Download or read book The Design and Control of Active Ankle foot Orthoses written by Kenneth A. Shorter and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Ankle foot orthoses (AFOs) can be used to ameliorate the impact of impairments to the lower limb neuromuscular motor system that affect gait. Existing AFO technologies include passive devices with fixed and articulated joints, semi-active devices that modulate damping at the joint and active devices that make use of a variety of technologies to produce power to move the foot. Emerging technologies provide a vision for fully powered, untethered AFOs. In this dissertation, a novel portable powered ankle-foot orthosis (PPAFO) cabable of providing un-tethered assistance during gait is presented. The PPAFO provides both plantarflexor and dorsiflexor torque assistance via a bi-directional pneumatic rotary actuator. The system uses a portable pneumatic power source (compressed CO2 bottle) and embedded electronics to control the motion of the foot. Experimental data from two impaired and five healthy subjects were collected to demonstrate design functionality. The impaired subjects had bilateral impairments to the lower legs that caused weakness to the plantarflexors, in one case, and to the dorsiflexors in the other. Data from the healthy walkers demonstrated the PPAFO0́9s capability to provide correctly timed plantarflexor and dorsiflexor assistance during gait. The results from the impaired subjects demonstrated the PPAFO0́9s ability to provide functional assistance during gait. Additionally, this dissertation presented a modeling and control approach to address limitations present in the PPAFO through the introduction of a new hardware configuration and new control architecture. A combined model consisting of both the PPAFO and the human foot and shank segments was first derived and validated. Next, the current and the new PPAFO system configurations were evaluated both in simulation and experimentally during three simplified functional gait tasks: (1) motion control of the foot at the start of the gait cycle, (2) plantarflexor torque assistance during late stance, and (3) dorsiflexor position control of the foot during swing. The resulting analysis showed that the new system configuration both outperformed and was more efficient than the current PPAFO configuration. The stringent design requirements of light weight, small size, high efficiency and low noise make the creation of daily wear assist devices challenging, but once such devices appear they will present new opportunities for clinical treatment of gait abnormalities.
Download or read book Design Feasibility of an Active Ankle foot Stabilizer written by Taresh D. Mistry and published by . This book was released on 2010 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt: Walking is the most common form of mobility in humans. For lower limb mobility impairments, a common treatment is to prescribe an ankle-foot orthosis (AFO) or brace, which is a passive device designed to resist undesired ankle-foot motion. Recent advances in actuator technology have led to the development of active AFOs (AAFOs). However, these devices are generally too bulky for everyday use and are limited to applications such as gait training for rehabilitation. The aim of this research was to investigate the feasibility of developing a novel Active Ankle-Foot Stabilizer (AAFS). The design criteria were mainly based on the strengths and limitations of existing AFOs. The sagittal plane functional requirements were determined using simulated gait data for elderly individuals and drop foot patients; however, it is intended that the device would be suitable for a wider range of disabilities including ankle sprains. A model of the foot was introduced to modify the moment of a deficient ankle where young healthy adult kinematics and kinetics were assumed. A moment deficit analysis was performed for different gait periods resulting in an AAFS model with two components: a linear rotational spring to modify the ankle joint rotational stiffness, and a torque source. The frontal plane functional requirements for the AAFS were modeled as a linear rotational spring which responded to particular gait events. A novel Variable Rotational Stiffness Actuator (VSRA) AFO was also investigated. It consisted of an actuated spring medial and lateral to the ankle to control sagittal plane ankle stiffness and a passive leafspring posterior to the ankle to control frontal plane ankle stiffness. Due to high forces and profile limitations, a spring and rotation actuator that satisfied the design criteria could not be developed, resulting in an infeasible design. Considering the high forces and moments required by the AAFS, a pneumatic approach was adopted. A novel Airbeam AFO, which consisted of a shank cuff and a foot plate to which airbeams were attached proximally and distally to the ankle, was examined. The joint rotational stiffness of the ankle would be controlled by the inflation of these individual cylindrical airbeams. To satisfy the functional requirements, the airbeam diameters and pressures were too large to meet the design criteria and were unrealistic for a portable device. Finally, a Pneumatic Sock AFO, which proved to best satisfy the functional requirements within the design criteria, was examined. The design consisted of an inner sock worn on the ankle, surrounded by anterior, posterior, medial, and lateral bladders which inflate against outer fabric shells. Although promising, the Pneumatic Sock AFO requires further investigation in regards to manufacturing and behaviour characterization before a functional prototype can be developed. Mechanical test methods to characterize the behaviour of the Pneumatic Sock AFO in the sagittal and frontal planes were developed including the control components required, the configuration of a test rig, and test procedures.
