EP1406800A1

EP1406800A1 - System and method for monitoring the performance of a vehicle

Info

Publication number: EP1406800A1
Application number: EP02758070A
Authority: EP
Inventors: Manfred Gerdes
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2001-07-04
Filing date: 2002-07-02
Publication date: 2004-04-14
Also published as: US7079930B2; DE10132440A1; JP2004521023A; WO2003004330A1; US20040030477A1

Abstract

The invention relates to a system for monitoring the performance of a vehicle which comprises a plurality individual systems (12, 14, 16) for influencing the performance of a vehicle. A management device (10) is provided for managing the influences of the performance by said individual systems (12, 14, 16). The invention also relates to a method for monitoring the performance of a vehicle.

Description

System and method for monitoring the driving behavior of a vehicle

The invention relates to a system for monitoring the driving behavior of a vehicle with several individual systems for influencing the driving behavior of the vehicle. The invention further relates to a method for monitoring the driving behavior of a vehicle, in which the driving behavior of the vehicle is influenced by means of several individual systems.

State of the art

Generic systems and generic methods serve in particular to stabilize the driving behavior of motor vehicles. There are already several different systems that work on the basis of different measurement variables and by influencing different parameters that affect the driving behavior of the vehicle. Examples of such systems, which are also referred to as driving dynamics controls, are the electronic stability program (ESP), the "active body control" (ABC), a chassis control with superimposed stabilizing intervention (EAR), a Vordera.ch.s- steering with superimposed stabilizing intervention (EAS) or a rear axle steering.

Since several of these individual systems can be installed in the same vehicle, it is possible that the stabilizing interventions of the individual systems overlap in their effect. Thus, multi-size control is a typical problem. The interventions of the different individual systems can overlap positively and in this way lead to excessive interventions; in other words: there are several redundant interventions. It is also possible for a negative overlay to take place, so that ultimately there is insufficient intervention in driving stability. A positive overlay of the interventions primarily leads to an undesirable impairment of driving comfort. If the interventions are superimposed negatively, the driving dynamics regulations sometimes fail to work, which is particularly a problem with regard to driving safety.

In order to suppress the disturbances in the control interventions between the individual systems, it has already been proposed that signals be exchanged in a targeted manner between the individual systems or that critical functional areas in individual systems be excluded. This can lead to a coexistence of the systems in which the effects of the systems do not have a negative impact. The total benefit of the entire network system can thus remain as great as the sum of the individual benefits of the subsystems. Advantages of the invention

The invention is based on the generic system in that a management device is provided for managing the influencing of driving behavior by the individual systems. Through targeted management of the stabilization functions of the individual functions, it becomes possible that the total benefit is greater than the sum of the individual benefits. This can be done in such a way that the management device influences the effects of the individual systems depending on the situation. Thus, driving stability is maintained with the greatest possible driving comfort and minimal loss of speed. In this way, the individual systems can in principle act completely independently of one another; That means: the individual systems are independent of each other without any intervention by the management facility. Only if the individual systems could be influenced in an undesirable manner can the management device intervene. In this context, it is particularly advantageous that if the management device fails, it can be ensured that the individual systems continue to exert their stabilizing effects, which is particularly useful with regard to driving safety. The subsystems can also be developed and applied separately.

In particularly preferred systems, as individual systems

^" ESP, EAS, EAR and / or ABC can be provided. These are exemplary single systems without single limitation of the generality of the present invention, which may include any individual systems.

In a particularly preferred embodiment, the system is further developed in that the management device is implemented in a control unit which communicates with control units of the individual systems via an interface. Such an interface can be implemented, for example, in the context of a CAN system. The management device can receive information about the activity of the individual systems via CAN or another interface. This information can either be formulated directly as an effective moment around the vertical axis on the vehicle's center of gravity or a force on the vehicle's center of gravity. It can also be shown as an average, which is converted in the management facility on a torque basis. Conversely, the control units of the individual systems receive information from the management device via the interface, that is to say for example via CAN, so that the effects of the individual systems are influenced.

In a preferred embodiment, the management device is implemented in a separate control device. With regard to the hardware, the management device is therefore independent of the control units of the individual systems. The systems can therefore be developed and applied independently of one another.

However, it can also be useful for the management device to be implemented in one or more control units) of the individual systems. The control units of the individual Systems are hardware components that are available anyway. By implementing the management device within these control units of the individual systems, the hardware effort can be reduced.

In a particularly preferred embodiment of the method according to the invention, this is further developed in that actual values and target values determined by the individual systems are entered into the management device, the potential effects of the individual systems are determined from the entered values and that values can be output by the management device, that affect the effects of individual systems. The management facility thus acts preventively on any undesired interventions. The setpoints, which are determined by the individual systems, are recorded by the management device and coordinated with one another taking into account the actual values assigned to the corresponding variables. Values can thus be output by the management device, so that the effects of the individual systems are sensibly adapted.

In this context, it is particularly advantageous to note that the management device can suppress interventions by individual systems. In this variant, the individual systems work completely independently of one another if no intervention is carried out by the management. This has advantages, for example, in the event of a management device failure. The individual systems are then still fully functional. Only if interventions by individual systems are to be suppressed, will the management establishment made. For example, the transmission of an acknowledgment signal may be sufficient. This indicates whether the stabilizing intervention proposed by the individual system should be suppressed. For example, a symbolic digital 1 for suppression or a symbolic digital 0 or no signal transmission can be used to fully implement the stabilizing intervention.

The invention builds on the generic method in that a management device is provided for managing the influencing of driving behavior by the individual systems. In this way, the advantages of the system according to the invention are implemented in the method. In the embodiments of the method specified below, the advantages and special features of the corresponding system designs are also noted.

In particularly preferred processes, ESP, EAS, EAR and / or ABC can be provided as individual systems.

In a particularly preferred embodiment, the method is further developed in that the management device is implemented in a control unit which communicates with control units of the individual systems via an interface.

In a preferred embodiment, the management device is implemented in a separate control device. However, it can also be useful for the management device to be implemented in one or more control units of the individual systems.

In a particularly preferred embodiment of the method according to the invention, this is further developed in that actual values and target values determined by the individual systems are entered into the management device, the potential effects of the individual systems are determined from the entered values, and values can be output by the management device that the Influence the effects of individual systems.

