基于压电陶瓷的并联六自由度平台的位姿控制模型与验证

Pose control model and verification of parallel 6-DOF platform based on piezoelectric ceramics

针对传统电机驱动的小型Stewart平台无法达到纳米级定位的问题,设计了一种基于压电陶瓷的并联六自由度平台。该平台采用球副连接、对称分布及单层结构的设计,起到提升小型Stewart平台的定位精度的目的。通过分析并联六自由度平台定位原理,构建了6个自由度的位姿控制模型。通过仿真软件进行有限元分析,同时,在实体样机上进行实验分析,验证位姿控制模型的正确性。分析结果显示:并联六自由度平台沿X、Y和Z方向的行程均为-13.48~13.99μm,沿U、V方向的行程均为-616.59~639.17μrad,沿W方向的行程为-406.02~391.68μrad。目标位移与实验结果的最大误差为3.71%,验证了位姿控制模型的正确性。

Aiming at the problem that the small Stewart platform driven by traditional motor cannot achieve nanometer positioning,a parallel six Degrees Of Freedom(6-DOF)platform by piezoelectric ceramics was designed.The platform adopts the design of spherical pair connection,symmetrical distribution and single layer structure to improve the positioning accuracy of small Stewart platform.By analyzing the positioning principle of parallel 6-DOF platform,a pose control model with six degrees of freedom was constructed.The finite element analysis was carried out by simulation software,and the experimental analysis was carried out on the solid prototype to verify the correctness of the pose control model.The analysis results show that the stroke of the parallel 6-DOF platform along the X,Y and Z directions is-13.48~13.99μm,the stroke along the U,V directions is-616.59~639.17μrad,and the stroke along the W direction is-406.02~391.68μrad.The maximum error between the target displacement and the experimental result is 3.71%,which verifies the correctness of the pose control model.