DE102012222490A1 - Method for increasing driving stability of vehicle i.e. motor car, involves detecting sudden tire pressure drop where yaw moment attenuation takes place during braking by driver and/or moment compensation by driver-independent structure - Google Patents

Abstract

The method involves detecting a sudden tire pressure drop i.e. burst of tire, where yaw moment attenuation takes place during braking by a driver and/or yaw moment compensation by a driver-independent structure. A rule portion with developed braking force is determined according to condition of a deviation between a reference greed rate and a measured greed rate. The rule portion with the braking force is constructed according to an outlet of predetermined time. Tire pressure loss recognition is activated if the vehicle drives quicker than minimum speed and/or steering wheel velocity. An independent claim is also included for an electronic control device.

Description

The invention relates to a method according to the preamble of claim 1, its use in a motor vehicle and an electronic control unit according to claim 11.

If, during travel with a vehicle, a sudden pressure loss occurs on a tire, in particular the front axle, the rolling resistance of the wheel in question is suddenly increased, whereby an undesirable and unexpected torque arises about the vertical axis of the vehicle, which leads to a Schiefziehen or in the worst case to a can lead to complete uncontrollability of the vehicle.

From the US 5,934,768 a brake control device is known, with a control device for controlling brake actuators on each wheel of the vehicle, and a device for detecting a pressure loss in any tire of the vehicle. When the air pressure in a tire falls below a predetermined level, the brake actuator is actuated on the wheel laterally opposite to the pressure loss tire. Too low an air pressure is determined by comparing a measured transverse dynamics quantity with a calculated one. For example, a target wheel speed difference between right and left front wheels is calculated based on the steering wheel angle and compared with the measured actual wheel speed difference. If the deviation is outside of a tolerance band, a tire pressure loss is detected.

The US 5,696,681 discloses a method for controlling the driving dynamics of a motor vehicle, in which a control device triggers braking interventions on selected wheels when a sudden tire burst is detected. The detection of a burst tire, for example, based on pressure sensors. Then, a desired trajectory is calculated based on a desired yaw rate and regulated by braking interventions on the front and rear wheels on the left or right side, the difference between actual trajectory and target trajectory.

Furthermore, the term "Electronic Stability Control" (ESC) vehicle dynamics control systems are known in which a desired yaw rate of the vehicle is calculated from a measured steering angle and other vehicle data and compared with an actual yaw rate measured by a sensor. By a driver-independent construction of braking torque on one or more vehicle wheels, in hydraulic braking systems, in particular by activating a hydraulic pump and actuate solenoid valves, a yaw moment is selectively applied, which reduces the difference between the target and actual yaw rate. Such a system for driving stability control is for example from the EP 0 792 229 B1 known.

In order to avoid faulty regulations, it is necessary in the recognition of a tire burst from the vehicle dynamics parameters of the vehicle to trigger a braking intervention only when a clear deviation from the desired behavior has occurred for at least a predetermined period of time. Thus, even if the control is successful, the vehicle may be offset or a potentially dangerous course deviation. In addition, the driver can be frightened and make reflexive violent steering or braking interventions, which further endanger the driving safety.

It is therefore the object of the present invention to avoid destabilization of the affected vehicle caused by sudden pressure loss or tire defect or to correct it as quickly as possible. Further, it is desirable to avoid instabilities caused by a vehement reaction of the driver.

This object is achieved by a method according to claim 1.

Thus, a method for increasing the driving stability of a vehicle is provided, which is equipped with wheel speed sensors on all wheels and a brake system which allows at least one wheel-specific reduction of the braking force. According to the invention, upon detection of a sudden loss of tire pressure, in particular a bursting of a tire, a yawing moment damping takes place during a braking by the driver and / or a yawing moment compensation by a driver-independent build-up of braking force. By immediately correcting brake pressure loss when a tire pressure loss is detected, a yaw moment caused by the ruptured tire is immediately mitigated or actively compensated, thereby largely avoiding significant drift of the vehicle and / or damaging driver irritation which could lead to overreaction in counter steering ,

Preferably, upon detection of a sudden loss of tire pressure during braking by the driver, yaw momentum mitigation is achieved by limiting or reducing the driver requested or applied braking force on the defective wheel. Since the burst tires brake more and thus produce a disturbing yaw moment, the brake pressure applied by the driver is reduced at the wheel at which the burst tire is located; the annoying yaw moment is weakened or limited. Thus, only with an anti-lock braking system equipped vehicles are kept manageable in the event of a tire failure for the driver.

