The Study On Projectile Spin Rate Measurement For Small Arms

This paper presents a method for extraction of projectile spin information from Doppler radar measurements in order to meet the need of projectile spin rate measurements for small arms in the coming years. This method requires a series of parallel notches milled in the base of the projectile. This paper discusses emphasized the following aspects: the method of making slots in the base of projectile, projectile RCS calculation and its affect on the spin rate measurement, aerodynamic stability of the projectile, the way to get the spin signal and the measurement accuracy. The results of the research make it clear that, if the slots are made properly, the projectile can keep its aerodynamic stability and its ballistic characters. Thus it proves the feasibility to apply this method in the spin rate test of small arms. The spectrum analysis method is used to process Doppler signal. By using the classic spectrum estimation theory and data smoothing technique, the spin rate of projectile can be extracted from Doppler signal. Finally our real fire tests show that this method is simple and reliable, it is a new way to measure the projectile spin rate for small arms.