EP1392532A1

EP1392532A1 - Method and device for dynamic setting of a vehicle component

Info

Publication number: EP1392532A1
Application number: EP02708358A
Authority: EP
Inventors: Peter Frank; Klaus-Peter Kuhn; Andreas Proettel
Original assignee: DaimlerChrysler AG
Current assignee: Daimler AG
Priority date: 2001-06-07
Filing date: 2002-03-20
Publication date: 2004-03-03
Also published as: WO2002098685A1; DE10127619A1; JP2004532155A; US20040167678A1; US7012513B2

Abstract

The invention relates to a method and device for dynamic setting of a vehicle component (P), in which a parameter which affects the behaviour of the vehicle component may be manually or automatically altered during driving. A state parameter (Z) which characterises the behaviour of the driver is then determined in direct connection with a change in the above parameter and said state parameter (Z) then compared with a set parameter (Z SOLL). The change in the parameter for the vehicle component (P) may be at least partly reset when the state parameter (Z) exceeds the set parameter (Z SOLL).

Description

Method and device for dynamic adjustment of a

vehicle component

11. The invention relates to a method and a device for the dynamic adjustment of a vehicle component according to the preamble of claims 1 and 11, respectively.

From the document DE 39 16 460 C2 a method for chassis control of passenger and commercial vehicles is known, in which an actuator arranged between the vehicle body and the wheels via control signals from a controller as a function of measurement signals via which the vertical and / or transverse dynamics of the Vehicle is determined, is to be set. Depending on the current driving state of the vehicle, different controller parameters can be specified, wherein setting options between a comfort-oriented and a driving safety-oriented vehicle behavior are possible. If critical driving conditions occur, which can be detected, for example, using the longitudinal tire forces and lateral tire forces, there is a transition to a safety-oriented design of the controller parameters.

With this method, there is a risk that if the controller parameters change automatically, the driver will be surprised by the changed driving behavior of the vehicle and that a dangerous situation arises due to an overreaction by the driver.

From document DE 44 19 317 AI a vehicle length system is known in which by using a neural network The driving experience of the vehicle driver is estimated and classified based on current vehicle measured values, controller parameters being adapted as a function of the driving experience. According to this document, it is proposed to reduce the assisting steering reaction torque if the driver is an experienced driver and to increase the steering reaction torque in the case of an inexperienced driver.

In the system described in DE 44 19 317 AI, the driver's steering behavior is influenced by increasing or decreasing the steering assistance as a function of the estimated driving experience. In this way it is possible to compensate for excessive reactions from inexperienced drivers who have a direct effect on the steering movement; beyond this, however, no further overreactions by the driver can be compensated for.

The invention is based on the problem of increasing driving safety in vehicles with a dynamic setting of at least one vehicle component, via which the driving behavior can be influenced.

This problem is solved according to the invention with the features of claims 1 and 11, respectively.

In the method according to the invention, a vehicle state variable which characterizes the driving behavior of the vehicle driver, for example the steering angle or variables correlating therewith, in particular the steering angle speed, is determined immediately after a change in a parameter determining the behavior of the vehicle component. This state variable, which characterizes the driving behavior, is compared with a predetermined target variable. If the status large exceeds the target size, the change in the vehicle component is at least partially reversed.

In contrast to the prior art, this method deals directly with the cause of an overreaction by the driver, namely the change in the behavior of the vehicle component, in that this change is at least partially returned to the original state or at least a softened state. It is therefore not absolutely necessary to change the steering behavior of the vehicle, the changes of which are usually perceived by the driver as particularly serious, such automatic changes again being the cause of undesirable and dangerous driver reactions. Rather, the cause of the exaggerated driver reaction is at least partially compensated for by the readjustment with the controller components at the affected vehicle component being softened or reset to their original state.

The state variable that can be influenced by the driver is examined over a predetermined period of time immediately following the change in the vehicle component or the characteristic variable of the vehicle component, in particular the amplitude, frequency and / or degree of damping of this state variable being determined within the period under consideration and at least one of these variables is compared with an assigned setpoint. For example, it can be expedient to determine the number of vibrations whose amplitude exceeds a minimum value within the period under consideration, the change in the parameter of the vehicle component being withdrawn in the event that the number of these vibrations is greater than a desired number of vibrations. In relation to the steering angle as the state variable to be examined and influenced by the driver, this means that violent steering movements of the driver, consisting of deflections in one direction and compensating counter-movements opposite direction, the assessment for the withdrawal of the change in the parameter in the affected vehicle component. The change is canceled in the event that the driver executes steering movements several times in succession, the amplitude of which is above a limit value.

