Design and simulation of a 2-DOF inchworm linear piezoelectric actuator

To meet the precise positioning in the plane, a 2-DOF linear inchworm actuator is designed. The bionic inchworm actuator used in this paper overcomes the shortcoming of the short stroke of the ordinary piezoelectric actuator and has the characteristics of no electromagnetic interference, power-off self-locking, and fast response. An inchworm actuator usually needs two clamping modules and one driving module to realize its basic function. When it needs to realize multi-degree-of-freedom motion, the number of modules is usually 3 times the freedom, which leads to high control cost and complexity. Therefore, in this paper, the inchworm actuator adopts a complementary design idea, which reduces the control complexity by directly reducing the number of modules while realizing the basic requirements of in-plane displacement. In this paper, the finite element analysis method is used to simulate and test several groups of flexible hinge displacement amplification mechanisms, and the appropriate magnification is selected. On this basis, the following results are obtained by simulation: the magnification of the displacement amplification mechanism to the output displacement of the piezoelectric ceramic stack is 6.0; when the input force is 250 N, the actuator load can reach 20 N.