DE102022111723A1 - METHOD, COMPUTER PROGRAM PRODUCT, DRIVING ASSISTANCE SYSTEM AND VEHICLE - Google Patents

Abstract

A method for operating a driving assistance system (110) for a vehicle (100) is proposed. The vehicle has at least one airbag with an associated impact detection sensor (IDS1, IDS2) and a number of torque sensors (TS1, TS2), which corresponds to a number of drive wheels (101 - 104) of the vehicle (100), the respective torque sensor (TS1, TS2) is assigned to the respective drive wheel (101 - 104). The method comprises:a) receiving (S1) an impact detection sensor signal (IDSS1, IDSS2) from the impact detection sensor (IDS1, IDS2), which is indicative of an impact of the vehicle (100) on an object (210) outside the vehicle (100), b) receiving (S2) a respective torque sensor signal (TSS1, TSS2) from each respective torque sensor (TS1, TS2) which is indicative of a torque acting on the respective wheel (101 - 104), c) determining a respective derived value (ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt) for the received impact detection sensor signal (IDSS1, IDSS2) and for each received torque sensor signal (TSS1, TSS2), where the respective derived value (ΔTSS1/Δt , ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt) is determined based on a respective predetermined function of the respective sensor signal (IDSS1, IDSS2, TSS1, TSS2), d) comparing each respective derived value (ΔTSS1/Δt , ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt) with a respective threshold value (THT1 - THT4, THS), and, e) if the derived value of the impact detection sensor signal (ΔIDSS1/Δt) and at least one of the derived values (ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt) of the torque sensor signals (TSS1, TSS2) is above its respective threshold value (THT1 - THT4, THS), triggering emergency braking of the vehicle (100).

Description

The invention relates to a method for operating a driving assistance system, a computer program product, a driving assistance system and a vehicle.

Well-known vehicles offer autonomous driving functions, which means that the vehicle drives autonomously without the driver controlling the vehicle. Such functions require reliable and robust environmental detection using sensors such as ultrasonic sensors, radar, lidar and/or camera-based systems. Safety is of particular importance in this context, as a vehicle in the event of a collision can cause serious injury to people or animals nearby and/or damage to the vehicle itself or other objects. Regardless of how reliable a sensor system may be, there is always the risk of an undetected malfunction and/or incorrect detection of obstacles in the vicinity of the vehicle, i.e. i.e. an object is not recognized by the sensors. In such a case, the vehicle may collide with the obstacle if the vehicle trajectory crosses the position of the obstacle.

Therefore, it is desirable to have a safety or security system that intervenes even if the collision has already occurred so that the injury or damage caused by the collision is minimized.

The US 2016/0039376 A1 discloses a vehicle bumper structure with a pressure tube-type pedestrian collision detection sensor. The vehicle bumper structure includes a bumper reinforcement, a pressure tube-type pedestrian collision detection sensor and an upper absorber. The upper absorber includes an absorber main body, an absorber upper end portion integrally provided on the vehicle top of the absorber main body, and having a protruding portion which is located on the vehicle top of the bumper reinforcement in relation to the absorber main body at the front and a groove portion formed on a front-rearward vehicle interior side portion of the absorber main body disposed adjacent to the vehicle underside of the upper end portion of the absorber facing the front-rearward direction. Open towards the inside of the vehicle or the underside of the vehicle and which holds a pressure pipe.

It is an object of the present invention to improve the operation of a vehicle with the aid of a driving assistance system.

1. a) Empfangen eines Aufprallerkennungssensorsignals von dem Aufprallerkennungssensor, das indikativ für einen Aufprall des Fahrzeugs auf ein Objekt außerhalb des Fahrzeugs ist,
2. b) Empfangen eines jeweiligen Drehmomentsensorsignals von jedem jeweiligen Drehmomentsensor, das indikativ für ein Drehmoment, das auf das jeweilige Rad wirkt, ist,
3. c) Bestimmen eines jeweiligen abgeleiteten Werts für das empfangene Aufprallerkennungssensorsignal und für jedes empfangene Drehmomentsensorsignal, wobei der jeweilige abgeleitete Wert auf der Basis einer jeweiligen vorbestimmten Funktion des jeweiligen Sensorsignals bestimmt wird,
4. d) Vergleichen jedes jeweiligen abgeleiteten Werts mit einem jeweiligen Schwellenwert, und
5. e) wenn der abgeleitete Wert des Aufprallerkennungssensorsignals und zumindest einer der abgeleiteten Werte der Drehmomentsensorsignale über seinem jeweiligen Schwellenwert liegt, Auslösen einer Notbremsung des Fahrzeugs.

According to a first aspect, a method for operating a driving assistance system for a vehicle is proposed, which has at least one airbag with an associated impact detection sensor and a number of torque sensors that correspond to the number of drive wheels of the vehicle, the respective torque sensor being assigned to the respective drive wheel . The procedure includes:

1. a) receiving an impact detection sensor signal from the impact detection sensor that is indicative of an impact of the vehicle with an object outside the vehicle,
2. b) receiving a respective torque sensor signal from each respective torque sensor that is indicative of a torque acting on the respective wheel,
3. c) determining a respective derived value for the received impact detection sensor signal and for each received torque sensor signal, the respective derived value being determined based on a respective predetermined function of the respective sensor signal,
4. d) comparing each respective derived value with a respective threshold value, and
5. e) if the derived value of the impact detection sensor signal and at least one of the derived values of the torque sensor signals is above its respective threshold value, triggering emergency braking of the vehicle.

