In order to investigate the mechanisms of both the air-breathing and the ablation modes of laser propulsion under laboratory conditions, a multi-use laser impulse pendulum (MULIP) is developed. The measurable impulse range is from 1.0*10^(-4) to 3.8*10^(-3) N.s. The experimental calibration data agree well with the theoretical calculated data. With MULIP, the ablation mode has been performed, in which a high power pulsed Nd:glass laser (λ= 1.06 μm, τ= 20 ns) and a gray PVC film sample are used. The experimental results show that the maximum momentum coupling coefficient C_(m) is 7.73*10^(-5) N/W, and the maximum specific impulse I_(sp) is 208.6 s.