Multi-motion mode implementation of a bipedal piezoelectric stick-slip actuator based on jellyfish bionics

An innovative piezoelectric stick-slip actuator is designed, which incorporates the simple motion mode of ‘contraction-relaxation’ of jellyfish umbrella body and the flexible motion advantage of symmetrical configuration. The actuator features a bionic jellyfish-inspired flexure hinge mechanism (BJFHM), which is consisted by a dual drive foot and a bridge-type mechanism. The deformation within the bridge-type mechanism is conveyed to the dual driving feet, allowing the two sliders to operate either independently or in conjunction. Thereby, enabling a greater variety of motion modes and enhancing operational efficiency. The pseudo-rigid body model and finite element analysis (FEA) are presented. Finally, the experimental results generated by the piezoelectric stick-slip actuator are demonstrated. At 350 Hz, the left-right locking force is 0.5–1.5 N, with velocity reaching 16.44of the left and 2.37 mm/s of the right. The resolutions achieved on the left and right are 51 and 56 nm, respectively. The improvements made with the proposed actuator are confirmed by the results.