This method has the advantage that in the case in which an object in the area surrounding the vehicle was not detected by the vehicle's environment detection system and a collision with the object has occurred, the collision is detected early and with high reliability and the vehicle is stopped by emergency braking so that injury or damage caused by the collision is minimized. The method can be said to mimic the behavior of a human driving the vehicle manually by performing emergency braking even after a collision has occurred as soon as the driver notices that a collision has occurred. Furthermore, by combining information from at least two different sources, i.e. the crash detection sensor signal and the torque sensor signal, to determine whether a collision has occurred, the method is more reliable and robust than systems that rely on only one source of information to determine whether a collision has occurred. The proposed method is particularly suitable for low speeds, such as in automatic parking maneuvers.

The driving assistance system is set up to autonomously control the vehicle during autonomous driving, in particular when parking the vehicle in a parking space. For example, the driving assistance system is designed as a level 3, level 4 or level 5 system or as a level 3, level 4 or level 5 system according to the SAE classification for automated driving systems. The classification system mentioned was published in 2014 by the standards organization SAE International as standard J3016, “Taxonomy and Definitions for Terms Related to On-Road Motor Vehicle Automated Driving Systems”. A Level 3 system is defined as a system in which the driver does not have to monitor the operation of the vehicle but can instead focus his attention on other tasks. The driver must still be able to intervene within a certain period of time if the vehicle requests him to do so. With a Level 4 system, the driver's attention is not required regarding the safety of the operation. With a Level 5 system, human intervention is not required at all.

The airbag and crash detection sensor are standard features that are required by law in most regions. The impact detection sensor is typically used to detect a vehicle impacting an obstacle and to deploy the airbag if the impact is severe enough. In the present method, the impact detection sensor signal is also used to determine whether a collision with an obstacle has occurred, even if the impact is not severe enough to deploy the airbag. That is, the method uses components that are available in the vehicle without the need to add additional components, whereby the system does not increase the complexity and cost of the vehicle. The impact detection sensor signal may preferably be provided as a digital signal, but an analog signal may also be used. The impact detection sensor signal may be provided as a raw sensor signal and/or as a preprocessed signal.

A torque sensor is assigned to each drive wheel of the vehicle. The torque sensor records the torque acting on the respective wheel. The torque can be positive or negative depending on the driving situation (e.g. accelerating, braking, turning, driving uphill or downhill). A two-wheel drive vehicle has at least two torque sensors, and a four-wheel drive vehicle has at least four torque sensors.

In the first step of the method, the driving assistance system receives the impact detection sensor signal from the impact detection sensor and receives the respective torque sensor signal from each respective torque sensor.

It should be noted that the respective sensor signal can be received repeatedly, for example regularly or periodically. The respective sensor signal is preferably received at each time step when the respective sensor provides an updated signal, which can be done, for example, at a rate of at least 10 Hz, preferably at least 50 Hz, more preferably at least 100 Hz and even more preferably above 500 Hz. The frequency at which each sensor provides updated sensor signals may vary between different sensors.

Each sensor signal can be assigned a one-dimensional value at a given time, i.e. H. correspond to a scalar value.

Based on the received sensors, a respective derived value is determined using a respective predetermined function. The predetermined function used may be different for the different sensor signals received. The respective function depends on the respective sensor signal received, i.e. H. the value of the received sensor signal is a variable used to evaluate the function value. The predetermined function can be identity, meaning that the output value is identical to the input value. The predetermined function may depend on the received sensor signal at more than one time, for example, it may depend on the last two received sensor signal values or on more than the last two received sensor signal values. The predetermined function may depend on more than one sensor signal, that is, it may depend on sensor signals received from different sensors of the vehicle.

In one embodiment, the predetermined function is the time difference based on the last two received sensor signal values. The derived value is then the time difference value. The time difference value is indicated, for example, by the difference between the value of the last sensor signal received and the value of the sensor signal received beforehand. You can also say that the respective time difference value of the time corresponds to the derivation of the respective sensor signal. This also means that the at least two sensor signal values are required to determine the time difference value.

In embodiments, the time difference value may be determined based on more than two sensor signal values and/or the time difference value may be determined as an average of two or more specific time difference values for a respective sensor signal.

Each respective particular derived value is then compared to a respective threshold value. The threshold value can be predefined, obtained from a predefined lookup table with a plurality of threshold values and/or determined on the basis of a predetermined function, which is evaluated on the basis of further sensor signals received from further sensors of the vehicle. In preferred embodiments, the threshold is not a fixed value but is dynamic, with its value being determined at a given time depending on driving conditions, environmental conditions, and the like. Further details will be described later.

For example, the threshold value is set individually for each of the sensor signals. For example, the threshold value for the left front wheel torque sensor signal may be a different value than the threshold value for the right front wheel torque sensor signal.

If the result of comparing the respective derived value with the respective threshold shows that the derived value of the impact detection sensor signal and at least one of the derived values of the respective torque signal is above its respective threshold, emergency braking is triggered.

According to one embodiment of the method, the predetermined function is a time derivative of the respective sensor signal, and the derived value is a time difference value.

According to a further embodiment of the method, the respective threshold value is determined on the basis of a number of received sensor signals, the number being at least one acceleration sensor signal, which is received by at least one acceleration sensor of the vehicle, and/or at least one gyrometer sensor signal, which is received by at least one gyrometer of the Vehicle is received includes.

