Electronically Controlled Cruise Control System for Motor Vehicles

Abstract

An electronically controlled cruise control system for motor vehicles, in which during a first closed-loop control operation the vehicle speed is set to a predetermined speed and/or during a second closed-loop control operation, whilst a desired distance from a vehicle in front is maintained, the speed is subjected to open- or closed-loop control, and, in order to reach and/or maintain the predetermined speed and/or the desired distance from the vehicle in front, a maximum acceleration of the vehicle is permitted. The maximum permitted acceleration is predetermined in accordance with a presence signal from a presence detection system of a trailer coupling attached to the vehicle.

Claims

1.-11. (canceled)

12. An electronically controlled cruise control system for a motor vehicle, in which during a first closed-loop control operation, a vehicle speed is open-loop or closed-loop controlled to a specified speed, wherein a maximum permitted acceleration of the motor vehicle is permitted to achieve and/or maintain the specified speed, wherein the maximum permitted acceleration is determined based on an occupancy signal of an occupancy detection of a trailer hitch attached to the motor vehicle.

13. An electronically controlled cruise control system for a motor vehicle, in which during a second closed-loop control operation, a vehicle speed is open-loop or close-loop controlled while maintaining a desired distance to a vehicle in front, wherein a maximum permitted acceleration of the motor vehicle is permitted to achieve and/or maintain the desired distance to the vehicle in front, wherein the maximum permitted acceleration is determined based on an occupancy signal of an occupancy detection of a trailer hitch attached to the motor vehicle.

14. The electronically controlled cruise control system according to claim 12, wherein upon receipt of an existing occupancy signal of the occupancy detection, a lower maximum acceleration is permitted than upon receipt of a non-existing occupancy signal of the occupancy detection.

15. The electronically controlled cruise control system according to claim 13, wherein upon receipt of an existing occupancy signal of the occupancy detection, a lower maximum acceleration is permitted than upon receipt of a non-existing occupancy signal of the occupancy detection.

16. The electronically controlled cruise control system according to claim 12, wherein the maximum permitted acceleration upon receipt of an existing occupancy signal of the occupancy detection is determined based on at least one other parameter including a current vehicle speed and/or a difference between the current vehicle speed and the specified speed to be achieved.

17. The electronically controlled cruise control system according to claim 13, wherein the maximum permitted acceleration upon receipt of an existing occupancy signal of the occupancy detection is determined based on at least one other parameter including a current vehicle speed and/or a difference between the current vehicle speed and the specified speed to be achieved.

18. The electronically controlled cruise control system according to claim 12, wherein the maximum permitted acceleration upon receipt of an existing occupancy signal of the occupancy detection is determined based on speed-dependent acceleration values of a stored characteristic curve for the maximum permitted acceleration.

19. The electronically controlled cruise control system according to claim 13, wherein the maximum permitted acceleration upon receipt of an existing occupancy signal of the occupancy detection is determined based on speed-dependent acceleration values of a stored characteristic curve for the maximum permitted acceleration.

20. The electronically controlled cruise control system according to claim 12, wherein the maximum permitted acceleration upon receipt of an existing occupancy signal of the occupancy detection is determined based on a result of a difference of the maximum permitted acceleration upon receipt of a non-existing occupancy signal of the occupancy detection and a specified offset value.

21. The electronically controlled cruise control system according to claim 13, wherein the maximum permitted acceleration upon receipt of an existing occupancy signal of the occupancy detection is determined based on a result of a difference of the maximum permitted acceleration upon receipt of a non-existing occupancy signal of the occupancy detection and a specified offset value.

22. The electronically controlled cruise control system according to claim 12, wherein the occupancy detection is configured to generate the occupancy signal by evaluating an occupancy of a plug connection associated with the trailer hitch.

23. The electronically controlled cruise control system according to claim 13, wherein the occupancy detection is configured to generate the occupancy signal by evaluating an occupancy of a plug connection associated with the trailer hitch.

24. The electronically controlled cruise control system according to claim 12, wherein the occupancy detection is configured to generate the occupancy signal by evaluating an occupancy of a plug connection associated with the trailer hitch and evaluating at least one other parameter.

25. The electronically controlled cruise control system according to claim 13, wherein the occupancy detection is configured to generate the occupancy signal by evaluating an occupancy of a plug connection associated with the trailer hitch and evaluating at least one other parameter.

26. A method for controlling an electronically controlled cruise control system for a motor vehicle, wherein during a first closed-loop control operation, a speed is fundamentally open-loop or closed-loop controlled to a specified speed and only a maximum permitted acceleration of the motor vehicle is permitted to achieve and/or maintain the specified speed, wherein the maximum permitted acceleration is determined based on an occupancy signal of an occupancy detection of a trailer hitch attached to the motor vehicle.

