Дисертації з теми "Wheelchair and seating systems"
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Kitchen, James Patrick. "Design of Wheelchair Seating Systems for Users with High-Tone Extensor Thrust." Thesis, Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/11500.
Повний текст джерелаSamuelsson, Kersti. "Active wheelchair use in daily life : considerations for mobility and seating /." Linköping : Örebro : Univ. ; Univ, 2002. http://www.bibl.liu.se/liupubl/disp/disp2002/med753s.pdf.
Повний текст джерелаPatrangenaru, Vlad Petru. "Development of dynamic seating system for high-tone extensor thrust." Thesis, Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-01112006-160352/.
Повний текст джерелаMoraes, Helton Scheer de. "Projeto conceitual de sistemas de assento para cadeira de rodas : uma abordagem sistemática." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/17629.
Повний текст джерелаThis work is an exploratory theoretical study on systematic design of special wheelchair seating systems, emphasizing its conceptual and functional aspects. According to the principles of assistive technology - which consists in the use of technologies applied to the caring of the needs of people with disabilities - the objectives of technical aids should be the promotion of optimal individual functionality. Thus, a literature review has been made on the theme of postural seating clinic, and the factors related to the health, the functionality, and the comfort or discomfort in the sitting position, allowing the identification of many explicit and implicit needs. By using the Systematic Design approach of Pahl & Beitz, complemented by some principles of Axiomatic Design and TRIZ, a functional requirements list has been made, consisting in the mapping between the customer needs in the customer domain and the functional requirements in the functional domain. In the next step, a functional structure has been created, showing the main functional elements and connections of the seating system, followed by the proposal of some working principles regarding the main identified sub-functions, including the analysis of analog technical systems of other technological fields. It was concluded that immobility is the main causative factor leading to the many functional and health problem associated with the sitting position, and therefore the main function of special seating systems must be to allow and actively promote frequent position changes. Moreover, it has become evident that information flows have a capital importance in proper functioning of seating systems, since they convey the homeostatic purpose of the movements being made, in order to continually redistribute and alleviate the local soft tissue deformations, and to promote the selective stabilization and motion of body segments that permit functional motor action.
Mâsse, Louise. "Kinematic and electromyographic analysis of wheelchair propulsion for various seating positions." Thesis, University of Ottawa (Canada), 1989. http://hdl.handle.net/10393/5986.
Повний текст джерелаOwen, Christopher. "Improved vehicle seating systems for managing rear impact events." Thesis, Cranfield University, 2005. http://dspace.lib.cranfield.ac.uk/handle/1826/11394.
Повний текст джерелаBush, Michael T. (Michael Thomas). "Enhanced comfort of seating systems through variable shape and compliance." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/41800.
Повний текст джерелаIncludes bibliographical references (leaves 73-74).
A new type of seat cushion has been developed. The present use of the cushion is in wheelchair seating, but it may ultimately have application to general seating, particularly in situations where comfort is a significant consideration. The cushion is intended to optimally distribute the interface pressure on the seat of a wheelchair user, as well as to provide an opportunity for active pressure management. The principal goal in developing this cushion is the prevention of pressure sores (decubitis ulcers). The theoretical and design considerations upon which the cushion was developed are presented. Experimental materials data, as well as results of a prototype system, are supplied. A prototype cushion has been produced, and additional work is ongoing. The cushion uses vacuum to manipulate the elastic/collapse properties of open-cell foam; effectively setting a maximum pressure at the human interface. Assuming appropriate auxiliary hardware, pumps, controllers, and sensors it would be appropriate to use this cushion as the basis of an actively controlled seating system.
by Michael T. Bush.
M.S.
Barks, Lee. "Wheelchair positioning and pulmonary function in children with cerebral palsy." [Tampa, Fla.] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0002107.
Повний текст джерелаMcDonald, Rachael Leigh. "Seating systems for children with cerebral palsy : study of acceptability and effectiveness." Thesis, University College London (University of London), 2004. http://discovery.ucl.ac.uk/1383524/.
Повний текст джерелаDupuis, Christine Angela. "A biomechanical comparison of two seating systems for moderately involved cerebral-palsied children /." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66156.
