DE102008003079A1 - Passenger protection unit i.e. driving dynamics regulation, controlling method for vehicle i.e. motor vehicle, involves controlling passenger protection unit in dependence of yaw that is determined by wheel speed sensor systems - Google Patents

Abstract

The method involves detecting a collision in dependence of a signal of an impact sensor system (AS), and determining a yaw by wheel speed sensor systems (RZ1-RZ4) in dependence of the collision. A passenger protection unit (FR) is controlled in dependence of the yaw. An impact location is determined in dependence of the yaw and the signal, where the passenger protection unit is controlled in dependence of the impact location. The collision is classified in dependence of the signal and the yaw, where the passenger protection unit controlled in dependence of the classification of the collision. An independent claim is also included for a controller for controlling a passenger protection unit of a vehicle.

Description

State of the art

The The invention relates to a method and a control device for Control of personal protective equipment for a vehicle according to the preamble of the independent claims.

Out DE 10 2006 007 987 A1 It is already known to control rollover protection in dependence on the lateral speed and a slip angle. To determine these dynamic driving variables, among other things, the yaw rate and the wheel speeds determined with the aid of a yaw rate sensor can be used.

Disclosure of the invention

The inventive method or the invention Control device for controlling personal protection devices for a vehicle having the features of the independent claims In contrast, have the advantage that the yaw motion in a collision is determined by means of the wheel speed sensor, so that the yaw motion determined robust and reliable becomes. A yaw rate sensor would namely at a strong collision by the collision very strong in its function be impaired, so that such a yaw rate sensor at least temporarily, no longer deliver reliable results would. According to the invention now the yawing reliably determined in a collision case, so that then personal protective equipment such as a vehicle dynamics control as active Personal protective equipment or passive personal protection adapted to the situation can be controlled.

Especially in situations with multiple collisions, the inventive Method or the control device according to the invention to mitigate the consequences of accidents by stabilizing driving interventions to lead. Such interventions can be used, for example Help active steering systems or wheel-specific braking the vehicle movement influence. This leads to a bigger one Safety of the vehicle occupants and reduces the consequences of accidents.

The Driving personal protection means in this case the activation such passenger protection means as a vehicle dynamics control, a Brakes, airbags and belt tensioners, crash-active headrests etc. A vehicle dynamics control such as ESP can by means of various Akturen (steering, brake, active suspension) intervene.

Under a control device is presently an electrical device understood, the sensor signals processed and in dependence thereof generates drive signals.

The Interfaces can be hardware and / or software be educated. In particular, it is possible that the first and second interface form a common interface, for example, as part of a so-called system ASIC, the most diverse Functions for the control unit includes. The Interfaces may be in a software implementation also on a microcontroller, for example as an evaluation circuit to be available.

When first signal of the impact sensor such as an acceleration, a Air pressure and / or a structure-borne sound sensor arrives single signal, for example, an acceleration signal itself or a signal derived therefrom, or else a vector of different ones Single signals in question. The impact sensor can be at appropriate Be distributed throughout the vehicle, d. H. for example, concentrated in a sensor control unit or outsourced to the Vehicle front or on the sides of the vehicle. When using a Structure-borne sound sensors are suitable couplings to the Vehicle chassis necessary to ensure reliable transmission of structure-borne noise signals from the impact site to the structure-borne sound sensor to ensure.

For the second signal is also what the first Signal was said, the wheel speed sensor is a conventional Sensors, such as Hall sensors or other inductive concepts.

The Evaluation circuit can be hardware and / or software be realized, in particular for processor types like microcontrollers, microprocessors also used with more than one computer core can be. As a hardware design For example, a so-called ASIC can be used with a fixed program sequence. The collision detection module, the yaw motion detection module and the others in the dependent ones Claims mentioned modules are parts of the evaluation and may also be hardware and / or software be educated.

The Drive circuit, for example, also like the interface parts be the system ASICs or part of the evaluation circuit and also It can be designed in terms of hardware and / or software become. Usually, the drive circuit provides the Interface from the controller to the outside Personal security equipment located outside the control unit are located.