Download or read book Core Topics in Foot and Ankle Surgery written by Andrew Robinson and published by Cambridge University Press. This book was released on 2018-04-19 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: This concise guide offers an ideal overview of both the practical and theoretical aspects of foot and ankle surgery for trainees and junior consultants. Easy to read chapters cover all areas of surgery, from examination, imaging, and the biomechanics of the foot and ankle, to specific conditions including amputations and prostheses, deformities, arthritis, cavus and flat foot, sports injuries, Achilles tendon, benign and malignant tumors and heel pain. Fractures and dislocations of the ankle, hind-, mid- and forefoot are also covered, as are the foot in diabetes and pediatrics. Written by a team of international experts, the text is an accessible way to prepare for postgraduate examinations and manage patients successfully.
Download or read book Optimized Design and Testing of Kids Ankle Foot Orthosis A Case Study written by Harish Kumar Banga and published by GRIN Verlag. This book was released on 2019-11-20 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: Technical Report from the year 2019 in the subject Engineering - Mechanical Engineering, grade: 10.00, , language: English, abstract: Ankle foot orthosis (AFO) are externally applied device that a reused to support as well as control the foot and ankle joint of patients having foot deformity. Foot drop is caused by a deficiency in the ankle joint in which results in the weakness of ankle and toe dorsiflexion. This research proposes a new approach to design and performance evaluation of AFO fabrication that utilizes modeling, simulation and analysis software (like Open Sim, Ansys Work bench & Solid work) and additive manufacturing technologies to customize the fit form to an individual. By implementing a carbon fibre strut at ankle joint the design will result in a stronger, more comfortable, more flexible AFO that can adaptively constrain ankle movement for various different activities. GAIT Analysis was performed on six patients having foot drop, from the emotion analysis system in the GAIT lab. The data from the GAIT lab was then imported into the Open Sim to create a biomechanics simulation to extract the joint angle and joint moments. These value of ankle angle and moment with & without AFO was compared with normal value. The results show a considerable effect of the use of the AFO by drop foot patients in terms of ankle angle and ankle moments. Furthermore, the muscular analysis in terms of activation and forces also suggest that the dorsiflexors are assisted by the AFO during GAIT and the activation of the plantarflexion are considerably less during the lifting of the foot of the ground.
Download or read book Development of an Active Ankle foot Orthosis Model to Provide Support During Push off written by Sylvain Kpekou and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The human ankle joint plays a crucial role during walking. Due to disorders or injuries, thepotential of the ankle plantarflexors can be negatively altered and lead to a reduction ofmobility. In this situation an active ankle-foot orthosis (AAFO) can significantly enhancethe rehabilitation or the assistance of the affected patients. Currently, ABLE human motionis developing an exoskeleton for lower limb with 1 degree of freedom in the sagittal plane.The objective of this device is to allow people suffering from a low spinal cord injury to walkagain. The main issue of the current prototype is the absence of power source to provoke aforward progression of the leg during the push-off phase of the gait.In this paper, a new active ankle foot orthosis model is presented. To enhance the initi-ation of the swing, the ankle needs to provide a burst of power during the terminal stancephase. However, one of the main challenges in developing AAFOs is to find the balancebetween the design requirements of wearability and the high power requirements. Prior tothe actuator selection, a semi-systematic review is conducted to better understand the roleof the ankle joint during the gait and the most adequate actuator to use in our application.Subsequently, first model of AFO powered by a parallel elastic actuator (PEA) is developed.The design of the model aims to minimize the peak power requirements of the actuator.Since the weight of the motor is directly correlated with the power it generates, reducing thepower helps to keep the AFO under an acceptable weight. The potential benefits of the PEAare studied using 4 different models. Throughout the results analysis, non-backdrivability,unidirectional spring, peak power and energy consumption are evaluated.The integration of a unidirectional spring or a self-licking system did not improve theminimization of the peak power for this application. However the PEA actuator allows apeak power reduction of almost 60%using the parallel spring to provide the push of burstof power adequately. The work achieved in this thesis paves the way to further investigationsof the AAFO powered by a PEA and represents a first step to the integration of an AAFOin the current ABLE leg prototype.
