Download or read book Design and Development of Bionic 3D Printed Upper limb Exoskeleton for Stroke Rehabilitation written by Yousef Alshahrani and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Those who have had a stroke need long-term physical rehabilitation treatments. The conventional manual hands-on method is time-consuming and cannot offer low-cost, long-term rehabilitation services. Furthermore, the hands-on method is subjective and is dependent on the competence level of physiotherapists. To address these problems, more research and effort are being directed into the development of robotic-assisted rehabilitation technologies. For decades, upper-limb exoskeleton devices have been researched and developed for upper-limb rehabilitation. Some products have been tested on post-stroke patients. However, there are many limits and problems in this field. It currently needs a bionic mechanical design for the upper-limb exoskeleton, focusing mainly on human-machine joint misalignment. Furthermore, upper-limb exoskeleton volitional control is still far from acceptable.In this study, previous attempts to develop an upper-limb exoskeleton were discussed. Important challenges related to mechanical exoskeleton design and control strategy development were undertaken. A new robot control mechanism, known as the mirror or synchronous motion-control method, was developed, as well as tactics for promoting robotic systems in clinical usage. Six healthy individuals participated in an experiment to verify the performance of the motion-controlled upper-limb (UL) exoskeleton. In a 2D panel, the UL exoskeleton executed sketching movements based on the UL movements of a healthy participant. To evaluate the accuracy of the drawing performance, the drawings produced by the UL exoskeleton were compared to drawings done by the participant. To evaluate the inter-rater agreement between the drawings, and thus evaluate UL exoskeleton performance, a reliability statistical study (Cronbach test) was conducted and an image comparison using Python was performed to see the accuracy.

Download or read book Designing Exoskeletons written by Luis Adrian Zuñiga-Aviles and published by CRC Press. This book was released on 2024-03-27 with total page 355 pages. Available in PDF, EPUB and Kindle. Book excerpt: Designing Exoskeletons focuses on developing exoskeletons, following the lifecycle of an exoskeleton from design to manufacture. It demonstrates how modern technologies can be used at every stage of the process, such as design methodologies, CAD/CAE/CAM software, rapid prototyping, test benches, materials, heat and surface treatments, and manufacturing processes. Several case studies are presented to provide detailed considerations on developing specific topics. Exoskeletons are designed to provide work-power, rehabilitation, and assistive training to sports and military applications. Beginning with a review of the history of exoskeletons from ancient to modern times, the book builds on this by mapping out recent innovations and state-of-the-art technologies that utilize advanced exoskeleton design. Presenting a comprehensive guide to computer design tools used by bioengineers, the book demonstrates the capabilities of modern software at all stages of the process, looking at computer-aided design, manufacturing, and engineering. It also details the materials used to create exoskeletons, notably steels, engineering polymers, composites, and emerging materials. Manufacturing processes, both conventional and unconventional are discussed—for example, casting, powder metallurgy, additive manufacturing, and heat and surface treatments. This book is essential reading for those in the field of exoskeletons, such as designers, workers in research and development, engineering and design students, and those interested in robotics applied to medical devices.

Download or read book Grasp written by Xavier Cano Ferrer and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: There are 3 millions of upper limb amputees worldwide, and this represents a minority of 5% of the total number of amputees. For this reason, the costs of production of an advanced bionic limb are so elevated. This impacts on the acquisition prices, setting them between 25.000 and 75.000 €. The main motivation of the present work has been to create a design of a bionic hand with 6 degrees of freedom (DOF), which can be 3D printed with competitive features respect to the best commercial models available in the market in terms of flexion-extension speed and force. Each of the aims of the project has been a different technological challenge. The main objectives can be summarised as follows: (1) the bionic hand must be able to reproduce the 6 most important types of grips required in order to carry out activities of daily life; (2) all the components: electronics and actuators should be included into the palm of the hand to reduce the possible space occupied in the forearm; (3) the hand mass should be less than 400g, which the weight critical for the user to be considered too heavy; (4) the bionic hand should be easily assembled and programmed by the same user once you have downloaded the open source files; (5) the total cost of the hand must be below 500 € including all components. Finally, the greatest challenge is to achieve all these objectives and at the same time be competitive with respect to existing commercial projects. The project includes the development of various designs and 3D printable prototypes that have been carried out during the previous 4 years. All the experience and knowledge acquired with these prior designs culminated in Grasp: the latest design, presented in this work. Grasp sets out to achieve all the objectives that have emerged from the needs that must be covered to provide a product with the optimal quality and functionality.

