Positioning device and positioning method

• US 8,862,396 B2
• Filed: 06/17/2010
• Issued: 10/14/2014
• Est. Priority Date: 07/09/2009
• Status: Active Grant

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: Sambongi, Masao
• Primary Examiner(s): Jabr, Fadey
• Assistant Examiner(s): INGRAM, THOMAS P
• Application Number:
  US12/817,321
• Publication Number:
  US 20110010089A1
• Time in Patent Office: 1,580 Days
• Field of Search: 701/472, 701/480, 701/498, 701/500, 701/505
• US Class Current: 701/501
• CPC Class Codes: G01C 21/1654 with electromagnetic compass
• CPC Class Codes: G01C 21/28 with correlation of data from several navigational instruments

Abstract

A positioning device including a movement measuring unit for measuring a relative positional change and a passing position calculation control unit for continuing measurement of the positional change of the movement measuring unit during movement, being given position data of any first point at the first point on a moving route excluding a start point, and determining position data of a point which has been passed before arrival at the first point on the basis of the given position data of the first point and data of the positional change continuously measured by the movement measuring unit.

Claims

1. A positioning device comprising:

a movement measuring sensor for measuring a relative positional change, the relative positional change being independent of geographic location of the positioning device;

a GPS receiver configured to provide a present position information associated with geographic location of the positioning device;

a passing position calculation control unit configured to calculate a relative movement from the relative positional change measured by the movement measuring sensor; and

a processor configured to receive the present position information from the GPS receiver and to determine whether the present position information is measurable by the GPS receiver, wherein;

positioning is determined from the present position information provided by the GPS receiver in response to the processor determining the present position information is measurable by the GPS receiver, and

the relative movement is calculated by the passing position calculation control unit in response to the processor determining the present position information is not measurable by the GPS receiver, and

in response to the present position information being determined by the processor to be provided by the GPS receiver after a period of time of not providing the present position information by the GPS receiver, the processor determines revised position data of a point which has been passed and which has been determined from the relative movement independent of geographic location, the revised position data being determined on the basis of a difference between position data of a first geographic position point obtained by the processor in response to the GPS receiver providing the present position information after a period of time of not providing the present position information by the GPS receiver and a last geographic independent point determined by the movement measuring sensor.

2. The positioning device according to claim 1, further comprising a position calculating unit for accumulating data associated with the relative positional change measured by the movement measuring sensor into position data of a start point to calculate position data of points on the moving route, wherein the processor further comprises:

a temporary position data calculation control unit for giving temporary position data of the start point to the position calculating unit, and making the position calculating unit to calculate temporary position data of the points on the moving route;

a position data storing unit for storing the temporary position data of the points on the moving route obtained by the temporary position data calculation control unit; and

a position data correcting unit for shifting the temporary position data of the points on the moving route stored in the position data storing unit so that position data calculated at the first point by the position calculating unit is identical to the given position data of the first point.

3. The positioning device according to claim 1, wherein the processor further comprises:

a change data storing unit for storing data of the relative positional change measured by the movement measuring unit sensor during movement; and

a passing position calculating unit for successively subtracting the data of the relative positional change stored in the change data storing unit from the given position data of the first point, thereby obtaining position data of respective points which have been passed before arrival at the first point.

4. A positioning method for obtaining position data on a moving route comprising:

using a processor and at least one sensor to perform;

acquiring a measurement of a relative positional change that is independent of geographic location;

determining whether a present position associated with geographic location is measurable;

generating a set of position data from the measurement of relative positional change in response to determining the present position is not measurable;

a second determining of whether the present position is measurable;

acquiring a first present position associated with a geographic location in response to a determination that the present position is measurable by the second determining;

acquiring a second measurement of relative positional change; and

generating correction data for the position generated from the measurement of relative positional change from a difference in position data between the first present position and the second measurement of relative positional change.

5. The positioning method according to claim 4, further comprising acquiring a sequence of measurements of the relative positional change independent of geographic location and settling data of the relative positional change into position data of a start point and position data of points on the moving route;

employing temporary position data of the start point and calculating temporary position data of the points on the moving route;

storing the temporary position data of the points on the moving route; and

shifting the temporary position data of the stored points on the moving route by the difference in position data so that the position data of the start point and the points on the moving route acquired independent of geographic location are corrected for respective geographic locations.

6. The positioning method according to claim 4, wherein acquiring the measurement of the relative positional change further comprises:

storing data of the relative positional change; and

successively subtracting the data of the relative positional change from the first present position associated with the geographic location, thereby obtaining position data of respective points which have been passed before arrival at the first present position.