In this context, it is particularly advantageous to note that interventions by individual systems can be suppressed by the management device.

The invention is based on the knowledge that through targeted management of the stabilization functions of individual systems, the total benefit of the systems can be greater than the sum of the individual benefits. This can be done, for example, by masking out interfering interventions depending on the situation, while meaningful interventions are specifically permitted together. The subsystems can be developed and applied independently of one another, only the possibility of an exchange of information having to be ensured. Any expansion stages can also be implemented within a vehicle range. The correct handling of the interfaces in all control units involved must be observed. For the joint operation of all individual systems In this way, the development and application of the management facility is decisive in the vehicle.

drawings

The invention will now be explained by way of example with reference to the accompanying drawings using preferred embodiments.

It shows:

FIG. 1 shows a block diagram to illustrate a system according to the invention;

FIG. 2 shows a block diagram to illustrate driving stability management;

FIG. 3 shows a μ slip curve for a tire model in the longitudinal direction of the tire;

FIG. 4 shows a μ slip curve for a tire model in the transverse direction of the tire;

Figure 5 is a diagram for explaining the angular relationships of the tire forces;

FIG. 6 shows a flowchart to explain a tire force calculation for bidirectional stress; FIG. 7 shows a flowchart to explain the calculation of a tire force and a change in tire force during a longitudinal ESP intervention;

FIG. 8 shows a flowchart to explain the calculation of a tire force and a change in tire force during an EAS lateral force intervention;

FIG. 9 is a diagram for explaining a vehicle model for calculating the torques around the

Vertical axis on the center of gravity;

FIG. 10 shows a flowchart to explain the calculation of moments on the vehicle center of gravity about the vertical axis;

FIG. 11 shows a flow chart to explain the calculation of a center of gravity moment by summation;

FIG. 12 shows a flow chart to explain the calculation of a center of gravity moment by summation in the case of ESP longitudinal force intervention;

FIG. 13 shows a flowchart to explain the calculation of a center of gravity moment by summation in the case of EAS lateral force intervention;

FIG. 14 shows a flowchart to explain the formation of engagement moments in ESP and EAS for an engagement assessment; and 10

FIG. 15 shows a flowchart to explain prioritization, evaluation and selection of stabilizing interventions.

Description of the embodiments

FIG. 1 shows a block diagram to illustrate a system according to the invention. The block diagram shows functional units and arrows that symbolize signals between the individual functional units. Individual signals are symbolized by arrows with a single line. Signal vectors are symbolized by arrows with several lines. Three individual systems 12, 14, 16 are given as examples. An ESP control unit 12, an EAS control unit 14 and an EAR control unit 16 each communicate via CAN 18 in accordance with the valid protocol agreement with a driving stability management control unit 10. The driving stability management control unit 10 is shown here as a separate control unit. It is also possible to utilize one of the existing control units 12, 14, 16 to a greater extent with the tasks of the driving stability management control unit 10. The control units 12, 14, 16 of the individual units transmit information to the driving stability management system - control unit 10, that is to say in particular values which have an influence on the driving dynamics for intended interventions. The driving stability management control unit 10 in turn transfers values a to the control units 12, 14, 16 of the individual systems, for example a 0 for releasing the effect of the control units 12, 14, 16 of the individual systems and a 1 for blocking the respective effects. The- Its effects include, for example, influencing a brake system 20, a steering system 22 or a chassis 24 via corresponding actuators 26.

FIG. 2 shows a block diagram to illustrate driving stability management. The block diagram shows functional units and arrows that symbolize signals between the individual functional units. Individual signals are symbolized by arrows with a single line. Signal vectors are symbolized by arrows with several lines. Various values are transferred to the driving stability management via the input 28 of a CAN interface. These values are, for example, a stabilizing target wheel slip by ESP 40 and a superimposed steering angle on the front axle for stabilization by EAS 42. Furthermore, information from subsystems 44 is transferred. In particular, these can be the following variables: slip per wheel, vehicle speed, lateral acceleration, driver steering angle, steering angle on the wheel, accelerator pedal position, driver brake pressure, slip angle of the front or rear axle, wheel support force and coefficient of friction.

As a further variable, a differential torque on the vehicle's center of gravity around the vertical axis is transferred via input 28 of the CAN interface by means of a stabilizing chassis intervention by EAR 46.

The information 40, 42, 44 is a unit 32 for calculating the longitudinal and transverse force and their changes transferred to the vehicle tire from physical models of the tire characteristics. From the calculation in unit 32, information regarding the tire longitudinal forces and their changes due to longitudinal intervention 48 and regarding the tire lateral forces and their changes due to lateral force intervention 50 follow. The information 48 is provided to a unit 34 for calculation of moments and their changes around the vertical axis the vehicle's center of gravity due to an ESP intervention. The information 50 is transferred to a unit 36 for calculating moments and their changes about the vertical axis on the center of gravity of the vehicle due to an EAS intervention. The output variable of the unit 34 is a differential torque on the vehicle center of gravity around the vertical axis by means of a stabilizing brake intervention 52. The output information of the unit 36 is a differential torque on the vehicle center of gravity around the vertical axis by means of a stabilizing front axle steering intervention 54. The latter information 52, 54 are transferred to a unit for prioritizing, evaluating and selecting stabilizing interventions 38. The output variables of the unit 38 are instructions for suppressing a longitudinal force intervention 56, a lateral force intervention 58 or a normal force intervention 60, which are output as a function of the results of the unit 38 via the output of the CAN interface 30.

The differential torque on the center of gravity around the vertical axis through a stabilizing chassis intervention by EAR

^" 46 is assigned directly to the unit 38 for prioritizing, evaluating input and selection of stabilizing interventions and taken into account by them.

In summary, in the unit according to FIG. 2, the incoming signals, possibly converted to a torque based on the vertical axis of the vehicle on the center of gravity, are interpreted as a driving stability intervention, summed up, weighted and compared. Furthermore, the intervention (s) to be suppressed is selected and reported back. As an example, it is assumed in the illustration according to FIG. 2 that the ESP transmits the superimposed target slip for each wheel as a characteristic variable for the intervention in driving stability. Other or different sizes are conceivable and possible. With the EAΞ it was assumed that the superimposed steering angle, which is supposed to have a stabilizing effect on the vehicle, serves as the transfer size. Other or different sizes are conceivable and possible. At the EAR. It was assumed that the stabilizing moment on the vehicle's center of gravity with respect to the vertical axis was determined and transmitted directly in the EAR control unit on the basis of the desired or planned confirmation of the EAR actuator system there, and is therefore directly available in the drive management control unit. Here, too, other or different sizes are conceivable and possible.