In this embodiment, the threshold value is adaptive based on the additional sensor signals received. The sensor signals in particular indicate a driving state of the vehicle, such as accelerating, braking, driving uphill or downhill and/or turning and/or overcoming a step, such as a curb or the like, of the vehicle. Depending on the driving situation, more or less variations in the torque sensor signals and the impact detection sensor signals are expected, and it is therefore advantageous to adjust the respective threshold value accordingly.

For example, when the vehicle is traveling in a straight line on flat ground and at a constant speed, the torque at the drive wheels is expected to be substantially constant. This means that the time difference is zero. When the vehicle corners, the torque on the inner wheels and the outer wheels changes, so the torque sensor signal will have some fluctuations. Therefore, to avoid false positives, the threshold can be increased in such a situation. Another example is accelerating or braking the vehicle. Depending on the ground surface, different slip occurs on the drive wheels, which causes the torque signal to change over time.

The vehicle may include one or more acceleration sensors and one or more gyrometers, for example, the vehicle includes an acceleration sensor and/or a gyrometer corresponding to each drive wheel of the vehicle. Thus, the threshold value corresponding to the torque sensor signal of each wheel can be determined individually based on the respective additional sensor signals. If the vehicle has only one accelerometer and/or gyrometer, the threshold can be set to an identical value for each wheel.

However, even if the threshold is exceeded by one of the derived values of the torque sensor signals, emergency braking is not triggered unless the derived value of the impact detection sensor signal also exceeds its threshold.

According to a further embodiment of the method, the respective threshold value is determined based on values of the number of received sensor signals using a lookup table in which a plurality of threshold values are stored, each threshold value corresponding to a set of predetermined values of the received sensor signals.

The use of a lookup table has the advantage that the threshold value can be obtained very quickly without requiring the evaluation of a function value or the like, while retaining the advantage of adaptivity.

The majority of the threshold values stored in the lookup table can be determined by testing the vehicle in the actual situations to be detected. This has the advantage that the threshold values stored in the lookup table contain special features of the respective vehicle model and thus take differences in the construction of different vehicle models into account.

• Bestimmen einer Steigung der Fahrbahn, auf der sich das Fahrzeug bewegt, und/oder einer Zeitdifferenz der Steigung auf der Basis des empfangenen Beschleunigungssensorsignals und/oder auf der Basis des empfangenen Gyrometersensorsignals, und
• Bestimmen des Schwellenwerts für jeden abgeleiteten Wert der empfangenen Drehmomentsensorsignale auf der Basis der bestimmten Steigung und/oder der Zeitdifferenz der Steigung.

According to a further embodiment, the method further comprises:

• determining a slope of the road on which the vehicle is moving and/or a time difference of the slope based on the received acceleration sensor signal and/or based on the received gyrometer sensor signal, and
• Determining the threshold for each derived value of the received torque sensor signals based on the determined slope and/or the time difference of the slope.

• Bestimmen einer Gierrate des Fahrzeugs auf der Basis des empfangenen Beschleunigungssensorsignals und/oder auf der Basis des empfangenen Gyrometersensorsignals, und
• Bestimmen des Schwellenwerts für jeden abgeleiteten Wert der empfangenen Drehmomentsensorsignale auf der Basis der bestimmten Gierrate.

According to a further embodiment, the method further comprises:

• determining a yaw rate of the vehicle based on the received acceleration sensor signal and/or based on the received gyrometer sensor signal, and
• Determining the threshold for each derived value of the received torque sensor signals based on the determined yaw rate.

According to a further embodiment of the method, the impact detection sensor comprises a pressure sensor.

The pressure sensor may be implemented to detect air pressure in a closed volume, such as a pipe or a hollow part of the vehicle body. The pressure sensor may also be implemented to detect shock waves resulting from the sudden deformation of a body part of the vehicle when the vehicle impacts an obstacle.

According to a further embodiment of the method, the vehicle comprises a plurality of impact detection sensors that are assigned to different sections of the vehicle, the respective impact detection sensor being set up to detect an impact of an object on the assigned section of the vehicle, wherein step a) includes receiving a respective impact detection sensor signal from each respective impact detection sensor and wherein steps c) to e) are carried out for all received impact detection sensor signals.

For example, a first impact detection sensor is disposed at the front left corner of the vehicle body to detect an impact in a region of the vehicle around the front left corner, and a second impact detection sensor is disposed at the front left right corner of the vehicle body to detect an impact in an area of the vehicle around the front right corner. This allows an impact to be detected with spatial resolution.

Since the torque sensor, which is assigned to the drive wheels, also provides a spatial resolution with regard to the torque, spatial correlations between the torque sensor signals and the impact detection sensor signals can also be taken into account in step e). If the derived value of the torque sensor signal associated with the right front wheel is above its threshold and the derived value of the impact detection sensor signal associated with the front left corner is above its threshold, it can be determined that this is not an impact of an object on the vehicle displays and the emergency braking is not triggered.

In the present embodiment, it may be sufficient if one of the impact detection sensor signals and one of the torque sensor signals are above their respective threshold values to trigger emergency braking.

According to a further embodiment, method step e) further comprises activating the vehicle's hazard warning lights and/or sending an emergency call.

The emergency call can be sent via a wireless communication network, such as a cellular network, in particular a 3G, 4G or 5G cellular network.

