A multi-stage design framework for the development of task-specific robotic exoskeletons

Abstract

This work presents a multi-stage design framework for developing robotic exoskeletons suited for specific tasks, such as individualized exercises that meet the needs of patients undergoing physical therapy. The framework systematically develops the exoskeleton based on the required task space, represented by a set of limb poses which may be defined directly, or indirectly using means such as motion capture. The design process seeks to maximize the poses inside and surrounding the defined task space whilst ensuring additional criteria required to perform the task are satisfied. A case study demonstrates the framework applied to develop two variations of shoulder exoskeleton suited for two specific upper limb activities. Prototype exoskeletons based on the framework's outcomes were constructed, and their suitability for use in their intended tasks were evaluated.

A framework for singularity-robust manipulator control during physical human-robot interaction

“…This provides an opportunity to develop a kinematic design that positions the singularities outside of the reachable workspace of the human operator, effectively ensuring they will not be reached during operation (Gupta et al, 2008). Design methods that optimize the mechanism to avoid singularity during operation have been proposed (Carmichael et al, 2015; Carmichael and Liu, 2014). Completely avoiding singularities for articulations such as the human shoulder which has a naturally large range of motion is challenging, with designs often settling for positioning singularities close to the edge of the workspace (Ball et al, 2007; Carignan et al, 2009; Perry et al, 2007).…”