FIG. 3 shows a μ slip curve for a tire model in the longitudinal direction of the tire. Schematic tire characteristic curves in the longitudinal direction and a possible approximation depending on the longitudinal tire slip and road surface friction are given, the set parameters and these characteristic curves being examples of many possible ones 1 Δ

Realizations of the connection between tire longitudinal force, tire longitudinal slip and road surface friction are available. The longitudinal wheel force μ is plotted on the vertical axis, which is defined as

- ^F Rad / ^F N

that is, as the quotient of the longitudinal wheel force and normal wheel force. The slip Sl is plotted on the vertical axis. The following equations are used to approximate the longitudinal forces:

u = _A / (a _x ² + a _y ² ) / g

where: g = 9.81 m / s ²

a _κ , a _y : acceleration in the longitudinal or transverse direction.

Since there are no signals for the above calculation of the used coefficient of friction when driving in the longitudinal and transverse directions without acceleration, a coefficient of friction μ = 0.0 would be specified in this case. In order to rule out problems with such zero values, the value range of the coefficient of friction is limited to μ _Min = 0.1. For example, μ ^., = 1.0 can be used as the upper limit. A limitation to higher values would also be conceivable.

The characteristic values for the approximation of the longitudinal forces are calculated as follows, where Kl 'denotes a force gradient and the specified numerical values can preferably be set: 15

Sl '(μ) «0.04 + 0.08 * μ Kl ¹ (μ) * 1.00 + 12, 0 * μ

Sl '' «0.70 ϊ

The actual approximation of the longitudinal forces using Sl as input information is then carried out for Sl <Sl '(μ) according to the relationship:

F _L = Fn * Kl '(μ) * Sl.

Otherwise, the longitudinal force F _{L is determined} according to the following relationship:

F _L = Fn * Kl '(μ) * Sl' * (Sl '+ Sl'') / (Sl + Sl'').

The second type of calculation of F _L takes into account the drop in the characteristic curve in the event of high slip Sl.

In connection with the above calculations, it should be noted that the coefficient of friction is related to the center of gravity of the vehicle. As a result, unequal friction coefficients on the right or left side of the vehicle are taken into account by averaging.

FIG. 4 shows a μ slip curve for a tire model in the transverse direction of the tire. The wheel side force is plotted on the vertical axis of the diagram, which as

μ = F _SRad / F. HRad is defined, i.e. as the quotient of the wheel lateral force and the wheel normal force.

The slip parameter α is plotted on the right axis of the diagram.

To determine the coefficient of friction information, reference is made to the explanations relating to FIG. 3.

The setting parameters can be determined on the basis of the following equations, the numerical values here also preferably being adjustable:

α '(μ) «0.80 + 4.00 * μ ks' (μ)» 0.11 + 0.17 * μ ¹ ' «30 °

The actual approximation then takes place according to the following equations, a distinction being made between two cases. In the first case, α <α ¹ (μ). The lateral force is then calculated using the following equation:

F _s (μ, α) = ks' (μ) * α * F „.

In other cases, the lateral force is calculated using the following equation:

F _s (μ, α) = ks' (μ) * α ¹ * F _N * ( ¹ + α ") / (α + α"). In the second case, the drop in lateral force is taken into account at high values of α.

With small values of α, the following approximation can still be carried out:

F _s (μ, α) s s'lμ) * Fn * δ = ΔF _E (μ) * δ.

With regard to the unequal friction values between the right and left side of the vehicle, reference is again made to the explanations for FIG. 3.

FIG. 5 shows a diagram to explain the angular relationships of the tire forces. The tire longitudinal forces F _L (Sl, μ, F ") and F _s (, μ, F _H ) of the tire 70, which are determined by the coefficient of friction μ and the longitudinal slip Sl taking advantage of the coefficient of friction μ, or by the coefficient of friction μ and the tire slip α are determined, add up quadratically to the total tire force

F _R (λ, μ, F _N ) = (F _S (α, μ, F _N ) ² + F _L (S1, μ, F _N ) ^<

Assuming that the tire characteristics in the longitudinal and transverse directions are in the linear range, that is to say there is little slip and small slip, slip and slip can be entered in FIG. 5 in the manner shown. In this way, the slip δ can be obtained from slip Sl and slip α _Ξ1

tan (δ) = F _s / F _L = α _sl / Sl dεfiniεren. Because of the nonlinearities that occur, this relationship is not exactly correct for large values of slip and slip, but its quality is sufficient for the estimation necessary in many applications.

In this way, a vehicle longitudinal force F _L can be estimated from a predetermined wheel force F _R

F _L = F _R * Sl / λ

and the tire lateral force F _s

These equations can be realized relatively easily with the longitudinal slip equivalents λ entered in FIG. 5, zero divisions having to be treated separately.

On the basis of the tire force models, which were explained with reference to FIGS. 4 and 5, the determination of the longitudinal force load and the lateral force load of a tire is possible in principle. However, the models mentioned assume a monodirectional force effect. The superimposition with bidirectional force effects must be treated separately. If an attempt is made to determine the longitudinal force and the lateral force separately and to superimpose them subsequently, the ambiguous assignment of the tire forces to the skew or slip due to the maximum of the curves at problematic effects arise in the force evaluation.

This can be avoided under the largely valid assumption of synergistic tire behavior in the longitudinal and transverse directions, for example by the following procedure:

The maximum transferable tire force is assumed to be μ * F _N.

The slip slip and the longitudinal slip are overlaid square to a longitudinal slip equivalent λ.

The course of this resulting tire force takes place from a similar characteristic curve model as was explained in connection with FIGS. 3 and 4.

The tire force is split into longitudinal force components and transverse force components on the basis of angular relationships, the splitting being based on the slip and the skew.

The tire forces are approximated using the following equations. The coefficient of friction information is in turn formed as explained with reference to FIG. 3.