According to a further embodiment, method steps a) - e) are carried out during an autonomous driving operation in which the vehicle is autonomously controlled by the driving assistance system.

According to a second aspect, a computer program product is proposed that includes instructions that, when the program is executed by a computer, cause the computer to carry out the method according to the first aspect.

A computer program product, such as a computer program medium, may be in the form of a storage device, such as a memory card, a USB flash drive, a CD-ROM, a DVD, and so on, and/or in the form of a digital data file stored by a server in a Computer network or the like can be downloaded. This can be done, for example, by transferring the corresponding file over a wireless network.

For example, the computer is set up to receive sensor signals and can be integrated into a vehicle to function as a driving assistance system.

• eine Empfangseinheit zum Empfangen eines Aufprallerkennungssensorsignals von dem Aufprallerkennungssensor, das einen Aufprall des Fahrzeugs auf ein Objekt außerhalb des Fahrzeugs anzeigt, und zum Empfangen eines jeweiligen Drehmomentsensorsignals von jedem jeweiligen Drehmomentsensor, das ein Drehmoment anzeigt, das auf das jeweilige Rad wirkt,
• eine Bestimmungseinheit zum Bestimmen eines jeweiligen abgeleiteten Werts für das empfangene Aufprallerkennungssensorsignal und für jedes empfangene Drehmomentsensorsignal, wobei der jeweilige abgeleitete Wert auf der Basis einer jeweiligen vorbestimmten Funktion des jeweiligen Sensorsignals bestimmt wird, eine Vergleichseinheit zum Vergleichen jedes jeweiligen abgeleiteten Werts mit einem jeweiligen Schwellenwert, und
• eine Steuereinheit, die dazu eingerichtet ist, um eine Notbremsung des Fahrzeugs auszulösen, wenn der abgeleitete Wert des Aufprallerkennungssensorsignals und zumindest einer der abgeleiteten Werte der Drehmomentsensorsignale über seinem jeweiligen Schwellenwert liegt.

According to a third aspect, a driving assistance system for a vehicle is proposed which has at least one airbag with an associated impact detection sensor and a number of torque sensors that correspond to a number of drive wheels of the vehicle, the respective torque sensor being assigned to the respective drive wheel of the vehicle. The driving assistance system includes:

• a receiving unit for receiving an impact detection sensor signal from the impact detection sensor indicative of an impact of the vehicle with an object outside the vehicle, and for receiving a respective torque sensor signal from each respective torque sensor indicative of a torque acting on the respective wheel,
• a determination unit for determining a respective derived value for the received impact detection sensor signal and for each received torque sensor signal, the respective derived value being determined based on a respective predetermined function of the respective sensor signal, a comparison unit for comparing each respective derived value with a respective threshold value, and
• a control unit configured to trigger emergency braking of the vehicle when the derived value of the impact detection sensor signal and at least one of the derived values of the torque sensor signals is above its respective threshold value.

The present driving assistance system has the same advantages as those described for the method according to the first aspect. The embodiments and features proposed for the method according to the first aspect can also form features and embodiments of the system in a corresponding manner.

The respective unit of the system, for example the receiving unit, the recognition unit, the determination unit, the comparison unit and the control unit, can be implemented in hardware and/or in software. If the respective unit is implemented in hardware, it can be used as a computer, CPU (central processing unit), ASIC (application specific integrated circuit) or PLC (programmable logic controller). ) must be implemented. When implemented in software, the respective unit can be set up as a computer program product, function, algorithm, routine, as part of a programming code or as an executable object. The software may include a trained machine learning algorithm, such as a neural network or deep learning algorithm. Furthermore, each unit may be implemented as part of a control unit of the vehicle, such as an ECU (engine control unit) or the like.

According to a fourth aspect, a vehicle that includes at least one airbag with an associated impact detection sensor and a number of torque sensors corresponding to a number of drive wheels of the vehicle, the respective torque sensor being assigned to the respective drive wheel, and with a driving assistance system according to the third aspect is proposed.

The invention has been described using various embodiments. It is understood that one or more features of any embodiment may be combined with one or more features of the other embodiments. Additionally, any individual feature or combination of features in each of the embodiments may constitute additional embodiments.

• 1 zeigt eine schematische Ansicht eines Fahrzeugs;
• 2 zeigt beispielhafte graphische Darstellungen, die Drehmomentsensorsignalen und einem Aufprallerkennungssensorsignal entsprechen;
• 3A-D zeigen schematisch ein Fahrzeug in unterschiedlichen Fahrsituationen;
• 4 zeigt ein schematisches Blockdiagramm eines Ausführungsbeispiels eines Fahrassistenzsystems;
• 5 zeigt ein schematisches Blockdiagramm eines Ausführungsbeispiels eines Verfahrens zum Betreiben eines Fahrassistenzsystems.

Further embodiments or aspects of the invention are the subject of the dependent claims and the exemplary embodiments, which are described below with reference to the figures.

• 1 shows a schematic view of a vehicle;
• 2 shows exemplary graphs corresponding to torque sensor signals and an impact detection sensor signal;
• 3A-D show schematically a vehicle in different driving situations;
• 4 shows a schematic block diagram of an exemplary embodiment of a driving assistance system;
• 5 shows a schematic block diagram of an exemplary embodiment of a method for operating a driving assistance system.

In the figures, the same elements are given the same reference numbers unless otherwise stated.

