Azimuth processing device, azimuth processing method, azimuth processing program, direction finding device, tilt offset correcting method, azimuth measuring method, compass sensor unit, and portable electronic device

• US 8,090,535 B2
• Filed: 08/27/2010
• Issued: 01/03/2012
• Est. Priority Date: 07/23/2004
• Status: Expired due to Fees

• Current Assignee: Yamaha Corporation
• Original Assignee: Yamaha Corporation
• Inventors: Sato, Hideki, Yamaki, Kiyoshi, Omura, Masayoshi, Osuga, Chihiro, Nihashi, Satoshi, Mabuchi, Tetsuya
• Primary Examiner(s): Tran, Khoi
• Assistant Examiner(s): Peche, Jorge
• Application Number:
  US12/870,726
• Publication Number:
  US 20100324862A1
• Time in Patent Office: 494 Days
• Field of Search: 701/224, 701/220, 701/225, 702/150, 342/140, 731/78.R
• US Class Current: 701/224
• CPC Class Codes: G01C 17/38 Testing, calibrating, or compensating of compasses

Abstract

An azimuth processing device is designed for outputting azimuth data based on measurement data sequentially output from a compass sensor. In the device, an accumulation section selectively accumulates substantially new pieces of the measurement data. An offset data updating section updates offset data of the compass sensor based on plural pieces of the measurement data accumulated by said accumulation section. An azimuth data output section outputs the azimuth data based on substantially newest measurement data and the offset data.

Claims

1. An azimuth processing device for outputting azimuth data based on measurement data sequentially output from a compass sensor, the device comprising:

an accumulation section that selectively accumulates substantially new pieces of the measurement data;

an offset data calculating section that calculates an offset data candidate of the compass sensor based on plural pieces of the measurement data accumulated by the accumulation section; and

an offset data updating section that updates offset data stored in a memory with the offset data candidate calculated by the offset data calculating section,

wherein a compass space defined for the compass sensor is divided into a plurality of segments, wherein the memory includes an array having array elements corresponding to the segments of the compass space, and wherein the accumulation section accumulates a plurality of the substantially new measurement data for respective segments of the compass space in the array elements, thereby updating the measurement data of respective segments.

2. The azimuth processing device according to claim 1 further comprising an azimuth data output section that outputs the azimuth data based on substantially newest measurement data and the offset data.

3. The azimuth processing device according to claim 1, wherein the accumulation section compares the substantially newest measurement data with last accumulated measurement data, and selectively accumulates the substantially newest measurement data according to the comparison result.

4. The azimuth processing device according to claim 3, wherein the accumulation section selectively accumulates the substantially newest measurement data according to a distance between a position of the substantially newest measurement data in the compass space defined for the compass sensor and another position of the last accumulated measurement data in the compass space.

5. The azimuth processing device according to claim 1, wherein the offset updating section updates the offset data stored in the memory with the offset data candidate from the offset calculating section when variations in distances between positions of the accumulated plural pieces of the measurement data in the compass space and a position of the offset data candidate in the compass space meet predetermined criteria, and when the variations do not meet the predetermined criteria, the accumulation section deletes at least part of the accumulated measurement data, and the offset data is not updated by the offset data candidate.

6. An azimuth processing device for outputting azimuth data based on measurement data sequentially output from a compass sensor, comprising:

a first accumulation section that accumulates a predetermined number of the measurement data;

an offset data calculating section that calculates an offset data candidate of the compass sensor based on the accumulated measurement data after the predetermined number of the measurement data was accumulated by the first accumulation section;

a second accumulation section that accumulates new measurement data for a plurality of segments of a compass space defined for the compass sensor, wherein the new measurement data is stored in an array in a memory having array elements corresponding to the segments of the compass space, whereby the second accumulation section updates the measurement data of respective segments of the compass space after the offset data candidate has been calculated; and

an offset data updating section that updates offset data stored in the memory, based on the measurement data accumulated by the second accumulation section after the offset data candidate has been calculated.

7. The azimuth processing device according to claim 6 further comprising an azimuth data output section that outputs the azimuth data based on substantially newest measurement data and the updated offset data.

