NAVIGATION SYSTEM FOR AUTOMATIC GUIDED VEHICLE
 Inventors: Barry D. Douglas, Doylestown; Joseph A. Bencel, Quakertown, both of Pa.
 Assignee: FMC Corporation, Chicago, 111.
 Appl. No.: 08/795,267  Filed: Feb. 10, 1997
 Int. CI.7 G06F 165/00
 U.S. CI 701/23; 318/587; 180/168
 Field of Search 701/23, 24; 318/587;
180/167, 168, 169
 References Cited
U.S. PATENT DOCUMENTS
4,284,160 8/1981 Deliban et al 180/168
4,361,202 11/1982 Minovitch 180/168
4,530,056 7/1985 MacKinnon et al 364/424
4,716,530 12/1987 Ogawa et al 364/424
4,780,817 10/1988 Lofgren 364/424.01
4,791,570 12/1988 Sherman et al 364/436
4,990,841 2/1991 Elder 318/587
5,163,001 11/1992 Luke, Jr 364/424.02
5,187,664 2/1993 Yardley et al 364/424.02
5,267,173 11/1993 Tanizawa et al 364/478
Primary Examiner—Michael J. Zanelli
Attorney, Agent, or Firm—Pauley Petersen Kinne & Fejer
A method and system for navigating automatic guided vehicles (AGVs) through a workplace having intelligible areas provides multi-vehicle traffic control. A guidance apparatus conveys a plurality of guidance signals, and a plurality of radio frequency tags (RF tags) are provided along the path over which the vehicle travels. Each RF tag is capable of conveying at least one of a plurality of unique radio frequency signals in response to electromagnetic excitation fields. A controller mounts on the vehicles, and includes an AGV computer, a sensor, a radio frequency identification (RFID) reader, and an RF modem for broadcasting messages to other vehicles to facilitate multi-vehicle traffic control. RF tags positioned for identifying characteristic area conditions related to the path of the vehicle reduce the need for custom modifications to guidance software on the host or AGV computers when operating in new environments, e.g., a new factory floor layout. The controller is responsive to at least one of the plurality of guidance signals received by the sensor and at least one characteristic area condition identified by the RF tag reader coupled to the AGV computer for initiating a predetermined action for navigating the vehicle through the area.
22 Claims, 4 Drawing Sheets