Повний текст джерелаMayi, Dieudonne. "An intelligent database for PSUBOT, an autonomous wheelchair." PDXScholar, 1992. https://pdxscholar.library.pdx.edu/open_access_etds/4332.
Повний текст джерелаGunaselvam, A. J. M. (Ariyamalar Jessica Miriam). "The use of seating systems to reduce whole body vibration exposure in the SA industry." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/50197.
Повний текст джерелаENGLISH ABSTRACT: The purpose of this study was to investigate the specification and use of appropriate seating systems to reduce whole-body vibration exposure in typical vehicles used in South African industry. As part of this study six suspension seats, which the manufacturers claim satisfy the requirements in ISO 7096 (2000), were tested. Six test subjects, three light and three heavy as specified in ISO 7096, were used to estimate the seat transmissibility functions in the vertical direction of the six different suspension seats. Transmissibility functions were measured in the laboratory using two excitation levels, 1m/s2 and 2 m/s2 r.m.s., of broadband frequency vibration and a spectrum approximating the EM5 spectral class in ISO 7096. SEA T values were calculated for operational vibration data measured in an articulated dump truck and a three-wheeled logger. It was shown that SEAT values for the EM1 spectral class could not be reliably estimated from seat transmissibility functions and need to be measured directly in the time-domain. The measurement procedures and seat selection criteria developed in this research project were used to compile a set of "Design Guidelines for Seat Selection for Whole-Body Vibration Control in Industrial Vehicles". These guidelines will provide manufacturers with an easy-to-implement methodology to control whole-body vibration transmitted to the operators of industrial vehicles and to comply with international regulations for whole-body vibration transmission.
AFRIKAANSE OPSOMMING: Die doel van die studie was om die spesifikasies en gebruike van geskikte sitplek stelsels van uit Suid Afrikaanse industriële voertuie, wat heel-liggaam vibrasies verminder, te ondersoek. Ses suspensiesitplekke, wat deur die vervaardigers voorgeskryf word, is getoets om te sien of hulle aan die ISO 7096 (2000) vereistes voldoen. Ses persone, waarvan drie lig en drie swaar is, soos in ISO 7096 voorgeskryf, is gebruik om die sitplek oordragsfunksies in die vertikale rigting vir die ses verskillende suspensiesitplekke te skat. Die oordragsfunksies is in die laboratorium gemeet deur twee opwekkingsvlakke, 1m/s2 en 2m/s2 w.g.k., van wyeband frekwensie vibrasie en n spektrum beraam tot die EMS spektrum soos in ISO 7096. 'SEA T' waardes was vanaf operationele vibrasie data wat in ge-artikuleerde vragmotors en driewiel- 'loggers' gemeet is bereken. Daar is gewys dat betroubare 'SEAT waardes vir die EM1 spektrum nie van sitplek oordragsfunksies geskat kan word nie, maar dat dit eerder direk van die tyd-gebied afgelees moet word. Die metings prosedures en die sitplek keuse vereistes wat in die navorsingsprojek ontwikkel is, is gebruik om "Ontwerp Riglyne vir Sitplek Keuse Vereistes vir Heel- Liggaam Vibrasie in Industriële Voertuie" saam te stel. Hierdie riglyne sal vervaardigers met maklik toepasbare metodes toerus om heel-liggaam vibrasie, wat oorgedra word na industriële voertuig operateurs, te beheer en om aan internasionale regulasies t.o.v. heel-liggaam vibrasie oordrag te kan voldoen.
Gu, Jun. "Dynamic impact testing and computer simulation of wheelchair tiedown and occupant restraint systems (WTORS)." Thesis, Middlesex University, 1999. http://eprints.mdx.ac.uk/8107/.
Повний текст джерелаAshley, Daniel. "Using Embedded Systems to Determine the Configuration of a Static Wheelchair Mounted Robotic Arm." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5344.
Повний текст джерелаMeruani, Azeem. "Tweel (TM) technology tires for wheelchairs and instrumentation for measuring everyday wheeled mobility." Thesis, Available online, Georgia Institute of Technology, 2007, 2007. http://etd.gatech.edu/theses/available/etd-04032007-174305/.
