Preceding vehicle following control system

• US 6,330,508 B1
• Filed: 06/30/2000
• Issued: 12/11/2001
• Est. Priority Date: 06/30/1999
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Yamamura, Yoshinori, Akabori, Kouichi
• Primary Examiner(s): Nguyen, Tan
• Assistant Examiner(s): Tran, Dalena
• Application Number:
  US09/609,242
• Time in Patent Office: 529 Days
• Field of Search: 701/93, 701/96, 701/97, 701/301, 180/333, 123/352, 318/568.1, 318/570, 318/571, 318/587, 340/435, 340/903, 340/988
• US Class Current: 701/96
• CPC Class Codes: B60K 31/0008 including means for detecting potential obstacles in vehicle path
• CPC Class Codes: B60K 31/047 the memory being digital
• CPC Class Codes: B60W 2710/105 Output torque
• CPC Class Codes: B60W 2720/106 Longitudinal acceleration
• CPC Class Codes: F16H 61/66 specially adapted for continuously variable gearings control of exclusively fluid gearing F16H61/38

Abstract

A preceding vehicle following control apparatus includes a speed sensor for sensing a vehicle speed of a controlled vehicle, a spacing sensor for sensing a spacing or distance from the controlled vehicle to a preceding vehicle, and a following controller. In addition to a following mode for controlling the driving/braking force of the controlled vehicle in accordance with the spacing and the vehicle speed, the following controller has a wait mode, an auto-stop mode and a release mode. The following controller initially sets the control mode to the wait mode, and changes the control mode from the wait mode to one of the auto-stop mode and the following mode depending on whether the controlled vehicle is in a stop state or not. The controller changes the control mode between the auto-stop mode and the following mode in accordance with the spacing and the vehicle speed, changes the control mode to the release mode in response to a driver'"'"'s operation such as a transmission range changing operation and a braking operation, and returns the control mode from the release mode to the wait mode in response to a driver'"'"'s accelerating or braking operation.

Claims

1. A preceding vehicle following control apparatus for a controlled vehicle, comprising:

a following controller

collecting input information on vehicle operating conditions of the controlled vehicle, inclusive of a sensed actual vehicle speed of the controlled vehicle and a sensed actual vehicle spacing from the controlled vehicle to a preceding vehicle,

controlling a longitudinal force of the controlled vehicle in accordance with the actual vehicle speed and the actual vehicle spacing in a following mode,

setting a control mode initially to a wait mode,

changing the control mode from the wait mode to one of the following mode and an auto-stop mode to hold the controlled vehicle in a stop state by producing a braking force,

allowing the control mode to change among the auto-stop mode, the following mode and a release mode to stop a driving force control and prevent abrupt decrease of a braking force of the controlled vehicle, and

returning the control mode to the wait mode from the release mode.

2. The preceding vehicle following control apparatus as claimed in claim 1, wherein the following control apparatus further comprises an input section for sensing the vehicle operating conditions and supplying the input information to the following controller, the input section comprises a speed sensor sensing a vehicle operating condition to determine the actual vehicle speed of the controlled vehicle, a spacing sensor sensing the actual vehicle spacing from the controlled vehicle to a preceding vehicle, and an input device producing a start command signal to start a following control, the following controller is configured to set the control mode to the wait mode in response to the start command signal, and to perform one of a spacing control to bring the actual spacing closer to a desired spacing, and a speed control to bring the actual vehicle speed closer to a preset vehicle speed, the following controller is configured to determine a desired vehicle speed in accordance with the vehicle spacing and to control at least one of a driving force and a braking force of the controlled vehicle in accordance with at least one of the desired vehicle speed and the preset vehicle speed in the following control mode, and the following controller is further configured to change the control mode from the wait mode to one of the following mode and the auto-stop mode in accordance with the input information, and to allow the control mode to change among the auto-stop mode, the following mode and the release mode in accordance with the input information.

