Download or read book A Framework for Whole Body Augmentative Exoskeleton Control written by Orion Hubert Campbell (IV) and published by . This book was released on 2018 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, I present two primary contributions towards more capable augmentative exoskeleton systems including (1) the design and implementation of a robot-agnostic, high-level control infrastructure for better real-time performance and (2) a cohesive framework for whole-body augmentative exoskeleton control in a high-degree-of-freedom (dof) exoskeleton system. Both contributions were part of a larger project, in which our team designed and built a form-fitting lower-body augmentative exoskeleton with the objective to enhance a pilot's load carrying ability without sacrificing speed or maneuverability. Modern high-level control systems require excellent timing and low communication latencies to ensure stable, robust, and high-performance multijoint control. Towards this end, I designed and implemented a nodelet-based high-level controller wrapper that abstracts away and optimizes many of the implementation details involved in building such a control infrastructure. My first iteration of improvements used ROS's (Robot Operating System) intraprocess communication protocol along with proper integration of our RT-preempt kernel to ensure reliable, low-jitter timing performance and low-latency communication. I then helped to design infrastructure improvements that further reduced round-trip times via full system synchronization. My high-level control infrastructure has enabled significant advances for a variety of projects in the Human-Centered Robotics Lab (HCRL), including the development of a controller for an augmentative exoskeleton and dynamic walking using the lab's point-foot bipedal robot, Mercury. The second major contribution in this thesis is an algorithm that I developed for whole-body augmentative exoskeleton control. It uses a model of the exoskeleton to cancel static, gravitational loads, and measured cuff forces to attenuate human-exo interaction forces, including inertial loads and those caused by disturbances from the environment. The key contribution of this control scheme relative to other exoskeleton transparency controllers is how this algorithm (1) handles contact switching given the corresponding discrete changes in the dynamics and (2) routes the needed reaction forces to the ground given the underactuated, floating-base dynamics with contact constraints. I formulate a Quadratic Programming (QP) optimization problem to solve for permissible reaction forces and actuator torques that come as close as possible to providing the desired dynamic attenuation behavior of the controller while also satisfying wrench-cone constraints for each of the exoskeleton's contacts. A relaxation variable, penalized in the cost function, ensures the solver can always find a feasible solution, and cost function weights penalizing contact point accelerations and reaction force magnitudes are smoothly interpolated to ensure continuous torque commands as the system switches between two discrete sets of contacts

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 Control Strategies for Robotic Exoskeletons to Assist Post Stroke Hemiparetic Gait written by Julio Salvador Lora Millán and published by Springer Nature. This book was released on with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Shaping Control of Powered Lower limb Exoskeletons for Assistance of Human Locomotion written by Ge Lv and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The majority of powered lower-limb exoskeletons nowadays are designed to rigidly track time-based kinematic patterns, which forces users to follow specific joint positions. This kinematic control approach is limited to replicating the normative joint kinematics associated with one specific task and user at a time. These pre-defined trajectories cannot adjust to continuously varying activities or changes in user behavior associated with learning during gait rehabilitation. Time-based kinematic control approach must also recognize the user’s intent to transition from one task-specific controller to another, which is susceptible to errors in intent recognition and does not allow for a continuous range of activities. Moreover, fixed joint patterns also do not facilitate active learning during gait rehabilitation. People with partial or full volitional control of their lower extremities should be allowed to adjust their joint kinematics during the learning process based on corrections from the therapist. To address this issue, we propose that instead of tracking reference kinematic patterns, kinetic goals (for example, energy or force) can be enforced to provide a flexible learning environment and allow the user to choose their own kinematic patterns for different locomotor tasks. In this dissertation, we focus on an energetic control approach that shapes the Lagrangian of the human body and exoskeleton in closed loop. This energetic control approach, known as energy shaping, controls the system energy to a specific analytical function of the system state in order to induce different dynamics via the Euler-Lagrange equations. By explicitly modeling holonomic contact constraints in the dynamics, we transform the conventional Lagrangian dynamics into the equivalent constrained dynamics that have fewer (or possibly zero) unactuated coordinates. Based on these constrained dynamics, the matching conditions, which determine what energetic properties of the human body can be shaped, become easier to satisfy. By satisfying matching conditions for human-robot systems with arbitrary system dimension and degrees of actuation, we are therefore able to present a complete theoretical framework for underactuated energy shaping that incorporates both environmental and human interaction. Simulation results on a human-like biped model and experimental results with able-bodied subjects across a variety of locomotor tasks have demonstrated the potential clinical benefits of the proposed control approach.