1 shows a schematic view of a vehicle 100, for example a car, that is in an environment 200. The car 100 includes a driving assistance system 110. The driving assistance system 110 can be implemented as an electronic control unit (ECU). The driving assistance system 110 may be implemented along with other controls in a single integrated circuit and/or may share resources such as a CPU, RAM, and so on. The car 100 further includes a plurality of sensors 120, 130. The sensors 120 are implemented, for example, as optical sensors and may include a camera, radar and/or lidar or the like. The optical sensors 120 are set up to capture an image, preferably including depth data, of the surroundings 200 of the vehicle 100 and to output the captured image as an optical sensor signal. The sensors 130 can be designed, for example, as ultrasonic sensors and are set up to detect a distance to objects in the vicinity of the vehicle 100.

In the present embodiment, the car 100 has four wheels 101 - 104, of which the two front wheels 101, 102 are driven by a motor (not shown) to drive the car 100. A respective torque sensor TS1, TS2 is assigned to each front wheel. Each torque sensor TS1, TS2 is set up to detect a torque acting on the respective wheel 101, 102 and to output a respective torque sensor signal TSS1, TSS2 to the driving assistance system 110. In addition, the car 100 has two impact detection sensors IDS1, IDS2 arranged on or near a front bumper of the car. The impact detection sensors IDS1, IDS2 are set up to detect an impact of the vehicle 100 on an object outside the vehicle 100 and to output a respective impact detection sensor signal IDSS1, IDSS2, which indicates the detected impact. The impact detection sensor signal IDSS1, IDSS2 is used, for example, to deploy an airbag (not shown) in the event of a strong impact to protect the occupants of the car 100. In the present exemplary embodiment, the impact detection sensor signals IDSS1, IDSS2 are additionally output to the driving assistance system 110.

The impact detection sensors IDS1, IDS2 are implemented as pressure sensors, for example. That is, its output sensor signal corresponds to a pressure that acts on an area of the vehicle 100, such as the front bumper of the vehicle 100. Since the car 100 has two pressure sensors IDS1, IDS2, in the present exemplary embodiment the first pressure sensor IDS1 can be set up to do so be to detect a pressure that acts on the front left portion of the bumper, and the second pressure sensor IDS2 can be configured to detect a pressure that acts on the front right portion of the bumper. When the car 100 collides with an object on the front left bumper, the sensor signal value IDSS1 of the first pressure sensor IDS1 may be higher than that of the second pressure sensor, indicating that the collision occurs in the front left area of the vehicle. Similarly, when the car 100 collides with the object on the front left bumper, the torque acting on the left front wheel 101 is increased compared to the torque acting on the right front wheel 102.

It is noted that it is not strictly necessary to provide two impact detection sensors IDS1, IDS2, instead, one impact detection sensor may be provided for the processing described below with reference to 2 be enough.

In addition to the in 1 120, 130, IDS1, IDS2, TS1, TS2 shown, the car 100 may have more and/or other sensors, such as wheel speed sensors, steering angle sensors, one or more accelerometers, one or more gyrometers, an antenna for receiving electromagnetic data signals, and the like .

The driving assistance system 110 can be as in 4 shown to be implemented and adapted to perform processing as hereinafter referred to 2 and/or in relation to 4 described.

For example, the driving assistance system 110 receives the torque sensor signals TSS1, TSS2 and the impact detection sensor signals IDSS1, IDSS2 and is set up to generate a respective derived value (see 2 ) for each to determine the received sensor signal based on a respective predetermined function. The predetermined function depends on the value of the respective sensor signal, and the derived value is obtained by evaluating the predetermined function for a specific sensor signal value. In one embodiment, the predetermined function for determining the derived value of the respective received sensor signal is used to normalize the value of the respective received sensor signal based on a predetermined maximum value for the respective sensor. In another example, the predetermined function is the gradient of the received sensor signal with respect to time. In another example, the predetermined function depends on more than one received sensor signal. It should be noted that the predetermined function may be different for different sensor signals, in particular for sensor signals from sensors that detect different physical values.

After determining the derived value for each sensor signal, the respective derived value is compared with a respective threshold value. The respective threshold value may be a predetermined fixed value, may be determined from a lookup table comprising a plurality of predetermined fixed values, and/or may be determined dynamically as a function based on further received sensor signals.

Using a lookup table has the advantage that the threshold can depend on other sensor signals, such as accelerometer and/or gyrometer sensor signals, while at the same time obtaining the threshold at a given time is fast and reliable. For example, the plurality of threshold values stored in the lookup table are determined based on a function that has sensor signals other than input values and/or based on experimental tests in which the car 100 is caused to collide with objects in different driving scenarios. The different driving scenarios may include uphill driving, downhill driving, turning, accelerating, braking, driving on different types of surfaces and/or in different weather conditions, and the like. For example, from the plurality of threshold values stored in the lookup table, a specific threshold value is determined at each specific time based on the driving situation. The driving situation can be determined on the basis of sensor signals, such as acceleration sensors and/or gyrometers and/or rotation angle sensors and the like. Note that it is not necessary to evaluate the specific driving situation, but the sensor signal values can be used directly as input to select or determine an appropriate threshold from the lookup table applicable at a particular time.

If the derived value of the impact detection sensor signal IDS1, IDS2 and at least one of the derived values of the torque sensor signals is above its respective threshold value, emergency braking of the car 100 is triggered. This means that the car 100 is stopped as quickly as possible, which can help prevent injuries and/or damage.

