CN104470783A - Method of detecting an untimely acceleration of a motor vehicle - Google Patents

Abstract

The invention relates to a method of detecting an untimely acceleration of a motor vehicle in which a deviation (e) between a theoretical acceleration and an actual acceleration is determined and an alert cue (w2) is despatched if the deviation (e) is greater than a detection threshold (s), characterized in that the method comprises a phase of resetting at least one parameter, performed when the vehicle is in a situation of operating with no demanded engine torque. The invention also pertains to a vehicle comprising at least one computer configured to implement the method of the invention.

Description

Detect the method for the out of season acceleration of power actuated vehicle

Technical field

The present invention relates to the safety of power actuated vehicle.

More particularly, the present invention relates to the method for the out of season acceleration for detecting power actuated vehicle.

Background technology

If the out of season acceleration of power actuated vehicle occurs suddenly, can form fearful event, it may make the safety of Vehicular occupant be under suspicion.Therefore, it is possible to monitor and identify that the appearance of such event is very important.

When vehicle acceleration, chaufeur does not jam on pedal, or more generally, when vehicle acceleration exceeds the requirement of chaufeur to it, accelerate to be considered to out of season.Determine to accelerate to be whether that out of season known method comprises and is detected acceleration by one of following supervision means:

-when pin lift or more generally at failed call engine torque, the supervision to engine torque: therefore it refer to and confirm not spray in this situation process;

-persistent surveillance to engine torque: therefore it refer to and compared by the moment of torsion of the moment of torsion required and realization;

-persistent surveillance to vehicle acceleration: now, its theoretical acceleration referring to the vehicle estimated by the engine torque required by chaufeur with such as by the car speed differentiate recorded calculate acquisition actual acceleration compare.

But these supervision means have some shortcoming:

Only engine torque is monitored it is inadequate when not needing engine torque: some situation being only limited to vehicle ages.In addition, when not needing engine torque, such as, injection detected when described pin lifts, be not the sign of fault: in the normal operating mode, this situation may occur, such as, for the injection of heatable catalyst.

In addition, for the driving engine of some type, be thorny to the persistent surveillance of engine torque, the such as engine petrol of Stratified Charge (charge stratifi é e), the estimation for moment of torsion is difficult.

All types of vehicle may be applicable to the persistent surveillance of vehicle acceleration.But the efficiency of the method especially depends on the accuracy of the estimated valve to following difference:

-unknown vehicle actual mass and by for referencial use and difference between the quality that adopts,

The actual friction coefficient of-unknown brake facing and with for referencial use and between the friction coefficient that adopts

Difference.

These differences are larger, to the estimated valve more mistake of theoretical acceleration.If this thing happens, if over-evaluate theoretical acceleration, have the risk do not detected, if or underestimate theoretical acceleration, have the risk of false warning.

Summary of the invention

An object of the present invention is the one or more shortcomings solved in these shortcomings.

Present invention also offers a kind of method of the out of season acceleration for detecting power actuated vehicle, wherein, determine the difference between theoretical acceleration and actual acceleration, and if difference is greater than detection threshold, then send warning information, it is characterized in that, the method comprises the stage of calibrating at least one parameter, carries out this stage when vehicle is in the running condition not needing engine torque.In fact, this running condition can carry out failure-free calibration, and therefore improves the accuracy of difference estimation.

Preferably, the stage of calibrating at least one parameter comprises calibrates the quality of vehicle and/or the friction coefficient of vehicle brake sheet.

More preferably, not jamming on the almost nil supplementary calibration condition of brake pedal, the gradient for comprising, performing the calibration to vehicle mass.

More preferably, jamming on brake pedal for comprising, the supplementary calibration condition that the gradient is almost nil, performing the calibration to brake facing friction coefficient.

In a change programme, the time length that the condition of supplementing calibration needs under being included in and not needing the running condition of engine torque, it is included between minimum duration and maximum time length.

Preferably, the time length needed under the running condition of engine torque is not being needed to be included between 300 microseconds and 2 seconds.

Preferably, on the time length needed, the quality of vehicle and/or the aviation value of friction coefficient is asked.

Preferably, when vehicle is under the running condition needing engine torque, the determination to difference is performed.

In a change programme, when vehicle is in the running condition not needing engine torque, monitor nozzle parameter, and send alarm signal when the abnormal injection of hydrocarbon fuel being detected.

The present invention also aims to provide a kind of vehicle, and it comprises at least one computing machine being arranged to and implementing method of the present invention.

Accompanying drawing explanation

After having read the following description of nonrestrictive specific implementation mode of the present invention with reference to accompanying drawing, other characteristic and advantage will manifest, in the accompanying drawings:

-Fig. 1 is the schematic diagram of the logical organization of the method for detecting out of season acceleration of the present invention.

-Fig. 2 is the schematic diagram of the difference calculated between theoretical acceleration/accel and actual acceleration.

-Fig. 3 is the schematic diagram of the calibration value of the friction coefficient calculating vehicle mass or brake facing.

