Apparatus for measuring kinematic errors in power transmission mechanisms

摘要

An apparatus for measuring kinematic errors in power transmission mechanisms with an input shaft and an output shaft. The apparatus comprises a pair of laser doppler velocimeters (LDV's) (16,34). Each generates a laser beam split into two equal-intensity parallel beams which are projected so as to strike a shaft while the shaft rotates. The shaft produces reflected beams having a frequency which is shifted from that of the incident beams, thereby producing returning beams which are heterodyne. A measuring (20,38) channel is in communication with each LDV. An attenuator (24) is in communication with one of the measuring channels (20) for decreasing the amplitude of a signal generated by the measuring channel (20). A summing and integrating amplifier (28) is connected to the attenuator, the amplifier generating a signal indicative of kinematic error in the gear mechanism.