In addition or as an alternative to considering the steering angle or the correlating variables, it may also be appropriate to determine the vehicle lateral acceleration and to base the assessment on the retention or withdrawal of the change or changeover in the parameter of the component.

If the evaluation shows that a withdrawal of the change is indicated, this can be done in several graded steps, the change being only partially withdrawn first and a stronger withdrawal taking place from step to step. In a first step, the changeover phase is advantageously first extended, within which a change in the parameter of the vehicle component is carried out, so that instead of an abrupt change there is a continuous change, which gives the driver the opportunity to get used to the change.

If it is determined in a renewed measurement and calculation cycle that despite the withdrawal made in the first step, the driver's reactions are still above the permitted level, in a second step the permissible range of variation for the change in the affected parameter can be reduced, so that this too Behavior of the vehicle compared to the original state is modified to a lesser extent. The second step is advantageously combined with the first step. If it is determined in a further measurement and calculation cycle that the driver's reactions are still outside the permitted target range, the change in the parameter can be completely withdrawn in a third step and the parameter can be frozen to its original value. The third step is also advantageously combined with the previous step, possibly with both previous steps.

If the parameter has been kept at the currently set, reset value for a minimum period of time, the parameter can be changed over manually or automatically, or the value of the parameter that was valid before the last change is reset.

Both a parameter of this component and a state variable can be considered as the characteristic value of the vehicle component to be influenced. In the event that the vehicle component under consideration is a spring element, it may be expedient to change the spring rate as a parameter, whereas the spring travel is influenced as a state variable, which can be achieved, for example, by replacing the spring with an actively controlled actuator ,

The device according to the invention for the dynamic adjustment of the vehicle component, the characteristic of which can be changed automatically or manually by actuation via an actuator during the journey, comprises a regulating and control unit in which actuating signals can be generated from sensor-determined measurement signals of the vehicle in accordance with a stored calculation rule which Actuator for setting the vehicle component are supplied. One of the measurement signals corresponds to a vehicle state variable representing the behavior of the driver. This measurement signal is in a comparison unit of the control and the control unit is compared with a given target variable, wherein in the event that the measurement signal exceeds the target variable, a control signal to be supplied to the actuator is generated, with which the change in the parameter of the vehicle component is at least partially reversed.

The vehicle component, which influences the driving behavior of the vehicle, is in particular the vehicle brake, steering assistance, engine control, drive train control and / or the spring-damper system in the vehicle.

Further advantages and expedient designs can be found in the further claims, the description of the figures and the drawing, in which a flow chart with the individual steps of the method is shown.

According to method step 1 a determining parameter is either vehicle component but _{automatically} switches a manually by the driver or due to changes in external conditions, from an initial value P _org in a new value P. The switchover is carried out, for example, by loading the vehicle component via an actuator, which changes the operating behavior of this vehicle component. The setting via the actuator can take place, for example, in a regulating and control unit by means of stored characteristic curves or the calculation of actuating signals.

In the following method step 2, a vehicle status variable Z is determined, in particular by measurement, but possibly also by mathematical determination from a measurement variable, this vehicle status variable Z characterizing the driving behavior of the vehicle driver. The steering angle or a variable correlating therewith is determined as such a state variable. if necessary, however, In addition or alternatively, the vehicle lateral acceleration or another variable, the course of which allows conclusions to be drawn about the driving behavior of the vehicle driver.

In the following method step 3, a check is made in the regulating and control unit of the system as to whether the measured vehicle state variable Z exceeds an assigned target variable Z _so . If this is not the case, it can be concluded that the parameter switchover from P _org to P _new does not result in a negative change in the driving behavior of the vehicle driver. In this case, the No branch is returned accordingly at the start of the procedure.

If the measured vehicle state variable Z _thus exceeds the assigned target value Z, it can be concluded that the vehicle driver is overreacting, which can lead to dangerous driving situations. In this case, the yes branch is continued in accordance with the following method step 4, in which the parameter switchover is at least gradually withdrawn.

The query according to method step 3 can be run through cyclically at regular intervals in order to have permanent control over the driving behavior of the vehicle driver. In method step 3, the vehicle state variable Z measured over a minimum period of time is examined in particular. For this purpose, determining parameters of the vibration profile of the vehicle state variable Z are expediently determined, in particular the amplitude, the frequency and the degree of damping within the period under consideration. If one or more Z is these parameters over associated nominal sizes _so ιι can be assumed that an over-reaction of the driver. For example, the number of vibrations is determined, the amplitude of which exceeds a minimum value. Provided the number of these vibrations is above a permissible limit value, the condition according to method step 3 is fulfilled and the method continues to method step 4, in which the parameter switchover is gradually withdrawn.

