Hybrid processing method and apparatus, navigation system, program storage device and computer data signal embodied in carrier wave

• US 20020169554A1
• Filed: 05/06/2002
• Published: 11/14/2002
• Est. Priority Date: 05/08/2001
• Status: Active Grant

• Current Assignee: Pioneer Corporation
• Original Assignee: Pioneer Corporation
• Inventors: Suda, Hiroyuki
• Granted Patent: US 6,785,609 B2
• Time in Patent Office: Days
• US Class Current: 701/216
• CPC Class Codes: G01S 19/22 Multipath-related issues
• CPC Class Codes: G01S 19/40 Correcting position, velocity or attitude
• CPC Class Codes: G01S 19/49 whereby the further system is an inertial position system, e.g. loosely-coupled

Abstract

A hybrid processing apparatus outputs current position data, indicating a current position of a movable body, on the basis of self-contained positioning data from a self-contained positioning apparatus (10) and GPS measurement data from a GPS receiver (18). In the hybrid apparatus, a judging device (20) judges whether or not an estimated error of the self-contained positioning data is greater than a predetermined threshold value. A first calculation device (20) calculates the current position by combining the GPS measurement data with the self-contained positioning data or a second calculation device (20) calculates the current position without combining the GPS measurement data, depending upon a judgment result of the judging device.

Claims

1. A hybrid processing method of outputting current position data, which indicate a current position of a movable body on which a self-contained positioning device and a GPS device are mounted, on the basis of self-contained positioning data from the self-contained positioning device and GPS measurement data from the GPS device,

said method comprising:

a judgment process of judging whether or not an estimated error of the self-contained positioning data is greater than a predetermined threshold value;

a first calculation process of calculating the current position by combining the GPS measurement data with the self-contained positioning data if the estimated error is judged not greater than the predetermined threshold value;

a second calculation process of calculating the current position from the GPS measurement data without combining the GPS measurement data with the self-contained positioning data if the estimated error is judged greater than the predetermined threshold value; and

an output process of outputting the current position calculated by said first or second calculation process as the current position data which indicate the current position of the movable body.

2. A hybrid processing method according to claim 1, wherein estimated error data, which indicate the estimated error, are outputted from the self-contained positioning device and said judgment process performs the judgment on the basis of the estimated error data.

3. A hybrid processing method according to claim 1, further comprising an estimated error calculation process of calculating the estimated error on the basis of the self-contained positioning data.

4. A hybrid processing method according to claim 1,

wherein said first calculation process (i) calculates the n-th measurement position from the GPS measurement data outputted for the n-th time (n is a natural number) by the GPS device, (ii) estimates the n+1-th measurement position as an estimated position depending on the self-contained positioning data with using the n-th measurement position as a standard, (iii) calculates the n+1-th measurement position from the GPS measurement data outputted for the n+1-th time by the GPS device, and (iv) performs an error correction based on the estimated position with respect to the n+1-th measurement position, to thereby calculate the n+1-th corrected measurement position as the current position, and

said second calculation process (v) calculates the n-th measurement position from the GPS measurement data outputted for the n-th time by the GPS device, (vi) estimates the n+1-th measurement position as an estimated position depending on the GPS measurement data with using the n-th measurement position as a standard, (vii) calculates the n+1-th measurement position from the GPS measurement data outputted for the n+1-th time by the GPS device, and (viii) performs an error correction based on the estimated position with respect to the n+1-th measurement position, to thereby calculate the n+1-th corrected measurement position as the current position.

5. A hybrid processing method according to claim 1, wherein

said judgment process performs the judgment before elapsing a predetermined period from a time of switching on a power of the self-contained positioning device and does not perform the judgment after elapsing the predetermined period, and

if the judgment is not performed, the present position is calculated by the first calculation process.

6. A hybrid processing apparatus for outputting current position data, which indicate a current position of a movable body on which a self-contained positioning device and a GPS device are mounted, on the basis of self-contained positioning data from the self-contained positioning device and GPS measurement data from the GPS device,

said apparatus comprising:

a judgment device for judging whether or not an estimated error of the self-contained positioning data is greater than a predetermined threshold value;

a first calculation device for calculating the current position by combining the GPS measurement data with the self-contained positioning data if the estimated error is judged not greater than the predetermined threshold value;

a second calculation device for calculating the current position from the GPS measurement data without combining the GPS measurement data with the self-contained positioning data if the estimated error is judged greater than the predetermined threshold value; and

an output device for outputting the current position calculated by said first or said second calculation device as the current position data which indicate the current position of the movable body.