Download or read book Whole Body Control for Multi Contact Balancing of Humanoid Robots written by Bernd Henze and published by Springer Nature. This book was released on 2021-11-03 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book aims at providing algorithms for balance control of legged, torque-controlled humanoid robots. A humanoid robot normally uses the feet for locomotion. This paradigm is extended by addressing the challenge of multi-contact balancing, which allows a humanoid robot to exploit an arbitrary number of contacts for support. Using multiple contacts increases the size of the support polygon, which in turn leads to an increased robustness of the stance and to an increased kinematic workspace of the robot. Both are important features for facilitating a transition of humanoid robots from research laboratories to real-world applications, where they are confronted with multiple challenging scenarios, such as climbing stairs and ladders, traversing debris, handling heavy loads, or working in confined spaces. The distribution of forces and torques among the multiple contacts is a challenging aspect of the problem, which arises from the closed kinematic chain given by the robot and its environment.

Download or read book A Lower body Exoskeleton Simulation and Control Framework Based on Deep Reinforcement Learning written by Lowell Rose and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stroke is a leading cause of disability, and post-stroke individuals often experience hemiparesis, which can result in compensatory movements that affect their overall gait pattern. Lower-body exoskeletons allow for repetitive, intense, and task-based practice of movement patterns that can promote gait recovery. Validating exoskeleton gait patterns in simulation is vital for ensuring patient safety and comfort; however, current simulation tools possess challenges in controlling exoskeleton hardware. Additionally, present model-based adaptive controllers rely on complex dynamics models for the user and exoskeleton that are difficult to accurately define. In this thesis, a centralized exoskeleton simulation and control framework is presented, where desired gait patterns can be validated and customized on-the-fly in physiotherapy sessions. A model-free, end-to-end deep reinforcement learning controller is also presented, to allow for exoskeleton control that is robust to desired gait patterns and a user's interaction with the device. Several experiments were conducted to validate these approaches.

Download or read book Control Strategies for Series Elastic Multi contact Robots written by Gray Cortright Thomas and published by . This book was released on 2019 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: As robots designed for physical interaction with humans---humanoids, exoskeletons and beyond---make their entrance into society, understanding the limitations of their interaction behavior will be key to their effective use. The state of the art method for allowing such systems to be both compliant and force sensitive is to introduce mechanical springs into the joints of these robots, making them "series elastic". But this complicates the control of these robots, making it hard to separate truth from optimism in what they will be able to accomplish using feedback control. Robots are programmed in hierarchical layers, and each layer makes assumptions about the layer below it. The planning layer assumes the plan will be followed. The whole body controller layer assumes the actuators will supply whatever torque it specifies. And the actuator control layer assumes the actuator behaves like a linear system. This dissertation studies the interfaces between these layers as they are influenced by the choice to include series elastic actuation, hoping to resolve the mismatch between assumptions and guarantees that arise from this choice. These questions lead it naturally to the lowest of the layers, where a new system identification system allows the actuator to assume a bounded uncertainty model. The dissertation then refines the insights from studying uncertain SEA models into a simpler model that explains the most important factors. It uses this to design SEA controllers that go beyond the traditional limits of passivity. These insights also apply to the problem of strength augmentation exoskeleton control. Factor of 3 amplification results are reported on a tethered, 12 degree of freedom, powered, lower body exoskeleton with four passive joints using a simplified version of the controller and a far more advanced whole body control framework. These ideas are introduced in the context of the authors's work with various testbeds and state of the art robots including a point foot biped, the DARPA virtual robotics challenge simulator, the NASA R5 Valkyrie Humanoid, and the Apptronik Sagittarius Lower Body Exoskeleton

