Inline calibration method for robot supported process tasks with high accuracy requirements

Especially in cases of robot supported process tasks with high accuracy requirements, exactly known geometric relations of the process relevant cell components relative to each other is of significant importance. To establish these relations, several methods are known from the state of the art, belonging to the area of calibration. However, compensating all influencing factors individually can be very time consuming. Addressing this subject, a more straightforward inline calibration method has been developed in research activities at FAPS, compensating geometrical errors independent from their origin. Therefore, the central effect of inaccuracies is exploited, namely a geometrical misalignment of the process pattern relative to the workpieces. This misalignment is measured via an optical sensor system. Based on this information transformation relations are established and the robot control program subsequently modified in order to adapt the robot movement to the real geometrical relations. In conclusion, the impact of geometrical deviations is compensated. Experimental investigations show a significant improvement of the process result after applying the calibration method.