Deactivating an automatic braking function of an automatic collision avoidance system for collision avoidance when parking or maneuvering

Abstract

Method for deactivating an automatic braking function of an automatic collision avoidance system for collision avoidance when parking or maneuvering a motor vehicle, comprising the following steps: - Detect (110) a depressing of the brake pedal up to a specified brake pedal threshold (BP) TH ) a characteristic value for depressing the brake pedal or above the specified brake pedal threshold (BP) TH ) out; - in response to this, deactivating (120) the automatic braking function of the automatic collision avoidance system; - after deactivating the automatic braking function, determine (130) that one or more conditions for reactivating the automatic braking function are met; and - in response to this, automatic reversal (140) of the deactivation of the automatic braking function.

Description

[0001] The invention relates to an automatic collision avoidance system for avoiding collisions when parking or maneuvering with an automatic braking function, in particular the invention relates to the deactivation of the automatic braking function.

[0002] With automated lateral guidance parking systems, the system automatically steers the vehicle during the parking maneuver, guiding it into a parking space. The driver must maintain longitudinal control by accelerating and braking as needed. In systems with both automated lateral and longitudinal guidance, the system also handles longitudinal control. However, in many parking or maneuvering situations, such systems with automatic lateral and optional longitudinal guidance are not suitable, and the driver must maneuver the vehicle manually. In these situations, the driver can use an ultrasonic parking aid with acoustic and / or visual obstacle warnings, or a camera-based system, such as a reversing camera or a multi-camera system providing a top-down view of the vehicle's surroundings.

[0003] Furthermore, automatic collision avoidance systems with automatic braking intervention are known for preventing collisions during manual parking or maneuvering at low speeds (e.g., v < 10 km / h). These systems use environmental sensors, such as ultrasonic sensors and / or a laser scanner, to detect obstacles in the vehicle's surroundings. To avoid a collision with a detected obstacle, the collision avoidance system can intervene by braking the vehicle, in particular to a standstill. Steering intervention can also be included as an option.

[0004] Such automatic collision avoidance systems of the applicant are described in the publication “Automatic Collision Avoidance during Parking and Maneuvering - an Optimal Control Approach”, B. Gutjahr and M. Werling, Intelligent Vehicles Symposium Proceedings 2014, pages 636 - 641, IEEE.

[0005] Such automatic collision avoidance systems are typically designed rather conservatively due to sensor noise from the environmental sensors (especially regarding the vehicle's sides, which are easily judged by the driver but difficult for the sensors to see), meaning they tend to brake too early rather than too late. Therefore, in certain maneuvering situations where the driver wants to move the vehicle closer to an obstacle than the system allows, an automatic braking intervention may be triggered that is not readily apparent to the driver. This can occur, for example, if the driver wants to pass an obstacle very closely from the side.In such situations, where the driver wants to move the vehicle closer to an obstacle than the system allows, and therefore the system triggers an unwanted braking intervention, the vehicle can be manually maneuvered without disruptive intervention from the collision avoidance system (for example, to pass very close to an obstacle from the side), there is a need for an intuitive, driver-activated deactivation mechanism for the automatic braking function.

[0006] Another automatic collision avoidance system is described in German patent application DE 10 2009 029 456 A1. In this system, if the driver only lightly presses the brake pedal, the system overrides the deceleration signal sent via the brake pedal to bring the vehicle to a stop in time before a collision object. To give the driver full control of the vehicle, this override of the driver's braking signal must be deactivated. In this document, deactivation is achieved by the driver releasing the brake pedal. This method has the disadvantage that the driver is forced to release the brake pedal, preventing them from keeping their foot on the brake pedal to counteract the creeping torque of a clutched automatic transmission when the brake is lightly applied.For example, the driver cannot crawl into a tight parking space with the brake pedal lightly applied.