Повний текст джерелаGriškevičius, Julius. "Impulsinių apkrovų veikiamos netiesinės dinaminės sistemos "Neįgalus žmogus - vežimėlis - transporto priemonė" judesio stabilumo tyrimas." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20051108_133543-20717.
Повний текст джерелаChun-TingLi and 李俊廷. "Development and Biomechanical Evaluation of Wheelchair Seating System." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/96kj38.
Повний текст джерела國立成功大學
生物醫學工程學系
103
Elderly adults with lower limb disorders sitting on a wheelchair for an extended period of time may experience numerous complications. Critical complications in clinical practice include back pain, pressure ulcers, and decreased pulmonary function. Wheelchair seating system is a key factor that influences spinal angle, back muscle activation, interface pressure, pulmonary function, and subjective discomfort. Although numerous studies on wheelchair seating systems have been conducted, it seems that the aspect of aforementioned problems can still be further improved. For reduce the risks of back pain, pressure ulcers, and decreased pulmonary function in wheelchair sitting posture. This study proposed a novel wheelchair seating system concept: the backward thoracic with upward femur support seating system. The purpose of this study was to evaluate the spinal angle, back muscle activation, interface pressure, pulmonary function, and subjective discomfort when using the backward thoracic with upward femur support seating system in the elderly population. Twenty elderly people were recruited for this study. the backward thoracic with upward femur support sitting (TF) was compared with the relaxed slouching sitting (RS), flat back support sitting (FB), prominent lumbar support sitting (PL), and backward thoracic support sitting (BT). Spinal angle (thoracic, lumbar, and pelvic angles), back muscle activation (maximal voluntary isometric contraction of the thoracic erector spinae at T9, iliocostalis lumborum pars thoracis, lumbar erector spinae, and lumbar multifidus on both sides), interface pressure (total contact area, average pressure, and peak pressure on backrest and seat), pulmonary function (forced vital capacity, forced expiratory volume in 1 second, and peak expiratory flow), and subjective discomfort (neck, shoulder, upper-back, mid-back, lower-back, upper-arm, lower-arm, buttock, thigh, and leg) were measured and compared. The results of spinal angle measurement: the TF showed relatively higher thoracic kyphosis and lumbar lordosis when compared with the RS, FB and PL, no significant difference when compared with the BT; and it also showed a relatively neutral pelvic tilt when compared with the RS and LP, no significant difference was observed when compared with the FB and BT. The results of back muscle activation measurement: the TF showed relatively higher back muscle activity when compared with RS and lower back muscle activity when compared with the FB and PL in all tested muscles, no significant differences when compared with the BT. The results of interface pressure measurement: the TF showed relatively higher total contact area, average pressure and peak pressure on backrest when compared with the other sitting postures; and the BT showed relatively lower average pressure and peak pressure on seat when compared with the other sitting postures; nevertheless, the TF showed relatively lower total contact area, average pressure, and peak pressure on the back part of seat and higher total contact area, average pressure, and peak pressure on the front part of seat when compared with the BT. The results of pulmonary function test: the TF showed relatively higher pulmonary function values when compared with the RS, FB, and PL in all tested parameters, no significant differences were observed when compared with the BT. The results of subjective discomfort evaluation: the TF showed relatively lower subjective discomfort in upper-back, mid-back, and lower-back when compared with the RS, FB, and PL, no significant difference when compared with the BT; and it also showed relatively lower subjective discomfort in buttock and higher subjective discomfort in thigh when compared with other sitting postures. The backward thoracic with upward femur support seating system concept was suggested because it maintains an increased lumbar lordosis with rather neutral pelvic tilt, decreased back muscle activation, diminished pressure on the ischial tuberosities, improved pulmonary function, and lessened subjective discomfort in back and buttock which may help maintains a better wheelchair sitting posture for reduce the risks of back pain, pressure ulcers, and pulmonary function decline. The achievements of this study contribute to the decision-making processes of wheelchair seating systems for consumers, clinicians, and manufacturers.
