Abstract: An accurate and high-speed measurement of the vehicle wheel alignment is achieved by an optoelectronic, non-contact measurement system. This system includes photoelectric sensors for detecting the distance between a reference vertical plane and a tire side surface of each wheel, and a stepping motor for adjusting the position of the sensors to follow-up the displacement of the wheel in a direction parallel to the longitudinal axis of the vehicle. Operation of the stepping motor is controlled by a microcomputer on the basis of the updated distance data delivered from the sensor inputs. The microcomputer processes the input data to compute a toe-in or a camber of the wheel for the analog or digital display.