Control of a Supernumerary Robotic Hand by Foot: An Experimental Study in Virtual Reality

Abstract

In the operational theater, the surgical team could highly benefit from a robotic supplementary hand under the surgeon’s full control. The surgeon may so become more autonomous; this may reduce communication errors with the assistants and take over difficult tasks such as holding tools without tremor. In this paper, we therefore examine the possibility to control a third robotic hand with one foot’s movements. Three experiments in virtual reality were designed to assess the feasibility of this control strategy, the learning curve of the subjects in different tasks and the coordination of foot movements with the two natural hands. Results show that the limbs are moved simultaneously, in parallel rather than serially. Participants’ performance improved within a few minutes of practice without any specific difficulty to complete the tasks. Subjective assessment by the subjects indicated that controlling a third hand by foot has been easy and required only negligible physical and mental efforts. The sense of ownership was reported to improve through the experiments. The mental burden was not directly related to the level of motion required by a task, but depended on the type of activity and practice. The most difficult task was moving two hands and foot in opposite directions. These results suggest that a combination of practice and appropriate tasks can enhance the learning process for controlling a robotic hand by foot.

Playing the piano with a robotic third thumb: Assessing constraints of human augmentation

“…Carrozza et al, 2007;Abdi et al, 2015;Dougherty and Winck, 2019). Abdi et al (2015) study the control of a third robotic hand via the foot in virtual reality, for robotic surgery applications, showing similar learning trends to what we observe here. Results obtained with adaptive foot interfaces for robot control (e.g.…”

In a demanding task, three-handed manipulation is preferred to two-handed manipulation

“…Two minutes of practice was not enough for developing the sense of ownership towards the third hand. In our previous experiment with three different virtual games 35 , we observed that the sense of ownership towards the third hand improved constantly through the games. Also, performing different types of three handed tasks may enhance the ownership.…”

Ownership and Agency of an Independent Supernumerary Hand Induced by an Imitation Brain-Computer Interface

“…The feeling of an independent supernumerary limb has been presented in a medical case study [8], but recent advances in robotics and computer science suggest that artificial supernumerary limbs could be incorporated into healthy human function in the future. Supernumerary robotic limbs can be built to assist human movements [9,10] and brain-computer interfaces have been shown to work during concurrent movement execution [11]. It is therefore important to understand if the brain is capable of feeling ownership over additional and independent supernumerary limbs and agency over their actions.…”