This research aims to design and implement a novel task-based knee rehabilitation strategy through kinematic synthesis, assist-as-needed control strategy, and recovery tracking system. Experimental kinematic data collected through motion capture system are utilized as an input to the mechanism synthesis procedure. Parallel mechanisms with single degree-of-freedom are considered to generate the complex three-dimensional (3D) motions of the lower leg. An exact workspace synthesis approach is utilized, in which the implicit description of the workspace is made to be a function of the structural parameters of the serial chains of the parallel mechanism, making it easy to relate those parameters to the desired trajectory from the motion capture. The synthesis procedure resulted an exoskeleton which can guide the complex motion of the human knee without the need of mimicking the joint by the exoskeleton counterpart. This can potentially reduce the improper alignment problems arising due to the constantly varying axis of rotation of human joint, which is often very difficult to predict. An assist-as-needed control and recovery tracking strategy is outlined based on an electromyography (EMG) signals and force sensing resistors (FSRs) mounted on the user and exoskeleton, respectively. The EMG signal is captured from the user leg and FSRs are applied at the attachment area of the exoskeleton and the leg, this helps to get the amount of force applied by the exoskeleton to the leg as well as for the recovery tracking. The assist-as-needed controller eliminates the need of constant supervision, and hence saves time and reduces cost of the rehabilitation process. Similarly, the real-time progress tracking system will motivate and actively engage users
This study is aimed at the design of a novel task-based knee rehabilitation device. The desired trajectories of the knee have been obtained through a vision-based motion capture system. The collected experimental kinematic data has been used as an input to a spatial mechanism synthesis procedure. Parallel mechanisms with single degree-of-freedom (DOF) have been considered to generate the complex 3D motions of the lower leg. An exact workspace synthesis approach is utilized, in which the parameterized forward kinematics equations of each serial chains of the parallel mechanisms are to be converted into implicit equations via elimination. The implicit description of the workspace is made to be a function of the structural parameters of the serial chain, making it easy to relate those parameters to the desired trajectory. The selected mechanism has been verified for the accuracy of its trajectory through CAD modeling and simulations. This design approach reduces alignment and fitting challenges in an exoskeleton as the mechanism does not require alignment of each robotic joint axis with its human counterpart.
This paper presents the design and control of a human prosthetic hand with an active palm roll joint. An active palm roll to a prosthetic hand will add a new degree-of-freedom, which can maximize the functionality and capability of performing complex tasks. The palm roll combined with the thumb allows the finger tips to touch one another and pinching to become a possible task for the user. In addition to maximizing the functionality of the hand, the inclusion of an active palm joint in the design provides a useful function for the design of prosthetics for children and the elderly who do not have enough upper arm strength to grasp objects firmly in their hand. The kinematics and workspace analyses of the pinky fingertips with the active palm joint and the thumb are also conducted in this study. With the added palm joint, the interaction of the workspace of the pinky fingertip and the thumb-tip is maximized, which allows grasping and manipulating different sizes and shapes of an object. Experiments are conducted to demonstrate the use of the active palm joint in grasping of objects.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.