8. The azimuth processing device according to claim 6, wherein when variations in distances between positions of plural pieces of the measurement data in the compass space accumulated by the second accumulation section and a position of the offset data candidate do not meet predetermined criteria, the second accumulation section deletes at least part of the measurement data accumulated by the second accumulation section.

9. The azimuth processing device according to claim 8, wherein when variations in distances between positions of plural pieces of the measurement data in the compass space accumulated by the first accumulation section and a position of the offset data candidate in the compass space calculated based on the measurement data accumulated by the first accumulation section do not meet predetermined criteria, the first accumulation section deletes at least part of the accumulated measurement data, and the offset data is not updated by the offset data candidate.

10. The azimuth processing device according to claim 6, wherein when variations in positions of plural pieces of the measurement data in the compass space accumulated by the first accumulation section do not meet predetermined criteria, the first accumulation section deletes at least part of the accumulated measurement data.

11. The azimuth processing device according to claim 6, wherein when variations in positions of plural pieces of the measurement data in the compass space accumulated by the second accumulation section do not meet predetermined criteria, the second accumulation section deletes at least part of the measurement data accumulated by the second accumulation section.

12. The azimuth processing device according to claim 6 further comprising a reset section that allows the first accumulation section to reaccumulate the measurement data until the offset data calculating section recalculates a new offset data candidate when a distance between a position of the substantially newest measurement data in the compass space and a position of the offset data candidate in the compass space exceeds a reference value.

13. An azimuth processing method for outputting azimuth data based on measurement data sequentially output from a compass sensor, comprising the acts of:

selectively accumulating substantially new pieces of the measurement data;

calculating an offset data candidate of the compass sensor based on plural pieces of the measurement data accumulated by the accumulating act; and

updating offset data stored in a memory with the calculated offset data candidate,

wherein a compass space defined for the compass sensor is divided into a plurality of segments, wherein the memory includes an array having array elements corresponding to the segments of the compass space, and wherein the accumulation act accumulates a plurality of the substantially new measurement data for respective segments of the compass space in the array elements, thereby updating the measurement data of respective segments.

14. An azimuth processing program for outputting azimuth data based on measurement data sequentially output from a compass sensor, the program allowing a computer to perform the acts of:

selectively accumulating substantially new pieces of the measurement data;

calculating an offset data candidate of the compass sensor based on plural pieces of the measurement data accumulated by the accumulating act; and

updating offset data stored in a memory with the calculated offset data candidate, wherein a compass space defined for the compass sensor is divided into a plurality of segments, wherein the memory includes an array having array elements corresponding to the segments of the compass space, and wherein the accumulating act accumulates a plurality of the substantially new measurement data for respective segments of the compass space in the array elements, thereby updating the measurement data of respective segments.

15. A direction finding device comprising:

a compass sensor sequentially outputting measurement data;

an accumulation section that selectively accumulates substantially new pieces of the measurement data;

an offset data calculating section that calculates an offset data candidate of the compass sensor based on plural pieces of the measurement data accumulated by the accumulation section;

an offset data updating section that updates offset data stored in a memory with the offset data candidate calculated by the offset data calculating section, and

an azimuth data output section that outputs the azimuth data based on the substantially newest measurement data and the updated offset data,

wherein a compass space defined for the compass sensor is divided into a plurality of segments, wherein the memory includes an array having array elements corresponding to the segments of the compass space, and wherein the accumulation section accumulates a plurality of the substantially new measurement data for respective segments of the compass space in the array elements, thereby updating the measurement data of respective segments.

16. A portable electronic device comprising:

a screen;

a compass sensor sequentially outputting measurement data;

an accumulation section that selectively accumulates substantially new pieces of the measurement data;

an offset data calculating section that calculates an offset data candidate of the compass sensor based on plural pieces of the measurement data accumulated by the accumulation section;

an offset data updating section that updates offset data stored in a memory with the offset data candidate calculated by the offset data calculating section;

an azimuth data output section that outputs azimuth data based on the substantially newest measurement data and the updated offset data; and

a display control section that displays geographic information on the screen based on the azimuth data,

wherein a compass space defined for the compass sensor is divided into a plurality of segments, wherein the memory includes an array having array elements corresponding to the segments of the compass space, and wherein the accumulation section accumulates a plurality of the substantially new measurement data for respective segments of the compass space in the array elements, thereby updating the measurement data of respective segments.