Download or read book Design and Simulation of a Single hinge and Adaptive Ankle Foot Orthoses Based on Superelasticity of Shape Memory Alloys written by Morteza Gorzinmataee and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this thesis is to propose and develop new designs of Ankle Foot Orthosis (AFO) based on superelastic characteristics of shape memory alloys (SMAs). The problem investigated in this research is a human gait abnormality called drop foot caused by the paralysis of the muscles which allow the ankle to dorsiflex. This neuromuscular disorder results in foot slap after heel strike and toe drag during leg swing. As the most common solution, drop foot patients use an orthotic device called AFO add support and improve their gait. However, development of a more compact assistive device, which could passively or actively secure the normal gait requirements, is still a need by both patients and clinicians. Based on investigations and experimentations performed in Dynamic and Smart Systems Laboratory at University of Toledo, SMA is a potential solution due to its unique stiffness behavior and hysteretic characteristics. In this work superelastic characteristics of SMAs is considered as an enabler in the development of new generation of AFOs. Within this work a passive AFO design is proposed which employs a superelastic SMA element as the hinge of the device. This SMA hinge controls the ankle motion by storing and releasing energy during walking. The superelastic element enables the AFO to provide sufficient torque during dorsiflexion to raise the foot in the swing phase of the gait. In order to evaluate the design performance a comprehensive gait analysis study is performed to extract the requirements of motion, understand the critical loads, and calibrate the desired stiffness profiles for the ankle and the superelastic element. A Finite Element Analysis is performed to realize an optimum design for the SMA hinge. Preliminary simulations are carried out in the sagittal plane of the body to verify the functionality of the design in providing the motion requirements. Unlike existing AFOs with two hinges, the proposed design uses only one hinge. The multi-axial loading of the ground reaction in 3D is then simulated to estimate lateral response of the hinge in preventing hypermobility and securing the walking stability. To maintain stability the hinge should limit the motion in directions other than rotation in the sagittal plane. In addition to this passive hinge, superelastic SMA is also envisioned to realize an active AFO. To this end, an active superelastic SMA element which is adjusted structurally and dynamically is used to reproduce the stiffness variation of a healthy ankle. This concept could produce a controlled stiffness profile desired for different walking conditions such as various speeds. Actuation mechanism design for this concept is also discussed. Although, the major contribution of this study is developing a reliable passive AFO design, experimental and numerical analyses confirm the functionality of both passive and active SMA AFOs.
Download or read book Active Ankle Foot Orthotic written by Jose Gutierrez and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Force controllable Ankle Foot Orthosis AFO to Assist Drop Foot Gait written by Joaquin Andres Blaya and published by . This book was released on 2002 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Atlas of Orthoses and Assistive Devices written by Joseph Webster and published by Elsevier Health Sciences. This book was released on 2017-11-24 with total page 585 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in the material sciences, 3D printing technology, functional electrical stimulation, smart devices and apps, FES technology, sensors and microprocessor technologies, and more have lately transformed the field of orthotics, making the prescription of these devices more complex than ever before. Atlas of Orthoses and Assistive Devices, 5th Edition, brings you completely up to date with these changes, helping physiatrists, orthopaedic surgeons, prosthetists, orthotists, and other rehabilitative specialists work together to select the appropriate orthotic device for optimal results in every patient.
