Patent ID: 6603563
Filing Date: 2003-08-05
Classification: G01B

Abstract:
Method of determining measurements of an object moving along a conveyor path having a support surface, comprising:(a) projecting a light beam having a sharp edge from a light source aimed at a fixed angle of incidence transversely across the support surface to define a light beam intersect path; (b) moving the object along the support surface; (c) sensing a leading edge of the object at a fixed point along the conveyor path with a first sensor and generating a leading edge signal; (d) detecting the speed of the object with an object speed detector and generating an object speed signal; (e) detecting an initial blockage of the light beam intersect path on the support surface by the object and generating a height timing signal; (f) observing a reflected image of the light beam intersect path projected on the support surface in areas not obstructed by the object as the object moves along the support surface with an image sensor having a line of sight generally normal to the object support surface and generating a negative image profile signal; (g) transmitting the leading edge signal, the object speed signal, the height determination signal, and the negative image profile signal to a processor; and (h) calculating the object dimensions in the processor using the signals received from step (g), wherein a height of the object at the object leading edge is calculated in the processor by the formula: h=[xâˆ’v(tBâˆ’tLE)]tan a â€ƒwhere x=a fixed distance between the first sensor and the point of incidence of the sharp edge of light on the support surface, v=a speed of the object on the support surface determined by the speed signal, tB=the height timing signal, tLE=the leading edge, timing signal, and a=the angle of incidence of the at least one sharp edge of light from the light source.