Travel direction determination apparatus, map matching apparatus, travel direction determination method, and computer readable medium

Patent metadata

Field	Value
Publication number	US-10247558-B2
Application number	US-201615201724-A
Country	US
Kind code	B2
Filing date	Jul 5, 2016
Priority date	Jan 7, 2014
Publication date	Apr 2, 2019
Grant date	Apr 2, 2019

Abstract

A travel direction determination apparatus is provided, including: a sensor signal acquisition unit that acquires sensor signals from sensors mounted in a mobile device; a first travel direction calculation unit that calculates a travel direction of the user without relying on a walking state of the user; a second travel direction calculation unit that calculates the travel direction of the user based on the sensor signals when the user who holds the mobile device is in a walking state; and a determination unit that determines the travel direction of the user first to the travel direction calculated by the first travel direction calculation unit, and then to the travel direction calculated by the second travel direction calculation unit, responding to changes in the state of the user from non-walking state to walking state.

First claim

What is claimed is:

1. A travel direction determination apparatus, comprising:
a sensor signal acquisition unit that acquires sensor signals of sensors mounted in a mobile device;
a first travel direction calculation unit that calculates a travel direction of a user without relying on a walking state of the user;
a second travel direction calculation unit that calculates the travel direction of the user based on the sensor signals when the user who holds the mobile device is in a walking state;
a walk detection unit that detects whether or not the user is in the walking state based on a distribution value of a synthesis acceleration of a plurality of accelerometers mounted in the mobile device, counts the number of pulses of periodic signals that accompany the walking state; and detects information of the number of steps taken by the user; and
a determination unit that first determines the travel direction of the user from an output calculated by the first travel direction calculation unit as the travel direction of the user until it is detected that the user took a predetermined number of steps since the state of the user has changed from the non-walking state to the walking state, and then determines the travel direction of the user from an output calculated by the second travel direction calculation unit after the predetermined number of steps was detected as the travel direction of the user, responding to changes in the state of the user from non-walking state to walking state.

2. The travel direction determination apparatus according to claim 1 , wherein the determination unit determines the travel direction calculated by the first travel direction calculation unit as the travel direction of the user when the state of the user is the non-walking state.

3. The travel direction determination apparatus according to claim 1 , wherein the determination unit determines the travel direction calculated by the first travel direction calculation unit as the travel direction of the user during a predetermined period after the state of the user has changed from the non-walking state to the walking state, and determines the travel direction calculated by the second travel direction calculation unit as the travel direction of the user after the predetermined period has elapsed.

4. The travel direction determination apparatus according to claim 1 , wherein the first travel direction calculation unit calculates the travel direction of the user responding to changes in the orientation of the mobile device based on the sensor signals.

5. The travel direction determination apparatus according to claim 4 , wherein the first travel direction calculation unit calculates from the sensor signals rotation angles about a gravity axis of the mobile device, and calculates the travel direction of the user from a cumulative value of the calculation results of rotation angle.

6. The travel direction determination apparatus according to claim 5 , wherein the first travel direction calculation unit calculates the rotation angle about the gravity axis of the mobile device based on the sensor signals of the sensors that detect the rotation angles of two or more axial directions of the mobile device.

7. The travel direction determination apparatus according to claim 6 , wherein the first travel direction calculation unit selects the two sensor signals having the largest and the second largest absolute values of signal component about the gravity axis out of the sensor signals of the sensors that detect the rotation angles of three axial directions of the mobile device, and calculates the rotation angle about the gravity axis of the mobile device based on the selected two sensor signals.

8. The travel direction determination apparatus according to claim 1 , wherein the sensor signal acquisition unit acquires sensor signals of at least either one of angular velocity sensor and accelerometer mounted in the mobile device.

9. The travel direction determination apparatus according to claim 4 , wherein the sensor signal acquisition unit acquires sensor signals output from geomagnetic sensor mounted in the mobile device, and the first travel direction calculation unit calculates the travel direction of the user based on the sensor signals.

10. A travel direction determination method, comprising:
acquiring sensor signals of sensors mounted in a mobile device;
calculating, by a first travel direction calculation unit, a travel direction of a user without relying on a walking state of the user;
calculating, by a second travel direction calculation unit, the travel direction of the user based on the sensor signals when the user who holds the mobile device is in a walking state;
detecting whether or not the user is in the walking state based on a distribution value of a synthesis acceleration of a plurality of accelerometers mounted in the mobile device;
counting the number of pulses of periodic signals that accompany the walking state;
detecting information of the number of steps taken by the user;
first determining the travel direction of the user from an output calculated by the first travel direction calculation unit as the travel direction of the user until it is detected that the user took a predetermined number of steps since the state of the user has changed from the non-walking state to the walking state, and then determining the travel direction of the user from an output calculated by the second travel direction calculation unit after the predetermined number of steps was detected as the travel direction of the user, responding to changes in the state of the user from non-walking state to walking state.

11. A map matching apparatus comprising:
the travel direction determination apparatus according to claim 1 ;
a storage unit that stores an initial position of the user and map information; and
a position decision unit that decides a position of the user on a map based on a movement amount from the initial position according to travel direction information of the user which is output from the travel direction output apparatus.

12. A computer readable medium storing therein programs that, when executed by a computer, causes the computer to function as the travel direction determination apparatus according to claim 1 .

13. The travel direction determination apparatus according to claim 1 , wherein the determination unit first determines the travel direction calculated by the first travel direction calculation unit as the travel direction of the user, and then determines the travel direction calculated by the second travel direction calculation unit as the travel direction of the user, responding to a U-turn made by the user.

Assignees

• Asahi Chemical Ind

Inventors

• Kobayashi Shiro
• Konda Masahiro
• Akagi Yuko

Classifications

• G01P13/02

  Indicating direction only, e.g. by weather vane · CPC title

• G01C21/30 Primary

  Map- or contour-matching · CPC title