Vehicle speed control system

• US 7,092,811 B2
• Filed: 10/31/2003
• Issued: 08/15/2006
• Est. Priority Date: 05/16/2000
• Status: Expired due to Term

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Ino, Junsuke, Sudo, Hideki, Adachi, Kazutaka, Ishizu, Takeshi
• Primary Examiner(s): ARTHUR JEANGLAUDE, GERTRUDE
• Application Number:
  US10/697,000
• Publication Number:
  US 20040093144A1
• Time in Patent Office: 1,019 Days
• Field of Search: 701 93- 96, 701/110, 180170-171, 180/179, 123/339.1, 123/339.14, 123350-352
• US Class Current: 701/93
• CPC Class Codes: B60K 31/0083 responsive to centrifugal force acting on vehicle due to the path it is following
• CPC Class Codes: B60K 31/047 the memory being digital
• CPC Class Codes: B60W 2050/0012 Feedforward or open loop systems
• CPC Class Codes: B60W 2520/125 Lateral acceleration
• CPC Class Codes: B60W 30/18145 Cornering
• CPC Class Codes: F16H 61/66 specially adapted for continuously variable gearings control of exclusively fluid gearing F16H61/38
• CPC Class Codes: F16H 61/66259 using electrical or electronical sensing or control means

Abstract

A vehicle speed control system for a vehicle comprises a lateral acceleration sensor, a vehicle speed sensor, a target vehicle speed setting device, a drive system of the vehicle, and a controller connected. The controller is arranged to calculate a correction quantity on the basis of the lateral acceleration and the vehicle speed, to calculate a command vehicle speed on the basis of the vehicle speed, the target vehicle speed, a variation of the command vehicle speed and the correction quantity, and to control the drive system to bring the vehicle speed closer to the command vehicles speed.

Claims

1. A vehicle speed control system for a vehicle, comprising:

a command vehicle speed variation determining section that calculates a command vehicle speed variation on the basis of a deviation between a vehicle speed and a target vehicle speed set by an operator;

a correction quantity calculating section that detects a lateral acceleration of the vehicle and calculates a correction quantity according to the lateral acceleration;

a command vehicle speed calculating section that calculates a command vehicle speed by subtracting the correction quantity from a first value calculated from at least one of the target vehicle speed set by the operator and a second value calculated from the vehicle speed and the command vehicle speed variation; and

said correction quantity calculation section determining the correction quantity so that the correction quantity becomes smaller as the vehicle speed becomes higher.

2. The vehicle speed control system as claimed in claim 1, wherein said correction quantity calculating section calculates the lateral acceleration from the vehicle speed and a value obtained by processing one of a steer angle and a yaw rate by means of a low pass filter, calculates the correction quantity according to the lateral acceleration, and varies the correction quantity by varying a cutoff frequency of the low pass filter according to the vehicle speed.

3. A method for controlling a vehicle speed of a vehicle, comprising:

calculating a command vehicle speed variation on the basis of a deviation between a vehicle speed and a target vehicle speed set by an operator;

detecting a lateral acceleration of the vehicle;

calculating a correction quantity according to the lateral acceleration;

calculating a command vehicle speed by subtracting the correction quantity from a value calculated from at least one of the target vehicle speed set by the operator and a value calculated based on the vehicle speed and the command vehicle speed variation; and

determining the correction quantity so that the correction quantity becomes smaller as the vehicle speed becomes higher.

4. A vehicle speed control system for a vehicle, comprising:

a vehicle speed sensor that senses a vehicle speed of the vehicle;

a command vehicle speed variation determining section, connected to the vehicle speed sensor, that calculates a command vehicle speed variation on the basis of a deviation between the vehicle speed and a target vehicle speed;

a lateral acceleration detector that detects a lateral acceleration of the vehicle;

a correction quantity calculating section, connected to the lateral acceleration detector, that calculates a correction quantity according to the lateral acceleration and the vehicle speed, so that the correction quantity becomes higher as the lateral acceleration becomes higher; and

a command vehicle speed calculating section, connected to the command vehicle speed variation determining section and the correction quantity calculating section, that calculates a command vehicle speed by subtracting the correction quantity from a first value calculated from a sum of the vehicle speed and the command vehicle speed variation when acceleration of the vehicle is requested,

wherein the correction quantity calculating section determines the correction quantity such that the correction quantity becomes smaller as the vehicle speed becomes higher.