In a vehicle with a braking system, which allows a driver-independent wheel-specific structure of braking force and in particular includes a vehicle dynamics control, preferably occurs upon detection of a sudden loss of tire pressure for yaw moment compensation, a driver-independent structure of braking force on the wheel, which is opposite to the defective wheel on the same axis. Thus, even if the driver does not brake, a yaw moment caused by the ruptured tire can be compensated and a risk to driving safety can be avoided. In particular, yaw moment compensation may be performed independently of driver braking, i. also in addition to a yaw moment weakening.

Particularly preferably, when the tire pressure loss is detected, a first portion of the braking force is built up as the control component, wherein in particular the amount of the first component depends on the yaw acceleration and / or vehicle speed present and / or on an estimated friction value and / or on a brake actuation when the sudden tire pressure loss is detected the driver is chosen. This precontrol allows immediate compensation of the yawing moment caused by the bursting of the tire, since no previously required exceeding of control thresholds and thus a delayed reaction due to the vehicle inertia delays the braking intervention. By taking into account suitable parameters, a suitable dimensioning of the braking intervention can take place.

It is particularly advantageous if at least one further portion of the built-up braking force (or also the entire braking force) is determined as a control component in accordance with a deviation between a reference yaw rate and a measured yaw rate, wherein in particular after the expiry of a predetermined time period only the control portion of the braking force is established , A regulation of the yaw rate difference allows a long-term and comfortable minimization of occurring Störgiermomente. Degrading the input tax also causes the driver to be slow to apply a compensating steering angle in order to stay on the desired course. This has the advantage that the driver gets notified of the problem of vehicle wrenching and is thus made aware of the driving dynamics problem.

Conveniently, upon detection of a sudden loss of tire pressure, a predetermined braking force difference is set between the defective wheel and the opposite wheel on the same axis, which preferably has a predetermined fixed amount. On the basis of determined at the time of sudden tire pressure loss parameters occurring Störgiermoment can also be determined without yaw rate sensor at least approximately and compensated by a suitable braking force difference or at least mitigated.

After detected tire pressure loss, the gradient of a brake actuation by the driver is preferably limited, wherein in particular the pressure build-up in the wheel opposite the defective wheel takes place on the same axis in accordance with a brake slip control of the defective wheel. The burst tire causes a vehicle behavior which resembles braking on a page-wise different coefficient of friction (μ-split situation), i. by different transferable braking forces an increasing yaw moment is caused in the course of braking. This is weakened or delayed built, leaving the driver enough time for a metered counter steering.

It is expedient if, for the at least partial yaw moment compensation, a steering torque is introduced into the steering line, which preferably has a predefined fixed amount, which is selected in particular as a function of the yaw acceleration and / or vehicle speed and / or an estimated coefficient of friction when the tire is detected. Since low-priced vehicles increasingly have an electric power steering system, this can be used to build up a yaw moment, which can indicate to the driver the appropriate counter-steering direction and support him in countersteering.

Preferably, a tire pressure loss detection is activated when the vehicle is running faster than a minimum speed and / or the steering wheel speed falls below a predetermined steering threshold and / or the engine torque is within a predetermined engine tolerance band and / or the wheel speed of all wheels for a second predetermined time period in a predetermined wheel speed tolerance band lies. Especially when driving on a highway, a burst tire can cause serious accidents due to the high vehicle speeds. At the same time, well-defined driving conditions are often present, which enable a reliable detection of a sudden loss of tire pressure or of a tire blow even from wheel speed information.

