Device and method for controlling the vehicle speed of a vehicle by means of an ACC system

Abstract

ACC system (1) for controlling the speed of a vehicle, which is kept active even when the driver detects the application of the vehicle brake (2), if a critical approach of the vehicle to another object in front of it is detected by a proximity detection unit (3) of the ACC system (1).

Description

[0001] The invention relates to a method and a device for controlling the vehicle speed of a vehicle, in particular a road vehicle, by means of an Adaptive Cruise Control (ACC) system.

[0002] Motor vehicles are increasingly being equipped with adaptive cruise control systems.

[0003] In an ACC system, the position and speed of a vehicle ahead are determined by an ACC sensor unit, and the speed and distance of the following vehicle equipped with the ACC system are adaptively regulated accordingly by engine and / or brake intervention. Conventional vehicles primarily use radar sensors for distance measurement. LiDAR systems are also used. ACC systems increase driving comfort and reduce driver concentration on long journeys, especially on highways. Furthermore, the ACC system enhances driving safety.

[0004] Conventional adaptive cruise control (ACC) systems are deactivated by the driver briefly applying the vehicle's brakes. The driver taps the brake pedal briefly to deactivate the ACC system. This behavior is familiar from traditional adaptive cruise control systems and serves a safety purpose, as it prevents the vehicle from unintentionally accelerating after braking. Drivers also frequently use this function to deactivate the cruise control or ACC system by briefly tapping the brake pedal without having to take their hands off the steering wheel. Therefore, this additional deactivation option is generally desirable.

[0005] In a vehicle equipped with a conventional ACC system, and especially with relatively inexperienced drivers, it can happen that, at high relative speeds to a vehicle ahead, the driver is unsure whether the deceleration provided by the ACC system is sufficient to prevent a collision. If, in this traffic situation, the driver taps the brake pedal out of uncertainty or applies insufficient pressure, the ACC system will be deactivated during this critical situation, and active deceleration by the vehicle's braking system will be either canceled or reduced to a lower level requested by the driver.Unlike a conventional cruise control system, deactivating the ACC system therefore creates a critical traffic situation, which in the worst case can lead to the vehicle colliding with the vehicle in front.

[0006] It is therefore an object of the present invention to create an ACC system for controlling the driving speed of a vehicle, in which such a critical traffic situation is reliably avoided and thus the safety when driving the vehicle is increased.

[0007] This problem is solved according to the invention by an ACC system with the features specified in claim 1.

[0008] According to a first aspect, the invention therefore provides an ACC system for controlling the driving speed of a vehicle, which is kept active even when the driver detects that the vehicle brakes have been applied, if a critical approach of the vehicle to another object in front of it is detected by a proximity detection unit of the ACC system.

[0009] Possible embodiments of the ACC system according to the invention are specified in the dependent claims.

[0010] In one possible embodiment of the ACC system according to the invention, the proximity detection unit recognizes a critical approach of the vehicle to the object in front of it based on predefined programmable proximity criteria.

[0011] In another possible embodiment of the ACC system according to the invention, the ACC system has an ACC sensor unit that detects objects located in front of the vehicle, in particular other vehicles, within a field of view of the ACC sensor unit.

[0012] In another possible embodiment of the ACC system according to the invention, a first approach criterion is the presence or entry of an object into the field of view of the ACC sensor unit.

[0013] In another possible embodiment of the ACC system according to the invention, a second approach criterion is a reduction of the distance between an object located in front of the vehicle and the vehicle itself.

[0014] In another possible embodiment of the ACC system according to the invention, a third approach criterion is a reduction of a time gap between an object located in front of the vehicle and the vehicle.

[0015] In another possible embodiment of the ACC system according to the invention, when the driver activates the vehicle brake, the proximity detection unit of the ACC system checks whether the vehicle is approaching another object in front of it at a critical distance, and if a critical distance is detected, the ACC system is kept active, and if no critical distance is detected, the ACC system is either deactivated immediately or an analysis unit of the ACC system first checks, based on the activation of the vehicle brake, whether this activation of the vehicle brake was intentionally carried out by the driver to deactivate the ACC system.

