INVESTIGATION OF A HOMODYNE AND A HETERODYNE LASER INTERFEROMETER FOR DYNAMIC FORCE MEASUREMENT

摘要

Homodyne and heterodyne laser interferometers can be used for dynamic force calibration and for acceleration measurement with sinusoidal and with shock excitation. The characteristics of both types of interferometers in acceleration measurement are compared in this paper. The data acquisition system comprises a four channels ADC card and a digital multimeter to sample the interferometer and force transducer or accelerometer signals synchronously. The nonlinearity effects of homodyne and heterodyne interferometers in acceleration measurement are analyzed. A transducer is calibrated using both interferometers and good accordance is demonstrated.