Particularly preferably, a sudden loss of tire pressure is detected when the wheel speed of a rear wheel drops abruptly or the Wheel speed of a front wheel drops abruptly without the corresponding rear wheel shows a corresponding behavior and / or the sudden tire pressure loss is detected when a wheel associated with the pressure sensor shows a sudden reduced pressure. If there are pressure sensors that allow a sufficient pressure measurement, a sudden jump in the measured pressure or an error message of the pressure sensor can be considered as a sole condition or in addition to the detection of a tire puncture. A sudden drop in the wheel speed here means a decrease in the measured wheel speed between two directly successive measurements exceeding a predetermined threshold step value. In addition, it may be provided as an additional condition to check an approximately constant before the jump wheel speed. Correspondingly, an abruptly reduced pressure can be detected if, after a plurality of almost constant pressure measurement values, a change in the pressure exceeding a predetermined threshold value is detected. In order to avoid misrecognition, with sufficient measuring frequency of the respective sensor, a following pressure or wheel speed measured value can also be taken into account. From wheel speed information, a sudden loss of tire pressure can therefore be detected when a wheel shows a sudden change in the rotational behavior, which was not caused by a changed coefficient of friction (since the corresponding front or rear wheel shows no change in the rotational behavior).

The invention further relates to the use of a method according to the invention in a motor vehicle, which is driven by an internal combustion engine and / or one or more electric motors.

Furthermore, the invention relates to an electronic control unit for a brake system, with an interface for at least two wheel speed sensors, comprising or connected to a hydraulic unit with at least one solenoid valve, which has a computing unit that performs a method according to the invention. For example, it may be a kernredundanten microcontroller.

Further preferred embodiments will become apparent from the subclaims and the following description of an embodiment with reference to figures.

Show it

1a a schematic representation of a motor vehicle,

1b a schematic structure of a hydraulic brake system,

2 an embodiment of the yaw moment attenuation, and

3 an embodiment of the yaw moment compensation.

1a shows a schematic representation of a motor vehicle 1 , which is suitable for carrying out a method according to the invention with both a yaw moment attenuation and a yaw moment compensation. It has a drive motor 2 driving at least a part of the wheels of the vehicle, in particular the front wheels, a steering wheel 3 , a brake pedal 4 , which with a tandem master cylinder (THZ) 13 is connected, and four individually controllable wheel brakes 10a - 10d on. In addition to hydraulic friction brakes electromechanically actuated friction brakes can be used as wheel brakes on one, several or all wheels. The vehicle can also have an electric drive, wherein in particular the braking torque on a wheel can be generated at least partially by an electric machine operated as a generator, which is assigned only to this wheel.

In order to detect driving-dynamic states, in a vehicle equipped with a vehicle dynamics control system, a steering angle sensor is provided 12 , four wheel speed sensors 9a - 9d , a lateral acceleration sensor 5 , a yaw rate sensor 6 and at least one pressure sensor 14 for the brake pressure generated by the brake pedal. In this case, the pressure sensor 14 also be replaced by a Pedalweg- or pedal force sensor, if the auxiliary pressure source is arranged such that a brake pressure built by the driver of the auxiliary pressure source is indistinguishable or an electromechanical brake actuator is used with known relationship between pedal position and braking torque. If vehicle 1 has only an anti-lock or brake slip control can on steering angle sensor 12 , Lateral acceleration sensor 5 , Yaw rate sensor 6 and, if necessary, pressure sensor 14 also be waived, as for a brake slip control only Raddrehzahlsensoren 9a . 9b . 9c . 9d required are.

The electronic control unit (ECU) 7 receives the data from the various sensors and controls the hydraulic unit (HCU) 8th , In addition, the current of drive motor 2 generated driving torque and the torque desired by the driver determined. It may also be indirectly determined variables that are derived for example from a motor map and the electronic control unit 7 via an interface 11 a vehicle data bus such as CAN can be transmitted from the engine control unit, not shown.

The driving behavior of the motor vehicle 1 is significantly influenced by the suspension design, among other things, wheel load distribution, elasticity of the suspension and tire properties determine the self-steering behavior. In certain driving situations, which are characterized by a predetermined, desired radius of curvature and the coefficient of friction between the tire and the road, there may be a loss of driving stability, the driver's desired steering behavior can not be achieved with the given suspension design. With the present in a vehicle dynamics control sensors, the driver's request can be detected and the implementation can be checked by the vehicle.