[0016] In another possible embodiment of the ACC system according to the invention, the ACC system is kept active if the analysis unit of the ACC system detects, based on the actuation of the vehicle brake, that this actuation of the vehicle brake was not carried out by the driver to deactivate the ACC system.

[0017] In another possible embodiment of the ACC system according to the invention, the ACC system is deactivated if the analysis unit of the ACC system recognizes, based on the actuation of the vehicle brake, that this actuation of the vehicle brake by the driver was actually carried out to deactivate the ACC system.

[0018] In another possible embodiment of the ACC system according to the invention, the analysis unit evaluates a brake pressure curve caused by the actuation of the vehicle brake in order to recognize whether this actuation of the vehicle brake by the driver was intentionally carried out to deactivate the ACC system.

[0019] In another possible embodiment of the ACC system according to the invention, the driver receives an acoustic or visual message if the ACC system is kept active despite the driver applying the vehicle brakes, due to the detected critical approach of the vehicle to another object in front of it or due to another reason, in particular a detected uncertainty of the driver.

[0020] The invention further provides a method for controlling the vehicle speed of a vehicle by means of an ACC system with the features specified in claim 12.

[0021] The invention therefore provides a method for controlling the vehicle speed of a vehicle by means of an ACC system, wherein the ACC system is kept active even when the driver has detected an application of the vehicle brake, if a critical approach of the vehicle to another object located in front of it is detected by a proximity detection unit of the ACC system.

[0022] Possible embodiments of the method according to the invention are specified in the dependent claims.

[0023] In one possible embodiment of the method according to the invention, a critical approach of the vehicle is detected based on predetermined approach criteria.

[0024] In another possible embodiment of the method according to the invention, when the vehicle brake is activated by the driver, it is checked whether the vehicle is approaching another object in front of it at a critical distance, and if a critical distance is detected, the ACC system is kept active, and if no critical distance is detected, the ACC system is either deactivated immediately or, based on the activation of the vehicle brake, it is first checked whether this activation was intentionally carried out by the driver to deactivate the ACC system.

[0025] In another possible embodiment of the method according to the invention, the ACC system is kept active if it is recognized, based on the actuation of the vehicle brake, that this actuation is not being carried out to deactivate the ACC system, and the ACC system is deactivated if it is recognized, based on the actuation of the vehicle brake, that this actuation of the vehicle brake was intentionally carried out by the driver to deactivate the ACC system.

[0026] According to a further aspect, the invention provides a vehicle, in particular a road vehicle, with an ACC system for controlling the vehicle's speed, wherein the vehicle's ACC system is kept active even when the driver detects that the vehicle's brakes have been applied, if a critical approach of the vehicle to another object in front of it, in particular another vehicle, is detected by a proximity detection unit of the vehicle's ACC system.

[0027] Possible embodiments of the ACC system according to the invention and the method according to the invention for controlling the vehicle speed of a vehicle by means of an ACC system are explained in more detail below with reference to the attached figures.

[0028] They show:

[0029] Fig. 1 a block diagram illustrating an embodiment of an ACC system according to the invention for controlling the driving speed of a vehicle;

[0030] Fig. 2 a flowchart illustrating an embodiment of the inventive method for controlling the vehicle speed of a vehicle by means of an ACC system;

[0031] Fig. 3 a further flowchart to illustrate a further embodiment of the inventive method for controlling the vehicle speed of a vehicle by means of an ACC system.

[0032] How to turn a block diagram into Fig. 1 can be recognized, an ACC system according to the invention has 1 The illustrated embodiment contains several components. Fig. 1 ACC system shown 1It is located in a vehicle, particularly a road vehicle, such as a car, truck, or motorcycle. The ACC system 1 It is used to regulate the vehicle's speed. The ACC system 1 is connected to the vehicle brake 2 the vehicle is connected. The ACC system can be used in this process. 1 the actuation of the vehicle brake pedal 2 detect. After the vehicle brakes have been activated, it is recognized. 2 The ACC system is controlled by the driver. 1 kept active if a proximity detection unit detects a critical approach of the vehicle to another object in front of it. 3 of the ACC system 1 is detected. The ACC system 1 has at least one ACC sensor unit 4 The ACC sensor unit detects objects in front of the vehicle, especially other vehicles, within its field of view. 4One possible embodiment features radar sensors. Furthermore, the ACC sensor unit can 4 One possible embodiment includes a so-called LIDAR unit. The ACC sensor unit 4 It is preferably located at the front of the vehicle and detects objects located in front of the vehicle within a field of view of the ACC sensor unit. 4 The viewing area has an opening angle that depends on the type of ACC sensor unit. 4 depends.

