repositorio/handle/123456789/6195.
Testo completoAbstract (sommario):
Many pathological conditions are closely related with an increase in tissue sti ness.
For many years, experts performed manual palpation in order to measure elasticity changes, however, this method can only be applied on superficial areas of the human body and provides crude sti ness estimation. Elastography is a technique that attempts to characterize the elastic properties of tissue in order to provide additional and useful information for clinical diagnosis. For more than twenty years, di erent research groups have developed various elastography modalities with a strong interest for quantitative images during the last decade.
Recently, comparative studies among di erent elastographic techniques have been performed in order to better characterize biomaterials, to cross-validate several shear wave elastographic modalities and to study the factors that influence their precision and accuracy.
This comparison works may contribute to achieve standardization in quantitative elastography and their use in commercial equipment for their application in human patients. However, there is still a limited literature in the field of quantitative elastography modalities comparisons.
This thesis focuses on the comparison between two elastographic techniques: crawling
wave sonoelastography (CWS) and single tracking location-acoustic radiation force impulse (STL-ARFI). The comparison shows the estimation of the shear wave speed (SWS), lateral resolution, contrast and contrast-to-noise ratio (CNR) in homogeneous and inhomogeneous phantoms using both techniques. The SWS values obtained with both modalities are validated with mechanical measurements that are considered as ground truth. The SWS results for the three di erent homogeneous phantoms (10%, 13%, and 16% gelatin concentrations), show good agreement between CWS, STL-ARFI and mechanical measurements as a function of frequency. The maximum accuracy errors obtained with CWS were 2.52%, 1.63% and 2.26%. For STL-ARFI, the maximum errors were 6.22%, 5.63% and 4.08% for the 10%,13% and 16% gelatin phantom respectively. For lateral resolution, contrast and CNR estimated in the inhomogeneous phantoms, it can be seen that for vibration frequencies higher than 340 Hz, CWS presents better results than the obtained with STL-ARFI using distances between the push beams ( x) higher than 4 mm. However, using these vibration frequencies will not be feasible for in vivo tissues due to attenuation problems. It that sense, for lower vibration frequencies than 300 Hz and x among 3 mm and 6 mm, comparable lateral resolution, contrast and CNR was obtained. Finally, the results of this study contribute to the data currently available for comparing elastographic techniques. Moreover, the methodology implemented in this document may be helpful for future standardization
for di erent elastographic modalities.Tesis
28
Poulsen, Carsten. "Development of a positioning system for 3D ultrasound". Link to electronic thesis, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-101805-180813/.
Testo completo
29
Chanel, Laure-Anaïs. "Assistance à la thérapie par ultrasons focalisés de haute intensité (HIFU) : compensation des mouvements physiologiques par asservissement sur images ultrasonores". Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAD003/document.
Testo completoAbstract (sommario):
La thérapie par ultrasons focalisés de haute intensité (HIFU) est une méthode non invasive et non ionisante pour l’ablation des tumeurs solides. Cependant, le mouvement des organes intra-abdominaux, dû principalement à la respiration, empêche les ultrasons de cibler correctement la tumeur. Dans ce contexte, un système HIFU robotisé tout-en-un qui compense le mouvement en temps réel pendant le traitement par HIFU a été développé. À cet effet, un système d’asservissement ultrasonore fonctionnant à une fréquence de 20 Hz, basé sur une méthode rapide de suivi du speckle ultrasonore pour l’estimation du mouvement, a été conçu. Il utilise une séquence d’alternance imagerie/exposition HIFU, dont le rapport cyclique est de 80 %, afin d’éviter les interférences d’ondes. Le système HIFU robotisé a été testé sur un fantôme imitant les tissus soumis à des mouvements sinusoïdaux 1D et 2D. Il en résulte une réduction de mouvement de plus de 80 % en 1D pour une fréquence de 0,25 Hz et de 90 % en 2D pour une fréquence de 0,1 Hz. Toutefois, il n' a pas pu être observé un effet significatif de la compensation du mouvement sur les lésions induites par HIFUHigh Intensity Focused Ultrasound (HIFU) therapy is a non-invasive and non-ionizing method for ablation of solid tumors. However, intra-abdominal organ motion, mainly due to breathing, is a major hurdle for proper targeting of the tumor. In this context, an all-in-one HIFU robotized system with motion compensation in real-time during HIFU treatment was developed. To this aim, an ultrasound visual servoing working at a frequency of 20 Hz, relying on a fast ultrasonic speckle tracking method for motion estimation, was designed. It uses an interleaved imaging/HIFU sonication sequence, with duty cycle of 80 %, in order to avoid wave interferences. The robotized HIFU system was tested on a tissue mimicking phantom undergoing a 1D and a 2D sinusoidal motion. As a result, motion reduction of more than 80 % in 1D for a frequency of 0.25 Hz and more than 90 % in 2D for a frequency of 0.1 Hz was obtained. However, it couldn't be observed a significant effect of motion compensation on the lesions induced by HIFU
30
Greaves, Danielle Kathleen. "Désadaptations cardiovasculaires à la microgravité : techniques avancées pour améliorer la mesure et l'évaluation du risque cardiovaculaire induit par les vols spatiaux pour les équipages de longue durée Effects of exercise countermeasure on myocardial contractility measured by 4D speckle tracking during a 21-day head-down bed rest Cardiac and arterial structure and functional changes after four days of dry immersion with and without thigh cuffs Effect of thigh cuff on venous flow redistribution during 4 days in dry immersion". Thesis, Normandie, 2019. http://www.theses.fr/2019NORMC433.