1b shows a schematic structure of a hydraulic brake system, in which the driver-operated brake pedal 4 with or without auxiliary power on a tandem master cylinder 13 acts, which causes a pressure build-up in a first brake circuit I and a second brake circuit II. Two wheel brakes each 10 are arranged in a brake circuit; in addition to the black and white division shown here, in which the wheel brakes 10a . 10b the front axle the first brake circuit I and the wheel brakes 10c . 10d the rear axle are assigned to the second brake circuit II, a diagonal distribution is also possible, in each case a wheel brake of the front axle and a wheel brake of the rear axle are assigned to a brake circuit. The in the master cylinder 13 built-up pressure is by means of pressure sensor 14 measured.

About solenoid valves by the electronic control unit, not shown 7 can be controlled, the brake pressures in the wheel brakes can be modulated. Every wheel brake 10 Here is a normally open inlet valve 24 and a normally closed exhaust valve 25 assigned. During a brake slip control, for example, the pressure in the wheel brake 10a be reduced by intake valve 24a is closed to prevent further increase of the pressure by a pedal operation of the driver, and exhaust valve 25a is opened to brake fluid in a low-pressure accumulator 22 derive. If the low pressure accumulator 22 is filled by an electric motor 19 driven return pump 20 activated, the suction side with the low-pressure accumulator 22 and the exhaust side thereof with the master cylinder 13 connected is. Corresponding to the procedure described here in brake circuit I, the pressure in one or both wheel brakes can also be used in the basically identical brake circuit II 10c . 10d be reduced if that or the intake valves 24c . 24d closed and over the or the open exhaust valves 25c . 25d Brake fluid in the low-level memory 23 derive. Return pump 21 , which expediently also by electric motor 19 can be activated to low pressure accumulator 23 to empty.

Vehicles that are equipped with a vehicle dynamics control also have in each brake circuit I / II a normally open isolation valve 16 / 18 on, which is arranged between the outlet of the return pump and the master cylinder, and a normally closed changeover valve 15 / 17 , which is arranged between the inlet of the return pump and the master cylinder. This allows a driver-independent pressure build-up in one or both wheel brakes of a brake circuit. For example, in wheel brake 10a a braking force are built up, so will cutoff valve 16 closed, changeover valve 15 opened and return pump 20 activated. To prevent being in wheel brake 10b Also pressure is built up, before activation of the pump inlet valve 25b getting closed.

2 shows an embodiment of the yaw moment attenuation, wherein the timing of the wheel speed v, ie the wheel speeds v _{front, left of} the left front wheel and v _{front, right of} the right front wheel are shown over the time t in the upper diagram. The lower diagram shows the time course of the brake pressure p, in which the pressure p _driver in the master cylinder and the pressures p _{front, left} in the wheel brake of the left front wheel and p _{front, right} in the wheel brake of the right front wheel are shown. At time t ₀ , tire damage occurs at the left front wheel, whereupon the driver brakes at time t ₁ . Subsequently, the following measures are taken:
By means of a pressure sensor or a pressure model, the pressure is determined, which sets the driver in the master cylinder as a form. For example, the pressure according to p _driver = f (vehicle deceleration) are calculated, wherein the vehicle deceleration is advantageously determined based on the wheel speeds of the wheels not affected by the puncture.

As soon as the _driver pre-pressure p _{driver has reached} a first predefined threshold value, that is to say at the time t ₂ , the intake valve becomes 24a closed on the left front wheel (with the puncture). If the driver pre-pressure reaches a second predetermined threshold value, ie at time t ₃ , which is higher by a predetermined pressure difference ΔP than the first threshold value, inlet valve also becomes 24b the right front wheel (with the tire intact) closed. Due to the pressure difference is a disturbing Yaw moment compensated, which arises because the defective wheel generates a stronger braking force due to the increased rolling resistance at the same brake pressure. Another pressure build-up in the wheel brakes of the front axle is only pulsed.