[0007] German patent application DE 10 2005 038 489 A1 describes a method for deactivating an automatic start-up function of a distance-based cruise control system. In this method, the cruise control system maintains a distance based on a detected target object, and the vehicle is kept stationary because the target object is stationary. The automatic start-up function is automatically deactivated when a moving object is detected between the stationary target object and the vehicle. To deactivate the automatic start-up function, the entire distance-based cruise control system can be deactivated.To prevent the vehicle from unintentionally rolling after the adaptive cruise control system is deactivated, an automatically activated braking function keeps the vehicle stationary. The automatically activated brake is only released when the driver operates a designated control, such as the brake pedal.

[0008] The object of the invention is to provide an improved, intuitive deactivation method for deactivating an automatic braking function of an automatic collision avoidance system for parking or maneuvering and a corresponding automatic collision avoidance system.

[0009] The problem is solved by the features of the independent claims. Advantageous embodiments are described in the dependent claims.

[0010] A first aspect concerns a method for deactivating an automatic braking function of an automatic collision avoidance system for collision avoidance when parking or maneuvering a motor vehicle according to claim 1. The vehicle is preferably a vehicle with an automatic transmission, wherein the automatic transmission generates a creep torque to drive the vehicle when the accelerator pedal is not depressed.

[0011] Deactivating the automatic braking function renders the braking function ineffective.

[0012] The collision avoidance system is, for example, an automatic collision avoidance system as described in the publication "Automatic Collision Avoidance during Parking and Maneuvering - an Optimal Control Approach," B. Gutjahr and M. Werling, Intelligent Vehicles Symposium Proceedings 2014, pages 636-641, IEEE. The disclosure of this publication regarding the collision avoidance systems described therein is hereby incorporated into the disclosure of this application by reference.

[0013] In the method according to the invention, it is determined that the brake pedal is depressed up to a certain brake pedal threshold (BP). TH) or is depressed beyond a specific brake pedal threshold. The brake pedal threshold corresponds to a threshold value of a quantity characteristic of brake pedal depression. It is determined whether the quantity characteristic of brake pedal depression reaches or exceeds the brake pedal threshold.

[0014] The threshold is chosen, for example, so that the brake pressure of the service brake is sufficient to bring the vehicle to a safe stop when the threshold is reached or exceeded. In one embodiment of the method, it may be sufficient for the driver to depress the brake pedal down to the threshold to deactivate the braking function. In an alternative embodiment of the method, it is necessary for the driver to depress the brake pedal beyond the threshold to deactivate the braking function.

[0015] The brake pedal deflection and the quantity characteristic for depressing the brake pedal include, for example, brake pedal travel, pedal force, brake pressure, brake torque, or a combination of several of these quantities.

[0016] In response to the detection that the brake pedal has been depressed up to or beyond the specified brake pedal threshold, the automatic braking function of the automatic collision avoidance system is deactivated.

[0017] The ability to deactivate the braking function by pressing the brake pedal down to or beyond a certain threshold is intuitive for the driver and allows the driver, after deactivating the braking function, to move the vehicle into a tight parking space, for example, with the brake pedal lightly depressed in creep mode (i.e., with the vehicle driven by a creeping torque of the engaged automatic transmission), without disruptive automatic braking intervention.

[0018] Deactivating the automatic braking function can apply to the entire monitored vehicle environment, meaning that the system will no longer trigger any automatic braking intervention when the braking function is deactivated. Alternatively, it can be configured that deactivating the braking function only affects the specific obstacle that previously triggered the automatic braking intervention. After deactivation, the driver can then, for example, manually drive very close to this obstacle without triggering a braking intervention due to that obstacle; a braking intervention due to a different obstacle would still be possible despite the deactivation.

[0019] In addition to the braking function, one or more other functions of the collision avoidance system can also be deactivated, such as steering intervention to prevent a collision or an audible warning. The entire collision avoidance system can be completely deactivated.