2 shows four exemplary graphs corresponding to torque sensor signals and one graph corresponding to an impact detection sensor signal. In the present exemplary embodiment, the respective graphic representation shows the derived value of the respective sensor signal, the derived value being a time difference of the respective sensor signal. This means that the predetermined function for determining the derived value is the time gradient of the respective sensor signal.

For example, the graphical representations correspond to a vehicle 100 (see 1 ) with four-wheel drive, and each drive wheel has a torque sensor assigned to it. Thus, the top four graphs correspond to the torque sensor signals received from the various torque sensors. In the present embodiment, the vehicle 100 has only one crash detection sensor, so that only the single bottom graph corresponds to the crash detection sensor signal.

The time difference value for each sensor signal is obtained, for example, by the following equation (1). $$\Delta \text{Sig/}\Delta \text{t}=(\text{Sig}\left(\text{tn}\right)-\text{Sig}\left(\text{tn}-1\right))\text{/}\left(\text{tn}-\text{tn}-1\right)$$

"ΔSig/Δt" is the time difference value, "Sig(tn)" is the respective sensor signal value at time "tn", and "Sig(tn-1)" is the respective sensor signal value at time "tn-1", that is, one time step before tn. “tn” is the time at time step n, and “tn-1” is the time at time step n-1 (one time step before n).

The graphic representations show the respective time difference values ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt and ΔIDS1/Δt. All graphs show time t on the horizontal axis. The graphic representations of the Torque sensor signal shows the amplitude of the differential torque ΔTt on the vertical axis, and the graphs of the impact detection sensor signal show the amplitude of the differential sensor signal value ΔS on the vertical axis. In the case of a pressure sensor as an impact detection sensor, this corresponds to the differential pressure.

The graphical representations show the derived values over a period of time when the vehicle 100 is driving in different driving situations, which are shown in 3A - D are shown schematically. The times t1, t2, t3 indicated on the time axis t of each graphical representation correspond to each other. For example, the vehicle 100 is autonomously controlled by the driving assistance system 110 (see FIGS. 1 or 3) in order to park the vehicle in a parking space.

In a first period up to time t1, the vehicle 100 drives straight ahead on a flat surface at a constant speed (see 3A) . Thus, the torque acting on the wheels is essentially constant, so that the respective time difference value ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt is essentially zero in this interval. A respective threshold value THT1, THT2, THT3, THT4 is defined for each time difference value ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt. In this first period, the time difference value ΔIDSS1/Δt of the impact detection sensor signal is also constant. THS indicates the threshold for the time difference value ΔIDSS1/Δt.

In a second period between t1 and t2, the vehicle 100 drives on unsteady ground, such as over a curb and/or through potholes, and/or turns, which is why the torque acting on the various wheels 101 - 104 shows fluctuations and thus also the time difference values ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt show corresponding fluctuations. This is in 3B shown schematically. In the present embodiment, the vehicle 100 includes acceleration sensors and/or gyrometers, and the driving assistance system 110 may detect that the driving state of the vehicle has changed based on sensor signals received from the acceleration sensors and/or gyrometers, resulting in fluctuations in the vehicle Torque caused. Therefore, the threshold value THT1, THT2, THT3, THT4 is adjusted for the respective torque sensor signal TSS1, TSS2 so that the number of false positive values is reduced. In particular, the respective threshold value THT1, THT2, THT3, THT4 is obtained from a lookup table based on the received acceleration sensor signals and/or gyrometer signals. During this time, the time difference value ΔIDSS1/Δt of the impact detection sensor signal is substantially constant and is below the threshold THS, which is also kept constant.

For example, the time difference value ΔTSS4/Δt exceeds its threshold value THT4 during this period. However, since the time difference value ΔIDSS1/Δt of the impact detection sensor signal does not exceed its threshold value THS, no emergency braking is triggered in this case.

In a third period between t2 and t3, the vehicle 100 drives straight ahead again at a constant speed and on a flat surface (see 3C ), so that the torque acting on the wheels 101 - 104 is essentially constant. The threshold values THT1, THT2, THT3, THT4 are therefore reset to the lower value. During this time, the time difference value ΔIDSS1/Δt of the impact detection sensor signal is constant.

At approximately time t3, the time difference value ΔTSS1/Δt of the torque sensor TS1, which is assigned to the left front wheel 101, for example, shows a sharp increase that exceeds the specified threshold THT1. At a similar time, the time difference value ΔIDSS1/Δt of the impact detection sensor signal exceeds its threshold THS. The driving assistance system 110 thus concludes that the vehicle 100 has collided with an obstacle 210, as shown schematically in 3D is shown. Therefore, emergency braking is triggered to stop the vehicle as quickly as possible. In the 3D The situation shown can occur, for example, if a vehicle 100 under autonomous control does not recognize the obstacle 210 in the vicinity of the vehicle 100, which can also be referred to as a “false negative”. In such a situation, the procedure described leads to increased security.

