Control apparatus for vehicle

• US 9,150,074 B2
• Filed: 03/14/2013
• Issued: 10/06/2015
• Est. Priority Date: 03/15/2012
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Kikuchi, Hironobu, Hirayama, Katsuhiko
• Primary Examiner(s): Trammell, James
• Assistant Examiner(s): Stroud, James E
• Application Number:
  US13/829,386
• Publication Number:
  US 20130245889A1
• Time in Patent Office: 936 Days
• US Class Current: 1/1
• CPC Class Codes: B60G 17/016 characterised by their responsiveness, when the vehicle is travelling, to specific motion, a specific condition, or driver input B60G17/017 takes precedence
• CPC Class Codes: B60G 17/0195 characterised by the regulation being combined with other vehicle control systems conjoint control of vehicle sub-units including control of suspension systems B60W10/22
• CPC Class Codes: B60G 17/06 Characteristics of dampers , e.g. mechanical dampersB60G17/015 takes precedence
• CPC Class Codes: B60G 2400/102 vertical
• CPC Class Codes: B60G 2500/10 Damping action or damper
• CPC Class Codes: B60T 2260/06 Active Suspension System
• CPC Class Codes: B60T 8/17555 specially adapted for enhancing driver or passenger comfort, e.g. soft intervention or pre-actuation strategies
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 10/22 including control of suspension systems
• CPC Class Codes: B60W 2510/18 Braking system
• CPC Class Codes: B60W 2510/22 Suspension systems
• CPC Class Codes: B60W 2520/00 Input parameters relating to overall vehicle dynamics
• CPC Class Codes: B60W 2710/182 Brake pressure, e.g. of fluid or between pad and disc
• CPC Class Codes: B60W 2710/226 Damping
• CPC Class Codes: B60W 30/025 related to comfort of drivers or passengers

Abstract

A control apparatus for a vehicle according to the present invention is configured to control a friction brake by calculating a brake attitude control amount outputted from the friction brake such that the acceleration detected by the vertical acceleration sensor becomes an acceleration corresponding to a target sprung state, and to control a damping force variable shock absorber by calculating a damping force control amount of the damping force variable shock absorber such that the stroke speed detected by the stroke sensor becomes a stroke speed corresponding to the target sprung state and/or a target unsprung state.

Claims

1. A control apparatus for a vehicle comprising:

a vertical acceleration sensor configured to detect a sprung vertical acceleration;

a friction brake attitude control unit configured to control a friction brake by calculating a brake attitude control amount outputted from the friction brake such that the sprung vertical acceleration detected by the vertical acceleration sensor becomes an acceleration corresponding to a target sprung state;

a stroke sensor configured to detect a stroke speed of a damping force variable shock absorber;

a damping force control unit configured to control the damping force variable shock absorber by calculating a damping force control amount of the damping force variable shock absorber such that the stroke speed detected by the stroke sensor becomes a stroke speed corresponding to the target sprung state and/or a target unsprung state;

a first feedback control system based on the sprung vertical acceleration and configured by the vertical acceleration sensor and the friction brake attitude control unit; and

a second feedback control system based on the stroke speed and configured by the stroke sensor and the damping force control unit,

wherein the first feedback control system and the second feedback control system are operable in parallel.

2. The control apparatus for a vehicle according to claim 1, further comprising a phase compensation unit configured to compensate for a phase displacement between a detection value of the vertical acceleration sensor and a detection value of the stroke sensor.

3. The control apparatus for a vehicle according to claim 1, wherein the friction brake attitude control unit suppresses a pitch movement of a vehicle body.

4. The control apparatus for a vehicle according to claim 1, wherein the friction brake attitude control unit has a limit value for limiting the brake attitude control amount to a predetermined value such that a change rate of deceleration of the vehicle body becomes a predetermined value or less.

5. The control apparatus for a vehicle according to claim 1, wherein the damping force control unit calculates the damping force control amount on the basis of an active skyhook model which can be estimated, regardless of codes of a sprung speed and the stroke speed.

6. The control apparatus for a vehicle according to claim 1, wherein the damping force control unit estimates a traveling state by developing a four-wheel model on the basis of a bounce term indicating a vertical direction movement of four wheels, a pitch term indicating a vertical direction movement of front and rear wheels, a roll term indicating a vertical direction movement of left and right wheels, and a wrap term indicating a vertical direction movement of diagonal wheels.

7. A control apparatus for a vehicle comprising:

a vertical acceleration sensor configured to detect a sprung vertical acceleration;

a stroke sensor configured to detect a stroke speed of a damping force variable shock absorber;

a controller configured to calculate a brake attitude control amount that makes the sprung vertical acceleration detected by the vertical acceleration sensor become an acceleration corresponding to a target sprung state and to request a braking force of a friction brake in accordance with the brake attitude control amount, and configured to calculate a damping force control amount that makes the stroke speed detected by the stroke sensor become a stroke speed corresponding to the target sprung state and/or a target unsprung state and to request a damping force of the damping force variable shock absorber in accordance with the damping force control amount;

a first feedback control system based on the sprung vertical acceleration and configured by the vertical acceleration sensor and the controller; and

a second feedback control system based on the stroke speed and configured by the stroke sensor and the controller,

wherein the first feedback control system and the second feedback control system are operable in parallel.

8. A control method for a vehicle, comprising the steps of:

controlling, by a controller, a braking force of a friction brake by calculating a brake attitude control amount outputted from the friction brake such that a sprung vertical acceleration detected by a vertical acceleration sensor becomes a sprung vertical acceleration corresponding to a target sprung state; and

controlling, by the controller, a damping force of a damping force variable shock absorber by calculating a damping force control amount of the damping force variable shock absorber such that a stroke speed of the damping force variable shock absorber detected by a stroke sensor becomes a stroke speed corresponding to the target sprung state and/or a target unsprung state, wherein

a first feedback control system based on the sprung vertical acceleration is configured by the vertical acceleration sensor and the controller,

a second feedback control system based on the stroke speed is configured by the stroke sensor and the controller, and

the first feedback control system and the second feedback control system are operated in parallel.