Safety Analysis, Design and Evaluation of 2-DOF Parallel Lifting Actuator on Stereo Parking Robot

Stereo garage technology can effectively alleviate the problem of parking difficulties, but the safety problems of its actuators, via which the core of stereo parking function can be realized, seriously affect its promotion and further development. In this paper, a two degrees of freedom (2-DOF) parallel lifting actuator for a stereo parking robot is designed by researching the type synthesis of the mechanism based on the screw theory. The limb constrained triangle method, the flexibility of limb constrained triangle, and the failure probability are proposed to determine the final configuration of the parallel lifting actuator. Then, this paper completes the dimensional optimization of the parallel lifting actuator based on the multi-motion performance indexes and kinematic analysis, which improves the safety and stability of the actuator. Finally, this paper verifies the validity of the parallel lifting actuator by establishing a parallel lifting actuator verification model system. By verifying the dynamic characteristics of the model mobile platform under different load conditions, it is proven that the kinematic stability of the mobile platform decreases with the increase of load mass under load conditions. Additionally, through practical application experiment, it is proven that the parallel lifting mechanism can effectively alleviate the parking difficulty problem.