Position calculating method and position calculating device

• US 8,781,776 B2
• Filed: 04/11/2011
• Issued: 07/15/2014
• Est. Priority Date: 04/09/2010
• Status: Expired due to Fees

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Kumar, Anand, Onda, Kenji
• Primary Examiner(s): HENSON, MISCHITA L
• Application Number:
  US13/084,469
• Publication Number:
  US 20110257920A1
• Time in Patent Office: 1,191 Days
• Field of Search: 702 94- 95, 702141-142
• US Class Current: 702/94
• CPC Class Codes: G01C 21/165 combined with non-inertial navigation instruments
• CPC Class Codes: G01C 21/28 with correlation of data from several navigational instruments
• CPC Class Codes: G01S 19/49 whereby the further system is an inertial position system, e.g. loosely-coupled

Abstract

A method of calculating the position of a moving body includes: detecting a movement direction of the moving body; calculating a velocity vector of the moving body using a detection result of an acceleration sensor installed in the moving body; correcting the velocity vector using the movement direction; and calculating the position of the moving body using the corrected velocity vector.

Claims

1. A non-transitory computer readable medium comprising executable instructions, that when executed, cause a processor to execute a method of calculating a position of a moving body, the method comprising:

detecting a movement direction of the moving body;

calculating a velocity vector of the moving body using a detection result of an acceleration sensor installed in the moving body;

correcting the velocity vector using the movement direction;

calculating the position of the moving body using the corrected velocity vector; and

detecting rotation of the moving body,

wherein the correcting of the velocity vector includes changing the size of the velocity vector when the moving body rotates based on the comparison of the velocity of the moving body at the time of the rotation with recorded velocity at start of rotation.

2. The method according to claim 1,

wherein the correcting of the velocity vector includes correcting a direction of the velocity vector to the detected movement direction.

5. The method according to claim 1,

wherein the moving body is a vehicle.

3. A non-transitory computer readable medium comprising executable instructions, that when executed, cause a processor to execute a method of calculating a position of a moving body, comprising:

detecting a movement direction of the moving body;

calculating a velocity vector of the moving body using a detection result of an acceleration sensor installed in the moving body;

calculating the position of the moving body using the velocity vector; and

correcting the calculated position using the detected movement direction based on the comparison of the velocity of the moving body at the time of the rotation with recorded velocity at start of rotation.

4. The method according to claim 3, further comprising:

calculating a posture of the moving body using a detection result of a gyro sensor installed in the moving body; and

performing coordinate transformation of the detection result of the acceleration sensor to an absolute direction by coordinate transformation of a relative detection direction of the acceleration sensor with respect to the moving body to the absolute direction using the calculated posture,

wherein in the calculating of the velocity vector, the velocity vector is calculated using a detection result after the coordinate transformation.

6. A position calculating device installed in a moving body to calculate a position of the moving body, comprising:

an acceleration sensor;

a movement direction detecting section which detects a movement direction of the moving body;

a velocity vector calculating section which calculates a velocity vector of the moving body using a detection result of the acceleration sensor;

a velocity vector correcting section which corrects the velocity vector using the movement direction detected by the movement direction detecting section; and

a position calculating section which calculates the position of the moving body using the velocity vector corrected by the velocity vector correcting section;

wherein when rotation of the moving body is detected, the velocity vector is corrected by changing the size of the velocity vector based on the comparison of the velocity of the moving body at the time of the rotation with recorded velocity at start of rotation.

7. A position calculating device installed in a moving body to calculate a position of the moving body, comprising:

an acceleration sensor;

a movement direction detecting section which detects a movement direction of the moving body;

a velocity vector calculating section which calculates a velocity vector of the moving body using a detection result of the acceleration sensor;

a position calculating section which calculates the position of the moving body using the velocity vector calculated by the velocity vector calculating section;

a position correcting section which corrects the position calculated by the position calculating section using the detected movement direction; and

detecting rotation of the moving body,

wherein the correcting of the velocity vector includes changing the size of the velocity vector when the moving body rotates based on the comparison of the velocity of the moving body at the time of the rotation with recorded velocity at start of rotation.