In this article, we present a sensorless stiffness control (SC) architecture for a soft dielectric elastomer (DE) membrane actuator. The method relies on a self-sensing algorithm that exploits measurements of electrical quantities (i.e., membrane voltage and current) to perform a real-time estimation of DE displacement and force. By combining self-sensing feedback with a SC algorithm, active shaping of the membrane force-displacement response is achieved without introducing additional electro-mechanical sensors in the system, thus, making it possible to design compact, lightweight, and low-cost DE robotic systems. A description of the novel self-sensing scheme is initially performed. To cope with the strong system nonlinearity, a robust design method to synthesize a SC law is subsequently proposed. An extensive experimental campaign is, then, carried out, with the goal of evaluating the performance of both sensor-based and sensorless SC. Quantitative accuracy of both control architectures is finally assessed and compared.
Towards Sensorless Soft Robotics: Self-Sensing Stiffness Control of Dielectric Elastomer Actuators / Rizzello, Gianluca; Serafino, Pietro; Naso, David; Seelecke, Stefan. - In: IEEE TRANSACTIONS ON ROBOTICS. - ISSN 1552-3098. - STAMPA. - 36:1(2020), pp. 8877754.174-8877754.188. [10.1109/TRO.2019.2944592]
Towards Sensorless Soft Robotics: Self-Sensing Stiffness Control of Dielectric Elastomer Actuators
Pietro Serafino;David Naso;
2020-01-01
Abstract
In this article, we present a sensorless stiffness control (SC) architecture for a soft dielectric elastomer (DE) membrane actuator. The method relies on a self-sensing algorithm that exploits measurements of electrical quantities (i.e., membrane voltage and current) to perform a real-time estimation of DE displacement and force. By combining self-sensing feedback with a SC algorithm, active shaping of the membrane force-displacement response is achieved without introducing additional electro-mechanical sensors in the system, thus, making it possible to design compact, lightweight, and low-cost DE robotic systems. A description of the novel self-sensing scheme is initially performed. To cope with the strong system nonlinearity, a robust design method to synthesize a SC law is subsequently proposed. An extensive experimental campaign is, then, carried out, with the goal of evaluating the performance of both sensor-based and sensorless SC. Quantitative accuracy of both control architectures is finally assessed and compared.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.