Testo completoAbstract (sommario):
L'objectif était de quantifier les modifications de la contractilité cardiaque au cours d’un bedrest de 21 jours (HDBR) par la methode speckle tracking 4D et de déterminer si la contre-mesure « exercice » était capable de préserver cette contractilité cardiaque. Les méthodes traditionnelles 2D ne mesurent qu'une variation de la taille du ventricule de la systole à la diastole et ne suivent pas la cinetique des mouvements de contractilité à l’interieur de la paroi. De plus l’echographie 2D ne permet d’acceder qu’a la contractilite longitudinale globale par la mesure de la distance Apex-Valve mitrale. Le suivi des mouvements des speckles (points singuliers a l’interieur du myocarde) en 4D montre que la contractilité radiale diminuée signifcativement pendant le HDTBR chez les sujets témoins alors qu’elle est conservée dans le groupe exercice. Par contre la contractilité longitudinale n’est pas affectée dans aucun des 2 groupes. Bien sûr, l'IRM pourrait fournir des données similaires, mais il n’est pas possible à ce jour d’imaginer avoir une IRM a bord de l’ISS dans un futur proche. A la suite de ces resultats nous avons mis au point un algorithme de traitement des video cardiaque qui permet d’acceder a la contractilite radiale et longitudinale en vol (prog Vasc-Aging en cours) .L’objectif de l’experimentation était de montrer que quatre jours en immersion seche suffisaient pour realiser un transfert liquidien important vers les régions céphaliques comparable à celui observé en vol spatial. Notre protocole consistait donc a mesurer les volume veineux au niveau cervical cerebral et porte au debut de la periode en immersion (a 2h) puis a 4 jours d’immersion. Compte tenu des problemes engendrés par ce transfert liquidien en vol nous avions proposé de tester la capacité des brassarts de cuisse a reduire l’amplitude du transfert veineux. Les résultats montrent que l’immersion provoque un transfert de sang veineux au niveau cervical maximal à 2H et que les Brassarts de cuisse reduisent signifcativement ce transfert dans cette phase precoce. Par contre a 4 jours d’immersion l’amplitude du transfert sanguin est considerablement diminuée (bien que toujours presente) et les brassarts de cuisse n’ont pas d’effet visible à ce moment-là. En fait le volume plasmatique decroit significativement à la fin du premier jour (env 20%) des lors la masse de sang deplacées vers la tete par l’immersion est insuffisante pour generer une stase importante au niveau cervical comme à 2h d’immersion. Pour cette meme raison la vitesse dans les veines cerebrales n’est pas augmentée à 4 jours d’immersion contrairement à ce qu’on avait observé à 2h d’immersion lors d’une precedente etude. Donc le modele immersion seche est un modele pour etudier les transferts liquidiens en microgravité mais seulement en debut de phase d’immersion. Sur cette période de temps, les Brassarts de cuisse ont bien un effet protecteur pour les organes de la zone cephaliqueObjective: to evaluate functional myocardial contractility after 21 days of head-down bed rest (HDTBR) in sedentary control (CON) or with a resistive vibration exercise (RVE) countermeasure (CM) applied, by using 4D echocardiographic (4D Echo) imaging and speckle tracking strain quantification.Methods: Twelve volunteers were enrolled in a crossover HDTBR design, and 4D Echo was performed in supine position (REST) at BDC-2 and at R+2, and in -6° HDTBR (on day 18), and also during the first and the last minute of the 80° head-up step of Standard Measures tilt test, performed at both BDC-2 and R+2. Radial (Rad-Str), longitudinal (Lg-Str) and twist (Tw-Str) strain were measured by 4D speckle tracking, as well as left ventricle diastolic volume (LVDV) and mass (LVmass).Results: On day 18: in the CON group, LVDV and LVmass were reduced (p<0.05), the Rad-Str decreased (p<0.05) and Tw-Str showed a tendency to increase (p< 0.11), with no changes in Lg-Str. In RVE group, LVDV and LV mass, as well as all the strain parameters remained unchanged.On R+2: in the CON group, LVDV and LVmass were not recovered in all subjects compared to pre-HDTBR (p<0.08), Rad-Str was still decreased (p<0.05), while Tw-Str tended to increase (p<0.09). These parameters remained unchanged in the RVE group.Tilt 80°: Rad-Str and Lg-Str values at 80° tilt were similar post HDT in both groups.Conclusion: 4D Echo and speckle tracking analysis showed that in the CON group, Rad-Str decreased concomitant with LVmass and LVDV with HDTBR, but this observation did not support the hypothesis that this HDTBR induced remodelling or a muscle atrophy. RVE acted to preserve both LVmass, LVDV and contractility during HDTBR, thus proving its effectiveness to this aim. Nevertheless, the significant HDTBR-induced changes observed in the CON group had only a limited effect on the cardiac contractile response as observed during post HDTBR tilt test. The level of contractility at 80° Tilt position was not affected neither by HDTBR nor by RVE CM.Purpose: The objective was to quantify the venous redistribution during a 4-day dry immersion (DI) and evaluate the effect of thigh cuffs.Methods: The study included 9 control (Co) and 