A new measuring method of the projectile velocity using flash shadowgraph system

A new measuring method of the projectile velocity using flash shadow graph system has been studied. The authors suggest a new measuring system using specially designed molecular nitrogen (N₂ ) laser flash shadowgraphy to capture the bullet position in relation to the reference plane of sensors (screens) and employ flash signal from ultra-high speed light detector directly as the trigger signal for chronograph. It follows that the trigger uncertainty produced by screen can be avoided. The design scheme using charge-coupled device (CCD) solid image camera to take shadowgraph without normal procedure including developing, fixing etc. is described. Experiments have proved that the approach is feasible