• With top equipment and years of experience, Fraunhofer IPA gets to the root causes of inaccurate robot operation. • Source: Rainer Bez, Fraunhofer IPA Robots are almost always highly repeatable. • Absolute accuracy, on the other hand, often leaves something to be desired. • A team at the Fraunhofer Institute for Manufacturing Engineering and Automation IPA is uncovering the reasons for this and helping companies to achieve more efficient robot systems. • Repeatability and absolute accuracy are established parameters for assessing the quality and precision with which a robot performs a specific task. • If a robot performs a specific task many times with almost identical results, this demonstrates very good repeatability.

Article Summaries:

  • Fraunhofer Institute for Manufacturing Engineering and Automation (IPA) is investigating why industrial robots, though highly repeatable (≈0.1 mm), often fall short in absolute accuracy (0.5-1.5 mm). Poor absolute positioning hampers processes that require precise, non‑repetitive placement-such as welding, pick‑and‑place, painting, and drilling-leading to quality defects and rejections. It also complicates offline programming, forcing costly corrections and downtime. IPA identifies root causes across hardware (encoder quality, gear design, rigidity), software, and external factors, and develops solutions to align absolute accuracy with repeatability, thereby boosting productivity and expanding robot applicability.
  • Fraunhofer Institute for Manufacturing Engineering and Automation IPA is investigating why industrial robots, while highly repeatable (≈0.1 mm), often fall short in absolute accuracy (≈0.5-1.5 mm). Poor absolute positioning hampers processes that require precise spatial coordinates, such as welding, pick‑and‑place, painting, drilling, and offline programming. Inaccuracies lead to quality defects, rejections, and costly re‑teaching or correction steps, reducing overall productivity. The institute identifies hardware issues (encoder quality, gear design, rigidity), software glitches, and external factors as root causes, and offers diagnostic and calibration solutions to help companies achieve accuracy comparable to repeatability.

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