Absolute calibration of an ABB IRB 1600 robot using a laser tracker

The absolute accuracy of an ABB IRB 1600 industrial robot is improved using a 29-parameter calibration model, developed after extensive experimentation. The error model takes into account all possible geometric errors (25 geometric error parameters to be identified through optimization, in addition to the pose parameters for the base and tool frames and four error parameters related to the compliance in joints 2, 3, 4 and 5). The least squares optimization technique is used to find the 29 error parameters that best fit the measures acquired with a laser tracker. Contrary to most other similar works, the validation of the robot's accuracy is performed with a very large number of measures (1,000) throughout the complete robot's joint space. After calibration, the meant maximum position errors at any of eight different measurement points on the end-effector (all offset from axis 6 by approximately 120 mm) are reduced from 0.968 mm/2.158 mm respectively, to 0.364 mm/0.696 mm. (c) 2012 Elsevier Ltd. All rights reserved.