Exploiting Intrinsic Kinematic Null Space for Supernumerary Robotic Limbs Control

TL;DR

This paper presents a novel control strategy for supernumerary robotic limbs that leverages the intrinsic kinematic null space of the human kinematic chain, enhancing intuitive control and task performance.

Contribution

It introduces a control method exploiting the human kinematic null space for supernumerary limb coordination, improving intuitiveness and effectiveness in complex tasks.

Findings

Effective control of supernumerary robotic finger demonstrated

Practice enhances user control ability

Control strategy supports complex task execution

Abstract

Supernumerary robotic limbs (SRLs) gained increasing interest in the last years for their applicability as healthcare and assistive technologies. These devices can either support or augment human sensorimotor capabilities, allowing users to complete tasks that are more complex than those feasible for their natural limbs. However, for a successful coordination between natural and artificial limbs, intuitiveness of interaction and perception of autonomy are key enabling features, especially for people suffering from motor disorders and impairments. The development of suitable human-robot interfaces is thus fundamental to foster the adoption of SRLs. With this work, we describe how to control an extra degree of freedom by taking advantage of what we defined the Intrinsic Kinematic Null Space, i.e. the redundancy of the human kinematic chain involved in the ongoing task. Obtained results demonstrated that the proposed control strategy is effective for performing complex tasks with a supernumerary robotic finger, and that practice improves users' control ability.