The following characteristic values are used, whereby the numerical values are again adjustable: 20

P_K _λ l «0.80 [%]

P_K> 2 «4, 00 [%]

P_K _λ 3 «0, 11 [-]

P_K _λ 4 * 0.17 [-]

PK _λ 5 * 70.0 [%]

An approximation follows the following equations, divided into two cases:

λ '(μ) = P_K _λ l + P_K _λ 2 * μ k _λ (μ) = P_K _λ 3 + P_K _λ 4 * μ λ ¹ ' = PK _λ 5

First case: λ <λ '(μ)

In this case the lateral force is calculated according to the following equation:

F _s (μ, λ) = ks' (μ) * λ * Fn.

In the second case, i.e. λ> λ '(μ), the calculation is carried out as follows:

F _s (μ, λ) = k _λ '(μ) * λ' * Fn * (λ ¹ + λ '') / (λ + λ '').

The second case realizes a decrease in the lateral force at high values of the longitudinal slip equivalents λ. The conversion to the longitudinal force is then carried out according to the equation

F _L (μ, λ, Sl) = F _s (μ, λ) * Sl / λ.

This is converted to the shear force

F _L (μ, λ, Sl) = F _s (μ, λ) * α _sl / λ.

Regarding the explanations with regard to unequal coefficients of friction between the right and left side of the vehicle, reference is made to the explanations regarding FIG. 3.

FIG. 6 shows a flowchart to explain a tire force calculation for bidirectional stress. First, the meaning of the individual process steps is given.

3201: start

3202: P_K _λ l = 0.80 ... [%] parameter 1 for determining the

Location of the maximum

P_K _λ 2 = 4.00 ... [%] parameter 2 for determining the

Position of the maximum P_K _λ 3 = 0.11 ... [-] Parameter 3 for determining the

Slope from origin

P_K? .4 = 0.17 ... [-] Parameter 4 for determining the

Increase from origin

P_K _λ 5 = 70.0 ... [%] Parameter 5 for determining the drop at high values

P_K _θ31 = 100.5 / 45.0 ... [% / °] conversion factor from

Skew to slip 3203: α = α * _sl ... P_K _αsl conversion skew longitudinally - slipping equivalent λ = ^S _ORT ^(α _sι ^{2 +} S ^2} ... slip and longitudinal slip λ ¹ = add square P_K _ΛX P_K + ^ ₂ * μ. .. tire force maximum depending on longitudinal slip equivalents

Kχ = P_K _? , ₃ + P_K ^ ₄ * μ ... tire force gradient with respect to Origin of longitudinal slip equivalents λ '' _K ₅ ... def. Tire force drop from maximum with regard to longitudinal slip equivalents

3204: λ <λ '... longitudinal slip equivalents less than value at maximum tire force?

3205: F _R = F _N * K _λ * λ '* (λ ^{1 1} + λ') / (λ + λ '') ... total tire force from -maximum with regard to longitudinal slip equivalents

3206: F _R = F _N * K _λ * λ ... total tire force up to maximum with regard to longitudinal slip equivalent

3207: λ == 0 ... longitudinal slip equivalents equal to = 0.0?

3208: F _s = 0.0 ... tire lateral force

F _L = 0.0 ... longitudinal tire force ^"""

3209: F _s = F _R * α _sl / λ ... tire lateral force F _L = F _R * Sl / λ ... tire longitudinal force

3210: end After the start in step 3201, parameters for determining the tire force are set in step 3202. In step 3203, further quantities are calculated using the parameters from step 3202, which can be used in steps 3204 to 3210. In step 3204 it is first determined whether the longitudinal slip equivalent is less than the value at maximum tire force. If this is the case, then step

3206 the total tire force is calculated according to the relationship given there. If this is not the case, then in

Step 3205 uses another relationship given there to calculate the total tire force. In step

3207 is then checked to see if the longitudinal slip equivalent is zero. If this is the case, avoiding a division by zero, the lateral tire force F _s and the longitudinal tire force F _{L are set} to zero. If this is not the case, that is to say the longitudinal slip equivalents are not equal to zero, then the lateral tire force and the longitudinal tire force are calculated in accordance with the relationships given there. The method according to FIG. 6 ends in step 3210.

FIG. 7 shows a flowchart to explain the calculation of a tire force and a change in tire force during an ESP longitudinal force intervention. With regard to an ESP intervention, the skew angle on the front and rear axles is a known but predetermined size, it being possible to intervene in the wheel slip to vary the longitudinal force. The flow chart according to FIG. 7 shows the calculation of the current wheel forces and the wheel force changes due to the ESP intervention. This algorithm must be run for each bike. First, the meaning of the individual steps is given.

3211: start

3212: Sl = SlRad ... longitudinal slip of the wheel under consideration

3213: α = αRad ... skew angle of the wheel

3214: Calling up the tire force model as a function of Sl, α

3215: F _s wheel = F _s ... release lateral force F _L wheel = F _L ... release longitudinal force

3216: Sl = Sl + SlRadEsp ... longitudinal slip intervention for wheel

3217: Calling up the tire force model as a function of Sl, α

3218: ΔF _SESP Rad = F _Ξ Rad - F _s ... store the change in lateral force ΔF _LESP Rad = F _L Rad - F _L ... store the change in longitudinal force

3219: end

After the start of the calculation in step 3211, the slow slip of a wheel under consideration is determined in step 3212. Subsequently, the slip angle of the wheel is determined in step 3213. In step .3214, the tire force model is called up as a function of the determined parameters S1 and α. In step 3215, the determined the lateral force and the determined longitudinal force are stored as parameters F _s wheel or F _L wheel. In step 3216, the longitudinal slip intervention for the wheel is taken into account. In step 3217, the tire force part is again called up as a function of the new parameters S1 and. In step 3218, the change in lateral force and the change in longitudinal force are then determined and stored by means of differential formation. In step 3219, the calculation of the tire force for the wheel under consideration ends.