[0033] The proximity detection unit 3 It detects a critical approach of the vehicle to a moving or stationary object in front of it based on predefined, programmable approach criteria. In one possible embodiment, a first approach criterion is the presence or entry of an object into the field of view of the ACC sensor unit. 4 For example, if a vehicle equipped with the ACC system is moving1 according to Fig. One equipped vehicle is in the left lane of a motorway and shears another vehicle from the right lane of the motorway into the left lane within the field of view of the ACC sensor unit. 4 For example, if a vehicle moves to avoid a slower truck driving in front of it in the right lane, this constitutes a first approach criterion for the approach detection unit. 3 Another possible approach criterion is a reduction in the distance between an object in front of the vehicle and the object equipped with the ACC system. 1 A third approach criterion is a reduction in the time gap between an object in front of the vehicle and the object equipped with the ACC system. 1 This represents a vehicle equipped with the ACC system. A target distance is calculated as the product of the time gap and the vehicle's own speed or driving speed. 1equipped vehicle. In another possible embodiment, further or different proximity criteria can be determined by the proximity detection unit. 3 be used.

[0034] After the vehicle brakes have been activated, it has been detected. 2 by the driver of the vehicle through the proximity detection unit 3 In one possible embodiment of the ACC system according to the invention, 1 First, it is checked whether the vehicle is approaching another object in front of it at a critical distance. If, based on the approach criteria, a critical distance is detected by the proximity detection unit... 3 When detected, the ACC system will be activated. 1 kept active, whereas if no critical approach is detected, the ACC system 1 either deactivated immediately or by an analysis unit 5 of the ACC system 1The activation of the vehicle brake is first checked to determine whether this activation of the vehicle brake is successful. 2 intentionally deactivated by the driver to activate the ACC system 1 was carried out. The ACC system 1 It will then be kept active if, based on the application of the vehicle brakes, 2 through the analysis unit 5 of the ACC system 1 It is recognized that the vehicle brake has been applied. 2 not for deactivating the ACC system 1 was carried out. In contrast, the ACC system 1 deactivated if indicated by the vehicle brake being applied 2 through the analysis unit 5 of the ACC system 1 It is recognized that this actuation of the vehicle brake 2 intentionally deactivated by the driver to activate the ACC system 1 was done.

[0035] In one possible embodiment of the ACC system according to the invention1 evaluates the analysis unit 5 one by applying the vehicle brake 2 The resulting brake pressure curve is analyzed to determine whether the vehicle brakes have been applied. 2 intentionally deactivated by the driver to activate the ACC system 1 was carried out. For this purpose, the analysis unit 5 preferably connected to a brake pressure line of a brake hydraulic system and measures the pressure generated by the actuation of the vehicle brake 2 brake pressure profile caused in the brake pressure line.

[0036] In one possible embodiment, the driver receives acoustic or visual feedback when the ACC system 1 despite the vehicle brakes being applied 2 by which it is nevertheless kept active due to the critical approach of the vehicle to another object located in front of it or for any other recognized reason, for example, a recognized uncertainty of the driver.

[0037] Fig. Figure 2 shows a flowchart illustrating a possible embodiment of the inventive method for controlling the vehicle speed of a vehicle by means of an ACC system. 1 , especially through the in Fig. 1 ACC system shown 1 .

[0038] The ACC system 1 This also applies when the vehicle brakes are detected to be applied. 2 kept active by the driver in case the proximity detection unit detects a critical approach of the vehicle to another object in front of it. 3 of the ACC system 1 is detected. After a start in step S0, it is first checked in step S1 whether the vehicle brake is functioning. 2 has been activated. For example, an electrical contact provided on the brake pedal can send a signal to the ACC system. 1 to provide information on whether the vehicle brakes 2was activated by the driver.

