摘要
为了研究7轴关节式坐标测量机的测量模型及其标定技术,根据DH模型(Denavit-Hartenberg notation)对7轴关节式坐标测量机进行了建模,并对参数个数和含义进行了深入研究.通过仿真发现7轴关节式坐标测量机直接标定时不能有效辨识某些参数的特殊问题.为解决该问题,设计了弯杆测头对测量机的整机参数进行标定.最后,将测量机测头换回直杆测头进行测头校准,获得更换测头后的测头参数.实验表明该方法能够有效地辨识出测量机整机的参数,能有效保证测量机的精度,这也证明了给出的测量模型的正确性。
Based on D-H(Denavit-Hartenberg) notation,the measurement model and calibration technology for a seven-axis articulated arm coordinate measuring machine(AACMM) were researched.The number and definitions of kinematic model parameters were further studied.Simulation experiments revealed a special problem: some parameters can not be effectively identified by direct calibration.To solve the problem,a vertical rod was made and fitted into the probe to identify all parameters of the seven-axis AACMM.Finally,the probe was calibrated by placing the straight rod back and the probe parameters could be obtained.Not only can the experiments prove that the method presented can guarantee the precision of the AACMM with seven axes by identifying all parameters,but they can also verify the validity of the kinematic model.
基金
国家自然科学基金(51075117)资助
关键词
关节式坐标测量机
运动学模型
参数标定
articulated arm coordinate measuring machine(AACMM)
kinematic model
parameter identify