System for influencing the speed of a motor vehicle

• US 7,774,123 B2
• Filed: 05/19/2005
• Issued: 08/10/2010
• Est. Priority Date: 11/21/2002
• Status: Active Grant

• Current Assignee: Lucas Automotive GmbH (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: Lucas Automotive GmbH (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Schroder, Marko
• Primary Examiner(s): Black; Thomas G
• Assistant Examiner(s): LOUIE, WAE LENNY
• Application Number:
  US11/132,651
• Publication Number:
  US 20050240335A1
• Time in Patent Office: 1,909 Days
• Field of Search: 701/45, 701/93, 701/301, 701/96, 340/435, 702/147
• US Class Current: 701/96
• CPC Class Codes: B60K 31/0008 including means for detecting potential obstacles in vehicle path
• CPC Class Codes: B60T 2201/08 Lane monitoring; Lane Keeping Systems
• CPC Class Codes: B60T 2201/081 using distance control
• CPC Class Codes: B60W 2520/14 Yaw
• CPC Class Codes: B60W 2552/05 Type of road, e.g. motorways, local streets, paved or unpaved roads
• CPC Class Codes: B60W 2552/10 Number of lanes
• CPC Class Codes: B60W 2552/20 Road profile, i.e. the change in elevation or curvature of a plurality of continuous road segments
• CPC Class Codes: B60W 2552/30 Road curve radius
• CPC Class Codes: B60W 2554/4041 Position
• CPC Class Codes: B60W 30/16 Control of distance between vehicles, e.g. keeping a distance to preceding vehicle
• CPC Class Codes: B60W 30/18145 Cornering
• CPC Class Codes: B60W 30/18159 Traversing an intersection

Abstract

An electronic control unit of a motor vehicle is connected to signal transmitters and generates output signals in response to a desired speed signal, a yaw signal, a target vehicle signal, and a wheel speed signal. The electronic control unit generates a trigger signal that limits the momentary speed (or momentarily the acceleration) of the motor vehicle for at least a value that substantially corresponds to a maximum of a distance X between the motor vehicle and a target motor vehicle at the same time of its leaving the detection area. The distance X is reduced by a shortening stretch DX to an effective distance Xeff that is dependent on at least one of an environmental condition environment (motorway, country road, town traffic), the speed of the target motor vehicle at the time of leaving the detection area, the momentary speed of the motor vehicle, and the bend radii of bends already driven through in the past within a predetermined period of time.

Claims

1. A system for evaluating a traffic environment of a motor vehicle and for influencing a speed of the motor vehicle in its own traffic lane, comprising:

a signal transmitter that is configured to produce a signal characteristic of a desired speed of the motor vehicle;

a signal transmitter that is configured to produce a signal characteristic of a yaw of the motor vehicle about its vertical axis;

a signal transmitter that is configured to produce a signal characteristic of a target vehicle situated, in a direction of travel of the motor vehicle, in a detection area in front of the motor vehicle in terms of its spacing and orientation relative to the motor vehicle and that represents at least one of;

(i) a speed relative to the speed of the motor vehicle;

(ii) a spacing relative to the motor vehicle; and

(iii) an angular offset or the lateral drift relative to the vehicle longitudinal axis of the motor vehicle;

a signal transmitter that is configured to produce a signal characteristic of the speed of at least one wheel of the motor vehicle;

an electronic control unit (ECU) connected to the signal transmitters and that is configured to generate output signals in response to the desired speed signal, the yaw signal, the target vehicle signal, and the wheel speed signal in which in the electronic control unit (ECU) is configured to generate a trigger signal that limits the momentary speed or momentarily the acceleration of the motor vehicle for at least a value that substantially corresponds to a maximum of a distance X between the motor vehicle and the target motor vehicle at the time of its leaving the detection area, wherein the distance X is reduced by a shortening stretch DX to an effective distance X_eff that is dependent on at least one of an environmental condition environment (motorway, country road, town traffic), the speed of the target motor vehicle at the time of leaving the detection area, the momentary speed of the motor vehicle, and the bend radii of bends already driven through in the past within a predetermined period of time; and

a control device connected to the electronic control unit (ECU) and that is configured to influence the actual speed of the motor vehicle in response to the output signal and the trigger signal.

2. The system defined in claim 1 wherein the shortening stretch DX is determined from an average of the radii of bends already driven through in the past within a predetermined period of time.

3. The system defined in claim 1 wherein the trigger signal is characteristic of a maximum length of time resulting from the momentary speed of the motor vehicle and the distance X between the motor vehicle and the target motor vehicle at the time of its leaving the detection area or the effective distance X_eff.

4. The system defined in claim 1 wherein an object that is located in the detection area in front of the motor vehicle, goes below a predetermined distance, and is not located in the lane of the motor vehicle is excluded from selection as the target motor vehicle.

5. The system defined in claim 1 wherein an object that is located outside a predetermined angle to the central longitudinal axis of the motor vehicle or exceeds a predetermined angle is excluded from selection as the target motor vehicle.

6. The system defined in claim 1 wherein an object that has not been a target motor vehicle for a predetermined period of time in the past is excluded from the selection as the target motor vehicle.

7. The system defined in claim 1 wherein objects that have not been target motor vehicles for a predetermined period of time in the past are excluded from the selection as the target motor vehicle.