[0020] It is designed that the deactivation of the braking function before the engine is switched off will also be automatically reversed, without the driver having to manually activate the automatic braking function (for example, by pressing a button). After the automatic braking function is deactivated, it is detected that one or more conditions for reactivating the deactivation are met, and in response, the deactivation of the automatic braking function is automatically reversed, i.e., the automatic braking function is reactivated, so that the vehicle is subsequently protected by the automatic collision protection system again.

[0021] It may be designed so that, before deactivating the automatic braking function, the automatic collision avoidance system first initiates an automatic braking intervention to avoid a collision with a specific obstacle, thus braking the vehicle to a standstill. Then, while the vehicle is stationary, the system detects that the brake pedal has been pressed down to or beyond a certain threshold. In response, the automatic braking function is deactivated. Therefore, to deactivate the braking function, the driver can briefly press the brake pedal above a specific predefined threshold while the vehicle is stationary.

[0022] It is possible that the driver lightly depresses the brake pedal immediately before an automatic braking intervention is triggered (but the brake pedal threshold is not reached). Alternatively, the driver may not depress the brake pedal immediately before the automatic braking intervention is triggered. In the first case, after the vehicle has decelerated due to the automatic braking intervention, the driver will depress the brake pedal more firmly to deactivate the automatic braking function, so that the brake pedal position reaches or exceeds the threshold, thus triggering deactivation of the automatic braking function. In the second case, after the vehicle has decelerated due to the automatic braking intervention, the driver will depress the brake pedal, which was previously not pressed, so that the brake pedal position reaches or exceeds the threshold, thus triggering deactivation of the braking function.

[0023] The automatic reactivation of the automatic braking function may be particularly useful in cases where the automatic collision avoidance system has already initiated automatic braking intervention to prevent a collision in a tight maneuvering situation before the automatic braking function is deactivated. For example, the vehicle has been automatically braked to a standstill when passing close to an obstacle. The driver now wishes to maneuver the vehicle out of this tight situation without using the braking function. To do this, the driver depresses the brake pedal to or beyond a certain threshold. This is detected, and the automatic braking function of the automatic collision avoidance system is deactivated accordingly. The driver can now maneuver the vehicle without automatic braking intervention.It is then determined that one or more conditions are met indicating that the tight maneuvering situation no longer exists. For example, it may be determined that the vehicle's distance to all obstacles is greater than or equal to a certain minimum distance (e.g., 20 cm). Alternatively, it could be determined that the vehicle's distance to the obstacle that caused the previous braking intervention is greater than a certain minimum distance. Either of these distance criteria indicates that the driver has exited the tight maneuvering situation.

[0024] In response, the automatic braking function is automatically deactivated and thus reactivated. The automatic braking function could therefore remain deactivated, for example, until a minimum distance to all obstacles has been re-established.

[0025] The automatic reactivation of the braking function after deactivation can also be triggered by a location criterion, namely that the vehicle has changed its position by a certain amount (for example, compared to its position when the braking was applied). For automatic reactivation, it could be required, for instance, that the vehicle has moved a certain minimum distance.

[0026] Alternatively, the automatic activation of the braking function can also be triggered by a time criterion, for example, that a certain minimum time period (e.g., since the braking intervention or since starting again) has elapsed.

[0027] It would also be conceivable to reactivate the braking function if the driver no longer presses the brake pedal.

[0028] The deactivation of the braking function need not be global; the braking function could remain partially active after deactivation. A second aspect concerns a method for deactivating an automatic braking function of an automatic collision avoidance system for collision avoidance when parking or maneuvering a motor vehicle according to claim 5, wherein, prior to deactivating the automatic braking function, the automatic collision avoidance system first initiates an automatic braking intervention to avoid a collision with an obstacle located in a first surrounding area. In response to the depressing of the brake pedal up to or beyond the specified brake pedal threshold, the braking function for collision avoidance is then deactivated with respect to the first surrounding area (i.e.,(No further braking intervention occurs due to an obstacle in this first environment area), while the braking function to avoid collisions with an obstacle in another, second environment area remains active (i.e., automatic braking continues as needed to avoid collisions with obstacles in this second environment area).