FIG. 8 shows a flowchart to explain the calculation of a tire force and a change in tire force during an EAS lateral force intervention. With regard to an EAS intervention, the wheel slip on the front axle and the rear axle is considered to be a known but predetermined size, which can be interfered with in the slip angle at least on the front axle for lateral force variation. The flow diagram according to FIG. 8 shows the calculation of the current wheel forces and the wheel force changes due to the EAS intervention. The slip angle intervention by EAS is stored individually for each wheel and is assigned zero for the rear wheels. As a result, the algorithm explained with reference to FIG. 8 can be run through equally for all wheels and thus also for vehicles with active rear axle steering with corresponding signal assignments. The algorithm explained below must be passed through for each wheel. First, the meaning of the process steps shown in FIG. 8 is shown.

3220: start 3221: Sl = SIRad ... longitudinal slip of the wheel under consideration

3222: α = αRad ... slip angle of the wheel

3223: Calling up the tire force model as a function of Sl, α

3224: F _Ξ Rad = F _s ... relieve lateral force F _L Rad = F _L ... relieve longitudinal force

3225: α = α + RadEas ... slow slip intervention of the wheel

3226: Call of the tire force model as a function of Sl, α

3227: ΔF _SEAS wheel = F _s wheel - F _s ... store lateral force change ΔF _LEAS wheel = F _L wheel - F _L ... store longitudinal force change

3228: end

In step 3220, the calculation of the tire force and the tire force change for the EAS longitudinal force intervention starts. In step 3221, the longitudinal slip of the wheel under consideration is stored as variable S1. In step 3222, the slip angle 1 of the wheel is stored as a variable. In step 3223 the tire force model is called up using the stored parameters S1 and α. The side force and the longitudinal force of the wheel are stored in step 3224. In step 3225, a slow slip intervention of the wheel is taken into account and a new variable α is stored. In Step 3226, in turn, calls up the tire force model as a function of the parameters S1 and α now present. Subsequently, a change in lateral force is calculated and stored in step 3227 by forming the difference. A change in the longitudinal force is also calculated by forming a difference and is subsequently stored. The method shown in FIG. 8 ends in step 3228.

FIG. 9 shows a diagram for explaining a vehicle model for calculating the torques about the vertical axis on the center of gravity of the vehicle. The symbols shown in FIG. 9 have the following meanings:

δ: steering angle at the front axle only EAS α _u: tire slip angle Hinterachsε _v Reifensehräglaufwinkel front ω Fahrzeuggiergeschwindigkεit ß Fahrzεugschwimmwinkεl vFz vehicle speed geradεaus

F tire longitudinal force on axis x (front / rear) and

Side y (right / left) F _Sxy : _lateral tire force on axis x (front / rear) and

Seitε y (right / left)

For the sake of simplicity, it is assumed that the vehicle floating angle and the tire slip angle are small, and thus a splitting of the forces into sine and cosine components without a high loss of accuracy may be avoided. For the moment, it results from the longitudinal force (Indεx L) and lateral force (Index S): M _L = - F _L * SW / 2 for left wheels M _L = F _L * SW / 2 for right wheels M _s = - F _s * lSpV for front axle ^M _s = ^F _s * SpH for rear axle

FIG. 10 shows a flowchart to explain the calculation of moments on the center of gravity of the vehicle about the vertical axis. On the basis of the determined lateral and longitudinal load on the tire, together with the effective lifting arms, the moment on the center of gravity of the vehicle through the respective wheel and the change in this moment can be determined from the changes in forces due to interventions by the ESP and the EAS. This determined values can be summed up for all wheels, which is explained with reference to FIG. 10. First of all, the meaning of the steps shown in FIG. 10 is given:

3501: start

3502: wheel == VL OR wheel == VR ... wheel is on the front axle

3503: M _s = F _s * lSpH ... moment on vehicle center of gravity due to lateral force on rear axle

3504: M _s = - F _s * lSpV ... Momεnt on vehicle center of gravity due to lateral force on the front axle

3505: wheel == VL OR wheel == HL ... wheel is on the left 3506: M _L = F _L * SW / 2 ... moment on vehicle center of gravity due to longitudinal force on the right

3507: M _L = - F _L * SW / 2 ... moment on vehicle center of gravity due to longitudinal force on the left

3508: M _Sp = M _L + M _s ... torque share on the center of gravity of the vehicle through this wheel

3509: end

After the start of the program flow in step 3501, it is determined in step 3502 whether the wheel is on the front axle. If this is the case, then in step 3504 the moment is calculated on the center of gravity of the vehicle by the lateral force on the front axle. If this is not the case, then in step 3503 the moment on the center of gravity of the vehicle is calculated by the lateral force on the rear axle.

It is subsequently determined in step 3505 whether the wheel is on the left side of the vehicle. If this is the case, then in step 3507 the moment on the vehicle's center of gravity is determined by a longitudinal force on the left side. If this is not the case, then in step 3506 the moment on the center of gravity of the vehicle is determined by a longitudinal force on the right side.

In step 3508, the torque component on the center of gravity of the vehicle is then determined by the wheel under consideration

Addition of this in steps 3503 and 3504 and 3506 or 3507 determined moments determined. The program flow ends in step 3509.

FIG. 11 shows a flow chart to explain the calculation of a center of gravity moment by summation. First of all, the meaning of the method steps shown in FIG. 11 is given.

3510: start

3511: M _Gιer = 0, 0. , , Defaults for focus smomment

3512: F _L = F _L Rad _VL F _s = F _g Radv _L. , , Left in the front

3513: Calling up the determination of the moment about the vertical axis on vehicle chp runk

3514: M _Gιer = M _Gler + M _Ξp . , , Yaw moment from summation

Schweptsmomεntε

3515: F _L = F _L wheel,

F _c = FgRady front right

3516: Calling up the determination of the moment about the vertical axis on the vehicle's center of gravity

3517: = M _Gler + M _Sp ... yaw moment from summation center of gravity moment

3518: F _L = F _L wheel _HL F _c = F _s wheel _HL ... rear left

3519: Calling up the determination of the moment about the vertical axis on the vehicle's center of gravity

3520: M _Gιer = M _Gιer + M _Ξp ... yaw moment from summation

Schwεrpunktsmomεnte

3521: F _L = F _L wheel _HR F _s = F _s wheel _HR ... rear right

3522: Calling up the determination of the moment about the vertical axis on the vehicle's center of gravity

3523: M _Gιer = M _Gιer + M _Sp ... yaw moment from summation of center of gravity moments

3524: end

In step 3510, the summation of all wheels for the center of gravity begins. Then, in step 3511, an omission value is set for the center of gravity. In step 3512, the longitudinal force and the lateral force of the wheel are stored on the front left on the variables to be processed.

