To recover measurement quickly after robot collision in robotic online visual measurement system, two simple and feasible methods to recalibrate the tool center point (TCP) of robot quickly are proposed. When there is a robot collision in the industry field, only several measurements are performed by moving the robot, then the tool coordinate is recalibrated and the robot TCP is recovered accurately, which can effectively avert the complex work of re-teaching the robot's measurement trajectory. The tool coordinate and TCP of the robot are defined in this paper first, based on the structure parameters of the light plane in visual sensor. Then the reference sphere based tool coordinate calibration method and common point deviation based calibration method are presented respectively. Simulation experiment testifies that the two methods can recover the robot tool coordinate and TCP quickly, and meet the demand of recovery measurement after robot collision in robotic visual measurement system.
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