3. The preceding vehicle following control apparatus as claimed in claim 1, wherein the following controller is configured to effect:

(i) a wait-to-stop mode change from the wait mode to the auto-stop mode if an automatic transmission of the controlled vehicle is in a drive range, and at the same time the controlled vehicle is in a stop state;

(ii) a wait-to-follow mode change from the wait mode to the following mode if the automatic transmission is in the drive range, and at the same time a brake system of the controlled vehicle is in an inoperative state;

(iii) a stop-to-follow mode change from the auto-stop mode to the following mode if the actual vehicle spacing sensed by the spacing sensor increases;

(iv) a follow-to-stop mode change from the following mode to the auto-stop mode if the actual vehicle spacing is equal to or smaller than a predetermined spacing value and at the same time the actual vehicle speed is equal to or lower than a predetermined speed value;

(v) a stop-to-release mode change from the auto-stop mode to the release mode in response to a driver'"'"'s operation which is one of a steering operation and a transmission'"'"'s range change operation;

(vi) a release-to-stop mode change from the release mode to the auto-stop mode if the controlled vehicle is in the stop state and at the same time the automatic transmission is in the drive range;

(vii) a follow-to-release mode change from the following mode to the release mode in response to a driver'"'"'s operation which is one of an accelerating operation, a decelerating operation and a driver'"'"'s range change operation;

(viii) a release-to-follow mode change from the release mode to the following mode if the controlled vehicle is in a running state and at the same time the automatic transmission is in the drive range; and

(ix) a release-to-wait mode change from the release mode to the wait mode in response to a driver'"'"'s operation to manipulate at least one of a driving force and a braking force.

4. The preceding vehicle following control apparatus as claimed in claim 1, wherein the following controller is configured to control the vehicle speed in accordance with a preset vehicle speed in the following mode, and to allow the preset vehicle speed to be adjusted in the auto-stop mode.

5. The preceding vehicle following control apparatus as claimed in claim 1, wherein the following controller is configured to control the vehicle speed in accordance with a preset vehicle speed in the following mode, and to allow the preset vehicle speed to be adjusted in the wait mode.

6. The preceding vehicle following.control apparatus as claimed in claim 1, wherein the following control apparatus further comprises an input device determining a preset vehicle speed, and the following controller is configured to control the actual vehicle speed in accordance with the preset vehicle speed in the following mode, and to adjust the preset vehicle speed in accordance with a signal from the input device in at least one of the auto-stop mode and the wait mode.

7. The preceding vehicle following control apparatus as claimed in claim 1, wherein the following controller is configured to effect a wait-to-stop mode change from the wait mode to the auto-stop mode in response to a driver'"'"'s braking operation when the controlled vehicle is in a stop state.

8. The preceding vehicle following control apparatus as claimed in claim 1, wherein the following controller is configured to effect a release-to-wait mode change from the release mode to the wait mode in response to a driver'"'"'s operation for increasing a braking force of the controlled vehicle.

9. The preceding vehicle following control apparatus as claimed in claim 1, wherein the following controller is configured to decrease the braking force gradually from a level in the following mode upon a follow-to-release mode change from the following mode to the release mode, and to effect a release-to-wait mode change from the release mode to the wait mode if the braking force becomes equal to or lower than a predetermined braking force value.

10. The preceding vehicle following control apparatus as claimed in claim 1, wherein the following controller is configured to perform, in the release mode, one of a brake force decreasing control to decrease the braking force gradually in accordance with at least one of the vehicle spacing to a preceding vehicle, and the vehicle speed of the controlled vehicle, and a brake force holding control to hold the braking force, and to effect a release-to-wait mode change from the release mode to the wait mode in response to one of a first release-to-wait mode change condition signal which is produced if the braking force becomes equal to or lower than a predetermined braking force value, and a second release-to-wait mode change condition signal which is produced in response to a driver'"'"'s operation for manipulating one of braking force and driving force.

11. The preceding vehicle following control apparatus as claimed in claim 1, wherein the following controller is configured to allow a wait-to-stop mode change from the wait mode to the auto-stop mode if and only if the controlled vehicle is in a stop state, to allow a wait-to-follow mode change the wait mode to the following mode if and only if the controlled vehicle is not in the stop state, to change the control mode between the auto-stop mode and the following mode in accordance with at least one of the actual vehicle spacing and the actual vehicle speed, to change the control mode to the release mode from one of the auto-stop mode and the following mode in response to a driver'"'"'s first operation, and to change the control mode to the wait mode only from the release mode in response to a driver'"'"'s second operation.

12. The preceding vehicle following control apparatus as claimed in claim 11, wherein the following control apparatus comprises an input device detecting a driver'"'"'s driving operation, a second input device detecting a driver'"'"'s braking operation and a third input device detecting a driver'"'"'s transmission shift operation, the driver'"'"'s first operation being one of the driver'"'"'s driving operation, the driver'"'"'s braking operation and the driver'"'"'s shift operation, the driver'"'"'s second operation being one of the driver'"'"'s driving operation and the driver'"'"'s braking operation.

