Romer (tool)

A Romer arm is a portable coordinate measuring machine (CMM) often used in manufacturing and quality control. It's a multi-jointed arm with rotary encoders that measure the angles of the joints. These angular measurements, combined with known lengths of the arm segments, are used to calculate the position of a probe located at the end of the arm in three-dimensional space.

Romer arms are typically employed for tasks such as inspection, reverse engineering, dimensional analysis, CAD comparison, and on-machine verification. Their portability allows them to be used directly on the shop floor, near the manufacturing process, rather than requiring parts to be moved to a dedicated CMM room. This can significantly reduce inspection time and improve production efficiency.

The accuracy of a Romer arm depends on several factors, including the arm's length, the number of joints, and the quality of the encoders. Regular calibration is essential to maintain accuracy.

Different models of Romer arms are available, offering varying ranges of motion, accuracy levels, and features such as integrated scanners for non-contact measurement. They are frequently used in industries such as automotive, aerospace, and manufacturing.