Download or read book Management of Chronic Musculoskeletal Conditions in the Foot and Lower Leg E Book written by Keith Rome and published by Elsevier Health Sciences. This book was released on 2014-09-18 with total page 271 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridging the gap between undergraduate and postgraduate knowledge and experience, this new full colour resource uses an interdisciplinary approach to help manage chronic conditions – osteoarthritis, Achilles tendinopathy, gout, rheumatic diseases, forefoot/rearfoot entities, stress fractures/reactions, cerebral palsy – in the lower limb and foot. Each chapter includes sections on predisposing factors, diagnosis, impairments, function, quality of life and management strategies while highlighting any complex features of a condition which may present. The latest advances are discussed with suggestions for new paths of research – ‘future directions’. The text is further supported by additional commentaries from internationally renowned researchers who highlight the key elements of the work and provide a supplementary perspective of the particular clinical condition. A general view of the patient’s needs is offered throughout, connecting clinical realities to real-world patient experiences. Management of Chronic Conditions in the Foot and Lower Leg is a comprehensive, practical tool that can be used to inform daily decision making in practice as well as to support those who build policy and management strategies in the clinical areas covered. Clear content and structure supported by full colour illustrations Includes less discussed conditions such as gout and cerebral palsy Focus on pain, impairment, function, quality of life and management strategies Critical reflections by experts highlight current clinical practice and thinking in research Provides a sound interpretation of research findings Features patient-reported outcome measures and health related behaviour strategies
Download or read book Developing an Active Ankle Foot Orthosis Based on Shape Memory Alloys written by Ehsan Tarkesh Esfahani and published by . This book was released on 2007 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is aimed toward the development and evaluation of a novel active ankle foot orthosis (AAFO) based on shape memory alloy (SMA) actuators. This device intends to fill the gap in the existing research aimed at helping patients with drop foot muscle deficiencies as well as rehabilitation activities. To examine the feasibility of this idea, the current study focuses on the dynamic behavior of the ankle joint. A SMA manipulator with a similar dynamic behavior is experimentally evaluated. Nonlinear behavior of SMA wires requires nonlinear control techniques such as Sliding Mode Controller (SMC) for tracking the desired ankle angle. Simulation results of several different techniques are compared (PID, SMC, SMC-PID and Adaptive PID) and finally the experimental result of an Adaptive PID is used to check the stability of walking. This results shows that an Adaptive PID controller as a robust and precision control can be used to track the desired position of the ankle. However for frequencies more than 0.25 Hz (time cycle less than 4 seconds), the walking conditions will be unstable due to slow cooling process.
Download or read book Insertion Point Eccentricity Controlled Ankle Mechanism in Conjunction with Functional Electric Stimulation written by Arkady A. Polinkovsky and published by . This book was released on 2010 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this project was to have a prototype of an active Ankle Foot Orthosis (AFO) that would help control and assist plantar flexion and orsiflexion with a single motor acting as an antagonistic pair of uscles. To control the amount and direction of the torque about the ankle Insertion Point Eccentricity Control (IPEC), a way of moving a stored energy, was used. The device, a heavily altered Ankle Foot Orthosis (AFO), would help control and assist plantar flexion and dorsi-flexion. A challenge was also to keep the weight added to the standard AFO at no more than one pound. After initial testing, it was seen that the IPEC AFO is able to provide 3.51 ± .05 Nm about the ankle in dorsi-flexion and 3.88 ± .15 Nm in plantar flexion with a spring modulus of 17.76 lbs/inch and an initial tension of 17.24 lbs. The torque was found to be sufficient to move the foot during walking. The design0́9s most important objective was to be advantageous and safe for the user. The user would range from a Spinal Cord Injury (SCI) subject to a stroke subject with drop-foot or other disorder concerning the ankle. The IPEC AFO cycles quickly enough for an SCI FES user. The IPEC AFO is an improvement because it leverages energy stored in the spring to reduce power required by the motor.
