基于相对视觉位姿的Stewart平台运动学标定

Kinematic Calibration of Stewart Platform Based on Relative Visual Pose

为了提高飞行模拟器运动系统的控制精度,针对电动Stewart六自由度运动平台,利用测量相对位姿的方法进行运动学误差分析和标定。根据Stewart平台结构特点,提出回转误差及回转补偿算法。由并联机构运动学方程和矢量闭环特性,建立Stewart平台运动学误差模型及优化标定算法。采用基于容错编码技术的标记块设计方案提高测量系统的稳定性,利用Basler工业级摄像机实现对上平台位姿跟踪与测量,获取上平台相对位姿,根据标定模型及优化算法辨识系统结构误差参数并补偿。最终测量数据与实验结果验证了标定算法的有效性,提高了Stewart平台控制精度。

To improve the control accuracy of flight simulator motion system, a kinematic error analysis and calibration based on relative visual pose measurement of electric Six-DOF Stewart platform were proposed. Considering the structural characteristic of Stewart platform, a rotary compensation algorithm was concerned firstly to raise the control accuracy. Then kinematic error model and optimal calibration algorithm were established, according to kinematic equations and vector closed-loop characteristic. Latterly, pose data was achieved using Basler industrial camera and ID marker featured by CRC（Cyclic Redundancy Check） and FEC（Forward Error Correction）. Finally, measurements and experiment results supported the validity of the algorithm and higher control precision was obtained.