05155684 is referenced by 230 patents and cites 43 patents.

A vehicle primarily for unmanned operation is equipped with a video camera pointed up, and progressively records in an on-board computer memory the observed locations of points derived from overhead features such as pre-existing overhead lights in a building during a manually driven teaching mode trip along a desired course. On subsequent unmanned trips, the vehicle directs itself along the chosen course by again observing the overhead features, deriving points from them and comparing the locations of those points to the locations of the points that were recorded during the teaching mode trip. It then corrects its steering to bring the errors between the observed locations and the recorded locations to zero, thereby directing the vehicle to automatically follow the course that was followed during the teaching mode trip.

Title
Guiding an unmanned vehicle by reference to overhead features
Application Number
262281
Publication Number
5155684
Application Date
July 17, 1991
Publication Date
October 13, 1992
Inventor
Ernest L Hall
Cincinnati
OH, US
Cao Z Liang
Tianjin
CN
Steven A Burke
Champlin
MN, US
Agent
Kinzer Plyer Dorn McEachran & Jambor
Assignee
Tennant Company
MN, US
IPC
G06F 15/64
G01C 21/00
G06E 15/50
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