Download or read book Exoskeletons in Rehabilitation Robotics written by Eduardo Rocon and published by Springer. This book was released on 2011-02-02 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: The new technological advances opened widely the application field of robots. Robots are moving from the classical application scenario with structured industrial environments and tedious repetitive tasks to new application environments that require more interaction with the humans. It is in this context that the concept of Wearable Robots (WRs) has emerged. One of the most exciting and challenging aspects in the design of biomechatronics wearable robots is that the human takes a place in the design, this fact imposes several restrictions and requirements in the design of this sort of devices. The key distinctive aspect in wearable robots is their intrinsic dual cognitive and physical interaction with humans. The key role of a robot in a physical human–robot interaction (pHRI) is the generation of supplementary forces to empower and overcome human physical limits. The crucial role of a cognitive human–robot interaction (cHRI) is to make the human aware of the possibilities of the robot while allowing them to maintain control of the robot at all times. This book gives a general overview of the robotics exoskeletons and introduces the reader to this robotic field. Moreover, it describes the development of an upper limb exoskeleton for tremor suppression in order to illustrate the influence of a specific application in the designs decisions.

Download or read book Force Control Theory and Method of Human Load Carrying Exoskeleton Suit written by Zhiyong Yang and published by Springer. This book was released on 2017-04-06 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reports on the latest advances in concepts and further development of principal component analysis (PCA), discussing in detail a number of open problems related to dimensional reduction techniques and their extensions. It brings together research findings, previously scattered throughout many scientific journal papers worldwide, and presents them in a methodologically unified form. Offering vital insights into the subject matter in self-contained chapters that balance the theory and concrete applications, and focusing on open problems, it is essential reading for all researchers and practitioners with an interest in PCA

Download or read book Wearable Robots written by José L. Pons and published by John Wiley & Sons. This book was released on 2008-04-15 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: A wearable robot is a mechatronic system that is designed around the shape and function of the human body, with segments and joints corresponding to those of the person it is externally coupled with. Teleoperation and power amplification were the first applications, but after recent technological advances the range of application fields has widened. Increasing recognition from the scientific community means that this technology is now employed in telemanipulation, man-amplification, neuromotor control research and rehabilitation, and to assist with impaired human motor control. Logical in structure and original in its global orientation, this volume gives a full overview of wearable robotics, providing the reader with a complete understanding of the key applications and technologies suitable for its development. The main topics are demonstrated through two detailed case studies; one on a lower limb active orthosis for a human leg, and one on a wearable robot that suppresses upper limb tremor. These examples highlight the difficulties and potentialities in this area of technology, illustrating how design decisions should be made based on these. As well as discussing the cognitive interaction between human and robot, this comprehensive text also covers: the mechanics of the wearable robot and it’s biomechanical interaction with the user, including state-of-the-art technologies that enable sensory and motor interaction between human (biological) and wearable artificial (mechatronic) systems; the basis for bioinspiration and biomimetism, general rules for the development of biologically-inspired designs, and how these could serve recursively as biological models to explain biological systems; the study on the development of networks for wearable robotics. Wearable Robotics: Biomechatronic Exoskeletons will appeal to lecturers, senior undergraduate students, postgraduates and other researchers of medical, electrical and bio engineering who are interested in the area of assistive robotics. Active system developers in this sector of the engineering industry will also find it an informative and welcome resource.