Ni, Bi-Nian, and 倪百男. "Computer Aided Design and Development in Specialized Seating/Positioning Wheelchair." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/72448663046005658840.
Повний текст джерела國立成功大學
醫學工程研究所
87
Abstract Following with the melioration of medical and engineering technology, its to attach importance to welfare and living quality of deformity; The ultimately purpose of rehabilitated medicine is to improve the functional development of deformities. In Taiwan, the cerebral palsy have often developmental delay, deformity, and functional disabilities resulting from abnormal muscle tone, reflex and impaired sensory system. Early intervention for C.P. initiating from 2 to 3 years old, who have received early rehabilitation treatment, seating and body supports with assistant technology as well as long-term training and education, has demonstrated to provied promising outcomes in significantly improved abnormal muscle tone, reflex, bodys coordination and balanced control. Unfortunately, there is lack of assistive technology service program to provide systematical clinical evaluation and prescription of specialized seating / positioning support systems for the neuromuscular impairment in Taiwan. In addition, the fields of rehabilitation technology/assistive devices are very new with little R&D. This project is to design specialized seating/positioning wheelchair for the cerebral palsied. The goal is to provide clinical effective seating supports for minimizing abnormal muscle tone and reflex, and to improve balance control, movement coordination and functional activities for the cerebral palsied. This project select 93 cerebral palsied, measuring the anthropometric data of optimized seating position. Using Multivariate Cluster Analysis to divide subjects into two clusrters, according to ages 2~8 and 9~26. Then using Univariate Regression Analysis to predict the range of anthropometric data in which two clusters. In order to target the modular dimension of the wheelchair main structure, therefore to follow the example of case numbers, to select in each division and to decide the standard dimension of seating anthropometric, at the same time to transfer variance into wheelchair’s main structure and to proceed conceptual design. The project using AutoCAD to draw wheelchair dimension plane and three-D conceptual drawing. Using spacilized CAD/CAM software Pro/Engineer to simulate actual wheelchair specification and to compute the center of gravity position and inertia tensor of wheelchair structure. The results of this project indicate that the center of gravity position locate upon the center axis of cross bar, underscoring the seating system. Conforming to safety designing condition; the next, in all direction of inertial tensor respect to wheelchair are greater than tensors of plane. It means that the motion of wheelchair will be slower when it turning around. In the other hand, it will be more laborions when family members moving wheelchair. In view of obvious variabilitiy between each cerebral palsy. The design of individual seating and positioning wheelchair must to be base on biomechanics, posture controling, neuropathology, human factor engineering, to investigate objective clinical evaluation, to provide effective personal deficient device. Final destination of this research are (1) Keeping normal posture control and bring to maximum regular function. Promoting the patient independent ability. (2) Providing clinical training and collecting the data auxiliaryequipment(3) Training engineers to design and manufacture seating and positioning body support. (4) Shifting technology to medical treatment system. Developing science and technology about auxiliaryequipment.
Lin, Chien-hong, and 林建宏. "Modular Design of Specialized Seating / Positioning Wheelchair for the Cerebral Palsied." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/75478350673785229095.
