Abstract: A navigation system for use in a self guided material handling vehicle provides guidance during operation in areas having densely stacked rows of containers and reduces the potential of deviation of the self guided vehicle from the desired path of travel. A laser signaling device is mounted on the vehicle and rotatable about an axis of rotation extending generally perpendicularly to the longitudinal axis of the self guided vehicle. The laser signaling device is adapted to delivery a light beam signal at a first preselected angle relative to the axis of rotation and a directing device is provided for directing the delivered light beam signal, during a preselected portion of rotation of the laser signaling device, at a second different preselected angle relative to the axis of rotation. A receiving device receives a reflection of the light beam signal and delivers a position signal in response to the light beam signal received.