-Fig. 4 is the schematic diagram calculating vehicle mass.

-Fig. 5 is the schematic diagram calculating brake facing friction coefficient.

Detailed description of the invention

Fig. 1 shows the method for detecting out of season acceleration of the present invention in the mode of functional block diagram.The method can be implemented by least one computing machine of power actuated vehicle, and this computing machine receives appropriate information from the sensor included by vehicle or measurer.In the method, when the engine torque that vehicle is in requirement is zero, execution module 1, and when the engine torque required is non-vanishing, execution module 2.Such as decided the execution of appropriate module 1 or 2 by receive logic information t, such as logical message t when the engine torque required is zero, adopted value 1, in other cases, then adopted value 0.

Module 1 and 2 uses the information from multiple source:

-the first group signal a, the sensor that next free A represents and engine controller, such as tachogen,

-the second group signal b, the vehicle sensors that next free B represents and ground connection,

-the first group parameter c, from read-write memory device C.Parameter c comprises the quality of vehicle and the friction coefficient of brake facing,

-the second group parameter d, from read-only memory (ROM) D.

Hereafter with in Fig. 2 to Fig. 5, signal a, b, c, d of different group are distinguished by subscript.

Module 1 comprises the module 10 for monitoring nozzle parameter and the module 11 for calibrating read-write parameter C: the friction coefficient of vehicle mass and brake facing.When module 10 detects the abnormal injection of hydrocarbon fuel, module 1 gives the alarm signal w1.In fact, the abnormal injection of such hydrocarbon fuel may be the reason of the out of season acceleration of vehicle.Such as, the nozzle parameter of data that can monitor such as spray angle, injection duration, engine speed and so on is to confirm the reasonableness of almost nil engine torque.

Module 2 comprises:

-for calculating theoretical acceleration/accel γ _thwith actual acceleration γ _rbetween the module 21 of difference.

Estimation theory acceleration/accel can be carried out by following basic relational expression applied dynamics groundwork (or being abbreviated as PFD):

${\mathrm{\γ}}_{\mathrm{th}}=\frac{{\mathrm{\η}}_{\mathrm{trans}}\·r_{\mathrm{trans}}\·r_{\mathrm{roue}}}{J_{\mathrm{tot}}}\·[C_{\mathrm{mot}}-C_{\mathrm{pertes}\_\mathrm{mot}}]-\frac{r_{\mathrm{roue}}}{J_{\mathrm{tot}}}\·C_{\mathrm{frein}}-\frac{{r_{\mathrm{roue}}}^2}{J_{\mathrm{tot}}}\·[F_{X,\mathrm{roulement}}-F_{\mathrm{aero}}-m_{\mathrm{veh}}\·g\·\sin \left({\mathrm{\θ}}_{\mathrm{pente}}\right)]$

Wherein:

C _motit is the appointment engine torque of requirement.Or rather, the appointment engine torque required corresponds to explains from chaufeur wish the engine torque that the calculating chain of the calibration value (or required value) of the moment of torsion that (interpr é tation Volont é Conducteur) presents produces, described chaufeur wish explain can determine required by chaufeur, in order to consider that engine wear (drives belt, pump ...), outside torque demand (such as, esp, speed regulator, change speed gear box), entertainment requirements and the crank torque that adjusts.

C _{pertes_mot}be engine wear moment of torsion, engine wear comprise such as pump loss, for driving the loss of alternating current generator belt and accessory, (corresponding to the engine torque of specifying and the difference effectively between engine torque)

M _vehvehicle mass,

θ _pentethe gradient,

η _trans=η _pontη _bVbe transmission power, comprise and be respectively η _pontand η _bVthe difference bridge of output and change speed gear box.

R _trans=r _pontr _bVthe ratio r of bridge _pontbe multiplied by change speed gear box ratio r _bVthe transmitting ratio obtained.

R _roueradius of wheel,

F _{x, roulement}, F _aerothe external drag being respectively friction of rolling and air resistance,

C _frein=P _freinμ _freins _freinr _freinby brake pressure P _frein, brake facing area S _frein, brake facing center radius R _freinand the coefficientoffrictionμ of brake facing _freinbe multiplied the braking torque obtained.

J _tot=m _vehr _roue ²+ η _rouer _trans ²j _mottotal inertia of vehicle, wherein J _motthe inertia of driving engine.

As for actual acceleration γ _r, it calculates according at least one observed reading of vehicle power.Such as, can advantageous by the car speed v recorded _vehcarry out differentiate to calculate actual acceleration:

${\mathrm{\γ}}_r=\frac{{\mathrm{dv}}_{\mathrm{veh}}}{\mathrm{dt}}$

Module 2 also comprises:

-for calculating the module 22 of detection threshold s, detection threshold s changes according to the ratio of vehicle gear box,

-for comparing the module 20 of difference e and detection threshold s, when difference e is greater than detection threshold s, send alarm signal w2.