Повний текст джерела國立成功大學
醫學工程研究所
89
In addition to medical and rehabilitative treatments, seating/positioning is important to the individual with central nervous deficits, particularly for moderate or severe cerebral palsied (CP) children. It has been reported statistically in Taiwan that 0.6 to 5.9 per 1,000 children are affected by CP. Proper seating and body support devices are useful in normalized muscle tone, decreasing the influence of pathological reflex and improving body stability and movement for preventing deformities, developmental delays and functional disabilities from their life span. This research purpose was to develop a modular design of specialized wheelchair (WC) and support systems for effectively customized fitting the individual’ seating/positioning needs, and for minimizing the product design and manufacturing cost. More specifically, this research was to: (1) develop and establish modular parameters of mechanical structure, mechanics and components for the design specification of specialized WC and body support system; (2) apply CAD/CAM and finite element method (FEM) for mechanical design, stress and strain analysis of structural and mechanic components, and manufacturing of modular products. The modular design of seating/positioning devices has been motivated from wide variations of age, body sizes, neuromuscular impairments and functional support needs for the CP population. The seat width and depth, backrest height and leg length, seat and back angles, and other components’ dimensions in linear and angular ranges need to be considered in the design of specialized WCs with foldable, anti-tip and braking functions. The design of body supports needs consider the size, shape and fitting location of head and trunk supports, H hardness and safety belts, abductor and tray. In Stage I, the main structural parameters of WC’ seat width and depth, backrest height and legrest length for modular design specifications were determined from Average Linkage and K-means methods of multivariable cluster analysis on the anthropometrics data measured and collected from 140 CP cases (ranging from 2 to 25 years old). The dimensional ranges of other components and body support systems were also statically determined from the subject’ database for modular design specifications. In Stage II, SolidWorks packages with constructive solid geometry of pipe, beam and shell components and triangular elements of FEM with strength analyses of maximum shear stress criterion were used for CAD design and stress-strain analysis of the structural and mechanic components and modular parts of the special wheelchair with A6061T6 aluminum alloy tubing and plate. In Stage III, CAM was used for the manufacturing and dies molding and assembly of the modular design products. The R&D has completed 3 prototype design modules of large, medium and small folding and reclining WCs equipped with anti-tip and brake devices for safety, the dimensional options include: 25.4, 31.8 and 41.4cm for WC width; 18, 21, 26, 31, 36, 41, 47, 51 and 56cm for both WC depth and backrest height; 15, 21, 27, 33, 39 and 44cm for legrest length; 5, 8 and 12 for seat angle; 75, 85 and 95mm in radius curve for head support; 40 and 65mm height for trunk support; and 60, 80 and 100mm width for abductor. All parts and components are easily inserted and removed adjustably to fit each individual needs. A seating/positioning protocol has been developed for clinical evaluation, measuring, prescription and fitting of the specialized WC and body supports. Fifty cases with severe cerebral palsy have been prescribed and fitted with their appropriate WCs and supports with the assembly of developed modular components according to their individuals’ needs. This pilot field testing of clinical application has demonstrated that the modular design of wheelchair and seating/positioning supports is useful to provide effective mobility aids, normalized muscle tone, body alignment and postural control , and to improved the influence of reflex, body coordination, balanced and movement, and functional abilities. The『Modular Design』seems to be highly applicable to satisfy widely varied seating/positioning needs for the CP, SCI, Strokes, TBI, MD and MS. In addition, the design and manufacturing process can be achieved with significantly minimized the product cost for wheelchair industries. Further clinical studies for application outcomes need to be investigated.
Lewis, Amy Rebecca. "Performance Benefits of Customised Seating Interfaces for Elite Wheelchair Racing Athletes." Thesis, 2018. http://hdl.handle.net/2440/120202.
Повний текст джерелаThesis (Ph.D.) -- University of Adelaide, School of Mechanical Engineering, 2019
Dhawan, Gunjan. "Addressing positioning and seating challenges in geriatric residents of a skilled nursing facility that use manual wheelchairs." Thesis, 2019. https://hdl.handle.net/2144/38180.
Повний текст джерелаChisholm, Jo-Anne Merinda. "Deinstitutionalization and community living services for persons with developmental disabilities : validation of a proposed model for providing wheelchair seating." Thesis, 1999. http://hdl.handle.net/2429/9299.
Повний текст джерелаNguyen, TN. "Advanced robust multivariable control strategies for powered wheelchair systems." Thesis, 2009. http://hdl.handle.net/10453/33838.
Повний текст джерелаNO FULL TEXT AVAILABLE. This thesis contains 3rd party copyright material. The hardcopy may be available for consultation at the UTS Library.