9 subjects wearing thigh cuffs during daytime hours (CU). Ultrasound images were collected Pre DI, on the fourth day in the morning (D4 AM) and on the fourth day in the afternoon (D4 PM), to assess the following outcome variables: left ventricle dimension, stroke volume, and ejection fraction (LVD, SV, EF), jugular vein volume (JV), portal vein dimension (PV), middle cerebral vein velocity (MCVv). An additional measure of JV dimension was performed on the first day after having worn the cuffs for two hours (D1 2H).Results: The JV volume increased significantly from Pre to D1 2H in both groups, but increased more in the Co compare to the CU subjects (Co: 0,27+/0.15cm3 to 0.94+/-0;22 cm3;P<0.01 CU: 0,32+/-0.13 cm3 to 0.64+/-0.32 cm3 P<0.042).At D4 AM no difference was found between the two treatment groups for any of the parameters listed above.Stroke volume and EF decreased from Pre (SV:111+/-23cm3 to 93+/-24 cm3 p<0.05; EF:0.66+/-0.07 to 0.62+/-0.07 p<0.05). JV volume was slightly, but significantly increased (Co: 0.47+/-0.22cm3 CU:0.35+/-014cm3 P<0.05), while MCVv and PV remained unchanged from Pre DI. From D4 AM to PM these parameters did not show any significant change.Conclusion: The results confirm that DI induces, during the first 2-3 h, a significant cephalic fluid shift as observed in spaceflight. During this early phase the thigh cuffs reduced the amplitude of the fluid shift towards the head, but after 4 days in DI there was only a slight memory (residual) effect of DI on the jugular volume and no residual effect of thigh cuffs
31
Porras, Pérez Antonio Reyes. "Multi-cue image integration for cardiac tissue characterization". Doctoral thesis, Universitat Pompeu Fabra, 2015. http://hdl.handle.net/10803/296796.
Testo completoAbstract (sommario):
Una caracterización precisa y completa del tejido cardíaco es esencial para el diagnóstico y tratamiento de problemas cardíacos. Para caracterizar la función cardíaca desde diferentes perspectivas, en la práctica clínica, se adquieren grandes cantidades de datos de distinta naturaleza sobre un mismo paciente, proporcionando información útil para la evaluación del corazón. Aunque los distintos datos obtenidos de cada paciente se suelen analizar por separado para evaluar la función cardíaca desde diferentes perspectivas, la combinación efectiva de esta información heterogénea podría ser útil para tener una mejor visión de la anatomía y la función cardíaca. El objetivo principal de esta tesis es el desarrollo de métodos para integrar imágenes e información de distinta naturaleza para una caracterización del tejido cardíaco más completa y precisa.An accurate and complete cardiac tissue characterization is essential to diagnose and treat heart problems. To characterize cardiac function from different perspectives, large amounts of data of different nature from the same patient are acquired in clinical practice, providing information that is useful for heart assessment. Although the different data obtained from each patient are often analyzed separately to assess cardiac function from different perspectives, the effective combination of this heterogeneous information may be useful for a better insight into heart anatomy and function. The main objective of this thesis is to develop methods to integrate images and information of different nature for a more complete and accurate cardiac tissue characterization.
32
He, Jia-Hong, e 何嘉浤. "Ultrasonic Renal-Stone Tracking with Mesh Regularization". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/12954007746159106870.
Testo completoAbstract (sommario):
碩士臺灣大學
電機工程學研究所
95
The efficacy of Extracorporeal Shock Wave Lithotripsy (ESWL) depends greatly on the capability to focus shock waves on renal stone. To achieve automatic focusing on moving target, the target must be under tracking. A mesh-based block matching algorithm is proposed for renal stone tracking using ultrasound image sequence. Since multiple targets are tracked together, the mesh-based tracking algorithm can provide a function of contextual regularization for solving the target missing and image degradation problems in renal stone tracking. Recorded ultrasound images of kidney during ESWL treatment are modified for demonstrating the capability of this algorithm. We regard the soft tissue of the body as elastic in order to analyze the relationship of stress, strain, deformable energy and displacement. On the basis of the optimal design, we also define the initial displacement of block-matching to minimum the function of matching error energy and the deformable energy by displacement vector to solve the optimal value of displacement of mesh grid nodes. Therein, we figure out the stiffness matrix of deformable energy by finite element method. In order to simplify the calculation, we choose a regular quadrilateral element as the mesh model to achieve the tracking of real time. According to the optimal design, we amend the performance of block-matching to avoid the damage of renal caused by stone breakers.
33
Lee, Min-Kei, e 李閔凱. "Binocular Tracking with the Application of Ultrasonic Sensors". Thesis, 2001. http://ndltd.ncl.edu.tw/handle/77876435756801758043.