7. A hybrid processing apparatus according to claim 6, wherein estimated error data, which indicate the estimated error, are outputted from the self-contained positioning device and said judgment device performs the judgment on the basis of the estimated error data.

8. A hybrid processing apparatus according to claim 6, further comprising an estimated error calculation device for calculating the estimated error on the basis of the self-contained positioning data.

9. A hybrid processing apparatus according to claim 6,

wherein said first calculation device (i) calculates the n-th measurement position from the GPS measurement data outputted for the n-th time (n is a natural number) by the GPS device, (ii) estimates the n+1-th measurement position as an estimated position depending on the self-contained positioning data with using the n-th measurement position as a standard, (iii) calculates the n+1-th measurement position from the GPS measurement data outputted for the n+1-th time by the GPS device, and (iv) performs an error correction based on the estimated position with respect to the n+1-th measurement position, to thereby calculate the n+1-th corrected measurement position as the current position, and

said second calculation device (v) calculates the n-th measurement position from the GPS measurement data outputted for the n-th time by the GPS device, (vii) estimates the n+1-th measurement position as an estimated position depending on the GPS measurement data with using the n-th measurement position as a standard, (vii) calculates the n+1-th measurement position from the GPS measurement data outputted for the n+1-th time by the GPS device, and (viii) performs an error correction based on the estimated position with respect to the n+1-th measurement position, to thereby calculate the n+1-th corrected measurement position as the current position.

10. A hybrid processing apparatus according to claim 6, wherein said judgment device performs the judgment before elapsing a predetermined period from a time of switching on a power of the self-contained positioning device and does not perform the judgment after elapsing the predetermined period, and.

if the judgment is not performed, the present position is calculated by the first calculation device.

11. An on-vehicle navigation system comprising

(i) a hybrid processing apparatus for outputting current position data, which indicate a current position of a movable body on which a self-contained positioning device and a GPS device are mounted, on the basis of self-contained positioning data from the self-contained positioning device and GPS measurement data from the GPS device, said apparatus comprising:

a judgment device for judging whether or not an estimated error of the self-contained positioning data is greater than a predetermined threshold value;

a first calculation device for calculating the current position by combining the GPS measurement data with the self-contained positioning data if the estimated error is judged not greater than the predetermined threshold value;

a second calculation device for calculating the current position from the GPS measurement data without combining the GPS measurement data with the self-contained positioning data if the estimated error is judged greater than the predetermined threshold value; and

an output device for outputting the current position calculated in said first or second calculation device as the current position data which indicate the current position of the movable body,

(ii) the self-contained positioning device and the GPS device, and

(iii) a display device for displaying the current position data outputted from said output device on map data in a predetermined format.

12. A program storage device readable by a computer, tangibly embodying a program of instructions executable by the computer to perform method processes of outputting current position data which indicate a current position of a movable body, on which a self-contained positioning device and a GPS device are mounted, on the basis of self-contained positioning data from the self-contained positioning device and GPS measurement data from the GPS device,

said method processes comprising:

a judgment process of judging whether or not an estimated error of the self-contained positioning data is greater than a predetermined threshold value;

a first calculation process of calculating the current position by combining the GPS measurement data with the self-contained positioning data if the estimated error is judged not greater than the predetermined threshold value;

a second calculation process of calculating the current position from the GPS measurement data without combining the GPS measurement data with the self-contained positioning data if the estimated error is judged greater than the predetermined threshold value; and

an output process of outputting the current position calculated by said first or second calculation process as the current position data which indicate the current position of the movable body.

13. A computer data signal embodied in a carrier wave and representing a series of instructions which cause a computer to perform method processes of outputting current position data which indicate a current position of a movable body, on which a self-contained positioning device and a GPS device are mounted, on the basis of self-contained positioning data from the self-contained positioning device and GPS measurement data from the GPS device,

said method processes comprising:

a judgment process of judging whether or not an estimated error of the self-contained positioning data is greater than a predetermined threshold value;

a first calculation process of calculating the current position by combining the GPS measurement data with the self-contained positioning data if the estimated error is judged not greater than the predetermined threshold value;

a second calculation process of calculating the current position from the GPS measurement data without combining the GPS measurement data with the self-contained positioning data if the estimated error is judged greater than the predetermined threshold value; and

an output process of outputting the current position calculated by said first or second calculation process as the current position data which indicate the current position of the movable body.