Development of a Four-Bar Linkage Integrated with a Polypyrrole Actuator and a Resistive Sensor Toward Biomimetic Pleopods

Abstract

Developing a highly integrated mesoscale (a few millimeter-centimeter) mechanism is dauntingly challenging work, and yet many technological improvements in soft robotics keep pushing the boundary. In this work, we proposed a new approach to develop a compliant mechanism integrated with a conductive polymer actuator and a resistive sensor. A polypyrrole (PPy) was utilized to fabricate a unimorph bending actuator through electropolymerization owing to its low operating voltage and high energy density. Also, carbon blacked filled polydimethylsiloxane (CPDMS) was directly contact printed on a flexural joint of a compliant mechanism to sense its motion. The performance of a PPy actuator and CPDMS sensor were individually investigated, which would be valuable at followup studies. In addition, inspired by pleopods (i.e. swimming legs) of aquatic arthropods, a CPDMS sensor integrated four-bar-linkage driven by a PPy actuator was developed for future applications in mesoscale swimming robots. After immersing in an electrolyte solution, the PPy actuator successfully drove the linkage structure with 5 V while the CPDMS sensor was able to partially sense the motion.