A modular wearable finger interface for cutaneous and kinesthetic interaction: control and evaluation

We present a modular wearable interface for haptic interaction and robotic teleoperation. It is composed of a 3-DoF fingertip cutaneous device and a 1-DoF finger kinesthetic exoskeleton, which can be used together as a single device or separately as two devices. The 3-DoF fingertip device is composed of a static body and a mobile platform. The mobile platform is capable of making and breaking contact with the fingertip and re-angle to replicate contacts with arbitrarily oriented surfaces. The 1-DoF finger exoskeleton provides kinesthetic force to the proximal and distal interphalangeal finger articulations using one servo motor grounded on the proximal phalanx. This paper presents the wearable device as well as three different position, force, and compliance control schemes, together with their evaluations. We also present three human subjects experiments, enrolling a total of 40 participants: the first experiment considered a curvature discrimination task, the second one a robot-assisted palpation task, the third one an immersive experience in Virtual Reality. Results showed that providing cutaneous and kinesthetic feedback significantly improved the performance of all the considered tasks. Moreover, although cutaneous-only feedback showed promising performance, adding kinesthetic feedback improved most metrics. Finally, subjects ranked our device as highly wearable, comfortable, and effective.