Download or read book Augmenting Human Manipulation Abilities with Supernumerary Robotic Limbs written by Irfan Hussain and published by Springer Nature. This book was released on 2020-07-17 with total page 155 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers a timely report on an emerging topic in the field of wearable assistive technology: the design and development of robotic extra fingers. After a concise review of the state of the art and a description of earlier prototypes, it discusses the authors’ efforts to address issues such as portability and wearability of the devices, including strategies to reduce fatigue and to integrate the motion of the extra fingers with that of the human hand. The book also explores optimized control algorithms and the design of wearable sensorimotor interfaces, and presents a set of tests carried out on healthy subjects and chronic stroke patients. Merging concepts from robotics, biomechanics, human factors and control theory and offering an overview of supernumerary robotic fingers, including the challenges, this book will inspire researchers involved in the development of wearable robotic devices and interfaces based on the principles of wearability, safety, ergonomics and user comfort.

Download or read book Control and Dynamic Manipulability of a Dual Arm Hand Robotic Exoskeleton System EXO UL8 for Rehabilitation Training in Virtual Reality written by Yang Shen and published by . This book was released on 2019 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Every year there are about 800,000 new stroke patients in the US, and many of them suffer from upper limb neuromuscular disabilities including but not limited to: weakness, spasticity and abnormal synergy. Patients usually have the potential to rehabilitate (to some extent) based on neuroplasticity, and physical therapy intervention helps accelerate the recovery. However, many patients could not afford the expensive physical therapy after the onset of stroke, and miss the opportunity to get recovered. Robot-assisted rehabilitation thus might be the solution, with the following unparalleled advantages: (1) 24/7 capability of human arm gravity compensation; (2) multi-joint movement coordination/correction, which could not be easily done by human physical therapists; (3) dual-arm training, either coupled in joint space or task space; (4) quantitative platform for giving instructions, providing assistance, exerting resistance, and collecting real-time data in kinematics, dynamics and biomechanics; (5) potential training protocol personalization; etc. However, in the rehabilitation robotics field, there are still many open problems. I am especially interested in: (1) compliant control, in high-dimensional multi-joint coordination condition; (2) assist-as-needed (AAN) control, in quantitative model-based approach and model-free approach; (3) dual-arm training, in both symmetric and asymmetric modes; (4) system integration, e.g., virtual reality (VR) serious games and graphical user interfaces (GUIs) design and development. Our dual-arm/hand robotic exoskeleton system, EXO-UL8, is in its 4th generation, with seven (7) arm degrees-of-freedom (DOFs) and one (1) DOF hand gripper enabling hand opening and closing on each side. While developing features on this research platform, I contributed to the robotics research field in the following aspects: (1) I designed and developed a series of eighteen (18) serious VR games and GUIs that could be used for interactive post-stroke rehabilitation training. The VR environment, together with the exoskeleton robot, provides patients and physical therapists a quantitative rehabilitation training platform with capability in real-time human performance data collection and analysis. (2) To provide better compliant control, my colleagues and I proposed and implemented two new admittance controllers, based on the work done by previous research group alumni. Both the hyper parameter-based and Kalman Filter-based admittance controllers have satisfactory heuristic performance, and the latter is more promising in future adaptation. Unlike many other upper-limb exoskeletons, our current system utilizes force and torque (F/T) sensors and position encoders only, no surface electromyography (sEMG) signals are used. It brings convenience to practical use, as well as technical challenges. (3) To provide better AAN control, which is still not well understood in the academia, I worked out a redundant version of modified dynamic manipulability ellipsoid (DME) model to propose an Arm Postural Stability Index (APSI) to quantify the difficulty heterogeneity of the 3D Cartesian workspace. The theoretical framework could be used to teach the exoskeleton where and when to provide assistance, and to guide the virtual reality where to add new minimal challenges to stroke patients. To the best of my knowledge, it is also for the first time that human arm redundancy resolution was investigated when arm gravity is considered. (4) For the first time, my colleagues and I have done a pilot study on asymmetric dual-arm training using the exoskeleton system on one (1) post-stroke patient. The exoskeleton on the healthy side could trigger assistance for that on the affected side, and validates that the current mechanism/control is eligible for asymmetric dual-arm training. (5) Other works of mine include: activities of daily living (ADLs) data visualization for VR game difficulty design; human arm synergy modeling; dual-arm manipulation taxonomy classification (on-going work).

