Related Experiment Video
Updated: Aug 23, 2026

Ocular Kinematics Measured by In Vitro Stimulation of the Cranial Nerves in the Turtle
Published on: June 2, 2018
Precision goniometer equipped with a 22-bit absolute rotary encoder
1Photon Factory, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba-shi 305, Japan.
Abstract:
The calibration of a compact precision goniometer equipped with a 22-bit absolute rotary encoder is presented. The goniometer is a modified Huber 410 goniometer: the diffraction angles can be coarsely generated by a stepping-motor-driven worm gear and precisely interpolated by a piezoactuator-driven tangent arm. The angular accuracy of the precision rotary stage was evaluated with an autocollimator. It was shown that the deviation from circularity of the rolling bearing utilized in the precision rotary stage restricts the angular positioning accuracy of the goniometer, and results in an angular accuracy ten times larger than the angular resolution of 0.01 arcsec. The 22-bit encoder was calibrated by an incremental rotary encoder. It became evident that the accuracy of the absolute encoder is approximately 18 bit due to systematic errors.
Related Concept Videos
Gyroscope
Gyroscope: Precession
Azimuths and Bearings
Torque Free Motion
Uncertainty in Measurement: Reading Instruments
Relative Motion Analysis using Rotating Axes
However, to express the relative position of point B relative to point A, an additional frame of reference, denoted as x'y', is necessary. This additional frame not only translates but also rotates relative to the fixed frame, making it instrumental in...
