Patent ID: 8146702

Claim:
A material handling device having an automated guided vehicle configured for use with a carrier comprising: a vehicle bumper, mounted to the automated guided vehicle, including a vehicle reflective target secured to said bumper; a sensor, mounted on the automated guided vehicle, having a light source capable of transmitting a first and a second light beam and a scanner for receiving a reflection from said first and said second light beam; said first light beam directed toward the vehicle reflective target; said vehicle reflective target being moveable in response to deflection of said vehicle bumper from a non-reflective position to a reflective position when said vehicle bumper is moved toward said sensor; a carrier bumper, mounted to the carrier, including a carrier reflective target secured to said carrier bumper; said second light beam directed to the carrier reflective target; said carrier reflective target being moveable in response to deflection of said carrier bumper from a non-reflective position to a reflective position when said carrier bumper is moved toward said sensor; and a controller for controlling the automated guided vehicle in response to a signal from said sensor.