Download or read book Dual Reconfigurable Exoskeleton Hand System with Opposable Thumbs written by Peter Walker Ferguson and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Between a global pandemic, aging population, and labor shortages, there is an ongoing spike in the demand for healthcare that cannot be satisfied with traditional methods and the human workforce. Robotic technology offers a solution to this dilemma; applying robotics to healthcare is an active area of research that has begun to be widely commercialized. Whilethere are many potential avenues for robots to improve health and well-being, my research has focused on two areas in particular: the development of robotic hand exoskeletons for rehabilitation and the enhancement of robotic surgery via automation and sensor development. Exoskeletons have been shown to be effective for use in physical rehabilitation of numerous conditions including spinal cord injury and stroke. However, at present, the huge majority of exoskeleton systems are constructed for only the arm (from shoulder to wrist), back, lower limbs, or hands. Few systems have been developed that combine both full arm and hand systems, and those that do generally have limited actuation of the hand. This is partly because the mechanical complexity of the hand requires rigid hand exoskeletons to be complex and bulky if they are able to control many of the important degrees of freedom. This bulk and complexity makes the hand systems challenging to successfully integrate onto the distal end of an arm exoskeleton. However, there is significant demand for combined arm and hand rehabilitation exoskeletons because many activities of daily living, that physical therapy focuses on retraining, require reaching and grasping together. The overarching goals of this research are to develop a novel hand exoskeleton, experimentally evaluate its capabilities in preparation for application to stroke rehabilitation, and integrate it on the existing EXO-UL8 and concurrently developed BLUE SABINO upper limb exoskeleton systems. Chapter 1 provides an introduction on hand exoskeleton systems, with a focus on those designed for rehabilitation. My work on hand exoskeletons started by inheriting a hand exoskeleton mechanical design from Brando Dimapasoc, a graduating Master's Degree student, that was developed as part of NSF Award #1532239. The system was intended to be attached to the EXO-UL8 and BLUE SABINO arm exoskeletons, had six active and six passive degrees of freedom, had three reconfigurable linkages to control the thumb and two groupings of fingers, used a bowden cable transmission system to enable remote placement of actuators, and was optimized to fit 90% of the general population. However, the design had only been tested as a 3D-printed prototype in a modified and simplified form. Further, the necessary electronic hardware (other than motor and sensor selection) and control software had not been started. Thus, the first stage of my research was to bring this first-generation hand exoskeleton to a functional state. This involved the mechanical assembly, the electrical design and assembly, and the software and control development of the system. Through testing, it was determined that a significant number of improvements must be made to the system in order for it to be suitable for use. Details of this work are contained in Chapter 2. With the lessons learned from development and testing of the first-generation hand exoskeleton, the next stage of my research involved the nearly complete redesign of the system in order to create the second-generation hand exoskeleton named the "Opposable-Thumb Hand Exoskeleton for Rehabilitation" or "OTHER Hand". As the name implies, the system is designed to control opposition/reposition of the thumb in addition to the flexion/extension of each digit. This is a notable feature, not only because of the importance of opposition/reposition in many grasping tasks, but also because only a handful of exoskeletons in the literature control this motion. The OTHER Hand shares a number of features with the first generation system, though the execution of each is different. It attaches to both the EXO-UL8 and BLUE SABINO arm exoskeletons, is actuated using a Bowden Cable transmission such that the motor pack can be located remotely, has three reconfigurable linkages to control the thumb and two groupings of fingers in order to enable nearly all grasps, and is optimized to fit 90% of the population. The system has six active and eight passive degrees of freedom per hand. Chapter 3 documents the