[0029] For example, the braking function is deactivated for a specific first sector of the vehicle's surroundings around the obstacle that triggered the braking intervention, while remaining active for the other sectors. This partial deactivation of the collision protection can also be visualized, for example, by displaying the first sector differently on a screen in the vehicle's cockpit compared to the other sectors (e.g., the first sector is not color-coded, while the other sectors where collision protection is active are color-coded to indicate that it is active).

[0030] A third aspect concerns an automatic collision avoidance system for avoiding collisions when parking or maneuvering a motor vehicle with a braking function according to claim 6.

[0031] The foregoing descriptions of the inventive method according to the first aspect also apply accordingly to the inventive collision avoidance system according to the third aspect. Advantageous embodiments of the inventive collision avoidance system not explicitly described here correspond to the described advantageous embodiments of the inventive method.

[0032] A fourth aspect concerns an automatic collision avoidance system for avoiding collisions when parking or maneuvering a motor vehicle with a braking function according to claim 7.

[0033] The invention is described below with reference to the accompanying drawings and an exemplary embodiment. These show: Fig. 1 an embodiment of a deactivation of a collision avoidance system according to the invention; and Fig. 2 an embodiment of determining the braking torque M to be set B,FZG depending on the braking torque currently requested manually by the driver via the brake pedal M B,m and the currently requested braking torque M B,auto the automatic braking function.

[0034] Fig. Figure 1 shows an embodiment of a deactivation method according to the invention for a collision avoidance system for avoiding collisions during parking or maneuvering. The method assumes that, first, in step 100, the automatic collision avoidance system, before deactivating the automatic braking function, has triggered an automatic braking intervention to avoid a collision in a tight maneuvering situation with a small obstacle distance, thus braking the vehicle to a standstill. Then, in query 110, it is checked whether the brake pedal signal BP, indicating the current position of the brake pedal, is greater than a threshold value BP. THThe brake pedal signal BP, for example, corresponds to a

[0035] Braking torque. The braking torque signal BP is calculated, for example, from a measured brake pressure. The threshold value BP TH The braking torque, for example, corresponds to the value 3500 Nm.

[0036] If query 110 positively determines that the current value of the brake pedal signal BP is greater than a threshold value BP TH If this is the case, the automatic braking function is deactivated in step 120.

[0037] To implement the automatic braking function of the collision avoidance system, it is intended, for example, that the currently requested braking torque M B,auto the automatic braking function and the braking torque currently requested manually by the driver via the brake pedal M B,m (which can also be zero if the driver is not currently requesting any braking torque) is compared, the maximum of these two signals M B,auto and MB,m is determined and the resulting signal M B,FZG is used as a target value for brake control, as is the case in Fig. 2 is shown.

[0038] To deactivate the automatic braking function, for example, the currently requested braking torque M can be set. B,auto The automatic braking function is disabled depending on the binary signal D via a switchable ramp function RF. Before the braking function is deactivated, the binary signal is 0, and the ramp function RF does not modify the signal (i.e., block RF then acts as a through connection). If query 110 is answered positively, the binary signal D is switched to 1, and the output signal of the ramp function RF is reduced to zero via a ramp and remains at zero as long as the binary signal D = 1. Thus, the collision avoidance system no longer affects signal M. B,FZGof the requested braking torque, and the automatic braking function is deactivated.

[0039] After deactivation, query 130 repeatedly checks whether the respective distance d i of the vehicle to all detected obstacle points i in the vehicle's environment greater than or equal to a certain minimum distance d min (e.g. d min = 20 cm).

[0040] If this is the case, the automatic braking function is automatically reactivated (see step 140). For this purpose, for example, the binary signal D is switched to 0, so that the torque request signal M B,auto the automatic braking function is fed back to the maximum selection (here too, the torque request signal of the automatic braking function fed to the maximum selection can be increased in a ramp-like manner).