Download or read book Novel Control for a Post Stroke Gait Rehabilitation Exoskeleton written by Robert Trott and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stroke is the second highest cause of death worldwide and the third leading cause of adult disability across all age brackets. Recovering gait following stroke is a major goal of patients, and hence rehabilitation, as it is central to many activities of daily living. Of the different treatment modalities, robotic assisted gait training is growing in popularity, but is still considered complementary to, and not substitute for conventional therapies comprising physiotherapy, overground walking and body weight supported treadmill training. The potential advantages that lower limb robotics bring to neurorehabilitation over conventional therapies include, higher dosage, specificity, improved consistency, and duration, though these benefits have been slow to manifest. Exoskeletons are well placed to provide these benefits, as well as environmental variation and task salience if they can be used away from outpatient settings. Control strategies that may be enhancing of recovery are often confined to stationary exoskeletons, and the control of mobile exoskeletons is only loosely related to gait, if at all, which limits rehabilitation outcomes. -- The primary aim of this PhD thesis was to develop an adaptive, user-initiated gait Controller that aims to target a novel neural recovery pathway. The Controller would use a robotic exoskeleton, with the intention of developing novel neuroplasticity that is beneficial for gait and would be permissive of simultaneous control of hip and knee posture. A theoretical framework based on the principles of neuroplasticity was proposed that seeks to bring higher engagement, task variance, and volition to gait rehabilitation. This framework considers stroke and rehabilitation timelines and the interaction of the proposal with existing theory, how beneficial neuroplasticity may manifest, and how the proposal may be detrimental. A comprehensive survey of candidate lower limb devices followed (164 devices), to understand exactly what features are compatible, complementary, or contradictory to the proposed control method, and to understand the implications the various specifications have. Specifically, it was found that ambulating exoskeletons that can move around the environment were preferred for their ability to be used in the community and the home, and that extended joint range of motion will be permissive of activities that are supportive of gait such as sit-to-stand and stair ascent/descent. Of the various control systems that have been implemented with exoskeleton devices, trajectory control, where motion is enforced on the limb by the exoskeleton, is preferred. -- The method of control was assessed for suitability as a gait controller through a participant study (n = 21). Participants were asked to reproduce the motion required for the controller, and with minor modification to participant motion it was shown that reliable control signals can be obtained. The remainder of the thesis applies the learnings of the previous stages in the development of the Controller and an accompanying Sensor. The custom Sensor was designed with a small form factor to be applied on the Controller. The thesis concludes with an implementation of the Controller and a successful demonstration of the proposed concept, where the control signals are reproduced on a scale lower limb exoskeleton. The full technical detail and specification of the Controller, and the custom position Sensor developed specific for this application, are presented as part of this work. -- This work has added a new theoretical framework for gait control following stroke and has added technological capability to implement the proposal. It is the primary recommendation of this PhD that the novel control method be tested further with participant studies and that the component hardware be developed further. Therapies targeting novel recovery mechanisms breathe fresh air into rehabilitation and may inspire other new treatments, and future funded work originating from this PhD will see the concept tested with a chronic stroke population, using an ambulating exoskeleton and the Controller.

Download or read book Wearable Exoskeleton Systems written by Shaoping Bai and published by Control, Robotics and Sensors. This book was released on 2018 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wearable exoskeletons are electro-mechanical systems designed to assist, augment, or enhance motion and mobility in a variety of human motion applications and scenarios. The applications, ranging from providing power supplementation to assist the wearers to situations where human motion is resisted for exercising applications, cover a wide range of domains such as medical devices for patient rehabilitation training recovering from trauma, movement aids for disabled persons, personal care robots for providing daily living assistance, and reduction of physical burden in industrial and military applications. The development of effective and affordable wearable exoskeletons poses several design, control and modelling challenges to researchers and manufacturers. Novel technologies are therefore being developed in adaptive motion controllers, human-robot interaction control, biological sensors and actuators, materials and structures, etc. In this book, the editors and authors report recent advances and technology breakthroughs in exoskeleton developments. It will be of interest to engineers and researchers in academia and industry as well as manufacturing companies interested in developing new markets in wearable exoskeleton robotics.

Download or read book Mathematical Models of Exoskeleton written by Andrey Valerievich Borisov and published by Springer Nature. This book was released on 2022-03-31 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the current state of the problem of describing the musculoskeletal system of a person. Models of the destruction of the endoskeleton and the restoration of its functions using exoskeleton are presented. A description is given of new approaches to modeling based on the use of weightless rods of variable length with concentrated masses. The practical application to the tasks of numerical simulation of the movements of the musculoskeletal system of a person is described. Exoskeleton models with variable-length units based on absolutely hard sections and sections that change their telescopic type length have been developed. The book is intended for specialists in the field of theoretical mechanics, biomechanics, robotics and related fields. The book will be useful to teachers, as well as graduate students, undergraduates and senior students of higher educational institutions, whose research interests lie in the modeling of anthropomorphic biomechanical systems.

