Deterministic errors in pointing and tracking systems II: identification and correction of dynamic errors

摘要

Abstract: A precision tracking system can function in some applications with very limited absolute accuracy, but all applications require smooth motion. This paper addresses the sources of dynamic motion error which are built into the device itself. The methods of measuring these errors are discussed, and techniques for identifying the various sources. These are illustrated with some examples from precision tracking mounts. An important error source is motor torque ripple, a position-dependant variation in torque gain constant. New techniques in brushless servo motor excitation have resulted in dramatic reductions in torque ripple. An overview of this type of drive system is also presented.!