Zohaib Aftab This email address is being protected from spambots. You need JavaScript enabled to view it.1, Faraz Shafi1 , Rizwan Shad2 , Rana Inzimam-ul-Haq1 , and Kashif Saeed3

1Faculty of Engineering, University of Central Punjab Lahore and the Human-centered robotics lab, National Center of Robotics and Automation, Pakistan, 1 Khayaban-e-Jinnah, Johar Town Lahore Pakistan
2Faculty of Engineering, University of Central Punjab Lahore
3Department of Electrical Engineering, FAST-NUCES Pakistan


Received: October 24, 2020
Accepted: January 7, 2021
Publication Date: August 1, 2021

 Copyright The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are cited.

Download Citation: ||https://doi.org/10.6180/jase.202108_24(4).0001  


Powered exoskeletons are wearable robotic devices intended to provide extra power to ailing limbs during walking. The selection of appropriate motor and transmission is essential in enhancing the power-to-weight ratio of the system while keeping the cost down. This article presents a systematic method to size the motortransmission unit by taking into account the motor’s characteristics, transmission inertia, efficiency and cost of the system. Since a lower-limb exoskeleton system is designed for walking, clinical gait analysis data is used to assess the dynamic load requirements. An optimal selection of the motor and gearhead is made to power the hip joint of the exoskeleton. Choice of the motor-reducer unit is compared using different criteria such as maximizing load acceleration or peak power. The framework can be easily extended to other joints as well as to other types of exoskeletons.

Keywords: Rehabilitation robotics; Motor sizing; Transmission selection; Assistive robots.


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