Abstract: A positioning device employing a single image pick-up device whereby two objects can be accurately aligned irrespective of inaccuracies in the pick-up device. The positioning device includes as a primary element an optical device composed of two prisms joined at oblique surfaces with a half-silvered mirror surface therebetween. The objects to be aligned are positioned adjacent first side surfaces of corresponding ones of the two prisms. A totally reflecting coating is provided on a second side surface of one of the two prisms, and an image pick-up device, namely, a video camera, is disposed to receive light emanating from the parallel second side surface of the other one of the two prisms. Alignment is effected in accordance with the output signal from the video camera.

Abstract: An optically guided, unmanned, load transporting vehicle, such as a fork-lift truck, includes an electric camera, such as an industrial television camera, and a controller for controlling the automatic running apparatus of the vehicle. Two reflectors are disposed in front of the camera so that the camera receives light from remote and near visual fields. A guide belt laid on floor for guiding the vehicle is formed with various bar codes representing halt, acceleration, deceleration, etc.