Integrated Resistive Sensor on Peano-HASEL Actuator for High-Speed Monitoring ; Integrierter Resistiver Sensor auf Peano-HASEL Aktuator für Hochgeschwindigkeitsüberwachung

As our society advances towards automation, soft robotic devices come to the fore. Unlike conventional machines made of rigid body parts, soft robots mimic the adaptability of natural organisms and represent safe candidates for medical applications, which depend on human machine interactions. In the past few years, a myriad of soft actuators has been developed with the aim of matching the excellence of biological muscles. Among them a promising new class of electrohydraulic actuators, called Peano-HASEL actuator has emerged, that demonstrates muscle-like strains and force outputs, yet high energy densities combined with self-sensing capabilities. However, the latter ability is limited to operation frequencies below 1 Hz as phase lag causes discrepancy between the real and the sensed displacement of the soft artificial muscle at higher frequencies. Here, I present an alternative method of sensing the Peano-HASEL actuators movement via an integrated resistive copper strain gauge. First, I established a theoretical model for describing the relevant strains affecting the sensor and determined its gauge factor of 2.59 ± 0.07 in characterization experiments. By incorporating the gauges manufacture into the actuators existing production processes I kept additional fabrication steps and costs to a minimum. A small sized signal processing unit allows for in-situ data acquisition of the sensor output in real-time, demonstrating the feasibility of wireless data transfer and untethered closed-loop control. Results show good agreement between real and measured actuation displacement at frequencies up to 10 Hz for sinusoidal and up to 20 Hz for rectangular operation voltages. Furthermore, the strain gauge responds to external stimuli, like touch, providing multifunctionality to the actuator. By expanding its sensing capabilities, this work contributes to the study and optimization of the smart artificial muscle, paving the way for its utilization in autonomous soft devices. ; Durch das Voranschreiten unserer Gesellschaft ...