Testo completoAbstract (sommario):
碩士國立成功大學
機械工程學系
89
A calibration method is conventionally used by a visual servo system to calculate the depth of an object. However, tracking a 3D moving object typically involves problems in calibration, such as an inaccurate calibration point or difficulty in carrying out real-time tracking. This thesis accordingly uses ultrasonic sensors in conjunction with the visual servo system to directly measure the depth of the object. This study proposes an image-based visual servo control method, which integrates the kinematics of both the robotic binocular head and cameras with the dynamics of the binocular head to obtain an image-based dynamic equation. The fuzzy sliding mode control algorithm is applied to the image-based dynamic equation using the ultrasonic sensors to directly measure the depth of the object. In image processing, the object location is first, roughly determined, before more complex image processing is locally performed, to reduce the time taken in the processing. An attention window is estimated to mark the 3D moving object: the size of the window can grow or shrink to follow the size of the object. A Kalman filter is used to predict the trajectory of the object. Finally, two experiments based on the multiple-sensor binocular head are undertaken to verify the theoretical results. The experiments include active visual tracking of a stationary and moving object.
34
Chen, Yi-Ling, e 陳奕伶. "Resonance-Tracking Relay-Feedback Drive of Ultrasonic Transducer". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/86644387244612735513.
Testo completoAbstract (sommario):
碩士國立中山大學
電機工程學系研究所
104
This thesis utilizes the relay feedback approach to designing a resonance- tracking driver for ultrasonic transducers of different frequencies ranging from 20 kHz to 60 kHz. The driver connected with the transducer in a feedback loop constitutes a relay feedback system, which automatically oscillates and generates sinusoidal driving voltage right at the targeted resonant frequency of the transducer, thereby achieving better transducer efficiency. The driver mainly consists of an FPGA and a class-D power amplifier. The contribution of this thesis is to design the algorithms on the FPGA. The algorithms include a tunable bandpass filter, a tunable delay, and an optimal pulse width modulator, which together make the relay feedback driver more intelligent and more precise.
35
CHANG, YU-CHUAN, e 張佑全. "Design of an Ultrasonic Frequency Tracking and Driving System". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/c7av63.
Testo completoAbstract (sommario):
碩士國立虎尾科技大學
電機工程系碩士班
107
This paper proposes a set of ultrasonic control drive system with FPGA as the core. The FPGA contains digital hardware module written by hardware description language and 32-bit Nios II processor synthesized by FPGA internal logic gate. We conduct system design in FPGA internal by using to integrate 32-bit processor and digital hardware module. The developed approach is also known as System on Programmable Chip (SOPC) technology. In the process of tracking the frequency of the system, we detect the actual working parameters of the ultrasonic oscillator in real time. We aim these parameters to handle and then use the PID control model to compensate the phase in order to achieve the function of frequency tracking control. The user control interface use the LabVIEW graphical programming compilation platform which developed from National Instrument Company and it can design a set of perfect operation interface, and to display the relevant information of ultrasonic drive on the interface in real time to provide operators for analysis. After the system is completed, we test three kinds of ultrasonic oscillators with different resonance frequency intervals. The system can indeed lock the frequency to the optimal point in time and using laser displacement meter through KEYENCE Company to measure the physical vibration amplitude of the ultrasonic oscillator.
36
Lin, Chi-yi, e 林季誼. "Muscular Motion Tracking from 3D and 4D Ultrasonic Image Sequences". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/36325487481835375838.
Testo completoAbstract (sommario):
碩士國立成功大學
資訊工程學系碩博士班
96
The quantitative evaluation of muscular motion is an important index for rehabilitation biomechanics. For the clinical applications on 3D (2D+t) and 4D (3D+t) ultrasonic image sequences respectively, we propose two distinct multi-feature block-matching-based tracking methodologies to estimate muscular motion. The proposed multi-feature block matching methods in multilevel frame work achieve high accuracy and spatial adaptability through considering image intensity, motion velocity, neighbor relativity and selected features. By using multiple selected features, the discriminating region can be determined and provides a confident motion reference for homogeneous region tracking to overcome the motion ambiguity, which the traditional correlation coefficient measurement is extremely suffered from. In 3D motion tracking, the problem of region homogeneity can be handled by the proposed multi-feature block matching in multi-template framework combined with good discriminative neighbor reference and Kalman prediction. To quantify motion of borderless musculature from 4D image sequences, the end of fascia is chosen as target and tracked by multilevel multi-feature block matching with sectional adjustment and drift correction on a muscular motion model. The tolerance for image fuzziness and tissue deformation at low frame rate is effectively increased in the 4D estimation. In the experimental results, the accuracy in both methods is validated from in vivo musculoskeletal ultrasonic image sequences by comparing the results with the doctor-defined ground truth. This study can be applied to clinical diagnosis, such as sport injuries.
37
You, Yi, e 游. 翼. "Design and Implementation of Ultrasonic Driver with Resonant Frequency Tracking". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/vbs22f.
Testo completo
38
Lin, Kuan-Hung, e 林冠宏. "Single Object Tracking Using Multiple Ultrasonic Sensors and Kalman Filtering Techniques". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/3zw6h2.