design of the OTHER Hand. Due to the numerous novel design choices made for the OTHER Hand, combined with the mechanical complexity of the hand in general, and thumb in particular, it is not feasible to know with certainty the types of grasps that can be actuated in the exoskeleton for the wide range of hand shapes and sizes. As such, it is necessary to validate the design of the OTHER Hand through testing with a group of subjects. This was accomplished through adaptation of the Anthropomorphic Hand Assessment Protocol for use with an exoskeleton to test the ability of thirteen subjects to grasp and manipulate 25 objects of the Yale-Carnegie Mellon-Berkeley Object Set using eight prehensile grasps and two non-prehensile hand postures. Additionally, the OTHER Hand was mounted on the EXO-UL8, and both systems were manually controlled to verify compatibility, workspace, and ability to bi-manually grasp a sample object. Chapter 4 presents the testing protocol and results. While exoskeletons for rehabilitation is an increasingly popular research area, robotic surgical platforms already have widespread commercial use and profound effects on clinical outcomes. Classically, these systems are controlled directly by a surgeon at a console in the same or adjacent room. They can augment the senses and movement precision of the surgeon during open or laparoscopic surgery in order to enhance the surgeon's skills. However, surgeons commonly work exceptionally long hours in an environment where a single mistake can be fatal. Additionally, certain surgical subtasks are time-consuming, repetitive, and common to many different operations. Automating these subtasks has the potential to reduce the burden on surgeons while standardizing outcomes. Automation of one such subtask, soft tissue manipulation, is described in Chapter 5. Cataract surgery ranks among the most common operating room procedures worldwide. The aim of the surgery is to replace the clouded biological lens with a clear synthetic lens. Despite the prevalence, this operation is currently performed manually by a surgeon, and generally is fast, standardized, and safe. However, the human body is notably non-optimal for performing cataract surgery due to the transparency and fragility of the tissues of the eye. In order to remove the lens, it is standard to break it apart with phacoemulsification, use an irrigation/aspiration handpiece to aspirate the lens material, and then polish any remaining lens material from the capsular bag. Unfortunately, the back of this bag, the posterior capsule, is transparent, mere microns thin, and easily ruptured from contact, ultrasound energy, or pressure. Rupturing the posterior capsule causes the vitreous of the inner eye to spill out, resulting in critical failure of the surgery. Additional information about the location of the tool tip within the eye could be used to reduce the risk of such a failure. To this end, a proof-of-concept modification of a tool to add bioelectrical impedance sensing and tissue classification was developed and tested on porcine eyes. This research is summarized in Chapter 6

Download or read book IGrab Hand Orthosis written by Lokesh Kumar Saharan and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Four million Americans are suffering from upper limb malformation due to various neurological disorders. Efforts have been made to develop orthosis and prosthesis to improve the quality of life of those individuals. This work primarily focuses on the design, development and analysis of a hand exoskeleton created using novel actuators called twisted and coiled polymer (TCP) muscles, 3D printed structures, and a garment glove for a rehabilitation of the patients with partial or no motor abilities in the hand. The 3D printed exoskeleton incorporates the TCP muscles (380 mm long and 1.25 mm in diameter) wrapped around pulleys to pull the tendons which in turn facilitate the flexion motion of fingers. Extension motion was done using elastic cords on the dorsal side of the hand. A custom made biomimetic hand was developed using a 3D printed hand skeleton and casting Ecoflex 30 silicone to mimic similar stiffness as the natural hand and to test the orthosis device. Eight different orthotic hands were designed and developed, and we showed precise prehensile and non-prehensile hand movements. Further, we analyzed the motions of the robotic and the orthotic devices using Euler-Lagrangian equations. The modeling included the derivation of equation of motion for the three-link under-actuated serial manipulator suitable for numerical