Wheel brake/drive force control device

• US 8,714,663 B2
• Filed: 12/15/2006
• Issued: 05/06/2014
• Est. Priority Date: 12/16/2005
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Maeda, Yoshinori, Oshiumi, Yasuhiro, Tsuchida, Michitaka, Okumura, Kazuya, Yoshizue, Kensuke, Sugiyama, Koji, Hosokawa, Akihiro
• Primary Examiner(s): NGUYEN, XUAN LAN T
• Application Number:
  US12/097,629
• Publication Number:
  US 20090051216A1
• Time in Patent Office: 2,699 Days
• Field of Search: 303/140, 303/146, 303/154, 303/155, 303186-190, 701/70
• US Class Current: 303/146
• CPC Class Codes: B60L 15/2036 Electric differentials, e.g. for supporting steering vehicles
• CPC Class Codes: B60T 2270/613 ESP features related thereto
• CPC Class Codes: B60T 8/1755 Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve road vehicle drive control systems for control of driving stability otherwise than by controlling a particular sub-unit B60W30/02
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 10/184 with wheel brakes
• CPC Class Codes: B60W 2520/14 Yaw
• CPC Class Codes: B60W 2520/30 Wheel torque
• CPC Class Codes: B60W 2710/083 Torque
• CPC Class Codes: B60W 2720/30 Wheel torque
• CPC Class Codes: B60W 30/02 Control of vehicle driving stability
• CPC Class Codes: B60W 30/18127 Regenerative braking
• CPC Class Codes: B60W 40/11 Pitch movement
• CPC Class Codes: B60W 40/112 Roll movement
• CPC Class Codes: B60W 40/114 Yaw movement
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

A target braking-driving force Fvn and a target yaw moment Mvn of the entire vehicle are calculated, and when the target braking-driving force Fvn and the target yaw moment Mvn cannot be achieved by the braking-driving forces of the front wheels, a target braking-driving force Fvft and a target yaw moment Mvft of the front wheels are adjusted such that the magnitudes of the braking-driving force and yaw moment of the vehicle produced by the braking-driving forces of the front wheels become the maximum at a ratio between Fvn and Mvn. A target braking-driving force Fvrt and a target yaw moment Mvrt of the rear wheels are calculated on the basis of Fvn, Mvn, Fvft, and Mvft, and similar adjustment is performed for them when necessarily.

Claims

1. A braking-driving-force control apparatus for a vehicle, comprising:

braking-driving force imparting means for imparting braking-driving forces to individual wheels;

means for detecting an amount of driving operation by an occupant;

means for calculating a target braking-driving force of an entire vehicle and a target yaw moment of the entire vehicle based on at least the amount of the driving operation; and

control means for controlling the braking-driving forces of the individual wheels by controlling the braking-driving force imparting means such that a braking-driving force of the entire vehicle and a yaw moment of the entire vehicle approach the target braking-driving force of the entire vehicle and the target yaw moment of the entire vehicle,

wherein one of a wheel group including front wheels and a wheel group including rear wheels is defined as a first wheel group, and the other wheel group is defined as a second wheel group,

wherein the control means includes

first adjustment means, which is operable when the target braking-driving force of the entire vehicle or the target yaw moment of the entire vehicle is outside an achievable range of a braking-driving force of the first wheel group, for adjusting respective values of a target braking-driving force of the vehicle and a target yaw moment of the vehicle which are to be produced by the braking-driving force of the first wheel group to be inside the achievable range of the braking-driving force of the first wheel group,

means for calculating respective values of a target braking-driving force of the vehicle and a target yaw moment of the vehicle which are to be produced by means of a braking-driving force of the second wheel group based on

the target braking-driving force of the entire vehicle and the target yaw moment of the entire vehicle, and

the target braking-driving force of the vehicle and the target yaw moment of the vehicle which are to be produced by the braking-driving force of the first wheel group, and

second adjustment means, which is operable when the target braking-driving force of the vehicle and the target yaw moment of the vehicle which are to be produced by the braking-driving force of the second wheel group are outside an achievable range of the braking-driving force of the second wheel group, for adjusting the respective values of the target braking-driving force of the vehicle and the target yaw moment of the vehicle which are to be produced by the braking-driving force of the second wheel group to be inside the achievable range of the braking-driving force of the second wheel group,

wherein at least one of the first and second adjustment means corrects the target braking-driving force or the target yaw moment to a value which is within achievable ranges of the braking-driving force and yaw moment of the vehicle via the braking-driving forces of the wheels, the value being within an ellipse defined in an orthogonal coordinate system having two axes that correspond to the braking-driving force and yaw moment of the vehicle, respectively, a center of the ellipse being located on the axis corresponding to the braking-driving force, and directions of major and minor radii of the ellipse coinciding with the axes of the orthogonal coordinate system, respectively.

2. A braking-driving-force control apparatus for a vehicle, comprising:

braking-driving force imparting means for imparting braking-driving forces to individual wheels;

means for detecting an amount of driving operation by an occupant;

means for calculating a target braking-driving force of an entire vehicle and a target yaw moment of the entire vehicle based on at least the amount of the driving operation; and

control means for controlling the braking-driving forces of the individual wheels by controlling the braking-driving force imparting means such that a braking-driving force of the entire vehicle and a yaw moment of the entire vehicle approach the target braking-driving force of the entire vehicle and the target yaw moment of the entire vehicle,

wherein one of a wheel group including front wheels and a wheel group including rear wheels is defined as a first wheel group, and the other wheel group is defined as a second wheel group,

wherein the control means includes

first adjustment means, which is operable when the target braking-driving force of the entire vehicle or the target yaw moment of the entire vehicle is outside an achievable range of a braking-driving force of the first wheel group, for adjusting respective values of a target braking-driving force of the vehicle and a target yaw moment of the vehicle which are to be produced by the braking-driving force of the first wheel group to be inside the achievable range of the braking-driving force of the first wheel group,

means for calculating respective values of a target braking-driving force of the vehicle and a target yaw moment of the vehicle which are to be produced by means of a braking-driving force of the second wheel group based on

the target braking-driving force of the entire vehicle and the target yaw moment of the entire vehicle, and

the target braking-driving force of the vehicle and the target yaw moment of the vehicle which are to be produced by the braking-driving force of the first wheel group, and

second adjustment means, which is operable when the target braking-driving force of the vehicle and the target yaw moment of the vehicle which are to be produced by the braking-driving force of the second wheel group are outside an achievable range of the braking-driving force of the second wheel group, for adjusting the respective values of the target braking-driving force of the vehicle and the target yaw moment of the vehicle which are to be produced by the braking-driving force of the second wheel group to be inside the achievable range of the braking-driving force of the second wheel group,

wherein an ellipse in an orthogonal coordinate system defines values within achievable ranges of the braking-driving force and yaw moment of the vehicle via the braking-driving forces of the wheels, and

wherein a major radius and a minor radius of the ellipse are determined in part from a friction coefficient of a road surface on which the vehicle drives.