Vehicle body state quantity estimating device

Patent metadata

Field	Value
Publication number	US-2016264148-A1
Application number	US-201615064047-A
Country	US
Kind code	A1
Filing date	Mar 8, 2016
Priority date	Mar 11, 2015
Publication date	Sep 15, 2016
Grant date	—

Abstract

A device includes a road surface input calculating unit that calculates an estimated value of a road surface input to the wheel, by letting an inverse matrix of a product of a vehicle motion model matrix and a wheel speed influencing element model matrix act on a wheel speed of a vehicle. The vehicle motion model matrix represents a mechanical vehicle motion model, and the wheel speed influencing element model matrix using a quantity of influence due to pitch about a center of gravity of a vehicle body, a suspension geometry influence quantity, and a quantity of influence of a change in a rolling radius of the wheel. The device also includes a vehicle body state quantity calculating unit that calculates an estimated value of a vehicle body state quantity by letting the vehicle motion model matrix on the calculated estimated value of the road surface input.

First claim

What is claimed is:

1 . A vehicle body state quantity estimating device adaptable to a vehicle including a wheel speed sensor that obtains a wheel speed of a wheel mounted on the vehicle, comprising:
a road surface input calculating unit that calculates an estimated value of a road surface input to the wheel, by letting an inverse matrix of a product of a vehicle motion model matrix and a wheel speed influencing element model matrix act on the obtained wheel speed, the vehicle motion model matrix representing a mechanical vehicle motion model of the vehicle, the wheel speed influencing element model matrix representing a wheel speed influencing element model using three wheel speed influencing elements as elements that influence the wheel speed, the wheel speed influencing elements comprising a quantity of influence due to pitch about a center of gravity of a vehicle body, a suspension geometry influence quantity, and a quantity of influence of a change in a rolling radius of the wheel; and a vehicle body state quantity calculating unit that calculates an estimated value of a vehicle body state quantity by letting the vehicle motion model matrix on the estimated value of the road surface input calculated by the road surface input calculating unit.

2 . The vehicle body state quantity estimating device according to claim 1 , wherein:
a normalized moment of inertia of the vehicle body of the vehicle is 1, in the vehicle motion model; the wheel speed comprises a wheel speed of a front wheel of the vehicle and a wheel speed of a rear wheel of the vehicle; the road surface input comprises a road surface input to the front wheel of the vehicle and a road surface input to the rear wheel; and the road surface input calculating unit calculates an estimated value of a road surface input to the front wheel, by letting elements of the inverse matrix associated with the front wheel act on the obtained wheel speed of the front wheel, and calculates an estimated value of a road surface input to the rear wheel, by letting elements of the inverse matrix associated with the rear wheel act on the obtained wheel speed of the rear wheel.

3 . The vehicle body state quantity estimating device according to claim 1 , wherein:
a normalized moment of inertia of the vehicle body of the vehicle is 1, in the vehicle motion model; the wheel speed comprises a wheel speed of a front wheel of the vehicle; and the road surface input calculating unit calculates an estimated value of a road surface input to the front wheel, by letting elements of the inverse matrix associated with the front wheel act on the obtained wheel speed of the front wheel, and calculates an estimated value of a road surface input to a rear wheel, by letting a wheel base delay amount of the vehicle act on the estimated value of the road surface input to the front wheel.

4 . A damping control system of a vehicle, comprising:
a sensor that obtains a wheel speed of the vehicle; and an electronic control unit configured to
calculate an estimated value of a road surface input to the wheel, by letting an inverse matrix of a product of a vehicle motion model matrix and a wheel speed influencing element model matrix act on the obtained wheel speed, the vehicle motion model matrix representing a mechanical vehicle motion model of the vehicle, the wheel speed influencing element model matrix representing a wheel speed influencing element model using three wheel speed influencing elements as elements that influence the wheel speed, the wheel speed influencing elements comprising a quantity of influence due to pitch about a center of gravity of the vehicle body, a suspension geometry influence quantity, and a quantity of influence of a change in a rolling radius of the wheel,
calculate an estimated value of a vehicle body state quantity by letting the vehicle motion model matrix act on the calculated estimated value of the road surface input, and
control a power source of the vehicle based on the estimated value of the vehicle body state quantity.

Assignees

• Toyota Motor Co Ltd

Inventors

• Liu Yanqing

Classifications

• B60W40/06 Primary

  Road conditions · CPC title

• B60W2050/0031

  Mathematical model of the vehicle · CPC title

• B60W2520/28

  Wheel speed · CPC title

• B60W40/10 Primary

  related to vehicle motion · CPC title

• G01H17/00

  Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves, not provided for in the other groups of this subclass · CPC title