Download or read book Lower Body Exoskeleton for Walking Gait Assistance and Performance Augmentation Using Compliance Controlled Actuators written by Nelson Rafael Simoes Costa and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Robotic Assistive Technologies written by Pedro Encarnação and published by CRC Press. This book was released on 2017-02-03 with total page 341 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains a comprehensive overview of all current uses of robots in rehabilitation. The underlying principles in each application are provided. This is followed by a critical review of the technology available, of the utilization protocols, and of user studies, outcomes, and clinical evidence, if existing. Ethical and social implications of robot use are also discussed. The reader will have an in depth view of rehabilitation robots, from principles to practice.

Download or read book Development of an Upper body Robotic Rehabilitation Platform that Furthers Motor Recovery After Neuromuscular Injuries written by Bongsu Kim and published by . This book was released on 2016 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation presents the development of an upper-body exoskeleton and its control framework for robotic rehabilitation of the arm and shoulder after a neurological disorder such as a stroke. The first step is designing an exoskeleton hardware that supports natural mobility of the human upper body with a wide range of motion for enabling most rehabilitation exercises. The exoskeleton is equipped with torque-controllable actuation units for implementing various robotic rehabilitation protocols based on force and impedance behaviors. The control framework is designed to exhibit a highly backdrivable behavior with a gravity compensation for the robot's weight and optional gravity support for user's arm weight to promote voluntary movements of patients with motor impairments. The control framework also serves as a `substrate' of other robotic control behaviors for rehabilitation exercises by superimposing desired force or impedance profiles. A stability analysis is performed to examine the coupled stability between the robot and human. After designing the hardware and control, several experiments are carried out to test the mobility and dynamic behavior of the robot. Lastly, a human subject study evaluates the effectiveness of the robot's shoulder mechanism and control algorithm in assisting the coordination around the shoulder. The results show that the robot induces desirable coordination in the presence of abnormalities at the shoulder.

Download or read book Investigation of Triceps Surae Loading and Coordination During Exoskeleton assisted Gait with Non invasive Wearable Sensing of Tendon Force written by Dylan G. Schmitz and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Exoskeletons which provide supplemental plantarflexion torque about the ankle are designed to offload the triceps surae and are able to reduce the energy cost of walking and running. However, the biomechanical adaptations which underly these whole-body metabolic changes are not well-understood. Furthermore, differences in individual responses to exoskeleton assistance are a major hurdle to wide deployment of these devices, and current techniques have provided little insight into why some users receive little-to-no benefit despite hours of training and optimization of the exoskeleton assistance. Triceps surae muscle-tendon behavior is known to adapt in the presence of external plantarflexion torque, but inverse dynamics is insufficient to isolate contributions to the net ankle torque. Shear wave tensiometry is a tool which can directly quantify changes in soft tissue loading during dynamic activities. As such, the first objective of this thesis was to investigate changes in triceps surae muscle-tendon loading with exoskeleton assistance and to characterize individual adaptation strategies using shear wave tensiometry. The second objective was to develop advanced shear wave tensiometry techniques and algorithms for use in exoskeleton characterization, user training, and control. I first used tensiometry to characterize changes in Achilles tendon loading during walking with powered and passive exoskeletons, during which I observed individual differences in adaptation which were distinct from predictions of triceps surae forces using inverse dynamics. From this, I concluded that Achilles tendon loading could be used to categorize responses to exoskeleton assistance and may provide a framework for improved user training. These findings inspired a number of improvements to the shear wave tensiometry methodology. Addressing the challenges of signal reliability and sensor miniaturization, I implemented a Kalman filtering process to reject noise and decorrelation errors inherent to measurements of wave propagation and implemented algorithms for use with tensiometer sensor arrays with one or multiple measurement point(s). Finally, I developed and implemented a real-time computation and visualization paradigm for tensiometry which can be used for biofeedback, and eventually, closed loop control of exoskeleton assistance. These enhancements are pivotal for future work which will explore the use of tendon loading biofeedback as a tool for rapid and customized training for exoskeleton use. We conclude that variability in responses to exoskeleton assistance is a result of individual musculoskeletal adaptations which can be understood with direct measured of the underlying forces using shear wave tensiometry.