Research on Precise Biomimetic Actuator Based on Inchworm Principle

To solve the contradiction between precision and moving range, a precise biomimetic actuator and its controlling means were presented in the paper. The actuator is driven by piezoelectric ceramics. Based on inchworm principle, the actuator can move quickly in a wide range. Also, the actuator can realize precision positioning by error compensation. The actuator is composed of two clamping claws and a stretchable body. Based on finite element analysis, the actuator was devised and fabricated. Experiments on movement performance and positioning precision were carried out. The experiment results show that under closed loop control, the actuator can provide stable stepping movement with the stroke of 1 mm, the positioning accuracy of 0.01 mum and the driving force of 14 N.