基于复合位姿的二维自校准研究

Research on 2D self-calibration based on hybrid position

自校准与校准相比,无需精度等级高于被校准对象的标准样板,能以较低的条件成本实现精密测量仪器系统误差的校准。二维自校准中的标准样板常采用初始、相对旋转和平移的传统三位姿组合。位姿之间相互独立且所有位姿变换均以初始位姿为基础。采用旋转和平移两种位姿复合后的位姿,能避免两次位姿变换之间必须将标准样板回归初始位姿的冗余操作,简化了二维自校准流程。基于复合位姿的二维自校准经仿真实验证明能在模拟噪声环境中有效分离被校准对象的误差,其不确定度与传统非复合位姿组合的相等。复合位姿的引入不影响二维自校准的噪声抑制能力。在影像测量仪上实施二维自校准实验,采用包含复合位姿的三位姿组合的二维自校准分离的工作台系统误差接近传统三位姿组合。两种位姿组合对应的工作台系统误差结果相差0.167μm。另外通过采用包含复合位姿的四位姿组合的实验结果,进一步论证了基于复合位姿的二维自校准效果。

Compared with calibration,the self-calibration does not require a standard artifact with higher precision level than that of the object to be calibrated,which can achieve the calibration of system errors of precision measuring instruments at a low cost of conditions.The standard artifact in 2 D self-calibration usually employs traditional three-positions combination of initial position,relative rotation and translation.The positions are independent of each other,and all position transformations are based on the initial position.The utilization of the hybrid position combined with rotation and translation can void the redundant operation of returning the standard artifact to initial position between two position transformations to simplify the process of 2 D self-calibration.The 2 D self-calibration based on hybrid position is proved by simulation experiments to be effective in separating the errors of the calibrated objects in the simulated noisy environment,and its uncertainty is equal to that of the traditional combination of non-hybrid positions.The introduction of hybrid position has no influence on the noise suppression capability of 2 D self-calibration.The 2 D self-calibration experiments are conducted on a vision measuring machine,and the stage system errors separated by the 2 D self-calibration using a three-positions combination including a hybrid position are close to that of traditional three-positions combination.The results of the stage system errors corresponding the two positions combinations differ by 0.167μm.In addition,the effect of two-dimensional self-calibration based on hybrid position is further demonstrated by experimental results using a four-positions combination including a hybrid position.