Position-tracing system

• US 20060187028A1
• Filed: 02/10/2005
• Published: 08/24/2006
• Est. Priority Date: 02/10/2005
• Status: Active Grant

• Current Assignee: PINC Solutions Incorporated
• Original Assignee: PINC Solutions Incorporated
• Inventors: Kiang, Meng-Hsiung, Gollu, Aleks
• Granted Patent: US 7,236,091 B2
• Time in Patent Office: Days
• US Class Current: 340/539.130
• CPC Class Codes: G01C 21/165 combined with non-inertial navigation instruments
• CPC Class Codes: G06Q 10/08 Logistics, e.g. warehousing, loading or distribution; Inventory or stock management
• CPC Class Codes: G08G 1/20 Monitoring the location of vehicles belonging to a group, e.g. fleet of vehicles, countable or determined number of vehicles

Abstract

A position-tracking system for tracking the position of an object is disclosed. According to various embodiments, the tracking system includes a tracking device that is connected to or otherwise affixed to the object to be tracked. The tracking device may include, among other things, an inertial sensor assembly, radio transceivers and a processor. The position tracking system may also include a host processing system that is in communication with the tracking device. The position tracking system may provide variable-resolution position information based on the environment in which the object is moving. In a “wide resolution” area, the system may compute a general position for the object based on a wireless telephone network Cell-ID/map correlation architecture. In a high-resolution area, greater position resolution may be realized from the combination of a wireless aiding system and inputs from the inertial sensors. In the high-resolution mode, the system may exploit distinct patterns of motion that can be identified as motion “signatures” that are characteristic of certain types of motion. Kinematic (or object movement) models may be constructed based on these motion signatures and the position tracking system may estimate the state of the object based on the kinematic model for the current mode of the object. Adaptive and cascaded Kalman filtering may be employed in the analysis to more accurately estimate the position and velocity of the object based on the motion pattern identified.

Claims

1. A position-tracking system for tracking the position of at least one mobile object comprising:

a position-tracking device associated with the at least one mobile object such that the position-tracking device moves with the mobile object, wherein the position-tracking device includes at least one inertial sensor;

a wireless aiding system associated with a first area; and

a host computer system in wireless communication with the position-tracking device,

wherein the system includes a high resolution operational mode and a wide area resolution operational mode, and wherein the system transitions between the high resolution operational mode to the wide area resolution operational mode when the mobile object moves between the first area, which requires high object location resolution, and a second area, which requires lesser object location resolution, and wherein the location of the at least one mobile object in the high resolution operational mode is determined based on at least a combination of input from the at least one inertial sensor and reference position signals from the wireless aiding system received by the position-tracking device.

2. The system of claim 1, wherein the wireless aiding system includes at least one reference position transmitter located in the first area that transmits a reference position signal for reception by the position-tracking device.

3. The system of claim 1, wherein the position-tracking device is connected to the at least one mobile object.

4. The system of claim 1, wherein the position-tracking device is connected to a piece of equipment used to move the at least one mobile object.

5. The system of claim 1, wherein the system is for determining the location of the at least one mobile object in the wide resolution operational mode based on cell-ID information received by the position-tracking device from a wireless telephone network.

6. The system of claim 1, wherein the location of the at least one mobile object is computed by the position-tracking device and wirelessly transmitted to the host computer system.

7. The system of claim 1, wherein the computation of the location of the at least one mobile object is distributed between the position-tracking device and the host computer system.

8. The system of claim 1, wherein the position-tracking device further includes a receiver for receiving a signal indicating that the at least one mobile object is moving between the first area and the second area, and wherein the position-tracking system transitions between the high resolution mode and the wide area resolution mode in response to the signal.

9. The system of claim 6, wherein the position-tracking device comprises:

a high resolution module for computing the location of the at least one mobile object when the position-tracking device is in the high resolution operational mode; and

a wide area resolution module for computing the location of the object when the position-tracking device is in the wide area resolution operational mode.

10. The system of claim 9, wherein the wide area resolution module is for computing the location of the at least one mobile object in the second operational mode based on cell-ID information received by the position-tracking device from a wireless telephone network.

11. A position-tracking system for tracking the position of at least one mobile object comprising:

a position-tracking device associated with the at least one mobile object such that the position-tracking device moves with the mobile object;

a wireless aiding system; and

a host computer system in wireless communication with the position-tracking device,

wherein the position-tracking device comprises;

at least one inertial sensor;

a receiver for receiving reference position signals from the wireless aiding system; and

a processor in communication with the at least one inertial sensor and the receiver for computing the location of the at least one mobile object in real-time based on a combination of input from the at least one inertial sensor and reference position signals from the wireless aiding system.

12. The system of claim 111 wherein the processor is for computing the location of the at least one mobile object by:

detecting a current mode of movement for the at least one mobile object based on the input from the at least one inertial sensor and historical information about the location of the at least one mobile object;

determining a first estimated position of the at least one mobile object based at least on a motion model for the current mode of movement for the at least one mobile object;

determining a second estimated position of the at least one mobile object based on the input from the at least one inertial sensor and the historical information about the location of the at least one mobile object; and

estimating a real-time location of the at least one mobile object based on the first and second estimated positions.

13. The system of claim 12, wherein the processor is for estimating the real-time location of the at least one mobile object based on the first and second estimated positions using a Kalman filter.

14. The system of claim 12, wherein the processor further corrects the historical information about the location of the at least one mobile object based on corrective information.

15. The system of claim 14, wherein the corrective information includes a reference position signal transmitted by the wireless aiding system and received by the position-tracking device.

16. The system of claim 14, wherein the corrective information includes detection of a transition in the mode of movement by the at least one mobile object.

17. A method for tracking the position of at least one mobile object comprising:

associating a position-tracking device with the at least one mobile object such that the position-tracking device moves with the at least one mobile object, wherein the position-tracking device includes at least one inertial sensor;

detecting when the at least one mobile object moves between a first area, requiring high location resolution, and a second area, requiring lesser location resolution;

determining the location of the at least one mobile object when the mobile object is determined to be in the first area based on at least a combination of input from the at least one inertial sensor and reference position signals received by the position-tracking device from a wireless aiding system associated with the first area.

18. The method of claim 17, further comprising determining the location of the at least one mobile object when the at least one mobile object is determined to be in the second area based on at least cell-ID information received by the position-tracking device from a wireless telephone network.

19. The method of claim 17, wherein the step of determining the location of the at least one mobile object when the at least one mobile object is determined to be in the first area includes:

detecting a current mode of movement for the at least one mobile object based on the input from the at least one inertial sensor and historical information about the location of the at least one mobile object;

determining a first estimated position of the at least one mobile object based on at least a motion model for the current mode of movement for the at least one mobile object;

determining a second estimated position of the at least one mobile object based on at least the input from the at least one inertial sensor and the historical information about the location of the at least one mobile object; and

computing a real-time location of the at least one mobile object based on at least the first and second estimated positions.

20. The method of claim 19, wherein the step of computing the real-time location of the at least one mobile object based on the first and second estimated positions includes using a Kalman filter to compute the real-time location of the at least one mobile object based on the first and second estimated positions.