Download or read book Towards a Shape Memory Alloy Based Variable Stiffness Ankle Foot Orthosis written by Minal Bhadane-Deshpande and published by . This book was released on 2012 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: Drop foot is a neuromuscular disorder causing a loss of use of the muscles that lift the foot. Drop foot can primarily be caused by stroke, cerebral palsy, multiple sclerosis, or neurological trauma. The two major complications of drop foot are slapping of the foot after heel strike (foot slap) and dragging of the toe during swing (toe drag). The current treatment options like Ankle Foot Orthosis (AFO) and Functional Electrical Stimulation, while offering some biomechanical benefits, do not adapt to different walking conditions and fail to eliminate significant gait complications. This study proposes a novel Active Ankle Foot Orthosis design which combines an AFO and combinations of shape memory alloy (SMA) wires. The key feature of SMA is its ability to undergo seemingly large plastic strains and subsequently recover these strains when a load is removed or the material is heated. Because of this distinct thermomechanical behavior, SMA can potentially resolve some of the gait complications associated with use of an AFO. To provide a basis for the design of an AAFO, gait analysis is performed on healthy subjects along with drop foot patients to establish the deficiency in ankle stiffness characteristics. The initial verification of the thermomechanical behavior of SMA in the form of stiffness variation is carried out by testing SMA wire combinations. Based on these experiments a COMSOL model is verified which is used for simulating the combinations of SMA wires. Through simulations and experiments it has been shown that changing the combination of SMA wires result in variable stiffness pattern. The performance of different types and combinations of SMA wires are tested successfully on an AFO. The preliminary results demonstrate that SMA wires provide controlled plantarflexion during stance phase, and active dorsiflexion in the swing phase by using stiffness variations of shape memory alloy wires. In particular, the AAFO helps to avoid major complications of drop foot gait. Thus, with the development of a control strategy, and using the inherent stiffness variation of SMA wires it is possible to produce close-to-normal stiffness profiles in the ankle motion of drop-foot patients who are wearing the AAFO.
Download or read book Athletic Footwear and Orthoses in Sports Medicine written by Matthew B. Werd and published by Springer Science & Business Media. This book was released on 2010-06-17 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: This concise manual is for sports medicine specialists who want to effectively prescribe footwear and orthotics for the athlete. The book provides a logical approach designed to maximize performance and minimize injury. In addition to the fundamentals, including athletic foot types, basic biomechanics, and gait evaluation, the text also addresses the assessment and prescription of shoes, inserts, and orthotics. The work covers new technologies and sports-specific recommendations as well. By presenting essential information in a convenient and easily accessible format, this book will prove to be invaluable for sports medicine physicians, podiatrists, physical therapists, athletic trainers, and other specialists when making footwear recommendations for athletes.
Download or read book Postgraduate Orthopaedics written by Paul A. Banaszkiewicz and published by Cambridge University Press. This book was released on 2012-08-16 with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt: The must-have book for candidates preparing for the oral component of the FRCS (Tr and Orth).
Download or read book Footwear and Foot Orthoses written by Anita Ellen Williams and published by Churchill Livingstone. This book was released on 2010 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: Footwear and Foot Orthoses provides students and clinicians with a guide to the information they require to underpin their clinical decision making. Pocket Podiatry provides all the essential information for a modern Podiatric practice. Examination and diagnosis, aetiology, prognosis and management are provided in a practical and informative manner. With its clarity and portability, students will find the Pocket Podiatry series an invaluable companion to their studies, whilst practitioners will appreciate its clinical orientation and concise format. Relevant - focuses on key information Convenient - handy sized volumes can easily be carried in coat pocket Practical - Core theory and a maximum of clinical emphasis Accessible - user-friendly format with summaries and helpful tips Specialist - written specifically for Podiatrists by true experts Clear - full colour design throughout A new series of pocketbooks specifically written for podiatry students and practitioners that answers all your questions on the main areas of study and practice, in handy, affordable, full colour volumes specially designed for quick reference and ease of access.
Download or read book Machines Mechanism and Robotics written by Rajeev Kumar and published by Springer Nature. This book was released on 2021-07-21 with total page 1830 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume includes select papers presented during the 4th International and 19th National Conference on Machines and Mechanism (iNaCoMM 2019), held in Indian Institute of Technology, Mandi. It presents research on various aspects of design and analysis of machines and mechanisms by academic and industry researchers.