simulations. System identification was used to determine the electro-thermo-mechanical model transfer functions of the TCP muscle. These two transfer functions were integrated with the Euler-Lagrange model in the Simulink®. Then, a measured power and force profile of the TCP muscle was used as input to the Simulink model to determine the motion behavior of all three joints of the robotic finger. Errors in the torque and force profile were determined statistically. Also, sensitivity analysis was conducted using key model parameters. The TCP muscles are the most recent revolutionary development in the field of the smart actuators, with high power to weight ratio 5.4 kW/kg, 16 %- 200 % actuation stroke and stress of 1- 35 MPa presented by Carter Haines in 2014 introductory science paper and in a subsequent study in 2016. In addition, the precursor material for the muscles is inexpensive (~$5/kg) compared to a shape memory alloy ($3000/kg) and the muscle fabrication is easier. Also, the hysteresis is minimal for the TCP muscles but the efficiency is one of the limitations of the actuator which is close to 1%. We have developed an experimental setup to fabricate and characterize the TCP muscles under different loading conditions and determine stress, strain, and power, number of cycle and temperature rise. We used silver coated nylon 6,6 multifilament threads and performed actuation tests, microscopy and tensile tests . Different geometries of the TCPs 1-ply, 2-ply and 3-ply muscles were studied for the effect of speed of the rotation during fabrication and natural frequency. Further, the low efficiency of the muscles is addressed with the design and implementation of two different types of the locking mechanism in the prosthetic and orthotic devices. The locking mechanisms have shown significant improvements in the efficiency of the muscle. The novelty of this work lies in the design, development and modeling of the orthotics device, improving the muscle efficiency along with study and characterization of the TCP muscles.

Download or read book Exoskeleton Robot for Upper Limb Rehabilitation written by Ho Shing Lo and published by . This book was released on 2014 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: Current physical rehabilitation services for stroke utilize a manual hands-on approach with little to no application of modern technology. As a result, physiotherapy treatment is lacking in availability, is highly subjective and can only employ very basic exercises. Increasing efforts are being made in the research and development of rehabilitation robots to address these issues. This research explores the use of an exoskeleton robot for physical rehabilitation of the human upper limb. Analysis of past exoskeleton designs have revealed major limitations in these exoskeletons' shoulder mechanism which limit the range of motion and the movements that can be performed on the shoulder. To overcome the shortcomings of past mechanism designs, a novel 4R mechanism is proposed. However, there are a range of kinematic designs of the 4R mechanism that can meet the performance requirements of a shoulder exoskeleton. To address this, a set of performance criteria are formulated and the NSGA II optimization algorithm is applied to identify an optimal design. The resulting 4R mechanism is capable of reaching the entire shoulder workspace with high performance and without mechanical interference. Performance comparisons with other shoulder mechanism designs confirm the optimized 4R mechanism has superior performance. The optimized 4R mechanism is then used to develop a 5 DOF active exoskeleton system for the shoulder and elbow joints. To maneuver the exoskeleton, an algorithm is developed to generate smooth point-to-point trajectories that are similar to the trajectories in normal human motion. This algorithm is further expanded into a trajectory planner which combines a sequence of point-to-point movements into a single smooth trajectory. To control the exoskeleton, two types of interactive control strategies are developed. Admittance control allows the user's limb to move the exoskeleton by applying forces at the designated interfaces, during which the exoskeleton can assist or resist user movement. Impedance control involves actuation of the exoskeleton to move the user's limb through a specified trajectory with an artificial compliance. Experimental results on a healthy human subject demonstrate the diverse capabilities of the exoskeleton. The tools developed in this research open up new possibilities in the field of physical rehabilitation.

