Development of 3-D printed exohand for mirror therapy

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Thesis Type: Postgraduate

Institution Of The Thesis: Middle East Technical University, Graduate School of Natural and Applied Sciences, MAKİNE MÜHENDİSLİĞİ ANABİLİM DALI, Turkey

Approval Date: 2022

Thesis Language: English

Student: TUNAHAN YILMAZ

Supervisor: ALİ EMRE TURGUT

Open Archive Collection: AVESIS Open Access Collection

Abstract:

This thesis presents the modelling and design of a family of exoskeleton mechanisms to be used in post-stroke rehabilitation therapy. The mechanism in question is an exoskeleton worn on the index finger, and it aims to support the fingers of patients who have lost their mobility after paralysis, like a physiotherapist, and to improve motor learning in the patient in this process. Based on motor learning principles, an underactuated mechanism design has been created for this purpose, allowing the patient to make mistakes while also encouraging him to expand the search space. A wide range of phalanges sizes was considered within the design function to reduce the effect of finger sizes on the mechanism. Within the mechanism family, there are fully-actuated and under-actuated versions. While obtaining a fully-actuated design output, it is desired to keep the task space of the mechanism wide. The Global Isotropy Index was used as the metric controlling the end effector's manipulability for this purpose. The Genetic Algorithm toolbox of the MATLAB program was used for mechanism optimization. After obtaining the output for the fully-actuated mechanism, the evolution of this obtained design into the under-actuated versions was carried out. The Virtual Work method is used to analyse the under-actuated mechanism by obtaining force equations. A method for this transition that is expected to be easily realized is also presented. Following the design, the mechanism was manufactured and tested.