27. A method for controlling an electronically controlled cruise control system for a motor vehicle, wherein during a second closed-loop control operation, a speed is open-loop or closed-loop controlled while maintaining a desired distance to a vehicle in front and only a maximum permitted acceleration of the motor vehicle is permitted to achieve and/or maintain a desired distance to the vehicle in front, wherein the maximum permitted acceleration is determined based on an occupancy signal of an occupancy detection of a trailer hitch attached to the motor vehicle.

28. A vehicle having an electronically controlled cruise control system for motor vehicles according to claim 12.

29. A vehicle having an electronically controlled cruise control system according to claim 13.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG. 1 shows an exemplary structure of an electronically controlled cruise control system according to the invention.

[0029] FIG. 2 shows a simplified flow chart for a method according to the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[0030] FIG. 1 shows an electronically controlled cruise control system F having a control unit SE, which closed-loop controls the vehicle speed v to a specified speed during a first closed-loop control operation (ACC free driving) by means of a first controller unit R1. In addition, the control unit comprises a second controller unit R2, which open-loop or closed-loop controls the speed to maintain a minimum distance to a vehicle in front, at latest, upon reaching or falling below a specified minimum distance during a second closed-loop control operation (ACC following driving). To achieve and/or maintain the specified speed and/or the specified minimum distance, the control unit SE causes acceleration or deceleration of the vehicle by outputting an acceleration value a, in that corresponding actuators Ak (e.g., engine, clutch, brake) are actuated based on the acceleration value a.

[0031] To detect relevant items of surroundings information, in particular relevant vehicles in front, the control unit SE receives sensor signals s from one or more surroundings sensors S monitoring and/or analyzing the surroundings.

[0032] Furthermore, the control unit SE receives a speed signal v and an occupancy signal 0 or 1 of an occupancy detection BE for a trailer hitch A attached to the vehicle, which comprises a plug connection ST in addition to the hitch device K. For the occupancy detection of the trailer hitch A, it is evaluated whether the plug connection ST is occupied, i.e., a plug is connected to the plug connection ST. If a plug occupancy is detected, the occupancy detection BE sends a signal 1 to the control unit SE, otherwise no signal or a signal 0.

[0033] Furthermore, the control unit SE is connected to a storage unit SP, wherein multiple speed-dependent characteristic curves for a maximum permitted acceleration are stored in the storage unit for consideration in the cruise controls. Thus, for example, a speed-dependent characteristic curve KL is stored in each case for the maximum permitted acceleration for a detected driving operation of the vehicle without trailer and with trailer.

[0034] Finally, the control unit SE is configured, for the cruise control during the first closed-loop control operation and/or during the second closed-loop control operation for the open-loop cruise control or closed-loop cruise control based on the acceleration limiting values stored in the characteristic curves KL, to specify or select the respective suitable maximum permitted acceleration (e.g., amax1 or amax2) in dependence on the occupancy signal 0 or 1 of the occupancy detection BE of the trailer hitch A attached to the vehicle and to take it into consideration accordingly in the closed-loop control.

[0035] In particular, it can be provided here that upon detected occupancy of the trailer hitch, an identical maximum permitted acceleration or different maximum permitted accelerations are specified for both controller units R1 and R2. Alternatively, individual characteristic curves having speed-dependent maximum permitted acceleration values can each be stored both for the occupancy state of the trailer hitch A and for each controller unit R1 and R2 and according to the conditions (controller unit 1 or 2 active, trailer detected or not), the relevant speed-dependent value for the maximum permitted acceleration can be determined and specified from the applicable characteristic curve.

[0036] A design of the method according to the invention will be explained in more detail on the basis of FIG. 2.

[0037] The method begins in step 10, as soon as a cruise control system ACC is active. If this is the case, it is checked in the next step 20 whether a trailer hitch A attached to the vehicle is occupied.

[0038] If an occupied trailer hitch A is not detected, the sequence passes to step 30. In consideration of the current speed v, the specified speed, and possibly in consideration of the distance to a target object in front, a maximum permitted acceleration amax1 is specified there for the closed-loop control, which is taken into consideration in the next step 40 in the cruise control.

[0039] If an occupied trailer hitch A is detected in step 20, the sequence passes to step 50. In consideration of the current speed v, the specified speed, and possibly in consideration of the distance to a target object in front, a maximum permitted acceleration amax2 reduced for the closed-loop control is specified there, which is less than the maximum permitted acceleration amax1. In the next step 60, the cruise control takes place in consideration of this reduced maximum acceleration amax2. The maximum permitted acceleration amax2 upon detected trailer hitch occupancy is specified or reduced in relation to the maximum permitted acceleration amax1 enough that a comfortable acceleration level with attached trailer is or will be achieved for the driver.