4 shows a schematic block diagram of an embodiment of a driving assistance system 110 for a vehicle 100 (see 1 ), which has at least one airbag with an associated impact detection sensor IDS1, IDS2 (see 1 ) and a number of torque sensors TS1, TS2 (see 1 ), which has a number of drive wheels 101 - 104 (see 1 ) of the vehicle 100, the respective torque sensor TS1, TS2 being assigned to the respective drive wheel 101 - 104. The driving assistance system 110 includes a receiving unit 112 for receiving an impact detection sensor signal IDSS1, IDSS2 (see 1 ) from the impact detection sensor IDS1, IDS2, which indicates an impact of the vehicle 100 on an object 210 outside the vehicle 100, and to Receiving a respective torque sensor signal TSS1, TSS2 from each respective torque sensor TS1, TS2 indicating a torque acting on the respective wheel 101 - 104, and comprising a determination unit 114 for determining a respective derived value ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3 /Δt, ΔTSS4/Δt, ΔIDSS1/Δt (see 2 ) for the received impact detection sensor signal IDSS1, IDSS2 and for each received torque sensor signal TSS1, TSS2, the respective derived value ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt based on a respective predetermined function (see e.g. equation (1) above) of the respective sensor signal IDSS1, IDSS2, TSS1, TSS2 is determined, and comprises a comparison unit 116 for comparing each respective derived value ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt with a respective threshold value THT1 - THT4, THS. In addition, the driving assistance system 110 includes a control unit 118, which is set up to trigger emergency braking of the vehicle 100 when the derived value ΔIDSS1/Δt of the impact detection sensor signal IDSS1, IDSS2 and at least one of the derived values ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/ Δt, ΔTSS4/Δt of the torque sensor signals TSS1, TSS2 exceeds its respective threshold value THT1 - THT4, THS.

5 shows a schematic block diagram of an exemplary embodiment of a method for operating a driving assistance system 110 (see 1 or 4 ) for a vehicle 100 (see 1 ), which has at least one airbag with an associated impact detection sensor IDS1, IDS2 (see 1 ) and a number of torque sensors TS1, TS2 (see 1 ), which has a number of drive wheels 101 - 104 (see 1 ) of the vehicle 100, the respective torque sensor TS1, TS2 being assigned to the respective drive wheel 101 - 104. In a first step S1, an impact detection sensor signal IDSS1, IDSS2, which indicates an impact of the vehicle 100 on an object 210 (see 3D ) outside the vehicle 100, received from the impact detection sensor IDS1, IDS2. In a second step S2, a corresponding torque sensor signal TSS1, TSS2 (see 1 ) from each respective torque sensor TS1, TS2 (see 1 ), which indicates a torque acting on the respective wheel 101 - 104. In a third step S3, a respective derived value ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt (see 2 ) for the received impact detection sensor signal IDSS1, IDSS2 and for each received torque sensor signal TSS1, TSS2, the respective derived value ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt based on a respective predetermined function ( see, for example, equation (1) above) of the respective sensor signal IDSS1, IDSS2, TSS1, TSS2 is determined. In a fourth step S4, each respective derived value ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt is compared with a respective threshold value THT1 - THT4, THS (see 2 ). In a fifth step S5, if the derived value ΔIDSS1/Δt of the impact detection sensor signal DSS1, IDSS2 and at least one of the derived values ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt of the torque sensor signals TSS1, TSS2 are above its respective threshold value THT1 - THT4, THS is present, emergency braking of the vehicle is triggered.

While the present technology has been described in connection with several practical embodiments, it is to be understood that the technology is not intended to be limited to the examples disclosed, but rather is intended to cover various modifications and equivalent arrangements that are within the spirit and scope of the technology are included.

REFERENCE MARKS

100

vehicle

101

wheel

102

wheel

103

wheel

104

wheel

110

Driving assistance system

112

Recording unit

114

Determination unit

116

Comparison unit

118

Control unit

120

sensor

130

sensor

200

Vicinity

210

obstacle

300

underground

310

uneven ground

ΔT

Differential torque

ΔTSS1/Δt

Time difference value

ΔTSS2/Δt

Time difference value

ΔTSS3/Δt

Time difference value

ΔTSS4/Δt

Time difference value

ΔIDSS1/Δt

Time difference value

ΔS

Differential signal

IDS1

Impact detection sensor

IDS2

Impact detection sensor

IDSS1

Impact detection sensor signal

IDSS2

Impact detection sensor signal

S1

Procedural step

S2

Procedural step

S3

Procedural step

S4

Procedural step

S5

Procedural step

Z

Time

t1

time

t2

time

t3

time

THT1

threshold

THT2

threshold

THT3

threshold

ThT4

threshold

THS

threshold

TS1

Torque sensor

TS2

Torque sensor

TSS1

Torque sensor signal

TSS2

Torque sensor signal

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 2016/0039376 A1 [0004]

Claims (13)

