Electromechanical model for electro-ribbon actuators

Abstract

• An electromechanical model for the electro-ribbon actuators with large deflection is established. • The model is experimentally validated. • The influence of design parameters is studied to achieve the desired force-extension behaviour. • A pathway for optimising output force and specific energy is introduced. The emerging field of soft actuators is anticipated to significantly impact areas that require enhanced adaptability and safe interaction including biomedical robotics. The electro-ribbon actuator, characterised by its compliance, lightweight, high efficiency, extensive scalability, and direct electrical control, emerges as a promising candidate for the future of soft robotics. Although the electro-ribbon actuator demonstrates efficient performance, a comprehensive understanding of its fundamental mechanics remains unexplored. To explain the impact of the actuation mechanism and the design parameters on the performance of the actuator, we have developed a mathematical model grounded in large deformation beam theory. As evidenced by our experimental results, this model accurately predicts the quasi-static behaviour of electro-ribbon actuators. Utilising this model, we establish a strategic road map for the development of electro-ribbon actuators with a range of passive stiffness tailored to achieve required output forces and displacement. This study provides a pivotal foundation for the model-based control and design optimisation of electro-ribbon actuators.