Design of a precise positioning stage actuated by a double-layer stick-slip actuator used for precise assembly. (July 2023) - Shi, Beichao
Highlights: A novel stick-slip actuator with double layer structure is proposed. A novel two driving feet cooperative actuating principle is developed. The motion speed and step displacement of forward/backward motion are consistent. The actuating part is decoupled from the clamping force adjusting part. The proposed stick-slip stage is used in tiny objects assembly system. Abstract: A novel friction-actuated precise positioning stage used in precise assembly is proposed in this paper. Double-layer structure is adopted to construct the flexible mechanism of the stick-slip actuator. The actuating part is decoupled from the clamping force adjusting part, which is convenient to adjust the clamping force. The load capacity can be improved and the fallback motion at every step can be reduced by adopting this structure. In addition, a coarse-fine switching motion mode based on the double-layer cooperative driving principle is proposed. The amplification ratio and input stiffness are analyzed based on compliance matrix method (MCM). And the key parameters of the driving flexible mechanism are optimized based on the theoretical analysis. Then, the characteristic tests and precise assembly experiments are carried out to evaluate the performance of the positioning stage. The results indicate that the maximum moving speed and the maximum axial load are 12.7 mm/s and 2.1 N, respectively. Finally, the results of the precise assembly experiments indicate that the stick-slip stage can adjust the position errors precisely.