The yaw movement is understood to mean a rotation about the vertical axis of the vehicle. usual For example, the yaw rate or quantities derived therefrom can be determined, for example, with the aid of micromechanical sensors, as used by the ESP.

Also the switch, which is intended for this, in case of collision on the determination of the yaw motion by means of the wheel speed sensor Switching can be hardware and / or software be educated. In particular, for example, the switch as an if-then condition is formed, i. H. if a collision occurs, then the yaw motion based on the signals of the wheel speed sensor determined.

By those listed in the dependent claims Measures and developments are advantageous improvements of the specified in the independent claims Method or control device for controlling personal protection devices possible for a vehicle.

It is advantageous that a place of impact depending on the yawing motion and the first signal, d. H. the signal of the impact sensor is determined, the personal protection then depending be controlled by this impact location. The first signal, for example the signal of an acceleration sensor indicates on which side the impact, d. H. the collision took place. Based on Yaw movement is detected, in which direction the vehicle turns around the vehicle's vertical axis, ie clockwise or counterclockwise. From this it can be estimated in which area the Collision took place. This determines which and optionally how to control the corresponding personal protective equipment. The Evaluation circuit has for an impact detection module, which are also formed in hardware and / or software can.

It is also advantageous that, depending on the signal the impact sensor and the yaw motion a classification of the Collision occurs, whereby the control in dependence is performed by the classification. For the classification usually three classes are used for example, the classes are classified according to crash types and / or crash severity are divided. The corresponding class then determines whether and which and how strong the personal protective equipment is to be controlled. Therefor In turn, the evaluation circuit has a classification module, be designed in hardware and / or software can.

It is further advantageous that on the basis of the sign of the signal the impact sensor is closed in an impact direction and by comparing the wheel speeds to one direction of rotation. The control then takes place as a function of the direction of impact and the direction of rotation. The direction of rotation can be determined be that the wheels that are turning in the Compared to the center of rotation located further outward, with higher Wheel speed is moving as the wheels get closer located at the center of rotation.

Farther it is advantageous that respective signals of the wheel speed sensor in each case a vehicle side are averaged and the resulting averages then compared with each other to determine the yawing motion. It can also the difference or the individual values to do so used to determine the rotational speed, etc. Essential Here is that the measured wheel speeds are not due to ESP braking interventions or the motor drive torque are corrupted. Ie. one takes preferably the wheels of a non-driven axle or at least in the short term reduces the drive torque and / or suppresses ESP interventions. That is for example possible because in or shortly after the collision only at the front axle ESP interventions are done while still using Help the rear wheels the yaw motion is determined.

It is also advantageous that the personal protection means, in particular a driving dynamics control is controlled to in a collision case, in particular with possible multiple collisions a mitigation of the consequences of an accident to achieve stabilization of the vehicle.

embodiments The invention are illustrated in the drawings and in the explained in more detail below description.

It demonstrate

1 a block diagram of the control device according to the invention with connected components in the motor vehicle,

2 an exemplary collision,

3 a flowchart of the method according to the invention and

4 a temporal evolution of the wheel speed in a collision.

1 shows a block diagram of the inventive control device SG with connected components. The control unit SG is arranged in a vehicle FZ. Possible is a central arrangement, for example on the vehicle tunnel, but also other installation locations are possible. The control unit SG has a first interface IF1, which in the present case is designed as an integrated circuit and preferably may be part of a system ASIC. This first interface IF1 is used to connect an impact sensor AS, which is located outside of the control unit SG. The impact sensor AS includes, for example, an acceleration sensor and / or an air pressure sensor and / or a structure-borne sound sensor. An environment sensor is also possible. The transmission of the data, usually digitally from the impact sensor AS to the interface IF1, can take place via a current interface. Also an analog transmission is possible. In this case, a point-to-point and / or bus connection can be used. It is possible that the impact sensor is partly also within the control unit SG, in which case, for example, the microcontroller .mu.C itself has an interface as a software module or else as a hardware module.

At a second interface IF2 are wheel speed sensors RZ1 to 4 connected. This connection can also be used, for example, as a CAN connection be pronounced to a vehicle dynamics control unit, which in turn the wheel speeds by means of appropriate sensors detected. A sensor control device is possible in the present case. It is possible that the interface IS2 as digital Date the wheel speed and / or speed transmitted becomes. Other derived sizes are possible.

