Utilizing the Peltier effect for actuation of thermo-active soft robots

Abstract

The field of soft actuation methods in robotics is rapidly advancing and holds promise for physical interactions between humans and robots due to the adaptability of materials and compliant structures. Among these methods, thermally-responsive soft actuators are particularly unique, ensuring portability as they do not require stationary pumps, or high voltage sources, or remote magnetic field. However, since working principles of these actuators are based on Joule heating, the systems are inefficient and dramatically slow, especially due to their passive cooling process. This paper proposes using the Peltier effect as a reversible heating/cooling mechanism for thermo-active soft actuators to enable faster deformations, more efficient heat transfer, and active cooling. The proposed actuator is composed of a thin elastic membrane filled with phase-change fluid that can vaporize when heated to produce large deformations. This membrane is placed in a braided mesh to create a McKibben muscle that can lift 5N after 60 seconds of heating, and is further formed into a gripper capable of manipulating objects within the environment. The effectiveness of the proposed actuator is demonstrated, and its potential applications in various fields are discussed.

Design, analysis, and testing of a variable-stiffness soft grabbing robot coupling particle jamming and layer jamming

“…The driving modes are the core in research on soft robots, which mainly include fluid-based actuation [3], semi-active actuation based on the jamming mechanism [4], cable-pulled actuation [5], electroactive polymer actuation [6], and pneumatic actuation [7]. In recent years, other special driving modes have been proposed, such as combustion-based actuation [8], microfluidic actuation [9], thermal actuation [10], chemical actuation [11], resonance actuation by dielectric elastomers [12], acoustooptic actuation [13], and magnetic actuation [14], which are also widely used.…”