Abstract The direction from which a bullet or other object came is ascertained by comparing the points at which the object passed spaced-apart planes. Spaced electrically conducting wires or strips are crisscrossed to form a grid. A passing object smashes through the grid of pairs of electrical wires or strips in a first plane. It forces one wire or strip of a first pair into contact with a second wire or strip to close an electrical circuit. The object also closes a circuit through a second pair of wires or strips, in the first plane, running at right angles to the first pair, to close a second electrical circuit. An indicator or computer senses the point at which the object passed through these two pairs of wires or strips in the first plane. A similar grid is placed in a second plane, substantially parallel with said first plane. The second grid is also pierced by the passing object. The indicator or computer senses the point at which the object passed the second plane. It compares the two points and determines the direction from which the object came.
Apparatus for determining movement characteristics of a passing object comprising a first crisscrossed grid pattern of spaced-apart sensing devices, a second crisscross grid pattern of spaced-apart sensing devices substantially parallel with said first grid but spaced therefrom, each sensing device comprising pairs of substantially parallel mesh conductors one another but not in electrical contact and adapted to be distorted into electrical contact with one another by the passing object, and indicator means electrically connected to said first and said second grids of mesh conductors to indicate the point where a passing object penetrated each grid whereby a comparison of the points indicates the direction of travel of the passing object.
Claim 2
Dependent Claim
110 words
Apparatus for determining movement characteristics of a passing object comprising a first crisscrossed grid pattern of spaced-apart sensing devices, a second crisscross grid pattern of spaced-apart sensing devices substantially parallel with said first grid but spaced therefrom, each sensing device comprising pairs of substantially parallel mesh conductors one another but not in electrical contact and adapted to be distorted into electrical contact with one another by the passing object, and indicator means electrically connected to said first and said second grids of mesh conductors to indicate the point where a passing object penetrated each grid whereby a comparison of the points indicates the direction of travel of the passing object.