Semi-Autonomous Control Development of a Prosthetic Limb for Above-elbow Amputation

Abstract

In this paper, we propose a new approach for semi-autonomous control of an above-elbow prosthetic limb during the reaching task for object grasping, utilizing IMU and computer vision technology. The proposed method addresses the challenge of controlling prosthetic limbs for individuals with transhumeral amputations. These individuals often have insufficient muscle signals to control all the joints of a limb with multiple degrees of freedom. The method aims to assist individuals with upper limb amputations in reaching for and grasping desired objects in a specific direction. This method can take advantage of the ongoing technological advancements in prosthetic limbs, particularly in terms of the increasing number of degrees of freedom for movement. This technology enables amputees to synchronize the movement of their prostheses with that of their shoulder joint, resulting in a more natural behavior when grasping objects. A robotic arm with seven degrees of freedom and a camera, was simulated in the Webots environment. The arm was then connected to the MATLAB environment to execute the proposed algorithm for reaching a desired object. The algorithm's performance was evaluated practically using a seven-degree-of-freedom experimental manipulator, a camera, and a one-degree-of-freedom gripper. The first three joints in the arm are the shoulder joints, which are controlled by the user, while the remaining joints are part of the prosthetic limb. The practical results demonstrate the effectiveness of the proposed method in enabling amputees to reach for and grasp desired objects simultaneously using shoulder movements. The estimated time to complete this task varies between 3 and 4 seconds, depending on the specific case.