ExoTen-Glove: A Force-Feedback Haptic Glove Based on Twisted String Actuation System

Abstract

This paper presents a novel lightweight and simple TSA-based (twisted string actuation) wearable haptic glove (ExoTen-Glove). This system is using two independent twisted string actuators with integrated force sensors and small-size DC motors. The proposed system can provide users force feedback during the execution of grasping virtual objects. The design of the TSA-based ExoTen-Glove, description of the TSA system, the controller and the preliminary experimental evaluation of the proposed system has been presented in this paper. This device has been evaluated by an experiment in virtual reality environment using HTC VIVE headset with 2 degrees of freedom grasping tasks, where the participants were squeezing a real spring with their thumb and index finger and compare it with a virtual spring stiffness. The results prove the applicability of the ExoTen-Glove for rehabilitation and haptic purposes.

Wearable Soft Technologies for Haptic Sensing and Feedback

“…The development of small ratchets and pulleys helped to better transmit force to the fingers and to block unwanted motion. The use of flexible cables [ 117,118 ] ( Figure A) or twisted string actuators (TSA) [ 119 ] (Figure 9B) makes these systems feel soft and wearable.…”

“…Kinesthetic haptic feedback glove using A) electromagnetic motors with cables, [ 118 ] B) electromagnetic motors with TSA, [ 119 ] C) stacked DEAs [ 120 ] D) fluidic pneu‐Net actuators, [ 121 ] E) pneumatic McKibben actuators with cables, [ 122 ] and F) using electrostatic clutches. [ 11 ] (A) reproduced with permission.…”

“…[ 118 ] Copyright Contact Control Interface; (B) reproduced with permission. [ 119 ] Copyright 2018, IEEE; (C) reproduced with permission. [ 120 ] Copyright 2008, SPIE; (D) reproduced with permission.…”

“…[ 154,155 ] They can be divided into two main types. First, jointless gloves [ 117–119 ] use cables integrated within a textile glove to block or move fingers. They are small, light, and flexible, but require additional rigid structures to attach and actuate the cables (Figure 9D).…”

Hybrid Control Strategy for Force and Precise End Effector Positioning of a Twisted String Actuator

“…The high transmission ratio of TSAs is attractive for robotic systems [14,35], especially for applications where energy-efficient and costeffective solutions are required, such as robot manipulators [27,25] and grippers, anthropomorphic hands [15,22,20,34], and mobile robots [37], they provide lightweight and highly customizable solutions. Additionally, TSAs have been used successfully in functions that require compact and mechanically simple transmission with some level of compliance; among these, soft robotics [8] and human-machine interaction (HMI) devices like wearable robots and exoskeletons [36,4] or haptic devices [11,33,10,26].…”