[0039] As soon as the vehicle brakes are applied 2 Once detected, the proximity detection unit will process the information in step S2. 3 The system checks whether a critical approach has occurred. This is preferably done using predefined, programmable approach criteria. In one possible embodiment, a first approach criterion is the presence or entry of an object into the field of view of the ACC sensor unit. 4 Another approach criterion is a reduction in the distance between an object in front of the vehicle and the object equipped with the ACC system. 1 A third approach criterion in one possible embodiment is a time gap between an object located in front of the vehicle and the object equipped with the ACC system. 1 equipped vehicle.

[0040] At the in Fig. In the embodiment shown in step 2, the ACC system is activated in step S3. 1 The system remains active if a critical approach is present. Conversely, if step S2 detects that no critical approach is present, the ACC system is deactivated. 1 deactivated in step S4.

[0041] Fig. Figure 3 shows a further embodiment of the method according to the invention. In the Fig. In the embodiment shown in 3, it is also checked in step S1 whether a vehicle brake 2 has been activated by the driver. If this is the case, step S2 continues to check whether there is a critical approach to a moving object or vehicle ahead. If this is not the case, the following occurs: Fig. In step S5 of the exemplary embodiment shown in section 3, it was further checked whether a deliberate deactivation of the ACC system had occurred. 1 is present. If this is not the case, the ACC system is activated in step S3. 1If, conversely, step S5 detects that the ACC system has been intentionally deactivated, it remains active. 1 If the driver is involved, the ACC system will be activated in step S4. 1 deactivated.

[0042] In the Fig. 2, Fig. The ACC system is shown in the 3 illustrated embodiments. 1 the vehicle was kept actively engaged, even though the driver had applied the vehicle brakes. 2 has activated. If the ACC system 1 despite the vehicle brakes being applied 2 by the driver due to a detected critical approach of the vehicle or any other reason, in particular one detected by the analysis unit 5 If the driver's uncertainty in the traffic situation is detected and actively maintained, the driver preferably receives additional acoustic and visual feedback.

[0043] In one possible embodiment of the method according to the invention, a distinction can be made between a deliberate deactivation of the ACC system based on the data supplied by environmental and vehicle sensors. 1 by tapping the vehicle brake 2 and a braking maneuver by an unsafe driver, in order to prevent a critical situation by deactivating or shutting down the ACC. The vehicle ahead, detected by the vehicle's environmental sensors, can serve as a decision criterion. If the ACC system is to be deactivated... 1 By tapping the vehicle brake, the area in front of the vehicle equipped with the ACC system is cleared. 1The equipped vehicle is usually free, for example when approaching an exit or reducing vehicle speed due to a speed limit, or only slight decelerations are necessary which are in the range of engine drag torque, i.e. there is a smooth approach to a slower vehicle ahead, which is controlled by the ACC system. 1 This would not be carried out in this way. Another criterion for recognizing an intentional deactivation of the ACC system is... 1 The length and strength of the brake application can be used, since in this situation the driver does not want deceleration, but only the activation of the brake light switch.

[0044] If the vehicle brakes are applied while approaching a vehicle ahead at high relative speed, the ACC system will not deactivate as intended. 1It's not a risk, but rather a driver uncertainty. In this situation, the ACC system remains inactive. 1 The system is active and delays by at least the calculated necessary delay. Additionally, the driver may receive confirmation that the ACC system has responded to this situation. 1 This was detected in order to eliminate or reduce driver uncertainty. In another possible embodiment, the system also adjusts the deceleration profile, for example by slightly increasing the braking deceleration.

[0045] With the ACC system according to the invention 1 Critical situations are caused by an unintentional deactivation of the ACC system. 1Particularly when driver uncertainty is detected, the system avoids unwanted deactivation by distinguishing between a desired shutdown and an undesired shutdown caused by braking. Providing feedback to the driver about the detected situation further increases confidence in the system. The signals are evaluated in the ACC system according to the invention. 1 preferably in real time. In one possible embodiment, this is done according to the embodiments described above. Fig. 2, Fig. The methods described in section 3 are executed by one or more microprocessors via a corresponding control program. In some embodiments, the approach criteria can be programmed via an interface.