Download or read book Development of an Adaptive Exoskeleton for Upper Arm Rehabilitaion written by Thisath Attampola Arachchige Don and published by . This book was released on 2021 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: Assistive technologies such as robotic and exoskeleton devices are utilized to aid in Activities of Daily Living (ADLs) and in rehabilitation tasks to alleviate and restore some of the lost degrees-of-freedoms (DOFs). However, most of the existing exoskeletons have alignment issues and limited functionality. The fitting and alignment of an exoskeleton with human anatomical joints and limbs are challenging, as the later has joints with a moving axis that generates complex motions. For instance, the shoulder joint does not have a fixed axis of rotation and has more than 3 DOFs, however most of the existing exoskeleton designs simplify the design by modeling the shoulder joint using ball and socket joint or three intersecting hinge joints. Such axes mismatches could cause severe pain and unconfort on the user. And this shows that a new design approach or a modification is needed to address such issues. This thesis is aimed at designing and testing new exoskeleton for upper arm rehabilitation. The designed exoskeleton is equipped with 5-DOF active joints; with four of them associated with the complex shoulder joint movements. The design is assessed for structural stability, functionality, ergonomics for fitting and alignments. The structural analysis was performed in CAD environment with finite element analysis and through prototype model. The effects of fitting and alignment were assessed through a three-stage ergonomic evaluation for the upper limb exoskeleton. The exoskeleton had an overall Rapid Upper Limb Assessment (RULA) score of 3. The effect of fitting and alignment has been assesed through musculoskeletal modeling in OpenSim and actual prototype testing, in both tests, upper arm muscles responded with a similar profile as the one without wearing exoskeleton, indicating that the exoskeleton did not cause any misalignment or out of plane pressure on the muscles.

Download or read book Development and Validation of a Low cost 3D Printed Upper Limb Prosthetic Simulator written by Christopher Copeland and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Background. The comparison of how prosthetic simulators and prosthetic devices influence contralateral brain activity may lead to a better understanding of the brain's ability to adapt to novel tools. Objective. The aim of the study was to determine if prosthetic simulators can emulate the neurological and neuromuscular responses seen in prosthesis use. Methods. In the present study, we utilized functional near-infrared spectroscopy (fNIRS) to evaluate the neural response in five children with a congenital upper limb reduction (ULR) using a body-powered prosthesis and five typically developing children(TD) using their non-preferred hand, as well as a prosthetic simulator on the same hand during a 60-second gross motor dexterity task. Results. Our data showed that the ULR group had lower activation within the primary motor cortex (M1) and supplementary motor area (SMA) compared to the TD group, but nonsignificant differences in the primary somatosensory area (S1). Compared to using their non-preferred hand, the prosthetic simulator in the TD group resulted in nonsignificant differences in M1 and SMA, but significantly higher S1 activation. Conclusion. These results indicate that prosthetic simulators may be unable to emulate the reduced degrees of freedom in individuals with upper limb reductions but provide similar afferent input conditions seen in prosthesis users.

Download or read book Development of a Prototype of an Active Exoskeleton of Upper Limb written by Nosiba Khougali and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Treatment of partial or full loss of function in upper limb due to spinal cord injuries, diseases, stroke or other health conditions require sophisticated intensive rehabilitation procedures of manipulative physiotherapy. Several mechanical devices and upper limb orthosis were designed to assist or augment upper limb function in some of these conditions. Active exoskeleton devices are effective technologies that can be used to compensate or assist body functions and provide sensing and support for non-functioned or partially functioned muscles. Moreover, they work as a robotic system to provide attachment framework for enabling patients to perform their daily tasks easily. This project aims to design and implement a simulated prototype of an active exoskeleton of the upper limb using NI LabVIEW 2014 software with one degree of freedom that represents elbow joint flexing/extension. This was performed using Fuzzy Logic control algorithm to estimate the movement position based on the sEMG signal. The data was recorded from the biceps brachii and triceps muscles of the subject during flexion and extension of elbow joint. The control method was established by extracting two time domain features of EMG which are Integrated EMG (IEMG) and Root Mean Square (RMS) from raw EMG datasets. The results show that the angle estimation can be performed using the time domain properties of EMG signal based on fuzzy logic system design. Also, the maximum value of the estimated angle was equal to 156 degrees while the actual angle was 170 degrees. Based on that, the estimated value of elbow joint angles was compared with the actual angle using fuzzy logic design in LabVIEW with approximately 70% correlation. Moreover, the high angle value obtained indicates that more pronounced EMG activity occurred with The RMS of biceps signal being synchronized with the angle of movement. Finally, the angular velocity obtained was positive with elbow flexing and negative with elbow extension.