Method for operating a driving assistance system (110) for a vehicle (100), which has at least one airbag with an associated impact detection sensor (IDS1, IDS2) and a number of torque sensors (TS1, TS2), which correspond to a number of drive wheels (101 - 104) of the Electric vehicle (100), wherein the respective torque sensor (TS1, TS2) is assigned to the respective drive wheel (101 - 104), the method comprising: a) receiving (S1) an impact detection sensor signal (IDSS1, IDSS2) from the impact detection sensor (IDS1, IDS2), which is indicative of an impact of the vehicle (100) on an object (210) outside the vehicle (100), b) receiving (S2) a respective torque sensor signal (TSS1, TSS2) from each respective torque sensor (TS1, TS2), which is indicative of a torque acting on the respective wheel (101 - 104), c) determining a respective derived value (ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt) for the received impact detection sensor signal (IDSS1, IDSS2) and for each received torque sensor signal (TSS1, TSS2), wherein the respective derived value (ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt) is determined on the basis of a respective predetermined function of the respective sensor signal (IDSS1, IDSS2, TSS1, TSS2), d) comparing each respective derived value (ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt) with a respective threshold value (THT1 - THT4, THS), and e) if the derived value of the impact detection sensor signal (ΔIDSS1/Δt) and at least one of the derived values (ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt) of the torque sensor signals (TSS1, TSS2) are above its respective threshold value (THT1 - THT4, THS), triggering emergency braking of the vehicle (100). Procedure according to Claim 1 , characterized in that the predetermined function is a time derivative of the respective sensor signal (IDSS1, IDSS2, TSS1, TSS2) and the derived value (ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt). Time difference value is. Procedure according to Claim 1 or 2 , characterized in that the respective threshold value (THT1 - THT4, THS) is determined based on a number of received sensor signals, the number being at least one acceleration sensor signal that is received by at least one acceleration sensor of the vehicle (100), and / or at least a gyrometer sensor signal received by at least one gyrometer of the vehicle (100). Procedure according to Claim 3 , characterized in that the respective threshold value (THT1 - THT4, THS) is determined based on values of the number of received sensor signals using a lookup table that stores a plurality of threshold values, each threshold value corresponding to a set of predetermined values of the received sensor signals . Procedure according to Claim 3 or 4 , characterized by : determining an incline of the route on which the vehicle (100) is moving and/or a time difference of the incline based on the received acceleration sensor signal and/or based on the received gyrometer sensor signal, and determining the threshold value (THT1 - THT4) for each derived value (ΔTSS1 /Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt) of the received torque sensor signals (TSS1, TSS2) based on the determined slope and / or the time difference of the slope. Procedure according to one of the Claims 3 until 5 , characterized by : determining a yaw rate of the vehicle based on the received acceleration sensor signal and / or based on the received gyrometer sensor signal, and determining the threshold value (THT1 - THT4) for each derived value ΔTSS1 / Δt, ΔTSS2 / Δt, ΔTSS3 / Δt, ΔTSS4/Δt) of the received torque sensor signals (TSS1, TSS2) based on the determined yaw rate. Method according to one of the preceding claims, characterized in that the impact detection sensor (IDS1, IDS2) comprises a pressure sensor. Method according to one of the preceding claims, characterized in that the vehicle (100) comprises a plurality of impact detection sensors (IDS1, IDS2) which are assigned to different sections of the vehicle (100), the respective impact detection sensor (IDS1, IDS2) being set up for this purpose to detect an impact of the object (210) on the associated section of the vehicle (100), wherein step a) comprises receiving the respective impact detection sensor signal (IDSS1, IDSS2) from the respective impact detection sensor (IDS1, IDS2), and wherein steps c ) to e) are carried out for all received impact detection sensor signals (IDSS1, IDSS2). Method according to one of the preceding claims, characterized in that step e) further comprises activating the hazard warning lights of the vehicle and/or sending an emergency call. Method according to one of the preceding claims, characterized in that the method is carried out during an autonomous driving operation in which the vehicle (100) is autonomously controlled by the driving assistance system (110). Computer program product that includes instructions that, when the program is executed by a computer, cause the computer to carry out the method according to one of the Claims 1 until 10 to carry out. Driving assistance system (110) for a vehicle (100), which has at least one airbag with an associated impact detection sensor (IDS1, IDS2) and a number of torque sensors (TS1, TS2), which correspond to a number of drive wheels (101 -104) of the vehicle (100) corresponds, wherein the respective torque sensor (TS1, TS2) is assigned to the respective drive wheel (101 - 104), wherein the driving assistance system (110) comprises: a receiving unit (1102) for receiving an impact detection sensor signal (IDSS1, IDSS2) from the impact detection sensor (IDS1, IDS2), which is indicative of an impact of the vehicle (100) on an object (210) outside the vehicle (100), and for receiving a respective torque sensor signal (TSS1, TSS2) from each respective torque sensor (TS1, TS2), which is indicative of a torque acting on the respective wheel (101 -104), a determination unit (114) for determining a respective derived value (ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt) for the received impact detection sensor signal (IDSS1, IDSS2) and for each received torque sensor signal (TSS1, TSS2 ), whereby the respective derived value (ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt) is determined based on a respective predetermined function of the respective sensor signal (IDSS1, IDSS2, TSS1, TSS2), a comparison unit (116) for comparing each respective derived value (ΔTSS1/Δt, ΔTSS2/Δt, ΔTSS3/Δt, ΔTSS4/Δt, ΔIDSS1/Δt) with a respective threshold value (THT1 - THT4, THS), and a control unit (118) which is set up to trigger emergency braking of the vehicle (100) when the derived value (ΔIDSS1/Δt) of the impact detection sensor signal (IDSS1, IDSS2) and at least one of the derived values (ΔTSS1/Δt, ΔTSS2/Δt , ΔTSS3/Δt, ΔTSS4/Δt) of the torque sensor signals (TSS1, TSS2) is above its respective threshold value (THT1 - THT4, THS). Vehicle (100), comprising at least one airbag with an associated impact detection sensor (IDS1, IDS2) and a number of torque sensors (TS1, TS2) corresponding to a number of driven wheels (101 - 104) of the vehicle (100), the respective torque sensor ( TS1, TS2) is assigned to the respective drive wheel (101 - 104), and with a driving assistance system (110). Claim 12 .

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