Vehicle guidance system

A navigation system for a self guided vehicle, having a frame, and a longitudinal axis, and being supportable on an underlying surface, comprising:

• a laser signaling device mounted on the vehicle frame at a preselected elevational position and rotatable about an axis of rotation extending generally perpendicularly to said longitudinal axis, said laser signaling device being adapted to deliver a light beam signal at a first preselected angle relative to said axis of rotation during each revolution of the laser signaling device about said axis;
• means for directing the delivered light beam signal, during a preselected portion of each revolution of the laser signaling device, at a second different preselected angle relative to said axis of rotation, said directing means including a reflecting member having a preselected length and being fixedly mounted on the frame at a preselected location radially spaced from the axis of rotation of said laser signaling device and at a preselected angle relative to the axis of rotation lying in a plane of the axis of rotation passing through said reflecting member, said reflecting member lying in the path of the light beam signal at the first preselected angle and said preselected length establishing the angular magnitude of the preselected portion of rotation at which said light beam is delivered at said second preselected angle;
• a plurality of first targets positioned at preselected spaced apart locations and at substantially equal elevational distances from the underlying surface, said first targets being adapted to deliver a reflection of the light beam signal delivered at said first preselected angle;
• a plurality of second targets positioned at preselected spaced apart locations and at substantially equal elevational distances from the underlying surface, said second targets being spaced both elevationally and transversely from the first targets and adapted to deliver a reflection of the light beam signal directed at said second angle;
• means for receiving said reflections of the light beam signals delivered at said first and second angles and delivering a position signal in response to receiving any one of said light beam reflections;
• and
• computer means for receiving said position signal and correcting the direction of travel of said self guided vehicle in response to preprogrammed instructions.

An automatic storage/retrieval system having a self guided vehicle and at least two spaced apart rows of densely stacked containers defining an aisle therebetween, said self guided vehicle having a frame, a longitudinal axis, and a load carrying apparatus mounted on the frame and adapted to elevationally move selected ones of said containers, said self guided vehicle being supported on and moveable along an underlying surface, comprising:

• a laser signaling device mounted on the vehicle frame and rotatable about an axis of rotation extending generally perpendicularly to said longitudinal axis, said laser signaling device being adapted to deliver a light beam signal at a first preselected angle relative to said axis of rotation and at a first preselected minimum vertical distance from said underlying surface during each revolution of the laser signaling device about said axis;
• means for directing the delivered light beam signal, during a preselected portion of each revolution of the laser signaling device, at a second different preselected angle relative to said axis of rotation, said directing means including a reflecting member having a preselected length and being fixedly mounted on the frame at a preselected location radially spaced from the axis of rotation of said laser signaling device and at a preselected angle relative to the axis of rotation lying in a plane of the axis of rotation passing through said reflecting member, said reflecting member lying in the path of the light beam signal at the first preselected angle and said preselected length establishing the angular magnitude of the preselected portion of rotation at which said light beam is delivered at said second preselected angle;
• a plurality of first targets positioned at preselected spaced apart locations and at a second preselected vertical distance from the underlying surface, said first targets being adapted to deliver a reflection of the light beam signal delivered at said first preselected angle;
• a plurality of second targets positioned at preselected spaced apart locations and at a third preselected vertical distance from the underlying surface, said third vertical distance being greater in magnitude than the first and second vertical distances and said second targets being spaced from said first targets, said second targets being adapted to deliver a reflection of the light beam signal directed at said second angle;
• means for receiving said reflections of the light beam signals delivered at said first and second angles and delivering a position signal in response to receiving one of said reflections;
• and
• means for receiving said position signal and controlling navigation of said self guided vehicle in response to preprogrammed instructions.