Testo completoAbstract (sommario):
碩士國立交通大學
電控工程研究所
101
This thesis realizes 2D coordinate localization and tracking of single object on a 59-centimeters-long and 32.4-centimeters-wide large panel based on the principle of ultrasonic range measurement. There are 1 ultrasonic transmitter and 5 receivers equipped on the edge of the panel. The time-of-flight (TOF) from each channel is first derived and the target coordinate is then obtained. TOF estimation is inaccurate due to shape distortion of echoes waveform, which is caused by attenuation during propagation and also varies with target type, size, location, and orientation. A new method of TOF is presented to solve the above problem. This method provides a more accurate and steady TOF estimation by fitting the double exponential model on the reasonable region of envelope using Newton-Ralphson optimization. An Extended Kalman Filter is also designed to estimate the target coordinate inherently accounting the interference and outlier issue of the derived TOF, and effectively reduces the disturbance to target localization in critical measurement condition. The system performance was assessed through experimental evaluation of several scenarios, including localization of stationary marker pen, stationary human’s finger, and tracking on moving human’s finger.
39
Tsai, Hsin-Chuan, e 蔡信全. "Feasibility Study of Indirect Tumor Localization with Ultrasonic Image Tracking System". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/mrv396.
Testo completoAbstract (sommario):
碩士國立臺北科技大學
機械工程系機電整合碩士班
106
In the study, we developed a tumor motion model to detect the tumor position in the lung with real-time ultrasound. The tumor motion model was made using the Ultrasound Image Tracking Algorithm (UITA) with a 4-Dimensional Planning Computed Tomography (4DCT). This method could be applied to radiotherapy about the tumor position compensation technology. In the experiment, we made the three different tumor motion models before the tracking error verification experiment. We made the tumor motion models by the 4DCT. The verification experiment used the Cone Beam Computed Tomography (CBCT). In the validation experiment, the each tumor motion model did five signal sports (four pre-recorded human respiratory signals and one Sin wave). The tumor motion model was created by using UITA to monitor the superior-inferior (SI) trajectory of the diaphragm and using 4DCT to monitor the tumor in SI and medial-lateral (ML) at the same time. The model parameter include center position, amplitude ratio, and phase. The tracking error verification experiment was compare the estimated tumor trajectories and the real tumor trajectories. The estimated tumor trajectories was the UITA uses model transformations to predict tumor position in SI and ML. The actual tumor trajectories was CBCT records the actual tumor position. The CBCT image is record the tumor position in the phantom. The ultrasonic image records the diaphragm position. The diaphragm displacement is converted into the tumor displacement by the prior tumor motion model. About 90 seconds of simultaneous acquisition of CBCT and UITA were analyzed. The error parameter analyze in the most error model. The phase error deviation does not exceed 12% of the length of the respiratory cycle. The feasibility of using ultrasound with 4DCT tumor motion model to track tumor movements in SI and ML directions was confirmed. The error results show that the tracking error is better than the body surface tracking, but this error must consider the error of the CBCT technique. The tracking effect is good in the different respiratory conditions.
40
TA, LONG HUNG, e 謝龍興. "Target tracking Using Multiple Ultrasonic Sensors and Constrained Kalman Filter Algorithm". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/29870933951815896825.
Testo completoAbstract (sommario):
碩士國立交通大學
電控工程研究所
103
This thesis deals with coordinate localization and tracking of single object in the three-dimensional space based on the principle of ultrasonic range measurement. Due to the requirement of localization application in three-dimensional space, our model consists of 1 ultrasonic transmitter and 5 receivers equipped on the edge of the panel. The time-of-flight (TOF) from each channel is firstly derived and then the target coordinate is obtained. TOF estimation is inaccurate due to shape distortion of echoes waveform, which is caused by attenuation during propagation and also varies with target type, size, location, and orientation. A method of TOF estimation for the above problem is presented. This method provides an accurate and steady TOF estimation by fitting the double exponential model on the reasonable region of envelope using Newton-Raphson optimization. A Constrained Extended Kalman Filter is also designed to estimate the target position inherently accounting the interference and outlier issue of the derived TOF, and effectively reduces the disturbance to target localization in critical measurement condition. The system performance was assessed through experimental evaluation of several scenarios, including localization of stationary marker pen, stationary human’s finger, and tracking on moving human’s finger. Index terms: Range-difference, Localization, Sensor array, Constrained Extended Kalman Filter.
41
"An ultrasonic position detecting system for motion tracking in three dimensions". Tulane University, 1993.
Cerca il testo completoAbstract (sommario):
A real-time, ultrasonic position detection instrument has been developed, yielding accuracy of the order of millimeters over an operating volume of several cubic meters. The ultrasonic ranging system consists of a transmitter mounted on the tracked target and four or more stationary receivers. An iterative, weighted least squares algorithm was developed to fuse one dimensional distance measurements. Triangulation calculations, to determine the transmitter's coordinates in space, utilize a temperature estimated speed of sound. Position information obtained by sensor fusion was used to provide adjustable windows on time of flight measurements and thus eliminate malfunctioning sensors A novel hardware level method was developed to improve range, robustness, and accuracy of ultrasonic ranging systems. Peak detection is combined with phase measurement to accurately determine the time-of-flight of the transmitted signal. An automatic gain controller taking feedback from the level of the peak of the received signal is used to increase the working range of the unit, and to attenuate signals resulting from undesirable reflections The factors limiting the reliability and accuracy of a three dimensional ultrasonic ranging system were investigated. It was determined that misalignment between transducers contributes the largest position errors. The phase shifts of the acoustic wave were experimentally mapped in three dimensional space. It was also verified that temperature effects on the speed of sound are a major source of ranging errors A prototype was constructed, and a three dimensional experiment was performed on a target moving along a complex path in an un-controlled laboratory environment. The resolution of the instrument was shown to be within $\pm$0.5 mm in each coordinate direction, given a redundant set of seven functional receivers. The absolute accuracy of the unit was approximately 2.5 mm in each coordinate direction. The identification and suppression of malfunctioning or occluded receivers were successfully accomplished. The position update rate was approximately 5 Hzacase@tulane.edu
42
Lee, Wei-Ning, e 李維寧. "Efficient Speckle Tracking Technique and Its Applications in Ultrasonic Breast Imaging". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/76105995767939930845.