In step 3513, these are used to determine the moment about the vertical axis to the vehicle's center of gravity. In step 3514, the yaw moment is calculated from the sum of the focus moments. In steps 3515 to 3517, the process explained for the left front wheel using steps 3512 to 3514 is repeated for the front right wheel. Thereafter, the process is repeated in steps 3518 to 3520 for the rear left wheels. Following the calculation for the rear left wheel, the procedure is carried out in the same way for the rear right wheel in steps 3521 to 3523. The process ends in step 3524.

FIG. 12 shows a flow chart to explain the calculation of a center of gravity moment by summation in the case of ESP longitudinal force intervention. Again, the meaning of the procedural steps shown in FIG. 12 is given first.

3401: start

3402: M _G1 E _SP = 0, 0. , , Default assignment for focus - momεnt

3403: F _L = F ^ a ^ -AF ^ Rad ^

F _s = ... Left in the front

3404: Calling up the determination of the moment around the vertical axis on the center of gravity of the vehicle

3405: M _Gl E _SP = M _Gl E _sp + M _Sp ... yaw moment from summation

Focal point smomεnte

F _s = FgRadyp - ΔF _SES pRad _TO . , , front right 3407: Calling up the determination of the moment about the vertical axis on the vehicle's center of gravity

3408: M _Gl E _SP = M _Gl E _SP + M _Sp . , , Yaw moment from summation of center of gravity

F _s = F _Ξ wheel _HL -ΔF _SESP wheel _HL . , , back left

3410: Calling up the determination of the moment about the vertical axis on the vehicle's center of gravity

3411: M _{G: L} E _S p = M _Gτ E _sp + M _Sp . , , Yaw moment from summation focal point omente

3412: F _L = F _L wheel _HR -ΔF _LESP wheel _HR

F _c = , , , back right

3413: Calling up the determination of the moment about the vertical axis on the center of gravity of the vehicle

3414: M _Gl E _SP = M _Gα E _SP + M _Sp . , , Yaw moment from summation

Priority Moments

3415: end

The process begins in step 3401. In step 3402, the skip value for the center of gravity is first set to the value zero. In step 3403, the longitudinal wheel force on the front left wheel and the longitudinal force changes determined for this wheel are subsequently a value is calculated, which is stored on the variable for the longitudinal force. Furthermore, the value for the variable F _{s is} determined from corresponding quantities. In step 3404, the torque about the vertical axis on the center of gravity of the vehicle is determined using the variables determined in step 3403. In step 3405, the yaw moment is calculated by summing the center of gravity moments.

In steps 3406 to 3408, steps 3403 to 3405, which were carried out there for the front left wheel, are carried out for the front right wheel. The steps for the rear left wheel are then carried out in steps 3409 to 3411. Finally, in steps 3412 to 3414, the method for the rear right wheel is carried out. The flow of this program flow ends in step 3415.

FIG. 13 shows a flowchart to explain the calculation of a heavy pulse torque by summation in the event of EAS lateral force intervention.

First, the meaning of the method steps shown in FIG. 13 is given.

3601: start

3602: M _Gl E _AS = 0.0 ... default assignment for the center of gravity

3603: F _L = F _L Rad _VL -ΔF _LBAS RacL _VIι

F _s = , , , Left in the front 3604: Calling up the determination of the moment about the vertical axis on the vehicle's center of gravity

3605: M _Gi E _AS = I ^ E _M + M _Sp yaw moment from summation center of gravity moments

3606: F _L = F ^ ad ^ -AF ^ Rad ^

F _s = F _g R d _vH -ΔFs _E - ^ Radv _R ... front right

3607: Calling up the determination of the moment about the vertical axis on the vehicle's center of gravity

3608: M _Gi E _AE = M ^ + M _Sp yaw moment from summation focal point s omente

3609: F _L = F _L wheel _HL -ΔF _LEAS wheel _H F _s = F _s wheel _HL -ΔF _ΞEAΞ wheel _H rear left

3610: Calling up the determination of the moment about the vertical axis on the vehicle's center of gravity

3611: M ^ s = M _Gi E _AS + M _Sp yaw moment from summation of center of gravity moments

3612: F _L = F _L wheel _HR -ΔF _LEAS wheel _HR F _ς = ^' F _Q wheel “ _p -ΔF _{QC! It;} Wheel _H at the rear right

3613: Calling up the determination of the moment about the vertical axis on the vehicle's center of gravity 3,614: M _Gl E _AS = ^ E ^ + M _Sp . , , Yaw moment from summation focus point smoments

3615: end

After the start of the routine in step 3601, an omission value for the center of gravity of zero is set in step 3602. The longitudinal force used to determine the moment around the vertical axis on the center of gravity of the vehicle is then determined from the longitudinal force and the determined change in longitudinal force. In the same way, the lateral force is determined from corresponding values. In step 3604, the determination of the moment about the vertical axis on the center of gravity of the vehicle is called up using the variables in step 3603. In step 3605, the yaw moment is determined by the summation of the center of gravity moments.

In steps 3606 to 3608, the same method is carried out for the front right wheel as was explained in connection with steps 3603 to 3605 for the front left wheel. In steps 3609 to 3611, the method is then carried out for the rear left wheel. In steps 3612 to 3614, the method for the rear right wheel is carried out. The program flow ends in step 3615.

At this point it is noted that the specified order of the processing of the individual wheels given so far can be changed. FIG. 14 shows a flow chart to explain the formation of intervention moments in ESP and EAS for an intervention evaluation. The change in torque caused by the interventions of ESP and EA.S is understood as a stabilizing moment caused by changes in the longitudinal or lateral force. At this point, other systems that have the same effect but different interfaces can be coupled in. Since such an interface formation can be of great importance in terms of system technology, this step is explicitly carried out as such.

The calculation steps explained in connection with FIG. 14 and the connection steps shown in connection with FIGS. 10 to 13 can serve as an example of the procedure for the formation of the engagement torque in the normal force direction, in order in this way the effect of the interventions in the normal force distribution with respect to the overall vehicle stability to be conclusively evaluated in comparison to systems that influence longitudinal and lateral forces. Analogously to M _s for the lateral force intervention and M _L for the longitudinal force intervention, a signal M _{N is} expected as the interface signal, which describes the change in the yaw moment which is effective on the vehicle's center of gravity around the vertical axis of the vehicle.