NO FULL TEXT AVAILABLE. This thesis contains 3rd party copyright material. ----- More often than not, impaired mobility results in fewer opportunities for socialising, and pursuing personal goals and pursuits. This can produce depression, anxiety and social isolation for physically impaired people. As an aid to mobility, an electric-powered wheelchair can assist a disabled person in improving their quality of life. The safe control of a conventional powered wheelchair nevertheless requires a significant level of skill, attention, judgment and appropriate user response. Like an automobile user, a wheelchair user may also encounter an accident and injury. To safely and comfortably accommodate a powered wheelchair user, there has been great advancement in recent decades in the development of autonomous and semiautonomous powered wheelchairs. However, the majority of this research focus on a supervisory control level related to developing navigation algorithms, shared-control approaches, and hand-free control strategies. Due to parameter uncertainties and external disturbances, an optimal performance and overall system robustness depends heavily on the low control level involved in precision motion control. Surprisingly, there is still very little research into control techniques for this level. Although many advanced control techniques have been developed for the low level control, none of these techniques are expected to be optimal. This is largely because they have not treated the powered wheelchair as a multivariable system. Due to interactions between different inputs and outputs, a control design task for a multivariable system can also be complicated. Some very effective solutions for the inherent issues pertaining to multivariable systems involve decoupling techniques. These endeavour to simplify a multivariable control problem through reduction to a series of scalar control problems. However, there is still a scarcity of research regarding robustness under effects of uncertainty and external disturbance. In this thesis, a combination of decoupling techniques and advanced control strategies leads to three new advanced multivariable control approaches. These approaches offer systematic solutions for problems of precision motion control in the low control level of a wheelchair system. New multivariable control approaches reduce a multivariable control problem into a series of scalar control problems, as such they have the advantage of involving less complexity and computation. Based on an identification framework, an approximate dynamic multivariable model is generated for a powered wheelchair to facilitate control implementation. The first multivariable control approach is derived from a combination of a Triangularization technique and a Model Predictive Control strategy. This approach can guarantee an optimal performance for a linear dynamic multivariable system. Apart from providing a systematic solution for a linear multivariable system, this approach also handles control problems naturally, takes into account of actuator limitations, and allows operation closer to constraints. Real-time implementation indicates the effectiveness of this approach for the powered wheelchair. The second multivariable control approach is derived from a combining a Triangularization technique and Optimal Neural Network Control strategy. This new approach guarantees the optimal performance for a dynamic multivariable system against parameter uncertainties. Experiment results related to path-following control of the powered wheelchair system reveal that, regardless of parameter uncertainty effects, this second multivariable control approach considerably improves system performance, robustness, and accuracy, in comparison with various popular control approaches. The results also demonstrate that coupling effects in the wheelchair dynamics are substantially reduced. The third multivariable control approach is derived from the combination of Diagonalization technique and Robust Neuro-Sliding Mode Control strategy. This novel approach can effectively cope in real time with parameter uncertainties and external disturbances to achieve robustness and a desired performance for a multivariable system. This third approach fully reduces the coupling effects on a multivariable system, eliminates the chattering phenomena, and avoids plant Jacobian calculation. Furthermore, it can also achieve fast and global convergence with less computation. The effectiveness of this novel approach has been verified through real-time implementation of the powered wheelchair system. The results guarantee robustness and desired performance of the overall system, even with the compounding effect of parameter uncertainties and external disturbances.
Yeh, Hung-Wen, and 葉弘文. "Development of Autonomous Powered Wheelchair Based on Fuzzy Navigation Systems." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/59057652310032414130.
Повний текст джерела長庚大學
醫療機電工程研究所
95
Autonomous robotic wheelchairs are widely discussed in recent years. Most of autonomous robotic wheelchairs were developed based on rich computation architecture to deal with complicated navigation efforts such as personal computers or embedded computers. However, such rich computation architectures increase cost of robotic wheelchair when compared to conventional powered wheelchairs. At the same time, large amounts of energy consumptions, lower reliability, and inefficient size of personal computers reduce the practicability of robotic wheelchair. In this paper, we present a low cost chip based solution to solve complicated wheelchair navigation problem based on distributed computing architecture. This solution is developed based on the programmable System-on-Chip (PSoC) computing and control architecture. The tasks within autonomous navigations are categorized into human machine interface, sensor collection, fuzzy logic based navigation functions, closed loop motion controller, and these tasks are individually implemented using the PSoC. Finally, the task oriented PSoC are integrated and fused to perform autonomous navigations of robotic wheelchairs. Consequently, the proposed PSoC based distributed computing architecture was successfully implemented and experimentally tested. The navigation results were verified using the results inferred from personal computer based computing architectures.
