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Helping Robots Stay on Target



Elena R. Messina, Jeremy Marvel


For decades, many manufacturers have counted on robots to tirelessly produce parts of predictable quality. One of the key attributes of robots is their repeatability, which means that their tool tip will return to the same pre-programmed location with a relatively small error. This repeatability capability plays a role in ensuring predictability so that production proceeds smoothly and the downstream processes receive parts meeting the required tolerances. Repeatability is distinct from accuracy. A robot may position its end of arm tool (EOAT) at the same location with minimal errors (repeatability), but that location may not be where it should be in (accuracy). Both accuracy and repeatability are key performance characteristics that influence the robot's ability to meet a manufacturing process's needs. Generally, a robot's repeatability and accuracy are not achieved without upfront preparations and periodic maintenance. As robots evolve to become more affordable and applicable by a greater number of manufacturers, more enterprises are faced with having to educate themselves with what can be an esoteric set of concepts. In this article, we discuss some factors for manufacturers to consider and possible tools that may help.
Quality Magazine


collaborative robots, calibration, registration


Messina, E. and Marvel, J. (2019), Helping Robots Stay on Target, Quality Magazine (Accessed April 19, 2024)
Created December 2, 2019, Updated December 5, 2022