An optoelectronic measurement system for measuring 6-degree-of-freedom motion error of rotary parts
Journal
Optics Express
Journal Volume
15
Journal Issue
22
Pages
14601-14617
Date Issued
2007
Author(s)
Abstract
This paper presents an optoelectronic measurement system for measuring 6 degree-of-freedom (DOF) motion error of rotary parts. It comprises a pyramid-polygon-mirror, three laser diodes and three 2-axis position sensing detectors (PSD). The laser/PSD pairs are arranged evenly around the pyramid-polygon-mirror, which is mounted rigidly on and aligned axially with the rotary part to be measured. Laser rays from the laser diodes are reflected off the respective mirrors to the respective PSDs. The incidence point of the laser ray on the PSD's surface varies with the pose of the pyramid-polygon-mirror, allowing the PSD to register variation in the mirror and, thereby, the rotary part. With appropriate orientation of the lasers and PSDs, this system can measure variation (error) during rotation of a rotary part. By use of skew-ray tracing and first order Taylor series expansion, the system achieves measurement of translational and rotational motion errors for each Cartesian axis. To validate the proposed methodology, a laboratory prototype system is built. System verification and stability tests are conducted to evaluate its performance. Stability test results show that measurement errors and maximum crosstalk are within ±1 μm in translation and ±1.5 arc sec in rotation. ? 2007 Optical Society of America.
Subjects
Crosstalk
Degrees of freedom (mechanics)
Measurement errors
Position measurement
Semiconductor lasers
Taylor series
Position sensing detectors (PSD)
Rotational motion errors
Stability tests
Optoelectronic devices
SDGs
Type
journal article