05281901 is referenced by 56 patents and cites 129 patents.

An automated guided vehicle (AGV) control system which is downward compatible with existing guidewire systems providing both guidewire navigation and communication and autonomous navigation and guidance and wireless communication between a central controller and each vehicle. Autonomous vehicle navigation comprises travel over paths marked by update markers which may be spaced well apart, such as fifty feet Redundant measurement capability comprising inputs from linear travel encoders from the vehicle's drive wheels, position measurements from the update markers, and bearing measurements from a novel angular rate sensing apparatus, in combination with the use of a Kalman filter, allows correction for navigation and guidance errors caused by such factors as angular rate sensor drift, wear, temperature changes, aging, and early miscalibration during vehicle operation. The control system comprises high frequency two-way data transmission and reception capability over the guidewires and via wireless communications The same data rates and message formats are used in both communications systems. Substantially the same communications electronics are used for the central controller and each vehicle. Novel navigation and guidance algorithms are used to select and calculate a non-linear path to each next vehicle waypoint when the vehicle is operating in the autonomous mode. The non-linear path comprises an initial direction equal to the heading of the vehicle as it enters the path and a waypoint heading defined as part of the message received from the central control system which plans and controls travel of each vehicle in the system.

Title
Downward compatible AGV system and methods
Application Number
7/621486
Publication Number
5281901
Application Date
December 3, 1990
Publication Date
January 25, 1994
Inventor
Herman P Schutten
Milwaukee
WI, US
Joseph Zuercher
Brookfield
WI, US
L Bruce Christensen
Kaysville
UT, US
Robert K Forman
Taylorsville
UT, US
Rick S Mottes
Roy
UT, US
Vaughn W Guest
Farmington
UT, US
Bryan A Bloomfield
Bountiful
UT, US
John A M Petersen
Bountiful
UT, US
Gary L Whatcott
Holladay
UT, US
James V Yardley
Centerville
UT, US
Agent
Lynn G Foster
Assignee
Eaton Kenway
UT, US
IPC
A01B 69/04
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