Testo completoAbstract (sommario):
碩士國立臺灣大學
電機工程學研究所
91
Speckle tracking is an important technique in ultrasonic imaging. It is used to estimate the motion (displacement) between two images and the estimation accuracy determines performance various speckle tracking based imaging methods. Unfortunately, speckle tracking is computationally intensive. This limits its applications in clinical situations. Hence, how to improve the computational efficiency is a key issue for the speckle tracking technique. In this paper, an efficient speckle tracking algorithm is proposed for motion estimation in ultrasonic imaging. Speckle tracking involves a matching process and a searching process. The matching process is based on a Block Sum Pyramid algorithm that reduces the computational complexity based on a pyramid structure. The searching process, on the other hand, is based on a multilevel search strategy that greatly improves the computation speed by reducing the number of blocks needed be compared. Both simulated speckle images and clinical breast images were used to test the performance of the proposed algorithm. The results show that the computation efficiency is improved by up to a factor of five over the conventional approach. This new speckle tracking algorithm is also applied to the strain compounding technique for speckle reduction. With the improvement in the efficiency of strain compounding, other related researches, such as tumor contour extraction and feature selection, are also performed for breast imaging.
43
Sheng-HanHo e 何昇翰. "Integration of Ultrasonic and MEMS Sensors to Automatic Mobile Vehicle Tracking Applications". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/80546069941714431434.
Testo completoAbstract (sommario):
碩士國立成功大學
工程科學系碩博士班
100
The goal of this thesis is to design an automatic mobile vehicle tracking function, using a micro-controller (iD6800) as the control kernel. The micro-controller uses PWM to control a DC motor, which makes the front wheel rotation to go forward, and changes the angle of the rear wheel by adjusting the step motor to obtain the functions of moving and turning. The sensor uses a gyroscope to know the turning movement of the user and the automatic mobile vehicle, and then the gyroscope uses the integral and least square methods to get the angle of turning. The ultrasonic range finder on the automatic mobile vehicle uses the TOF algorithm to calculate the offset angle and distance from the user. The automatic mobile vehicle can aim at the user using the step motor and maintain a specific distance between the user and vehicle. The communication between the user and the automatic mobile vehicle is carried out through ZigBee (UZ2400). The user is not required to wear any specific clothes or be in any special environment. As a result, it can overcome problems caused by the influence of sunlight when using a camera.
44
Li, Wan-Chen, e 李宛蓁. "Automatic resonance frequency tracking driver for ultrasonic transducers using a power meter". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/x3yvdd.
Testo completoAbstract (sommario):
碩士義守大學
生物醫學工程學系
104
The Current research relates to ultrasound probes, which according to their application use different frequencies. In general, driving an ultrasound probe must find a suitable way to manually adjust the operating frequency of the probe, but it’s not convenient and accurate. However, in a suitable operating frequency, its power will become higher. Therefore, in this study, we designed a system that can adjust to a suitable and accurate operating frequency automatically. In this study, we developed a function generator using an AD5930 which can produce continuous or burst waveforms. The use of burst waveforms can prevent damage caused by overheat. The output signal is then fed to the inverter to adjust the signal amplitude according to the power supply voltage and drive the ultrasound transducer. A C++ produced software was used to upload parameters to an Arduino UNO microcontroller board so that it can program the AD5930 burst waveform generator to adjust the parameters of the output signal such as the frequency and the burst time. Using this hardware and software concept applied on different ultrasound transducers, we expect to expand the application of ultrasound transducers in the biomedical field. An Arduino microcontroller combined with the AD5930 circuit produces output digital and/or analog signals with stable frequency. The user can easily and conveniently adjust to a desired fixed output frequency or set an increasing sweep frequency. This type of device could be used in various ultrasonic probe applications.
45
Chi, Chen Shih, e 陳世麒. "Intelligent Control for The Precision Position Tracking of Linear Ultrasonic Motor Drive System". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/57790394010892280051.