The Interface IS1 provides the signal of the impact sensor AS Collision detection module K on the microcontroller μC ready as evaluation circuit. In dependence of this Signal determines the collision detection module, whether a collision occurred or not. For this the technology of a usual Evaluation algorithm for the activation of personal protection devices used, usually with an adaptive threshold. If a collision has been detected by the collision detection module K, then a switch S is actuated, usually a software switch to activate the yaw motion detection module G. The yaw motion detection module G processes the signals of the wheel speed sensors, which gets this module provided by the interface IF2. From these signals, the yaw motion detection module determines the the yawing characterizing parameters such as a rate of rotation and the direction of rotation.

With the yaw motion and the collision signal are in the collision detection module AO the impact location determined. This impact location goes into the control module On a. Furthermore, depending on the yawing motion and the collision signal in the classification module KL, in which class the present collision is to classify. This class is also transmitted to the drive module AN. In order to can then the drive module AN as the last module presented here of the microcontroller μC determine if, which and how the appropriate personal protective equipment are to be controlled. this will then, for example, software and hardware transferred to the control circuit FLIC, which is also part of the system ASIC. The drive circuit FLIC outputs then a control signal to the personal protection FR from, For example, in this case, a vehicle dynamics control to the vehicle stabilize accordingly after the collision, making it suitable for Following collisions is better prepared. The drive circuit FLIC is at an output of a drive signal for a vehicle dynamics control preferably an interface for data transmission, for example a CAN transceiver or another bus controller.

It The following distribution is possible: The airbag control unit detects the direction of the collision and the corresponding severity this collision. These data (direction and severity) become a control device transmitted to the vehicle dynamics control, the yaw movement recognizes by the wheel speeds. Based on these measurements then initiated vehicle stabilization measures. It is possible, both functions airbag control unit and vehicle dynamics control unit to merge on a controller.

consequently is using the method according to the invention the direction and, if necessary, the strength of a yawing motion of the vehicle after a collision based on the wheel speed information determined. As shown above, first with the help of the impact sensor the presence of a collision detected. If there is a collision, The wheel speeds of the left and right side of the vehicle with each other compared. Take the wheel speeds on the left relatively to the on the right during the collision and immediately thereafter, the collision caused a rotation of the Vehicle in a clockwise direction.

It can be useful for the wheel speed comparison, the speeds of the front and rear wheels of a page and the To compare means of both sides.

For the wheel speed comparison is also useful, the speeds the wheels of the non-driven axle.

Farther it is useful for the wheel speed comparison, the wheel speeds influencing factors such as drive torques or braking torques during to suppress the yaw motion detection.

Based on the sign of the of impact sensor measured acceleration can be distinguished whether the vehicle was hit from the left or from the right.

Together with the information about the evoked direction of the Yaw movement can thus be closed to the location of the impact location become.

Has been for example, the vehicle hit from the left (negative lateral acceleration) and the yaw rate is also negative (clockwise), then the vehicle was hit in front of the center of gravity.

In 1 a vehicle FZ1 is shown, which is hit in the rear left of another vehicle FZ2 with the speed VK. Due to the forces acting the vehicle FZ1 is struck in a rotation about the vertical axis with the angular velocity Ψ. The lateral acceleration ay, which is measured by the impact sensor, is so great that the yaw rate sensor is disturbed in its function and thus can not provide information about the rotation of the vehicle during the collision. The yaw acceleration is negative in the example shown, so that it can be concluded that the vehicle was hit from the left.

drawn are also arrows for the wheel speeds, their length stands for the size of the speed. Due to the counterclockwise rotation, the wheel speeds are smaller on the left side of the vehicle than on the right side of the vehicle, which is detected by means of the wheel speed sensors of the vehicle dynamics system can be.

Out the fact that the vehicle was hit from the left and that the counterclockwise rotation can take place from the Evaluation circuit μC be concluded that the vehicle was hit behind the center of gravity. This information can be, for example for the selection of the means of retention to be triggered be beneficial.