13. The preceding vehicle following control apparatus as claimed in claim 3, wherein the following controller is configured to effect the stop-to-follow mode change from the auto-stop mode to the following mode if an amount of increase in the actual vehicle spacing sensed by the spacing sensor is equal to or greater than a predetermined value, and to effect the stop-to-release mode change from the auto-stop mode to the release mode in response to a driver'"'"'s operation which is one of a transmission range change operation to shift an automatic transmission out of a drive range, and a steering operation increasing a steering amount to a value equal to or greater than a predetermined value.

14. A preceding vehicle following control apparatus for a controlled vehicle, comprising:

collecting means for collecting input information on vehicle operating conditions of the controlled vehicle, the input information including a sensed actual vehicle speed of the controlled vehicle and a sensed actual vehicle spacing from the controlled vehicle to a preceding vehicle;

controlling means for controlling at least one of driving force and braking force of the controlled vehicle in accordance with the actual vehicle speed and the actual vehicle spacing in a following mode;

first mode changing means for changing a control mode from a wait mode to an auto-stop mode for holding the controlled vehicle in a stop state, in response to a wait-to-stop condition signal produced in accordance with the input information;

second mode changing means for changing the control mode from the wait mode to the following mode in response to a wait-to-follow condition signal produced in accordance with the input information;

releasing means for changing the control mode from one of the auto-stop mode and the following mode, to a release mode in response to a release condition signal produced in accordance with the input information; and

returning means for returning the control mode to the wait mode from the release mode in response to a release-to-wait condition signal produced in accordance with the input information.

15. The preceding vehicle following control apparatus as claimed in claim 14, further comprising discriminating means for producing the wait-to-stop condition signal if a transmission of the controlled vehicle is in a predetermined driving state and at the same time the controlled vehicle is in the stop state, producing the wait-to-follow condition signal if the transmission is in the driving state and at the same time the controlled vehicle is not in the stop state, and producing the release condition signal in response to a driver'"'"'s operation which is a shift operation to bring the transmission out of the predetermined driving state, a braking operation and an accelerating operation.

16. A preceding vehicle following control process, comprising:

performing a following control in one of a following mode for controlling a longitudinal force of the controlled vehicle in accordance with a sensed actual vehicle speed of the controlled vehicle and a sensed actual vehicle spacing from the controlled vehicle to a preceding vehicle, and an auto-stop mode for holding the controlled vehicle in a stop state;

changing a control mode from a wait mode to the auto-stop mode in response to a wait-to-stop condition signal;

changing the control mode from the wait mode to the following mode in response to a wait-to-follow condition signal;

changing the control mode from one of the auto-stop mode and the following mode, to a release mode for canceling the following control, in response to a release condition signal; and

returning the control mode to the wait mode from the release mode in response to a release-to-wait condition signal.

17. The preceding vehicle following control process as claimed in claim 16, wherein the wait-to-stop condition signal is produced only when the controlled vehicle is in a stop state, the wait-to-follow condition signal is produced only when the controlled vehicle is not in the stop state, and the release condition signal is produced in response to a driver'"'"'s operation indicative of a driver'"'"'s intention of canceling the following control.

18. The preceding vehicle following control process as claimed in claim 17, further comprising:

producing the wait-to-stop condition signal if a transmission of the controlled vehicle is in a predetermined drive state;

producing the wait-to-follow condition signal if the transmission is in the drive state, and a brake system of the controlled vehicle is in an inoperative state;

producing a stop-to-follow condition signal to effect a mode change from the auto-stop mode to the following mode, in accordance with the actual vehicle spacing;

producing a follow-to-stop condition signal to effect a mode change from the following mode to the auto-stop mode in accordance with the actual vehicle spacing and the actual vehicle speed;

producing the release condition signal which is one of a stop-to-release condition signal to effect a mode change from the auto-stop mode to the release mode, and a follow-to-release condition signal to effect a mode change from the following mode to the release mode;

producing a release-to-stop condition signal to effect a mode change from the release mode to the auto-stop mode if the controlled vehicle is in the stop state and the transmission is in the drive state;

producing a release-to-follow condition signal to effect a mode change from the release mode to the following mode if the controlled vehicle is not in the stop state and the transmission is in the drive state; and

producing the release-to-wait condition signal in response to a driver'"'"'s operation which is one of the accelerating operation and the braking operation.