Ahmad, MYB. "Novel techniques for improved indoor positioning and localization using HF RFID." Thesis, 2013. http://hdl.handle.net/10453/23493.
Повний текст джерелаThis thesis investigates High Frequency Radio Frequency Identification (HF RFID) based positioning using a novel concept of multi-loop bridge reader antenna to localise moving objects such as autonomous wheelchairs in indoor environments. Typical HF RFIDs operate at 13.56 MHz and employ passive tags which are excited by the magnetic field radiated by the reader antenna. Positioning of moving objects using HF RFID systems derive location information by averaging the coordinates of detected passive floor tags by a portable reader antenna which are then recorded in the reader’s memory and database. To successfully detect floor tags, the reader’s antenna usually installed at the base of a moving object needs to be parallel to the floor. The magnetic field radiated by the HF RFID antenna is confined within its near field zone i.e., it is confined to a very close proximity of the antenna. This property of HF RFID helps to minimise interference to other appliances that may be present within the localisation area. Thus, HF RFID based positioning offers great potential benefit in providing location assistance in environments such as nursing homes, health care facilities, hospitals etc. However, despite the significant developments that have occurred in this field, there still exist problems with positioning accuracies obtainable mainly due to the uncertainty of the reader recognition area (RRA) of the reader antenna, which has not been fully addressed in literature. This thesis aims to address this problem by proposing the concept of multi-loop bridge reader antenna so that the reader recognition area is divided into multiple sub zones and an error signal (bridge signal) in terms of the position of the tag will be generated that helps to reduce the position uncertainty. The thesis starts with an investigation of the methods for creating multiple zones of RRA and the concept of bridge loop antenna from point of view of near magnetic fields. Different types of loop antennas for employing at the reader are electromagnetically analysed using both closed form solutions and numerical computations. The formation of reader recognition area (RRA) from different arrangements of loop reader antennas is also studied. To ensure that proposed bridge antennas can perform in realistic, non-ideal indoor environments where they are affected by proximity of metallic objects etc, we proposed methods of improvement. Equivalent circuits that reduce the computational complexity but can provide a broader understanding of the behaviour of bridge antennas have been formulated. This has lead to investigation of methods to minimise and/or eliminate the effect of metallic objects on the bridge signals. Next, we investigate the applicability of the proposed bridge loop antenna for the localisation and positioning of an autonomous wheel chair resulting in a realistic implementation of HF RFID based positioning system. The system is then tested to localise an autonomous wheelchair in an indoor environment using a grid of passive floor tags. Novel algorithms are proposed to estimate the position and orientation of the moving object using bridge signals generated by the bridge antenna coupled with the available dynamic information of the wheelchair. A comparison of our experimental results with the published results in the literature revealed significant improvements achieved by our proposed methods over existing techniques for estimating both, the orientation and position. Further, we demonstrate that the proposed technique obtains accurate position and estimation using much lesser number of floor tags (increased sparcity) than any of the currently published method, thus, contributing to simplified and easily expandable tag infrastructure deployment. We further extend the use of bridge loop antenna for situation when multiple tags are detected using the method of load modulation of the tags. When multiple tags present within the RRA of the bridge loop antenna, the resulting bridge signals incorporate information from all of the detected tags thus making it difficult to locate individual tags. To overcome this, we utilise states of the tag’s load modulation to separate these bridge signals, which then allow us to utilise them to estimate instantaneous position and orientation of the moving object. We performed analysis using equivalent circuits, as well as computational electromagnetic modelling of realistic antennas, which are then compared with experimental measurements carried on prototype systems. The comparison showed good agreement which validate our proposed method. Thus, the thesis incorporate contributions on various aspects of bridge loop reader antenna for HF RFID based positioning system. All full wave electromagnetic computations and simulations were carried by using a well known antenna design package “FEKO”. All the key analyses, equivalent circuits, antenna models and computational results for the proposed antennas and algorithms have been verified using extensive experimental campaigns to demonstrate the practical usefulness of the proposed methods. It is hoped that the findings in this thesis will result in newer efficient positioning systems in future.