Inspection method and apparatus for determining the side-up orientation of an object resting on a flat surface

摘要

A method and apparatus which can reliably inspect three dimensional objects resting on a surface such that part type, part location, side-up orientation, and orientation about a vertical axis can be determined with a single camera. The object to be inspected is supported on a support member which may be a conveyor. The support member possesses two specific optical characteristics. First, the support member must permit direct viewing therethrough of the object supported thereon without any significant loss of clarity. The support member must also be capable of diffuse reflection of a portion of the light incident thereon. A camera is positioned below the support member and a light source is positioned above the support member to back-light the object for the camera. That portion of the light diffusely reflected off the support member serves to illuminate any downward-facing surfaces of the object which are not in contact with the support member. Surfaces of the object which are in contact with the support member are darker than downward-facing surfaces of the object which are not in contact with the support member. A computer evaluates the image.