Due to a reduced frictional connection between the defective tire and the road surface, the defective wheel tends to block even after a slight build-up of pressure. It is therefore advantageous to carry out a brake slip control on the affected wheel with a sensitively connected control threshold or a reduced setpoint slip. At time t ₄ , the control threshold is exceeded on the left front wheel and started a known ABS control.

• – Erfolgt ein Druckabbau am defekten Rad, so erfolgt auch ein vorzugsweise um einen vorgegebenen Faktor bzw. eine vorgegebene Differenz verringerter Druckabbau am intakten Rad, wie im Diagramm kurz nach t₄ dargestellt ist.
• – Ein Druckaufbau am intakten Rad wird nur dann vorgenommem, wenn zeitgleich auch am defekten Rad Druck aufgebaut werden kann bzw. eine vorgegebene Wartezeit verstrichen ist.
• – Wenn das defekte Rad gerade instabil ist, sich also in einer Druckabbauphase mit anschließendem Druckhalten befindet, wird ein Druckaufbau am intakten Rad unterlassen.

In principle, the intact right front wheel could brake much more than the defective one if its own blocking pressure were set. However, this would cause strong yawing moments that could cause the vehicle to spin. To minimize yaw moments caused by the asymmetric distribution of braking force between the left and right front wheels, the pressure build-up gradient of the right front wheel is limited. Ie an increase in pressure up to the own blocking pressure level is carried out only moderately on the right front wheel:

• - If a pressure reduction on the defective wheel, it is also a preferably by a predetermined factor or a predetermined difference reduced pressure reduction on the intact wheel, as shown in the diagram shortly after t ₄ .
• - A pressure buildup on the intact wheel is only vorgenommem, if at the same time at the defective wheel pressure can be built or a predetermined waiting time has elapsed.
• - If the defective wheel is just unstable, ie is in a pressure reduction phase with subsequent pressure hold, a pressure build-up on the intact wheel is omitted.

An existing anti-lock control is thus modified as an alternative or in addition to an active pressure build-up, preferably by performing a yaw moment attenuation when the driver operates the brake before, during or after a tire pressure loss. Thus, even vehicles equipped with an anti-lock braking system or a brake slip control system (ABS only) can be optimally conditioned in the event of a tire blow-out and be kept manageable for the driver.

If the brake system of the vehicle permits a driver-independent build-up of braking force, preferably an active yaw moment compensation is also provided. In order to avoid vehicle instability due to a puncture, it is advantageous to perform an active pressure build-up on the other wheel of the same axle immediately after detection of the situation, wherein the applied by the pressure build-up moment about the vehicle vertical axis should compensate for the moment of the burst tire as accurately as possible.

According to a particularly preferred embodiment of the invention, it is proposed here to carry out the height of the pressure build-up as a function of one or more of the following parameters. A first parameter is the vehicle speed, since the brake torque occurring due to the tire pressure loss depends on the vehicle speed. A second parameter is the yaw pressure or the yaw acceleration that occurs immediately after the tire burst. Preferably, an estimated coefficient of adhesion between the roadway and the tire is taken into account as the third parameter.

Since today's ESC systems are activated only at relatively high deviations between the measured yaw rate and the largely based on the steering angle target yaw rate, which occur in particular over a longer time interval, a vehicle according to the prior art would already deviates significantly from the driver specification Show yaw reaction before it comes to a yaw moment control.

Appropriately, the active or driver-independent pressure build-up takes place at least initially in the form of precontrol, ie a constant or adjusted based on the above parameters braking torque is built up in a time interval to which a driving dynamics control according to the prior art would not intervene due to control deviation.

According to a particularly preferred embodiment of the invention, this pilot component is slowly reduced to zero during a defined time of, for example, 2 seconds, so that the further control is taken over by the ESC. Thus, the feedforward control is based on proven sensor technology (yaw rate sensor, steering wheel angle sensor, lateral acceleration sensor, wheel speed sensors) based ESC control. To make this transition as homogeneous as possible, it is most preferred to lower the control thresholds (e.g., for the difference between the target and actual yaw rates) in the ESC when the event of the tire burst has been detected.