Testo completoAbstract (sommario):
碩士大葉大學
機械與自動化工程學系
102
This thesis develops an adaptive fuzzy sliding-mode control (AFSMC) for the trajectory tracking of linear ultrasonic motor drive system (LUMDS). The LUMDS are not only highly nonlinear and time-varying systems, but also have to suffer from uncertainties in their dynamics, such as hysteresis, payload variation, and nonlinear friction. It is difficult to find the traditional control method for the precise tracking of the LUMDS. Firstly, a fuzzy logic system (FLS) was used to estimate the overall uncertainties of the LUMDS. Based on FLS, a sliding-mode controller (SMC) was derived to suppress the effects of uncertainties and approximation errors. Moreover, adaptive algorithms for AFSMC parameters are derived from the Lyapunov synthesis approach, thus the stability and robustness of the overall control system are guaranteed. The main idea of the proposed method is to exploit their advantages of the SMC with robust characteristics and the adaptive FLS with online learning ability. The experimental setup is comprised by a host PC, a servo control board (MRC-6810), a linear optical encoder, a linear ultrasonic motor, and an ultrasonic motor driver (AB1A). The Matlab and Visual C++ were used to develop algorithms for the simulations and experiments of the LUMDS. Finally, simulations and experiments were performed using a practice LUMDS to demonstrate the effectiveness of the proposed control methodology.
46
Lu, Chung-Che, e 呂仲哲. "A Study of Inductive Power Transfer Ultrasonic Vibration Assisted Spindle With Resonance Frequency Tracking". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/98846340329617279959.
Testo completoAbstract (sommario):
碩士國立中興大學
機械工程學系所
101
In this paper, we developed a resonant tracking frequency system to solve the resonance frequency drift phenomenon . Due to the inductive power transmission of ultrasonic vibration aided spindle, tool abrasion , cutting feed and inductive power transfer system overheat, all of these will make the resonance frequency drift shift, it might affect the tool amplitude doesn''t stay at the optimal cutting state will affect the machining quality and tool life and so on. In ultrasonic vibration aided spindle design use the finite element analysis for simulate to get tool holder of ultrasonic vibration aided spindle and the best inductive structure. This paper we proposed the compensation circuit which can compensate the inductive power leakage generated by transmission phenomenon. In the system design, the feedback voltage was get from resonant circuit, at the last feedback voltage and feedback current has been entered to phase comparator for phase comparison. By the voltage and current feedback phase comparator compare, when phase difference was zero with the current signal is the maximum value, the signal will sent into Labview for judging to pre-procedure frequency scanning module and dynamic frequency tracking module. Dynamic frequency tracking make the pre-procedure frequency scanning resonance frequency as reference. When the phase difference from 0° to 180° will activate the increasing the frequency scanning program.When the phase difference from 180° to 360°, will activate the decreasing the frequency scanning program until the processed stopped.Power amplifier and Labview generated by the frequency through the external voltage amplification, then enter the primary side circuit to achieve closed loop control. In wire power transmission experimental results has shown when the voltage provided at 166 V_rms (input power up to 10 W), which can produce the maximum amplitude of the tool front about 16 um with resonance frequencies 26030 Hz. Compared with the ideal designed of resonance frequencies 28000 Hz the error was 7.1%. In inductive power transfer experiment, the air gap was 0.2 mm, the processed pot-type core and wire diameter 0.5 mm with 50 turns are selected for inductive power transfer system. The result had shown that Inductive power transfer efficiency is only reached 27.9% (secondary side has received power about 7.51 W) and the tool amplitude reached about 15 um with the resonance frequency 26040 Hz. When added the compensation circuit and the resonant circuit the inductive power transfer efficiency improvement to 35% (secondary side received power up to 8 W) and reached about 16 um of the tool amplitude with the resonance frequency 26030 Hz; From the experimental results has shown, when the both coils are without difference, more turns will reduce the resonance frequency drift generated by the air gap ,this effect can reduce the resonance frequency drift. Our research was limited by the core circular groove dimensions, just only can place up to 50 turns, If the air gap have to increase in future as the bigger gap can be place more coil turn. With the bigger gap, will improve preventing the ability of resonant frequency change.Through from the experimental verification, to enhance the efficiency of power transmission methods was compensation circuit, more number of turns and the smaller diameter, all of these are the way to enhance transmission efficiency. Farther from the experiment verification and found tool and provided voltage amplitude has a linear relation, in the future we can design a controller for control the amplitude by control module, so as to achieve the optional of amplitudes tool. In this thesis the compensation circuit only for compensate a single frequency, in future will be Collocation with a frequency which generated by controller, thereby regulating the primary side of the corresponding impedance values, let the control system was more completed and more accurate.
47
Mei-YuHsieh e 謝媺育. "Motion Tracking of the Median Nerve in the Wrist by High-Frequency Ultrasonic Backscattering". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/06644026934625600881.
Testo completo
48
Shr, Jing-shaing, e 施景翔. "The Study of The Mechanical Resonance Tracking Circuit in Ultrasonic Vibration Assisted Cutting Tool System". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/29701388218592815650.
