Design and development of a lightweight, low-cost cylindrical electrostatic clutch

Abstract

Electrostatic clutches have the potential to enhance the functionality of actuators in the field of robotic industries, offering benefits such as heightened precision, rapid response times, and improved energy efficiency. These clutches serve as flexible, lightweight, and cost-effective mechanisms that find applications in a variety of force-dependent tasks, including robotic grippers, clamping systems, holding fixtures, lifting and hoisting equipment, and VR haptic gloves. However, incorporating these clutches into practical designs has proven to be challenging due to the inherent variability in holding forces and its range caused by the changing position of the moving electrodes and the corresponding overlapping areas. To address this issue, we propose a novel conceptual design of an electrostatic clutch that employs cylindrical electrodes. The aim of this study is to maintain a consistent friction force range by ensuring a constant overlapping area. In demonstrating the proof of concept, we delineate the design specifications for a clutch that is customized for a haptic force feedback glove. The clutch is characterized by its compact length, lightweight construction, and cost-effectiveness. Furthermore, this proposed clutch was designed with the specific intention of providing tactile force feedback by holding the fingers of users and addressing challenges related to wearability. An experiment was conducted to determine the minimum force required to perceive resistance on the finger, showcasing the clutch’s suitability for use in VR gloves. The results revealed that the average force exerted was measured at 2.8 N. The proposed clutch demonstrates the ability to hold a maximum force of 3 N at 1000 input voltage, which should maintain the allowable move length with a fixed force range. Additionally, the response time of the proposed clutch is documented to be less than 270 ms.