A novel haptic glove (ExoTen-Glove) based on Twisted String Actuation (TSA) system for virtual reality

A compact and light-weight wearable haptic glove (ExoTen-Glove) based on Twisted String Actuation (TSA) system is presented in this paper. The proposed system uses two actuators with small size DC motors and an integrated force sensor based on optoelectronic components. ExoTen-Glove can provide force feedback to the thumb on one side, and to the other fingers grouped together on the other side. This configuration has been selected to provide the user force feedback during the execution of grasping tasks by means of a virtual reality environment to feel the stiffness of different objects. Thus for the first evaluation of the ExoTen-Glove, we only focus on the feedback from thumb and index finger. The paper reports the design of the haptic glove, the description of the actuation system, the embedded controller, and the preliminary experimental evaluation of the device. The ExoTen-Glove has been evaluated by means of a simple experiment in virtual environment with 2-DOF grasping activities of rigid and compliant virtual object (spring) using thumb and index finger to show the applicability of the system for rehabilitation and haptic feedback purposes. Results of the experiments showed that the haptic ExoTen-Glove improved stiffness evaluation significantly for the high and low spring stiffness and users were able to distinguish virtual spring stiffness differences easily with high accuracy.