Download or read book Development of an Upper Limb Robotic Device for Stroke Rehabilitation written by Elaine Chen Lu and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development O a Standard of Testing and Evaluation for 3D printed Pediatric Upper Limb Prosthetics written by Brendan Robert Lyle and published by . This book was released on 2017 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Torque Controlled Exoskeletons for Take home Upper Limb Rehabilitation written by Rafael Casas and published by . This book was released on 2022 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stroke is the leading cause for long term disability. There are approximately 800,000 new stroke cases every year in the US. Stroke survivors often face impairment in the upper extremity with reaching and grasping movements. Because the upper extremity is needed for activities of daily living (ADL) this becomes the focus of rehabilitation. A very high level of motor control is required before they can effectively use their upper limb in ADL. Hand motor control is usually the most limited and the probability of regaining functional use of their hand is low. Movement is impaired by hypertonia (increased passive resistance to movement), inability to activate extensors, and abnormal co-contraction of flexors. Highly repetitive arm and hand task practice has been found to be most effective for individuals with mild impairment. Practice is impossible if the patient is unable to complete the task. Exoskeletons can help patients with task practice as they apply forces that enable completion of movements that would otherwise be impossible. With exoskeletal support, the user will experience less fatigue with movements as less effort is required. In addition to the support offered by exoskeletons, home-based robotic therapy further enables repetitive task practice as it offers stroke survivors the ability to wear exoskeletons at home and integrate use of the upper limb into ADL. In addition to hand impairment, many stroke patients deal with an inability to extend their elbow when their shoulder is elevated against gravity. Proximal arm muscles and hand muscles are abnormally coupled, such that arm posture, activation level of proximal muscles, and lifting the arm against gravity can increase impairment in hand function. Many robotic treatments try to address this by providing the arm with partial support against gravity to facilitate the practice of reaching within a larger workspace. Thus, gravity compensation for the arm is predicted to improve functional ability in the entire limb. In order to enable gravity compensation, the CUA lab developed SpringWear, a wearable exoskeleton that allows stroke survivors to perform ADL with the impaired limb through reduced effort and improved kinematics. The shoulder mechanism balances the arm against gravity using a zero-rest length spring and an assistance profile that closely matches the gravity loading of the upper extremity. Assistance can be customized by adjusting the stiffness of the springs. SpringWear was designed for the home environment, enabling highly variable and meaningful task practice. The device provides assistance to forearm supination, elbow extension, and gravity compensation for the shoulder. SpringWear weighs 1.2 kg with a light-weight carbon fiber back splint as the base of the device and rubber bands as springs for assistance. While the rehab robotics field has made progress in improving hand and limb rehabilitation, gaps still exist in the wearability, usability, accessibility, and kinematics of exoskeletal devices. The rehabilitation robotics lab at Catholic University of America (CUA) previously developed the HandSOME, a passive, single degree of freedom (DOF), spring operated exoskeleton that assists patients in opening their affected hand. The second iteration of the design, HandSOME II, while still being passive and driven by rubber bands, provides more DOF and allows users to perform more complicated hand gestures. By building on previous research and development in the CUA lab, this doctoral research proposal consists of three projects with the goal of advancing the gaps in the rehab robotics field. 1. A one-day clinical study examined how effective the HandSOME II device was in reaching and grasping tasks and how it improved the range of motion with stroke users. 2. A longitudinal take-home study evaluated the effectiveness of home training for stroke subjects with the HandSOME II. The research explored gains though robotic therapy and results were quantified. 3. SpringWear was redesigned to focus on shoulder gravity compensation in order to improve its usability. Two passive joints were retained to allow free shoulder movement and assistance to shoulder elevation in any plane. Development will be followed by testing with stroke patients.