Testo completoAbstract (sommario):
碩士國立中正大學
機械工程所
94
Ultrasonic-vibration assistant (UVA) cutting has been verified to improve the machined quality of difficult-to-cut and brittle materials such as the ceramic, glass and compound materials. Researchers also found that the UVA cutting can be applied to the micro-structuring , thin-wall milling, and micro-hole drilling processes which are difficult to obtain a satisfied machined quality using the conventional machining processes. Many previous research works regarding the UVA cutting are focused the experimental verification of the performance demonstration of the UVA cutting. There are also some works conducted to the theoretical modeling and computer simulation of the UVA cutting mechanism. However, there is less effort on the study of the development of the electric circuits to automatically trace the resonance frequency of the UVA mechanical mechanism. This paper is focused on the development of the electric circuit and DSP unit for the automatically tracking the resonance frequency in UVA cutting. A theoretical force model regarding to the UVA cutting has been mathematically examined and discussed to explain the reason that the UVA cutting can reduce the cutting force effectively. We also discussed the mechanism and principle of the ultrasonic vibration generator based on the horn architecture. One of the important function in the UVA cutting is to make ensure the driving frequency from the electric power driving unit must be in coincident with the resonance frequency of the horn-based ultrasonic vibration generator. We therefore, designed an oscillatory circuit that is a voltage-controlled oscillator (VCO) using the quartz crystal to ensure its frequency stability and accuracy. A DSP unit with the VCO circuit is developed to automatically track the resonance frequency of ultrasonic-vibration generator when its resonance is changed. One reason of the resonance frequency change in the UVA cutting is the boundary condition of the ultrasonic-vibration generator changed when the cutting tool is in contact with the workpiece. A PZT vibration sensor was integrated into the horn structure to detect the vibration strain signal of the ultrasonic vibration generator. The sensed strain is then sent to the DSP unit for further signal processing. Our goal is automatically track the resonance frequency of the horn structure ultrasonic vibration generator in a frequency range between 10kHz and 25kHz. We have developed a frequency tracking algorithm that estimates the resonance frequency by scanning 7-9 stepped frequency in the desired band. The PZT strain sensor detects the vibration amplitude of each frequency. The vibration signal is then sent to the DSP unit for estimating the resonance frequency using a curve fitting method. It was verified that the estimation accuracy of the resonance frequency is closely matched to the value obtained from a commercialized spectrum analyzier.
49
Huang, Guo-He, e 黃國和. "Path tracking and obstacles avoidance using neural networks and ultrasonic sensors for car-like robots". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/84029016535283320624.
Testo completoAbstract (sommario):
碩士國立成功大學
電機工程學系碩博士班
94
This thesis focuses on the implementation of a car-like robot navigation hybrid control strategy characterized by global path tracking and obstacle avoidance based on neural network and ultrasonic sensors. The proposed car-like robot navigation control algorithm is capable of tracking a planned global path and avoiding the obstacle instantaneously. In order to enhance the adaptability and autonomy of the car-like robot, the algorithm adopts the concept of mode switching to provide a suitable control strategy in different situations. The control strategy consists of two modes: a tracking mode and an emergency mode. Most of the time, we set the robot in the tracking mode whose neural dynamic path-tracking algorithm enables the robot to follow a discretized planned path. In addition, we use ultrasonic sensors to detect whether there is any obstacle on the path during the navigation. Once these sensors detect the existence of the obstacles, the control strategy will switch to the emergency mode immediately. The emergency mode utilizes a neural classifier to judge the positions and possible shapes of the obstacles. Based on different positions and shapes of the objects determined by the classifier, we proceed to the obstacle avoidance control. The robot will go back to trace the global planned path after avoiding the obstacle. After software validation of the proposed algorithm, we use the ultrasonic sensors and a car-like robot developed by Parallax to verify the effectiveness and feasibility of the proposed control strategy.
50
Nieh, Shu-Kan, e 聶叔衎. "The feasibility assessment of the auto tuning respiratory compensation system with ultrasonic image tracking technique". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/2tn5h7.
Testo completoAbstract (sommario):
碩士國立臺北科技大學
機電整合研究所
102
The purpose of this study is to evaluate the feasibility assessment of the auto tuning respiratory compensation system with ultrasonic image tracking technique. According to the respiratory motion, the maximum range of organ displacement surrounding the lower lobe of lung is Superior-Inferior. The SI direction is issued with respiratory compensation in this study. However, there is respiratory signal delay in the system through generating ultrasound image, image processing, and signal transferring. For compensating the signal delay time, this study approaches the design of phase-lead compensator in the controller. There are two variants, variable “a” and gain of compensator, in the design of phase-lead compensator. When fixing the delay time for compensating, the variants will increase as the frequency of respiratory signal raise up. When fixing the frequency of respiratory signal, the variants will also increase as the delay time raise up. Before design of phase-lead compensator, we analyzed the system delay and concluded the respiratory delay time as 0.254+0.023 seconds in this study. For evaluating the feasibility assessment of the auto tuning respiratory compensation system with ultrasonic image tracking technique, there are 5 different frequencies of sine wave for simulating the respiratory signal as 0.5, 0.333, 0.25, 0.2, and 0.167 Hz. According to the varying frequency of sine wave, we tuned the variants of the compensator through the relationship of curve fitting. The conclusion is the rate of compensating the respiratory motion is stable and improved through phase-lead compensator. The rate of compensation promotes to 7.04-18.82% rather than without compensator, and the average of the compensation rate is approximately 97%. As a result, the auto tuning respiratory compensation system with ultrasonic image tracking technique is feasible. The advantages of the auto tuning respiratory compensation system as follows: 1. Non-invasive ultrasound sensor for active respiratory compensation. 2. Continuously radiotherapy treatment with this system. 3. Independent system suited for any treatment couch. 4. Operating easily for auto tuning respiratory compensation system.