The following is a vehicle with a hydraulic braking system as in 1 assumed that a driver-independent Pressure build-up on one or more individual wheels is possible by a hydraulic pump is activated and solenoid valves are controlled properly. In principle, however, the method according to the invention can also be carried out with an electromechanical brake system.

3 shows an embodiment of the yaw moment compensation, wherein the upper diagram temporal courses of the measured yaw rate Ψ. _act , the reference yaw rate in calculated in a vehicle model. _ref and the driver's predetermined steering angle δ _driver shows. In the lower diagram, an amplification factor K and the brake pressure proportional to the braking force P _{front, right} above the time t are set.

At time t ₀ , the left front tire bursts and is reliably detected. The bursting of the tire creates an undesirable vehicle yaw rate Ψ. _act in left direction. A driving dynamics control according to the prior art would only request a compensating yaw moment by the structure of braking torque when the yaw rate deviation exceeds a predetermined activation threshold ΔΨ .thr, ie the behavior of the vehicle differs significantly from the desired. In a method according to the invention, an active pressure build-up in the wheel brake or a build-up of braking force by the respective brake actuator is started by precontrol, whereby the brake linings are applied to the friction surface. This overcoming of the clearance is completed at time t ₁ .

So that a vehicle dynamics control ESC starts as early as possible with a stabilizing wheel-individual pressure build-up, entry-delaying time filters are deactivated when the tire burst is detected and the activation threshold ΔΨ. _{thr of} the ESC is reduced to a very low value, in particular 1 ° / s. In the example shown, the driver reacts to the slight turning away of the vehicle to the left (positive yaw rate) with a steering angle specification δ _driver to the right (negative values), which also results in a negative reference yaw rate Ψ. _ref yields.

Because of the control deviation between the measured actual yaw rate and the calculated reference yaw rate, the ESC controller, for example a pure proportional controller (P controller), determines a brake request or a brake pressure P _{front, right, req to be established} in the wheel brake of the right front wheel. P _{front, right, req} = K · (Ψ. _Act - Ψ _ref )

Conveniently, the gain K is set to a high start value K _max when entering the control. Thus, an early strong braking intervention takes place before the control deviation has led to a significant offset of the vehicle. It is advantageous if the amount of K is _normally reduced from a time t ₂ to a normal value K, which in particular corresponds to the amplification factor of a yaw moment control (or the P-part of the control) according to the prior art.

Preferably, the time t _{2 is selected} such that the amplification factor is reduced when the disturbing yaw rate caused by the tire burst first becomes zero (in the case of the vehicle initially traveling straight ahead, ie at the intersection of Ψ. _Act with the zero line). As a result of the particularly continuous reduction of the amplification factor, the usual value K _normally reappears at time t ₃ . The time interval of t ₃ and t ₂ should be a few seconds, in particular about 2 s, so that the driver can adjust to the situation by a permanently adjusted and only slightly varying steering angle δ _driver .

According to a preferred embodiment of the invention, in addition to the P component, the ESC controller also comprises a D component (differential component), which advantageously advantageously intervenes much earlier than the pure P controller. While the P-controller builds its braking intervention only with increasing control deviation, the D-controller responds already when a control deviation arises when an undesirable gradient of the yaw rate, ie a yaw acceleration builds up. In the example of 3 A D-controller would have reached its maximum manipulated variable almost at time t ₁ . Very particularly preferably, instead of or in addition to the modification of the P regulator, the amplification factor K _D for the D component of the yaw moment control is also dynamically increased. The time course of K _D is preferably selected in accordance with the course of K discussed above, whereby a faster reduction of K _D can also be provided.

While the embodiment shown above shows a straight ahead of the vehicle, the measures described are activated in any curve situations according to the inventive method. The threshold for determining the switching time is then selected based on the yaw rate present at the time the tire is detected. Thus, a zero crossing of the measured yaw rate corrected by the originally present value takes place.

