Synthesis, Analysis, Design and Manufacturing of an Upper-Limb Rehabilitation Apparatus based on a Hoeken’s Four bar Linkage

Abstract

Over the last several decades robotic rehabilitation has played an important role in the human-robot interaction. This interaction is usually implemented by means of multi degree of freedom open kinematic chains mechanisms that are very complex and expensive. On the contrary, closed kinematic chains mechanisms based on four- and six bar linkages have only 1-DOF. Nevertheless, such mechanisms are capable of generating paths with complex kinematic characteristics. These mechanisms are preferable when simplicity and cost are the major criteria. These criteria are of higher importance when community based rehabilitation in developing countries is concerned. This capstone project is aimed at synthesizing, designing and manufacturing of such mechanism. The project is based on a 1-DOF mechanism, i.e. Hoeken four bar linkage. Major neurophysiological models related to upper-limb rehabilitation in people after strokes, such as Minimum Jerk Model, Fitts’s Law and Just Noticeable Difference are considered in this paper. The methodology includes developing kinematic, kinetostatic and dynamic analysis of the mechanism along with control and mechatronics concepts. The analysis and concepts derived in this paper are used for patients’ training procedures.