17. An azimuth processing method for outputting azimuth data based on measurement data sequentially output from a compass sensor, comprising:

a selective accumulation act of selectively accumulating a predetermined number of the measurement data;

an offset data creating act of creating offset data of the compass sensor based on the accumulated measurement data after the predetermined number of the measurement data was accumulated by the selective accumulation act;

a segment accumulation act of accumulating new measurement data for respective segments of a compass space defined for the compass sensor, wherein the new measurement data is stored in an array in a memory having array elements corresponding to the segments of the compass space, and wherein the accumulating act updates the measurement data in a First In First Out (FIFO) manner for respective segments of the compass space in the array elements after creation of the offset data;

an offset data updating act of updating the created offset data based on the measurement data accumulated by the segment accumulation act after creation of the offset data; and

an azimuth data outputting act of outputting the azimuth data based on substantially newest measurement data and the updated offset data.

18. An azimuth processing program for outputting azimuth data based on measurement data sequentially output from a compass sensor, the program allowing a computer to perform the acts of:

a first accumulation act of accumulating a predetermined number of the measurement data;

an offset data calculating act of calculating an offset data candidate of the compass sensor based on the accumulated measurement data after the predetermined number of the measurement data were accumulated by the first accumulation act;

a second accumulation act of accumulating new measurement data for a plurality of segments of a compass space defined for the compass sensor, wherein the new measurement data is stored in an array in a memory having array elements corresponding to the segments of the compass space, wherein the second accumulation act updates the measurement data in a First In First Out (FIFO) manner for respective segments of the compass space in the array elements after the offset data candidate has been calculated;

an offset data updating act of updating offset data stored in the memory after the offset data candidate has been calculated; and

an azimuth data output act of outputting the azimuth data based on substantially newest measurement data and the updated offset data.

19. A direction finding device comprising:

a compass sensor sequentially outputting measurement data;

a first accumulation section that accumulates a predetermined number of the measurement data;

an offset data calculating section that calculates an offset data candidate of the compass sensor based on the accumulated measurement data after the predetermined number of the measurement data were accumulated by the first accumulation section;

a second accumulation section that accumulates new measurement data for a plurality of segments of a compass space defined for the compass sensor, wherein the new measurement data is stored in an array in a memory having array elements corresponding to the segments of the compass space, wherein the second accumulation section updates the measurement data in a First In First Out (FIFO) manner for respective segments of the compass space in the array elements after the offset data candidate has been calculated;

an offset data updating section that updates offset data stored in the memory based on the measurement data accumulated by the second accumulation section after the offset data candidate has been calculated; and

an azimuth data output section that outputs azimuth data based on substantially newest measurement data and the updated offset data.

20. A portable electronic device comprising:

a screen;

a compass sensor sequentially outputting measurement data;

a first accumulation section that accumulates a predetermined number of the measurement data;

an offset data calculating section that calculates an offset data candidate of the compass sensor based on the accumulated measurement data after the predetermined number of the measurement data were accumulated by the first accumulation section;

a second accumulation section that accumulates new measurement data for a plurality of segments of a compass space defined for the compass sensor, wherein the new measurement data is stored in an array in a memory having array elements corresponding to the segments of the compass space, wherein the second accumulation section updates the measurement data in a First In First Out (FIFO) manner for respective segments of the compass space in the array elements after the offset data candidate has been calculated;

an offset data updating section that updates offset data stored in the memory based on the measurement data accumulated by the second accumulation section after the offset data candidate has been calculated;

an azimuth data output section that outputs azimuth data based on substantially newest measurement data and the updated offset data; and

a display control section that displays azimuth information on the screen based on the azimuth data.