Can Training Make Three Arms Better Than Two Heads for Trimanual Coordination?

Supernumerary effectors have been proposed to enable users to perform tasks alone that normally require assistance from a partner. While various supernumerary robotic limbs have been developed in the last decade, the capability of users to operate them effectively has not yet been proven. Here we tested whether users (i) can complete a task that requires simultaneous and fine control of three effectors, and (ii) can be trained to do so with similar or superior performance as through collaboration with a human partner. As in previous studies, initial augmented capability was less than that of working with a partner. However, one hour of dedicated solo trimanual training across three days significantly increased task performance, so that participants became able to perform trimanual control alone as well as or better than they could with a new partner. This shows the viability of augmentation systems for applications such as in robotic surgery or industrial assembly, which can be further validated on real tasks with physical systems.

A Three-Limb Teleoperated Robotic System with Foot Control for Flexible Endoscopic Surgery.

Flexible endoscopy requires a lot of skill to manipulate both the endoscope and the associated instruments. In most robotic flexible endoscopic systems, the endoscope and instruments are controlled separately by two operators, which may result in communication errors and inefficient operation. Our solution is to enable the surgeon to control both the endoscope and the instruments. Here, we present a novel tele-operation robotic endoscopic system commanded by one operator using the continuous and simultaneous movements of their two hands and one foot. This 13-degree-of-freedom (DoF) system integrates a foot-controlled robotic flexible endoscope and two hand-controlled robotic endoscopic instruments, a robotic grasper and a robotic cauterizing hook. A dedicated foot-interface transfers the natural foot movements to the 4-DoF movements of the endoscope while two other commercial hand interfaces map the movements of the two hands to the two instruments individually. An ex-vivo experiment was carried out by six subjects without surgical experience, where the simultaneous control with foot and hands was compared with a sequential clutch-based hand control. The participants could successfully teleoperate the endoscope and the two instruments to cut the tissues at scattered target areas in a porcine stomach. Foot control yielded 43.7% faster task completion and required less mental effort as compared to the clutch-based hand control scheme, which proves the concept of three-limb tele-operation surgery and the developed flexible endoscopic system.

Freeing the foot: integrating the foot core system into rehabilitation for lower extremity injuries.

The intrinsic muscles of the foot play a critical role in the regulation of absorption and propulsion during dynamic activities. Dysfunction of these may lead to an increased demand on the remaining components within the foot core system to maintain dynamic foot control, leading to a more rapid breakdown of these contributors and those proximal to the foot. Training the intrinsic foot muscles through a systematic progression of isolation via the short foot exercise offers the opportunity to reincorporate their contribution into the foot core system. This article discusses the function of the intrinsic foot muscles, their contributions to dynamic foot control, and a progressive training paradigm.