Conceptualization of Design of Prosthetic Robotic Linkage for Human Limb Rehabilitation

The first phase work of the project involving the conceptualization of mechanical design of an active knee prosthesis linkage mechanism is proposed in this paper. For patients needing limb movement rehabilitation with impaired upper or lower limb joint functions and also for otherwise healthy persons suffering muscle weakness syndrome, this paper proposes an active linkage mechanism along with its actuation. The aim of this study is to demonstrate a theoretical basis for the design of linkage mechanism having stance phase control as well as swing phase fluidic kinematic behavior in conformity with natural legs. Proposed “Knee Mimicking Prosthetic Robotic Linkage Mechanism (KMPRLM) for Human Joint” will have flexion angle up to 60°.This paper includes the conceptual design of “Knee Mimicking Prosthetic Robotic Linkage” which will be used for rehabilitative and assistive purposes. The mechanical design of knee prosthesis linkage mechanism, its mathematical modeling and kinematical analysis is outlined here. .It is to be worn on lateral side of lower or upper limb and will provide naturalistic movement of elbow or leg joint. Linear actuator based motion is proposed which can be further put under myoelectric control. KMPRL is designed to follow the trajectory tracking which corresponds to a typical rehabilitation exercise and is an able knee mimicking assistive device .Thus confirming to effectiveness in rehabilitation therapy and post-surgery recovery treatment. While earlier generation limb rehabilitation used dead weight passive attachment, the proposed KMPRL has advantage because it is an active device linkage mechanism. This can be very conveniently used in the active rehabilitation and therefore resulting in shortening of recovery period of a patient. In this paper first phase of research project work comprising of conceptualization of design, prototype development of an active knee prosthesis linkage mechanism as proof of concept has been presented . The proposed prototype is to act as test bed for further improvement, analysis and refinement and optimizations.