Claims

[1] ACC system ( 1 ) to regulate the speed of a vehicle, even when the vehicle brakes have been activated ( 2 ) is kept active by the driver in case a critical approach of the vehicle to another object in front of it is detected by a proximity detection unit ( 3 ) of the ACC system ( 1 ) is recognized. [2] ACC system according to claim 1, wherein the proximity detection unit ( 3 ) detects a critical approach of the vehicle to the object in front of it based on predefined programmable approach criteria. [3] ACC system according to claim 1 or 2, wherein the ACC system ( 1 ) an ACC sensor unit ( 4 ) exhibits objects located in front of the vehicle, in particular other vehicles, within a field of view of the ACC sensor unit ( 4 ) recorded. [4] ACC system according to claim 3, wherein a first approach criterion is the presence or entry of an object into the field of view of the ACC sensor unit ( 4 ) is. [5] ACC system according to claim 3, wherein a second approach criterion is a reduction of a distance between an object located in front of the vehicle and the vehicle. [6] ACC system according to claim 4 or 5, wherein a third approach criterion is a reduction of a time gap between an object located in front of the vehicle and the vehicle. [7] ACC system according to any one of the preceding claims 1 to 6, wherein, upon detection of application of the vehicle brake ( 2 ) by the driver through the proximity detection unit ( 3 ) of the ACC system ( 1 ) checks whether the vehicle is approaching another object in front of it at a critical distance, and if a critical distance is detected, the ACC system (1 ) is kept active, whereby, if no critical approach is detected, the ACC system ( 1 ) is either deactivated immediately or by an analysis unit ( 5 ) of the ACC system ( 1 ) based on the application of the vehicle brakes ( 2 ) first checks whether this activation of the vehicle brake ( 2 ) by the driver to deactivate the ACC system ( 1 ) was carried out. [8] ACC system according to claim 7, wherein the ACC system ( 1 ) is kept active if, based on the application of the vehicle brake ( 2 ) by the analysis unit ( 5 ) of the ACC system ( 1 ) is recognized as an actuation of the vehicle brake ( 2 ) not to deactivate the ACC system ( 1 ) was carried out. [9] ACC system according to claim 7 or 8, wherein the ACC system ( 1 ) is deactivated if the vehicle brake is activated ( 2) by the analysis unit ( 5 ) of the ACC system ( 1 ) is recognized as an actuation of the vehicle brake ( 2 ) by the driver to deactivate the ACC system ( 1 ) was carried out. [10] ACC system according to claim 9, wherein the analysis unit ( 5 ) one by applying the vehicle brake ( 2 ) evaluates the resulting brake pressure curve to determine whether the vehicle brake has been actuated ( 2 ) intentionally deactivated by the driver ( 1 ) was carried out. [11] ACC system according to any one of the preceding claims 1 to 9, wherein the driver receives an acoustic or visual message when the ACC system ( 1 ) despite the vehicle brake being applied ( 2) is actively maintained by the driver due to the vehicle's perceived critical approach to another object in front of it or due to a perceived uncertainty on the part of the driver. [12] Method for controlling the vehicle speed of a vehicle by means of an ACC system ( 1 ), where the ACC system ( 1 ) even when a vehicle brake has been activated ( 2 ) is kept active by the driver in case a critical approach of the vehicle to another object in front of it is detected by a proximity detection unit ( 3 ) of the ACC system ( 1 ) is recognized. [13] Method according to claim 12, wherein a critical approach of the vehicle is detected based on predetermined approach criteria. [14] Method according to claim 12 or 13, wherein, upon detection of activation of the vehicle brake ( 2) the driver checks whether the vehicle is approaching another object in front of it at a critical distance, and if a critical distance is detected, the ACC system ( 1 ) is held, whereby, if no critical approach is detected, the ACC system ( 1 ) is either deactivated immediately or based on the application of the vehicle brakes ( 2 ) first, it is checked whether this action is intended by the driver to deactivate the ACC system ( 1 ) was carried out. [15] Method according to claim 14, where the ACC system ( 1 ) is kept active if, based on the application of the vehicle brake ( 2 ) it is recognized that this action is not for deactivating the ACC system ( 1 ) was carried out, where the ACC system ( 1 ) is deactivated if the vehicle brake is activated ( 2) is recognized that this action by the driver is intended to deactivate the ACC system ( 1 ) was carried out.

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