First, the meaning of the process steps shown in Figure 14 is given.

3525: start

3526: M _s = M ^ E ^ - M _Gιer . , , Greed omεnt from EAS intervention minus work point 3527: M _L = M _Gl E _sp - M _Gαer . , , Yaw moment from EAS - intervention f minus operating point

352 8: end

After the start of the routine in step 3525, the interface signal for the lateral force intervention is calculated in step 3526 as a difference of the yaw moment from the EAS intervention minus the working point with regard to the lateral force. In a comparable manner, the interface signal for the longitudinal force intervention is calculated by forming the difference in step 3527. This part of the program ends in step 3528.

FIG. 15 shows a flowchart to explain prioritization, evaluation and selection of stabilizing interventions. First, the selection of the maximum torque M _sp Max is explained. The possible interventions on the effect of the center of gravity by means of a nortal force grip, lateral force intervention and longitudinal force intervention f are checked in the following way:

a) Moment through normal force distribution b) Moment through lateral force intervention fc) a) + b) d) g) + a) e) g) + b) f) a) + b) + g) g) Moment through longitudinal force intervention. The number of possibilities is 2 ^{n ~ 1} , where n = 3 = number of possibilities of intervention. These possibilities would be run through in the order mentioned with the aid of a comparison of the amounts and compared with the necessary center of gravity moment M _SP Max previously determined on the basis of a comparison of the amounts. If M _sp Max is reached, then the first intervention in this sequence is selected and permitted. The prioritization of the interventions is thus predetermined in the order of the above listing.

With these simple queries, vehicle stabilization is achieved in any case, if such is requested and can be implemented at all. It is conceivable, for example, that ESP cannot be activated, for example because of a fault in an ABS valve, but nevertheless a necessary stabilizing torque (setpoint slip) is output by the ESP. Its effect is then realized, for example, by EAR through a normal force intervention and EAS through a lateral force intervention.

It is also conceivable, for example, that the torque requirement of ESP is greater than that of EAR and EAS. Therefore the first one is selected as M _SP Max but not put through, since the summation of the moments ^" through normal and lateral force variation is sufficient to represent this moment.

It is also conceivable that a sum intervention - the effect is weaker and thus possibly more comfortable than an individual intervention, for example by the Introducing the rifling forces into falling areas of the characteristic curves. For this reason and in order to check combined intervention at all, the longitudinal force intervention known as uncomfortable is last evaluated via the brake system.

This sequence of arithmetic steps assumes that the longitudinal force intervention means the least comfort and the greatest loss of speed and that a chassis intervention to change the normal force distribution offers the greatest comfort. It is also assumed that an intervention in the steering system to build up lateral force represents a slight loss of comfort for the driver.

The query for amounts is carried out at this point in order to compare interventions in a pre-cleaned manner. The query is sufficient to allow the correct interventions. However, it is a prerequisite that the interventions of the subsystems pursue the same goal; otherwise the overall effect will be noticeably inhomogeneous. For example, it is conceivable that at a point in time a subsystem to improve vehicle stability realizes a reduction in the vehicle swimming angle, for example on the basis of estimation algorithms for the swimming angle. Another subsystem, on the other hand, carries out yaw rate control against understeer tendencies at almost the same time. This could lead to a sequence of interventions that can quickly and noticeably change the way the vehicle is influenced. In the development of such network systems Therefore, special attention must be paid to whether such interventions are noticeable and / or disturbing.

As an alternative to this algorithm, it would be conceivable to weight all interventions in terms of their effect and, after reviewing all interventions, to select the intervention which realizes the required M _SP Max but maintains the smallest possible distance from it. This would make any specification of priorities, as is shown here, superfluous. Instead, a priority would be calculated in each cycle. However, this advantage would be bought with a further increase in calculation.

Before the method shown in FIG. 15 is explained in detail, the significance of the method steps shown in FIG. 15 is given.

Figure 15a:

3801: start

3802: M _SP Max: = 0 ... default assignment for necessary stabilizing torque

M _a) : = M _N ... moment from normal force intervention has 1st priority for stabilization

M _b) : = M _Ξ ... moment from lateral force intervention has 2nd priority for stabilization

M _c) : = M "+ M _s ... moment from normal plus lateral force intervention has 3rd priority M _d) : = M _L + M _N ... moment from longitudinal plus normal force intervention has 4th priority M _g ,: = M _L + M _s ... Moments from longitudinal plus lateral force intervention has 5th priority

M _f) : = M _L + M _Ξ + M _N ... moment from longitudinal + lateral + normal force intervention 6th priority M _g ,: = M _L ... moment from longitudinal force intervention has 7th priority for stabilization

3803: Intervention NO = FALSE ... Intervention on normal force may occur Intervention OFF = FALSE ... Intervention on lateral force may occur

InterventionLAus = FALSE ... Intervention on longitudinal force may take place

3804: | M _L | > | M.pMax | ... stabilizing moment from longitudinal force is greater than necessary stabilizing moment

3805: M _sp Max = M _L ... moment from longitudinal force intervention necessary. stabilizing moment

3806: | M _w | > | M _SP Max | ... stabilizing moment from normal force intervention greater than necessary stabilizing moment

3807: M _S pMax = M _B ... moment from normal force intervention necessary. stabilizing moment

3808: IM _s I> IM _sp Max | ... stabilizing moment from side force intervention greater than necessary stabilizing moment 3809: M _SP Max = M _s ... Momεnt necessary from side force intervention. stabilizing moment

Figure 15b:

3810: | M _a) | <| M _sp Max | ... stabilizing moment from a) smaller in amount than necessary stabilizing moment

3811: EngagementLoff = TRUE ... switch off longitudinal force intervention

InterventionOff = TRUE ... switch off lateral force intervention

3812: | M _b) | <| M _sp Max | ... stabilizing moment from b) smaller in amount than necessary stabilizing moment

3813: EngagementLoff = TRUE ... switch off the longitudinal force intervention

Intervention OFF = TRUE ... switch off normal force intervention

3814: | M _c) | <| M _sp Max | ... stabilizing moment from c) smaller in amount than necessary stabilizing moment