As shown in method step 4, the parameter changeover is advantageously canceled in three stages. In a first stage, the duration of the switchover phase is first extended, so that the change in the determining parameter, via which the behavior of the vehicle component is decisively determined, is _now slower from P _org to P than was initially carried out in method step 1. The rate of change for the parameter is reduced, so that the vehicle driver has a longer period in which he can get used to the changed driving behavior.

During the switchover phase and also after the switchover phase in accordance with the first stage, the vehicle state variable Z is continuously measured at cyclical intervals and checked for exceeding the assigned target value Z _so . If the setpoint is still exceeded during the switchover phase or after the switchover phase of the first stage, the second stage is advanced according to which the permissible variation range for the parameter is reduced. The range of variation can be characterized by ΔP, which is added to the original parameter value P _org , so that the new parameter value P is _new according to the relationship

Pneu ~ org T ^" ΔP

calculated. The variation range .DELTA.P is reduced in the second stage compared to a basic setting, so that a smaller change in the parameter is carried out than in the Basic setting is the case. Even during and after the second stage, the vehicle condition variable Z is continuously measured and checked for exceeding the setpoint.

If it is determined in spite of the reduction in the second stage still exceeded, the operation proceeds to the third stage, in which the parameter switching is completely withdrawn and the current value of the parameter switching P is _reset to the initial value P _org, the basic setup of this Parameters.

Subsequent to both the first stage and the second stage and the third stage, a waiting time t _Ha ιt is waited for in accordance with the following method step 5, in which the vehicle state variable Z is measured and checked for exceeding the target variable Z _so . If the target value Z _so n is not exceeded within the holding time t _Ha ιt, after the holding time t _Ha ιt has expired, the withdrawal of the parameter switchover carried out in method step 4 is canceled again and the current parameter value is set to the value set before the withdrawal. Subsequently, step 1 is returned to.

Claims

claims

1. A method for the dynamic setting of a vehicle component, in which a parameter influencing the behavior of the vehicle component can be changed automatically or manually during the journey, characterized in that, immediately after a change in the parameter of the vehicle component, a vehicle state variable characterizing the behavior of the driver is determined is that the state variable characterizing the driver behavior is compared with a target quantity, the change in the characteristic quantity of the vehicle component being at least partially reversed if the state variable exceeds the assigned target quantity.

2. The method according to claim 1, wherein the steering angle is determined as the state variable that can be influenced by the behavior of the driver.

3. The method according to claim 1 or 2, characterized in that the vehicle lateral acceleration is determined as a state variable which can be influenced by the behavior of the driver.

4. The method according to any one of claims 1 to 3, that the amplitude and / or the frequency and / or the degree of damping of the state variable which can be influenced by the driver is determined and the comparison with an assigned target variable is used as a basis.

5. The method as claimed in claim 4, so that the number of vibrations, the amplitude of which exceeds a minimum value, must be greater than a predetermined desired number of vibrations for the change in the parameter of the vehicle component to be canceled.

6. The method according to any one of claims 1 to 5, characterized in that the withdrawal of the change in the parameter of the vehicle component is carried out in several stages, wherein after each withdrawal determines the state variable characterizing the driver behavior, compared with the assigned target quantity and in the event of over or If the target value is undershot, a further withdrawal is carried out.

7. The method according to claim 6, characterized in that, in a first stage of withdrawal, the switchover phase for changing the characteristic variable is initially extended in time becomes.

8. The method according to claim 6 or 7, so that in a second stage of withdrawal, the range of variation in which the change in the characteristic variable is permitted is reduced.

9. The method according to any one of claims 6 to 8, so that in a third stage of the withdrawal, the parameter is set to a standard value corresponding to the series vote.

10. The method according to any one of claims 1 to 9, so that the withdrawal is canceled after a predetermined period of time and the parameter is set to the value existing before the withdrawal.

11. Device for dynamic adjustment of a vehicle component, in particular device for performing the method according to one of claims 1 to 10, the behavior of which is to be influenced by a characteristic variable, the characteristic variable being able to be changed automatically or manually while driving via an actuator which uses control signals can be set, which can be generated in a regulating and control unit according to a stored calculation rule from sensor-determined measurement signals, characterized in that, immediately following an actuation of the actuator, a measurement signal can be determined which corresponds to a vehicle state variable representing the behavior of the driver, and that the measurement signal in a comparison unit of the regulating and control unit is comparable to a target variable, one of which is the actuator supplyable, the change in the characteristic of the vehicle component at least partially reversing control signal can be generated if the state variable exceeds the assigned target variable.

12. The apparatus of claim 11, d a d u r c h g e k e n n z e i c h n e t that the vehicle component influencing the driving behavior is the vehicle brake, the steering support, the drive train control and / or the spring-damper system in the vehicle.