Design and performance analysis of a 3-RRR spherical parallel manipulator for hip exoskeleton applications

• Published in: Journal of rehabilitation and assistive technologies engineering Vol. 4; p. 2055668317697596
• Main Authors: Sadeqi, Soheil, Bourgeois, Shaun P, Park, Edward J, Arzanpour, Siamak
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.01.2017; Sage Publications Ltd
• Subjects: Original; dexterity; rotational sensitivity; spherical parallel manipulator; inverse kinematics; Jacobian; Hip exoskeleton; manipulability; experimental data
• ISSN: 2055-6683
• DOI: 10.1177/2055668317697596

This paper presents the design and performance analysis and experimental study of a 3-RRR spherical parallel manipulator in the context of hip exoskeleton applications. First, the mechanism’s inverse kinematics analysis and Jacobian matrix development are revisited. Manipulability, dexterity, and rotational sensitivity indices are then evaluated for two different methods of attachment to the human body. The superior attachment method in terms of these performance measures is indicated, and an experimental study based on the selected method is conducted; the experiment involves testing the capability of a 3-RRR manipulator’s end-effector in tracking the motions experienced by a human hip joint during normal gait cycles. Finally, the results of the experimental study indicate that the manipulator represents a feasible hip exoskeleton solution providing total kinematic compliance with the human hip joint’s 3-degree-of-freedom motion capabilities.