3815: EngagementLoff = TRUE ... switch off the longitudinal force intervention 3816: j M _d) | <| M _SP Max | ... stabilizing moment from d) smaller in amount than the necessary stabilizing moment

3817: Intervention off = TRUE ... switch off normal force intervention

InterventionOff = TRUE ... switch off lateral force intervention

Figure 15c:

3818: | M _e) | <| M _S pMax | ... stabilizing moment from e) smaller in amount than the necessary stabilizing moment

3819: InterventionOff = TRUE ... switch off lateral force intervention

3820: | M _f) | <| M _SP Max | ... stabilizing moment from f) is smaller in amount than the necessary stabilizing moment

3821: Intervention OFF = TRUE ... switch off normal force intervention

3822: end

The program flow begins in step 3801. Subsequently, moments for further processing are calculated in step 3802 depending on the priorities of the interventions. In step 3803 the initial values are determined. to determine whether interventions can take place. It is initially determined that both the normal force intervention, the lateral force intervention and the longitudinal force intervention may take place.

In step 3804 it is determined whether the stabilizing torque from the longitudinal force intervention is greater than the necessary stabilizing torque. If this is the case, the moment from the longitudinal force intervention is stored as a necessary stabilizing moment in step 3805. The process then moves to step 3806. If the query in step 3804 is answered in the negative, the method immediately goes to step 3806.

In step 3806 it is determined whether the stabilizing torque from the normal force intervention is greater than a necessary stabilizing torque. If this is the case, the moment from the normal force intervention is stored in step 3807 as a necessary stabilizing moment. The process then moves to step 3808. If the query in step 3806 is answered in the negative, the method immediately moves to step 3808.

In step 3808 it is checked whether the stabilizing moment from the side force intervention is greater than a necessary stabilizing moment. If this is the case, the moment from the lateral force intervention is saved as a necessary stabilizing moment. The program then goes to step 3810. If this query is answered in step 3808 with Nεin, the process immediately moves to step 3810. In step 3810 it is checked whether the stabilizing moment M _{a) is} smaller in magnitude than the necessary stabilizing moment. If this is the case, both a longitudinal force intervention and a lateral force intervention are deactivated in step 3811.

If the query in step 3810 is answered in the affirmative, then in step 3812 it is determined whether the stabilizing moment M _b , in terms of amount, is less than a necessary stabilizing moment. If this is not the case, a longitudinal force intervention and a normal force intervention are switched off.

If the query in step 3812 is answered with yes, then in step 3814 it is determined whether the amount of the stabilizing moment M _{c) is} smaller than the necessary stabilizing moment. If this is not the case, the longitudinal force intervention is switched off.

If the query in step 3814 is answered in the affirmative, then in step 3816 it is subsequently checked whether the stabilizing torque M _d) is smaller in magnitude than the necessary stabilizing torque. If this is not the case, normal force intervention and lateral force intervention are switched off.

If the question is answered with yes in step 3816, it is determined in step 3818 whether the amount of the stabilizing moment M _{e) is} smaller than a necessary stabilizing moment. If this is not the case, the lateral force intervention is switched off. If the question from step 3818 is answered with yes, step 3820 determines whether the stabilizing moment M _{f) is} smaller in amount than the necessary stabilizing moment. If this is not the case, then the normal force intervention is switched off.

If the question from step 3820 is answered with yes, the method ends in step 3822. The method also ends after the respective deactivation of the intervention variables in steps 3811, 3813, 3815, 3817, 3819 and 3821.

The preceding description of the exemplary embodiments according to the present invention serves only for illustrative purposes and not for the purpose of restricting the invention. Various changes and modifications are possible within the scope of the invention without leaving the scope of the invention and its equivalents.

Claims

Expectations

1. System for monitoring the driving behavior of a vehicle with multiple individual systems (12, 14, 16) for influencing the driving behavior of the vehicle, characterized in that εinε management device (10) for the management of the influencing of driving behavior by the individual systems (12, 14 , 16) is provided.

2. System according to claim 1, characterized in that ESP (12), EAS (14), EAR (16) and / or ABC can be provided as individual systems.

3. System according to claim 1 or 2, characterized in that the management device (10) is implemented in a control unit which communicates with control units of the individual systems via an interface (18, 28, 30).

4. System according to one of the preceding claims, characterized in that the management device (10) is implemented in a separate control device.

5. System according to one of the preceding claims, characterized in that the management device ( ^" 10) is implemented in one or more control unit (s) of the individual systems.

6. System according to any one of the preceding claims, characterized in that

- that the management device (10) is given actual values and setpoint values determined by the individual systems (12, 14, 16),

that the potential effects of the individual systems (12, 14, 16) are determined from the values entered and

that the management device (10) can output values that influence the effects of individual systems (12, 14, 16).

7. System according to one of the preceding claims, characterized in that interventions by individual systems (12, 14, 16) can be suppressed by the management device (10).

8. A method for monitoring the driving behavior of a vehicle, in which the driving behavior of the vehicle is influenced by means of several individual systems (12, 14, 16), characterized in that εinε management device (10) for the management of the influencing of the driving behavior by the individual systems (12 , 14, 16) is provided.

9. Verfahrεn according to claim 8, characterized in that as individual systems ESP (12), EAS (14), EAR (16) and / or ABC can vorεsεhεn εεin.

10. The method as claimed in claim 8 or 9, characterized in that the management device (10) is implemented in a control unit which communicates with control units of the individual systems via an interface (18, 28, 30).

11. The method according to one of claims 8 to 10, characterized in that the management device (10) is implemented in a separate control device.

12. The method according to εinεm dεr claims 8 to 11, characterized in that the management device (10) is implemented in one or more control device (εn) of the individual systems.

13. The method according to one of claims 8 to 12, characterized in that

- that the management device (10) actual values and setpoint values determined by the individual systems (12, 14, 16) are input,

that the potential effects of the individual systems (12, 14, 16) are determined from the given values and

that values can be output by the management device (10), which influence the effects of individual systems (12, 14, 16).

14. Method according to one of claims 8 to 13, characterized in that interventions by individual systems (12, 14, 16) can be suppressed by the management device (10).