This paper investigates the effect of a major overhaul on the positioning accuracy and repeatability of a KUKA KR6 R900 industrial robot. The robot has been used extensively for teaching and programming activities, during which occasional collisions and long-term mechanical wear may have affected its positioning performance. To assess the changes resulting from the overhaul, experimental measurements were carried out before and after the maintenance intervention under defined operating conditions, using a methodology based on ISO 9283. Positioning deviations and repeatability were evaluated at two operating speeds using a measurement system equipped with six contact displacement sensors. The results show how the robot's positioning performance changed after the overhaul and highlight the importance of verifying its technical condition before returning it to regular operation.
Science Journal 