Congestion sign detection method, program, and congestion sign detection device

• US 9,646,492 B2
• Filed: 03/07/2014
• Issued: 05/09/2017
• Est. Priority Date: 03/08/2013
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Koshizen, Takamasa
• Primary Examiner(s): PAIGE, TYLER D
• Application Number:
  US14/766,581
• Publication Number:
  US 20150379871A1
• Time in Patent Office: 1,159 Days
• Field of Search: 701118, 340905
• CPC Class Codes: B60W 40/04 Traffic conditions
• CPC Class Codes: G08G 1/00 Traffic control systems for road vehicles arrangement of road signs or traffic signals E01F9/00 ; automatic vehicle control B62D
• CPC Class Codes: G08G 1/01 Detecting movement of traffic to be counted or controlled G08G1/07 - G08G1/14 take precedence
• CPC Class Codes: G08G 1/0112 from the vehicle, e.g. floating car data [FCD]
• CPC Class Codes: G08G 1/0133 for classifying traffic situation
• CPC Class Codes: G08G 1/13 the indicator being in the form of a map

Abstract

A congestion sign detection method that is executed by a congestion sign detection device 10 which includes three-dimensional acceleration sensor 14 that acquires acceleration information in each axis direction of an X axis, a Y axis, and a Z axis forming an orthogonal coordinate system of the three-dimensional space. The method includes: an input data calculation step of calculating an acceleration vector using the acceleration information acquired by the three-dimensional acceleration sensor 14, and calculating a norm of a difference of the vectors at two different timings as input data; a frequency analysis step of calculating an autocorrelation of the input data and calculating a power spectrum by performing a Fourier transform on the autocorrelation; an angle information acquisition step of converting the power spectrum into angle information; and a congestion sign detection step of detecting congestion sign according to the angle information.

Claims

1. A congestion sign detection method that is executed by an electronic device which is movable together with a moving body and includes an acceleration sensor configured to acquire acceleration information of the electronic device in each axis direction of a first axis to a third axis forming an orthogonal coordinate system of the three-dimensional space, the method comprising:

an input data calculation step of calculating an acceleration vector in the three-dimensional space using the acceleration information acquired by the acceleration sensor, and calculating a norm of a difference of the vectors at two different timings as input data;

a frequency analysis step of calculating an autocorrelation of the input data and calculating a power spectrum by performing a Fourier transform on the autocorrelation;

an angle information acquisition step of converting the power spectrum into angle information; and

a congestion sign detection step of detecting a congestion sign of the moving body according to the angle information.

2. The congestion sign detection method according to claim 1,

wherein, in the angle information acquisition step, a single regression line at a low frequency region where a frequency of the power spectrum is equal to or lower than a predetermined frequency is calculated, and a slope of the single regression line is converted into the angle information.

3. The congestion sign detection method according to claim 1,

wherein, in the congestion sign detection step, the congestion sign of the moving body is detected according to a variation of the angle information corresponding to time.

4. A congestion sign detection method that is executed by a congestion sign detection system which includes a server device, and an electronic device that is movable together with a moving body and includes an acceleration sensor configured to acquire acceleration information of the electronic device in each axis direction of a first axis to a third axis forming an orthogonal coordinate system of the three-dimensional space and a positioning signal receiver configured to acquire present position information of the electronic device, the method comprising:

an input data calculation step of causing the electronic device to calculate an acceleration vector in the three-dimensional space using the acceleration information acquired by the acceleration sensor, and to calculate a norm of a difference of the vectors at two different timings as input data;

a frequency analysis step of causing the electronic device to calculate an autocorrelation of the input data and calculating a power spectrum by performing a Fourier transform on the autocorrelation;

an angle information acquisition step of causing the electronic device to convert the power spectrum into angle information;

an electronic device information transmission step of causing the electronic device to transmit the angle information and the present position information acquired by the positioning signal receiver to the server device;

a position range congestion sign detection step of causing the server device to detect a congestion sign of the moving body within a position range by the number and proportion of the electronic devices in which an absolute value of the angle within the appropriate position range becomes equal to or greater than a predetermined value using the present position information and the angle information received from at least one or more electronic devices; and

a server information transmission step of causing the server device to transmit information of the congestion sign of the moving body within the position range to the electronic device in the position range.

5. A non-transitory computer-readable storage medium storing a program for causing a computer configuring an electronic device, which is movable together with a moving body and includes an acceleration sensor configured to acquire acceleration information of the electronic device in each axis direction of a first axis to a third axis forming an orthogonal coordinate system of the three-dimensional space, to function as:

an input data calculation portion configured to calculate an acceleration vector in the three-dimensional space using the acceleration information acquired by the acceleration sensor, and calculate a norm of a difference of the vectors at two different timings as input data;

a frequency analysis portion configured to calculate an autocorrelation of the input data calculated by the input data calculation portion, and calculating a power spectrum by performing a Fourier transform on the autocorrelation;

an angle information acquisition portion configured to convert the power spectrum calculated by the frequency analysis portion into angle information; and

a congestion sign detection portion configured to detect a congestion sign of the moving body according to the angle information acquired by the angle information acquisition portion.

6. The non-transitory computer-readable storage medium according to claim 5,

wherein the angle information acquisition portion calculates a single regression line at a low frequency region where a frequency of the power spectrum is equal to or lower than a predetermined frequency, and converts a slope of the single regression line into the angle information.

7. The non-transitory computer-readable storage medium according to claim 5,

wherein the congestion sign detection portion detects the congestion sign of the moving body according to a variation of the angle information corresponding to time.

8. A congestion sign detection device which is movable together with a moving body, the device comprising:

an acceleration sensor configured to acquire acceleration information of the congestion sign detection device in each axis direction of a first axis to a third axis forming an orthogonal coordinate system of the three-dimensional space; and

a processor,

wherein the processor is functioned as;

an input data calculation portion configured to calculate an acceleration vector in the three-dimensional space using the acceleration information acquired by the acceleration sensor, and calculating a norm of a difference of the vectors at two different timings as input data;

a frequency analysis portion configured to calculate an autocorrelation of the input data calculated by the input data calculation portion, and calculating a power spectrum by performing a Fourier transform on the autocorrelation;

an angle information acquisition portion configured to convert the power spectrum calculated by the frequency analysis portion into angle information; and

a congestion sign detection portion configured to detect a congestion sign of the moving body according to the angle information acquired by the angle information acquisition portion.

9. The congestion sign detection device according to claim 8,

wherein the angle information acquisition portion calculates a single regression line at a low frequency region where a frequency of the power spectrum is equal to or lower than a predetermined frequency, and converts a slope of the single regression line into the angle information.

10. The congestion sign detection device according to claim 8,

wherein the congestion sign detection portion detects the congestion sign of the moving body according to a variation of the angle information corresponding to time.