Claims

[1] A method for deactivating an automatic braking function of an automatic collision avoidance system for avoiding collisions when parking or maneuvering a motor vehicle, comprising the steps of: - Detecting (110) a depression of the brake pedal up to a certain brake pedal threshold value (BP TH ) a value characteristic of the depression of the brake pedal or above the specific brake pedal threshold value (BP TH ) beyond; - in response thereto, deactivating (120) the automatic braking function of the automatic collision avoidance system; - after deactivating the automatic braking function, determining (130) that one or more conditions for canceling the deactivation of the automatic braking function are met; and - in response thereto, automatically cancelling (140) the deactivation of the automatic braking function. [2] Method according to one of the preceding claims, wherein - the automatic collision avoidance system has first triggered an automatic braking intervention (110) to avoid a collision with a specific obstacle before deactivating the automatic braking function, so that the vehicle is braked to a standstill; - then, when stationary, depress the brake pedal up to the specified brake pedal threshold value (BP TH ) or above the specific brake pedal threshold (BP TH ) is established (110); and - in response to this, the automatic braking function is deactivated (120). [3] Method according to one of the preceding claims, wherein - the automatic collision avoidance system has first triggered an automatic braking intervention to avoid a collision in a tight manoeuvring situation before deactivating the automatic braking function (100); - after deactivation of the automatic braking function, it is determined (130) that one or more conditions are met which indicate that the tight shunting situation no longer exists; and - in response to this, the deactivation of the braking function is automatically cancelled (140). [4] Method according to one of the preceding claims, wherein - after deactivating the automatic braking function, it is determined that the respective distance (d i ) of the vehicle to a specific obstacle or to all obstacles greater than or equal to a specific minimum distance (d min ) is; and - in response to this, the deactivation of the braking function is automatically cancelled (140). [5] A method for deactivating an automatic braking function of an automatic collision avoidance system for avoiding collisions when parking or maneuvering a motor vehicle, comprising the steps of: - Detecting (110) a depression of the brake pedal up to a certain brake pedal threshold value (BP TH ) a value characteristic of the depression of the brake pedal or above the specific brake pedal threshold value (BP TH ) and - in response thereto, deactivating (120) the automatic braking function of the automatic collision avoidance system, wherein - the automatic collision avoidance system has first triggered an automatic braking intervention to avoid a collision with an obstacle located in a first surrounding area before deactivating the automatic braking function (100); and - in response to the depressing of the brake pedal up to the specified brake pedal threshold (BP TH ) or above the specific brake pedal threshold (BP TH) the braking function for collision avoidance is deactivated (120) with respect to the first surrounding area, wherein the braking function for collision avoidance with an obstacle in another, second surrounding area remains active. [6] Automatic collision avoidance system for avoiding collisions when parking or maneuvering a motor vehicle with an automatic braking function, which is designed - pressing the brake pedal down to a certain brake pedal threshold (BP TH ) a quantity characteristic of the depression of the brake pedal (BP TH ) or above the specific brake pedal threshold (BP TH ) to determine - in response to this, to deactivate the automatic braking function of the automatic collision avoidance system, - after deactivating the automatic braking function, determine that one or more conditions for cancelling the deactivation of the automatic braking function are met, and - in response to this, to automatically cancel the deactivation of the automatic braking function. [7] Automatic collision avoidance system for avoiding collisions when parking or maneuvering a motor vehicle with an automatic braking function, which is designed - to trigger an automatic braking intervention to avoid a collision with an obstacle located in a first surrounding area, - pressing the brake pedal down to a certain brake pedal threshold (BP TH ) a quantity characteristic of the depression of the brake pedal (BP TH ) or above the specific brake pedal threshold (BP TH ) and - in response thereto, to deactivate the automatic braking function of the automatic collision avoidance system for avoiding a collision with respect to the first surrounding area, whereby the braking function for avoiding a collision with an obstacle in another, second surrounding area remains active.

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