Download or read book Comprehensive Control Strategies for a Seven Degree of Freedom Upper Limb Exoskeleton Targeting Stroke Rehabilitation written by Levi Makaio Miller and published by . This book was released on 2012 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this dissertation control algorithms are developed and tested for the EXO-UL7 towards a control strategy for stroke rehabilitation. EXO-UL7 is a seven degree of freedom (Dof) powered upper limb exoskeleton that was initially designed at the University of Washington and further refined at the University of California Santa Cruz. Admittance control, swivel angle prediction and neural control of the device have been implemented and subjects tested performance of the device and control strategy. After an initial summery of the state of the art and details of the existing system. Each control strategy and performance from testing is explored. Admittance control uses force sensors on EXO-UL7 to control the movement of the device by moving in the direction that that user pressed on the device. Because EXO-UL7 is a redundant manipulator and supports the entire configuration of the arm, a single force sensor on the device end effector is not enough to fully define the movement. Additional force sensors on the device that are located at each attachment point of the machine interface allows for the full configuration of the device to be specified. This turns the under defined problem into an over defined problem (to many force signals for the number of Dof). Two strategies are developed to project the signals onto a seven degree subspace. The first adds the force vectors in task space then uses the Inverse kinematic to develop joint trajectories. The second uses the Jacoban transpose to map the forces first to instantaneous joint torques then the torques are added in joint space and finally joint trajectories are developed from joint torques. Six subjects performed a peg in hole experiment and it was found that task based admittance control had about 11\% lower interaction energy required to do the task. It was also shown that with both admittance controlers the subjects did the tasks slower then with no Control at all. Kinematic and dynamic constraints requced the bandwith of the system. To improve the bandwith, Predictive algorithms are employed. Swivel angle prediction is the first predictive algorithm implements to improve the performance of the device. With this control strategy the configuration of the redundant space is related to the end effector position. by observing human behavior it was noted that one of the fundamental task preformed by the human arm was to bring food to the mouth. By maximizing the manipulability of the device in the direction of the mouth, a simple stable closed form prediction of the configuration of the device was achived. Comparing movement from motion capture to predicted motion showed a good correlation and testing of the algorithm on the exoskeleton device was conducted. 4 Subjects conducted a peg in hole task. An 11.22\% reduction of interaction energy was achieved when compared to Admittance control alone. This algorthm can be used for motion folowwing as in teh current set up, or to predict where what the arm configuration should be when working with disabled populations. Although this method predicted motion very well, it only provided prodiction of the one Dof redundant space of the arm. To further extend the prediction capability and motion following of the device, neural control was implemented in which electro myography (EMG) is used to read the nerve impulsed to the muscle. Although this signal only relates muscle force to isometric muscle contraction, using other system parameters read from Exo-UL7 such as the joint, position and velocity, A Hill based muscle model predicts the muscle force and ultimately the muscle torque. Due to an inherent delay between when the nerve impulse can first be detected and when the muscle contracts (some where o the order of 50-100 ms) the motion can be predicted before the arm begins to move. The model has many variable that need to be predicted for each individual so before each subject test an parameter fitting is conducted. Four subjects preformed a peg in hole test. It was shown that the interaction power increased compared to admittance control, but the completion time decreased. With further examination in was noted that the interaction force and energy when using the neural control was the same as with the admittance control. This implies that with the same force we achieved a higher velocity, which means that the system had a higher overall gain. The performance gains were not uniform through out all the subjects. The parameter fit conducted for each subject did not guarantee convergence to even a local minimum and there is still opportunities to improve the system performance. Admittance control did a good job of motion following and neural and swivel prediction improved upon this control scheme. There is still further work to be done on the system. Currently using the systems that were build in this dissertation, a clinical trial for stroke rehabilitation is under way at the university of California San Fransisco.

Download or read book Wearable Robotics written by Jacob Rosen and published by Academic Press. This book was released on 2019-11-16 with total page 551 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wearable Robotics: Systems and Applications provides a comprehensive overview of the entire field of wearable robotics, including active orthotics (exoskeleton) and active prosthetics for the upper and lower limb and full body. In its two major sections, wearable robotics systems are described from both engineering perspectives and their application in medicine and industry. Systems and applications at various levels of the development cycle are presented, including those that are still under active research and development, systems that are under preliminary or full clinical trials, and those in commercialized products. This book is a great resource for anyone working in this field, including researchers, industry professionals and those who want to use it as a teaching mechanism. Provides a comprehensive overview of the entire field, with both engineering and medical perspectives Helps readers quickly and efficiently design and develop wearable robotics for healthcare applications

Download or read book Design and Development of a 7 Degree of freedom Powered Exoskeleton for the Upper Limb written by Joel C. Perry and published by . This book was released on 2006 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: