(54) HYBRID TRACKER
(75) Inventors: Saul Stokar, Raanana (IL); David Neustadter, Netania (IL)
(73) Assignee: Elbit Systems Ltd., Haifa (IL)
( * ) Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 86 days.
(21) Appl.No.: 11/413,936
(22) Filed: Apr. 27, 2006
Related U.S. Application Data
(63) Continuation of application No. 11/343,486, filed on Jan. 31, 2006, now abandoned.
(30) Foreign Application Priority Data
Mar. 24,2005 (IL) 167648
(51) Int. CI.
G01C 21/00 (2006.01)
G01C 9/00 (2006.01)
(52) U.S. CI 701/214; 701/207; 701/221;
702/153; 702/150; 702/85; 702/86; 702/92; 342/147; 342/448; 342/450; 342/451; 342/463
(58) Field of Classification Search 703/8,
703/2; 600/595; 701/13,207,214; 702/94, 702/151, 95, 141; 324/207.17 See application file for complete search history.
(56) References Cited
U.S. PATENT DOCUMENTS
3,868,565 A 2/1975 Kuipers
5,645,077 A 7/1997 Foxlin
5,812,257 A * 9/1998 Teitel et al 356/141.4
5,847,976 A * 12/1998 Lescourret 703/8
6,176,837 Bl * 1/2001 Foxlin 600/595
6,263,264 Bl* 7/2001 Herman et al 701/13
Apparatus for determining the position of a selected object relative to a moving reference frame, the apparatus including at least one reference frame transceiver assembly firmly attached to the moving reference frame, at least one object transceiver assembly firmly attached to the selected object, an inertial measurement unit firmly attached to the selected object, an inertial navigation system firmly attached to the moving reference frame, and a tracking processor coupled with the object transceiver assembly, with the inertial measurement unit and with the inertial navigation system, the object transceiver assembly communicating with the reference frame transceiver assembly using magnetic fields, the inertial measurement unit producing IMU inertial measurements of motion of the selected object with respect to an inertially fixed reference frame, the inertial navigation system producing INS inertial measurements of motion of the moving reference frame with respect to the inertially fixed reference frame, the tracking processor receiving electromagnetic measurements resulting from the magnetic communication between the reference frame transceiver assembly and the object transceiver assembly, the tracking processor determining the position of the selected object relative to the moving reference frame by using the IMU inertial measurements and the INS inertial measurements to optimize the electromagnetic measurements.
18 Claims, 7 Drawing Sheets