Velocity estimation device

Patent metadata

Field	Value
Publication number	US-10732299-B2
Application number	US-201415110048-A
Country	US
Kind code	B2
Filing date	Dec 16, 2014
Priority date	Jan 8, 2014
Publication date	Aug 4, 2020
Grant date	Aug 4, 2020

Abstract

A velocity estimation device including an acceleration sensor and a yaw rate sensor is provided. The velocity estimation device determines an initial velocity value of a mobile object based on a velocity estimation expression, an integrated value of acceleration detected by the acceleration sensor, and a relative azimuth calculated from detected yaw rates. The velocity estimation device estimates the velocity of the mobile object based on the initial velocity value and the integrated value of acceleration. In the velocity estimation expression, a magnitude of the velocity vector is constrained by the velocity of the mobile object and a time variation of a direction of the velocity vector is constrained by a time variation of the azimuth of the mobile object in the traveling direction.

First claim

What is claimed is:

1. A velocity estimation device comprising:
an acceleration sensor that moves together with a mobile object to detect an acceleration of the mobile object;
a yaw rate sensor that detects a yaw rate of the mobile object; and
a computer including a processor and configured to
sequentially determine a traveling direction acceleration to determine a plurality of traveling direction accelerations, the traveling direction acceleration being a traveling direction component of a value detected by the acceleration sensor;
sequentially calculate an acceleration integrated value by integrating the plurality of traveling direction accelerations determined by the computer and sequentially calculate a relative azimuth to the traveling direction at a base point of time through integrating yaw rates detected by the yaw rate sensor;
acquire information of a satellite signal from a satellite included in a satellite positioning system;
calculate a satellite direction velocity on a basis of the information of the satellite signal, the satellite direction velocity being a component of a velocity of the mobile object in a direction to the satellite;
calculate a line-of-sight vector from the mobile object to the satellite based on the information of the satellite signal;
determine an initial velocity value of the mobile object based on (i) a velocity estimation expression showing a relationship among the satellite direction velocity, the line-of-sight vector, the velocity of the mobile object, and the relative azimuth of the mobile object, (ii) the satellite direction velocity calculated by the computer, (iii) the line-of-sight vector calculated by the computer, and (iv) the relative azimuth calculated by the computer; and
estimate the velocity of the mobile object based on the acceleration integrated value calculated by the computer and the initial velocity value determined by the computer, wherein

in an expression showing the relationship among the satellite direction velocity, the line-of-sight vector, and a velocity vector of the mobile object in the velocity estimation expression, a magnitude of the velocity vector is constrained by the velocity of the mobile object, and a time variation of a direction of the velocity vector is constrained by a time variation of the relative azimuth of the mobile object.

2. A velocity estimation device comprising:
an acceleration sensor that moves together with a mobile object to detect an acceleration of the mobile object; and
a computer including a processor and configured to
sequentially determine a traveling direction acceleration to determine a plurality of traveling direction accelerations, the traveling direction acceleration being a traveling direction component of a value detected by the acceleration sensor;
sequentially calculate an acceleration integrated value through integrating the plurality of traveling direction accelerations determined by the computer;
acquire information of a satellite signal from a satellite included in a satellite positioning system;
calculate a satellite direction velocity based on the information of the satellite signal, the satellite direction velocity being a component of a velocity of the mobile object in a direction to the satellite;
calculate a line-of-sight vector from the mobile object to the satellite based on the information of the satellite signal;
determine an azimuth of the mobile object;
determine an initial velocity value of the mobile object based on (i) a velocity estimation expression showing a relationship among the satellite direction velocity, the line-of-sight vector, the velocity of the mobile object, the azimuth of the mobile object, and a clock drift, (ii) the satellite direction velocity calculated by the computer, and (iii) the line-of-sight vector calculated by the computer; and
estimate the velocity of the mobile object based on the acceleration integrated value calculated by the computer and the initial velocity value determined by the computer, wherein

in an expression showing the relationship among the satellite direction velocity, the line-of-sight vector, a velocity vector of the mobile object, and the clock drift in the velocity estimation expression, a magnitude of the velocity vector is constrained by the velocity of the mobile object and the clock drift is constrained by a constraint condition that a time variation of the clock drift is linear.

Assignees

• Denso Corp

Inventors

• Kumabe Seigou
• Takeyama Kojiro
• Kojima Yoshiko

Classifications

• G01S19/49

  whereby the further system is an inertial position system, e.g. loosely-coupled · CPC title

• G01S5/011

  Identifying the radio environment · CPC title

• G01S19/52 Primary

  Determining velocity · CPC title