Supersonic projectile e.g. bullet speed and impact position measurement - using fixed pressure sensors to measure time and space characteristics of bow wave

摘要

The method uses fixed sensors (6,7) along the trajectory of a supersonic body (1), pref. a projectile, to measure the bow wave pressure at two points (6,7). The time lapse between the pressure variations at the sensors gives a measure of the body's speed. Similar measurements using additional sensors (12,13) not on the trajectory enable bow waves from other supersonic bodies to be distinguished. The impact point of the projectile on a plane target can be accurately determined by measuring the arrival times of the bow wave at three pressure sensors in a plane close to and fixed geometrically w.r.t. the target. USE/ADVANTAGE - In shooting practice or competition enables every bullet's performance to be characterised. Present optical methods measure only speed and use sacrificial sample whose behaviour may not correspond to that of all batch.