An alternative preferred embodiment provides, in conjunction with the ESC / ABS measures or independently thereof via an applied, limited steering torque (short steering pulse or steering torque that temporally degrades) compensate the steering effect of the burst tire to influence. This is preferably done on the basis of the information of the tire air pressure as the previous measures. The expediently gradual reduction of the compensatory steering torque has the advantage that a driver acquisition / driver information is effected.

A further preferred embodiment provides that the ESC and / or steering measures also take place when the driver is accelerating in this driving situation, in particular for a limited period of time.

By an early and strong engrossing an ESC control and / or occurs in the event of a brake ABS control at a detected tire burst, the vehicle behaves uncritically during the entire control process and remains easily manageable by an unskilled driver, which consequential damage can be avoided.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been 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 5934768 [0003]
• US 5696681 [0004]
• EP 0792229 B1 [0005]

Claims (11)

A method for increasing the driving stability of a vehicle, which is equipped with wheel speed sensors on all wheels and a braking system that allows at least a wheel-individual reduction of braking force, characterized in that upon detection of a sudden loss of tire pressure, in particular a bursting of a tire, a yaw moment during a braking done by the driver and / or a yaw moment compensation by a driver-independent structure of braking force. A method according to claim 1, characterized in that upon detection of a sudden loss of tire pressure during braking by the driver, a yaw moment attenuation takes place by the driver requested or with or without auxiliary force applied braking force on the defective wheel is limited or reduced. A method according to claim 1 or 2, characterized in that in a vehicle with a braking system, which allows a driver-independent wheel-specific structure of braking force and in particular comprises a vehicle dynamics control, upon detection of a sudden loss of tire pressure for yaw moment compensation, a driver-independent construction of braking force takes place on the wheel, which the faulty wheel on the same axis, wherein the yaw moment compensation is made in particular independent of a braking by the driver. A method according to claim 3, characterized in that when detected tire pressure loss, a first portion of the braking force is constructed as a control component, wherein in particular the amount of the first portion depending on the present upon detection of the sudden tire pressure loss yaw acceleration and / or vehicle speed and / or an estimated coefficient of friction and / or is selected by a brake application by the driver. A method according to claim 3 or 4, characterized in that at least a portion of the built-up braking force is determined as a control component in accordance with a deviation between a Referenzgierrate and a measured yaw rate, wherein in particular after the expiry of a predetermined period of time only the rule portion of the braking force is established. Method according to at least one of the preceding claims, characterized in that upon detection of a sudden loss of tire pressure, a predetermined braking force difference between the defective wheel and the opposite wheel on the same axis is set, which preferably has a predetermined fixed amount, in particular depending on the Detecting the sudden tire pressure loss present yaw acceleration and / or vehicle speed and / or an estimated coefficient of friction is selected. Method according to at least one of the preceding claims, characterized in that the gradient of a brake actuation is limited by the driver after detected tire pressure loss, in particular the pressure build-up in the wheel, which is the defective wheel on the same axis, in accordance with a brake slip control of the defective wheel , Method according to at least one of the preceding claims, characterized in that for the at least partial yaw moment compensation a steering torque is introduced into the steering line, which preferably has a predetermined fixed amount, in particular depending on the present when detecting the tire breakage yaw acceleration and / or vehicle speed and / or an estimated coefficient of friction is selected. Method according to at least one of the preceding claims, characterized in that a tire pressure loss detection is activated when the vehicle is running faster than a minimum speed and / or the steering wheel speed falls below a predetermined steering threshold and / or the engine torque is within a predetermined engine tolerance band and / or the wheel speed all wheels for a second predetermined period of time in a given Radgeschwindigkeitstoleranzband and that a sudden loss of tire pressure is detected when the wheel speed of a rear wheel drops abruptly or the wheel speed of a front wheel drops abruptly without the corresponding rear wheel shows a corresponding behavior and / or the Rad associated pressure sensor shows a sudden reduced pressure. Use of a method according to at least one of the preceding claims in a motor vehicle which is driven by an internal combustion engine and / or one or more electric motors. Electronic control unit for a brake system, with an interface for at least two wheel speed sensors, comprising or connected to a hydraulic unit with at least one solenoid valve, characterized by a computing unit, the a method according to any one of claims 1 to 10 executes.

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