About that In addition, the determined information about the direction of rotation used to perform a stabilizing braking intervention become. Thus, in the example shown, immediately after the determination the direction of rotation the front right wheel for a braking intervention be selected, which counteracts the yawing motion. A conventional vehicle dynamics system could be one Do not perform intervention because the required Yaw rate sensor signal disturbed by the collision forces is.

3 shows in a flow chart the inventive method. In the process step 300 a collision is detected on the basis of the signal of the impact sensor system AS, for example by means of a known triggering algorithm for personal protective equipment. Subsequently, in process step 301 then the switch S is actuated to activate the yaw motion detection module so that the yaw motion is determined from this module. The yawing motion is then in the process step 302 determined from the signals of the wheel speeds. In the process step 303 is determined from the collision signal and the yaw movement of the impact location and in the process step 304 From this data, including the impact location, a classification of the collision process is made. In the process step 305 then takes place the control of the personal protection means such as a vehicle dynamics control function of the classification and / or the impact location. Such data as the classification and the yaw movement can also be output, for example, to be used by a vehicle dynamics control unit for driving the vehicle dynamics control.

4 shows in a speed time diagram a typical course for the wheel speed speeds of the two sides of the vehicle. The curve 400 shows the wheels of the right side, and the curve 401 the left side of the vehicle. It can be clearly seen that the left wheels slow down and the right wheels are accelerated. In the area in which there is a clear and measurable difference between the wheel speeds on both sides of the vehicle, the collision forces act. Thus, the direction of rotation of the vehicle is still determined during the action of the collision forces and a targeted introduction of countermeasures such as the control of a vehicle dynamics control possible.

QUOTES INCLUDE IN THE DESCRIPTION

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Cited patent literature

• DE 102006007987 A1 [0002]

Claims (10)

Method for controlling personal protective equipment (FR) for a vehicle (FZ) with the following procedural steps: - Detect a collision depending on at least a first Signal of an impact sensor (AS), - Determine a Yawing by means of a wheel speed sensor (RZ1-4) depending on the collision; - Drive the personal protection device (FR) depending on the yaw movement. Method according to claim 1, characterized in that that a point of impact depending on the yawing motion Lind the at least a first signal is determined, the Personal protective equipment (FR) depending on the impact location be controlled. Method according to claim 1 or 2, characterized that depending on the first signal and on the Yaw movement is a classification of the collision, the Control is performed depending on the classification. Method according to one of the preceding claims, characterized in that based on a sign of the first Signal in a direction of impact and by comparison of the Wheel speeds is closed in one direction, the Control depending on the direction of impact and from the direction of rotation. Method according to one of the preceding claims, characterized in that in each case second signals of the wheel speed sensors averaged each side of a vehicle and resulting averages compared with each other to determine the yawing motion. Method according to one of the preceding claims, characterized in that as the personal protection means a driving dynamics control (FR) is controlled. Control unit (SG) for the activation of personal protective equipment (FR) for a vehicle (FZ) with: - a first one Interface (IF1), the at least one first signal of an impact sensor (AS) provides A second interface (IF2), providing at least one second signal to a wheel speed sensor, - One Evaluation circuit (μC) with a collision detection module (K), which depends on the at least one first Signal detects a collision, with a yawing module (G), depending on the at least one second signal detects a yawing motion, with a switch (S) for activation of the yawing module (G) is provided, depending on is pressed by the collision, - One Control circuit (FLIC), which depends on the Yaw movement which activates personal protective equipment (FR). Control device according to Claim 7, characterized the evaluation circuit (.mu.C) is an impact detection module (AO), which depends on the yawing motion and the at least one first signal determines the impact location, so that the drive circuit the personal protection (FR) depending from the impact site. Control device according to Claim 7 or 8, characterized the evaluation circuit (.mu.C) is a classification module (KL), which depends on the at least one first signal and classified by the yaw motion the collision, so in that the drive circuit (FLIC) depends on Classification of personal protective equipment (FR). Control device according to one of the claims 7 to 9, characterized in that the drive circuit (FLIC) a drive signal for a vehicle dynamics control as the Personal Protection (FR) issues.