Inchworm-Like Bionic Micro-Robot Drived By SMA

Micro-robot is an important branch of the micro electro-mechanical system (MEMS), and it is the higher-level typical representation of the MEMS. Developing micro-robot whose geometric dimensions is mm-level (or even smaller) has always been a hot spot in MEMS domains. Micro-actuator is an important executive machine, which is the core component of MEMS. Because of the shape memory effect (SME) and unique mechanical performance, adopting shape memory alloy (SMA) actuator is one of the ways for realization of micro-miniaturization of the robot.(1) In the foundation of profiting many other people's study results, the SME and the unique mechanical performance of SMA were expounded, and the working principles of all types of SMA actuator were expatiated. A bias two way SMA actuator was developed, and a four-legged bionic micro-robot who moves like an inchworm was designed in the foundation of the actuator.(2) The output force direction of the micro-driver was changed by using the movement of a four-linkage mechanism, and the different friction coefficient materials were deposited on the four-linkage and the rigidized foot, through both combined action, the friction self-locking of the micro-robot is realized, and the forward movement of the micro-robot is achieved.(3) The modeling was carried on with the three-dimensional software Pro/E, and the simulation were carried on to the micro-elasticity-beam with the finite element analysis software ANSYS. The suitable curve was selected, the parameters (curvature, thickness, generous ratio, section sizes and so on) were optimized, the output displacements changing along with different input forces were gained, and the distortion and the stress distribution of the micro elastic-beam were analyzed. (4) The response time and the restoration time of the SMA spring were obtained by transient analyze. The force simulating SMA whose output force changes timely was loaded, and the dynamic simulation to the simplified model of the micro-leg was carried out by the explicit nonlinear dynamic analysis program at last.