多关节柔性测量臂的关节零位偏差是由于装配引起的系统误差,对测量精度的影响极大.采取高精度的标定方法,获得关节零位偏差的实际值,然后对关节转角的理论值进行补偿,可以提高测量精度.首先应用D—H建模方法,建立了六自由度柔性测量臂的测量模型,在测量模型的基础上,应用全微分法建立了基于关节零位偏差的误差模型,然后用最小二乘法和迭代算法,建立了柔性臂关节零位偏差的线性标定方法,最后通过Matlab仿真验证了该标定算法的正确性.
The joint zero-position deviations of multi-joint coordinate measuring arm resulting from assembly technology errors, have an enormous influence on measuring accuracy. The actual joint zero-position deviations, which will be used to compensate the theoretical joint angle, can be obtained by taking a high precision calibration method. Thus, the measuring accuracy can be improved. Firstly, the measuring model of 6 DOF flexible measuring arm is established, then on the basis of the measuring model, the error model based on the joint zero-position deviations is set up by applying total differential, and then a linear calibration method is obtained by applying least square and iterative algorithm. Finally, the correctness of the calibration method is validated by Matlab simulation.