Firing range
AssigneeAustralasian Training Aids (Pty.) Ltd.
InventorsLindsay C. Knight, David A. Cash, Duncan Stewart, Robert A. Cottis, William H. Bowyer, Robert C. Newnham, Frederick J. Williams, David W. Pardon
Life of this patent
Estimating the term…
Abstract
An apparatus for use in a firing range, in which transducers located adjacent the target area detect the airborne shock wave from supersonic projectiles. The position at which each projectile passes through the target plane is determined from the relative time of arrival of the associated shock wave at the transducers. A visual display of the target and the projectile position is provided for the use of range personnel.
Claims21
Apparatus for determining the location in a predetermined two-dimensional target area adjacent a target member through which the trajectory of a projectile passes, said projectile originating from a firing point and directed toward said target member, the apparatus comprising:
- at least three transducers,
- means for positioning said at least three transducers in a generally horizontal elongate array adjacent an edge of the predetermined target area,
- said transducers positioned spaced apart one from the other at respective predetermined locations,
- each said transducer comprising means for providing an output signal in response to an airborne pressure wave generated by the projectile,
- individual threshold circuit means coupled to each transducer and responsive to said output signal for providing an indication signal when said output signal exceeds a predetermined threshold, the indication signal representing a time at which said airborne pressure wave generated by the projectile impinges on the transducer;
- and
- processing means, provided with data representing the respective predetermined locations at which the transducers are positioned and with data representing the speed of sound propagation in air, and operative for
- (1) predetermining time differences between the indication signal associated with one of said transducers relative to the indication signal associated with each of the remainder of the transducers;
- (2) calculating, from data representing the respective predetermined transducer locations, the speed of sound propagation in air, and said determined time differences, the location in said predetermined target area through which said trajectory passes, and
- (3) providing an indication of said calculated location.
Dependencies are inferred from the claim text.