Detection threshold s is theoretical acceleration γ _thwith the actual acceleration γ of vehicle _rbetween permission difference.When hope detects the acceleration/accel difference caused by mistake moment of torsion, in other words, exceed engine torque Δ C, detection threshold s is expressed as the function of the ratio of engaged change speed gear box by following relational expression application power groundwork:

$s=\frac{{\mathrm{\η}}_{\mathrm{trans}}\·r_{\mathrm{trans}}\·r_{\mathrm{roue}}}{J_{\mathrm{tot}}}\·\mathrm{\ΔC}$

Detection threshold s can be selected to detect the engine torque excessively of 25Nm.

As shown in Fig. 2 more accurately, module 21 comprises:

-for estimated engine loss moment of torsion C _{pertes_mot}module 210.Module 210 uses engine speed as input data a2.

-for estimating the module 211 of the moment of torsion being transferred to wheel, adopt following value as input: the engine wear moment of torsion C determined by module 210 _{pertes_mot}, the moment of torsion C of requirement that represented by a1 in Fig. 2 _mot, and supplementary parameter, the change speed gear box ratio r such as, represented by b5 in Fig. 2 _bVor the position b6 of pedal of clutch.

-for estimating friction of rolling F _{x, roulement}module 212, it is according to the vehicle mass m represented by c1 in Fig. 2 _veh.

-for estimated brake moment of torsion C _freinmodule 213, it is according to the coefficientoffrictionμ of the brake facing represented by c2 and b4 respectively in Fig. 2 _freinwith brake pressure P _frein.

-for estimating air resistance F _aeromodule 214, adopt in Fig. 2 the car speed v represented by b1 _vehas input.

-for calculating actual acceleration γ _rmodule 215, adopt in Fig. 2 the car speed v represented by b1 _vehas input.

-for calculating gradient θ _pentemodule 216, its by compare longitudinal acceleration b2 and module 215 place calculate obtain actual acceleration γ _r.

Gradient θ can be estimated by using following relational expression _pente:

g·sin(θ _pente+θ _assiette)＝a _inertielle-ε(v _veh)·γ _r-a _centrifuge

Wherein:

α _inertielle: longitudinal acceleration, is represented by b2 in fig. 2.

θ _assiette: approximate chassis angle, by the actual acceleration γ of vehicle _robtain with proportionality coefficient k:

θ _assiette＝k·γ _r

α _centrifuge: centrifugal acceleration, such as can by the relational expression of following form by travelling angle θ _volantand geometric properties calculates α _centrifuge, the gear reduction ratio coefficient D of geometric properties such as wheelbase E, wheel angle/traveling angle _volant, the sensor station x to represent with x _capteur, (wherein, x=0 refers to and is positioned on trailing wheel):

$a_{\mathrm{centrifuge}}=\frac{{v_{\mathrm{veh}}}^2}{E^2}\·x_{\mathrm{capteur}}\·\sin {\left(\frac{{\mathrm{\θ}}_{\mathrm{volant}}}{D_{\mathrm{volant}}}\right)}^2$

Can also by the rate of bending sensor of track control device (being commonly called ESP) to calculate this centrifugal acceleration.At such as jitter, slip, brake and so on detected in some cases, it is invalid to make the estimation of the gradient.Therefore by gradient θ _pentebe fixed as its last look.

Module 21 also comprises:

-for calculating theoretical acceleration/accel γ _thmodule 217, its by application more detailed power groundwork,

Adopt the result of module 211,212,213,214 and 216, and the vehicle mass m represented by c1 in Fig. 2 _vehas input.

-for comparing the theoretical acceleration γ obtained at module 217 place _thwith the actual acceleration γ calculated at module 215 place _rand determine the difference between these two acceleration/accels calculated and the module 218 exported.

About calibration module 11, as shown in Fig. 3 more accurately, it comprises:

-for confirming for the vehicle mass m represented by c1 in Fig. 3 _vehor the coefficientoffrictionμ of brake facing _freinthe module 110 that the condition of carrying out calibration operation has been collected.Module 110 also adopts such as gradient estimated values theta _pente, the change speed gear box ratio r that represented by b5 in Fig. 3 _bV, pedal of clutch the parameter of position b6, the position b7 of brake pedal, the logical message t of required moment of torsion and so on as input.

-for calculating the module 111 of the duration T of the condition of collecting for carrying out calibration operation.During this duration T, record actual acceleration γ _rchange.

-for calculating vehicle mass m _vehor the coefficientoffrictionμ of brake facing _freinmodule 112.

Module 111 also comprises module 113, and it is for calculating vehicle mass m according to the mean change of the acceleration/accel in whole duration T _vehor the coefficientoffrictionμ of brake facing _freinaviation value in duration T.This can the estimated valve of filtration parameter.Module 113 can also comprise the step confirmed relative to the conformability of the scope of the value of supposition the value calculated during this calibration phase, further, the abnormal estimated valve of such as quality being less than bare weight and so on may have gap with the estimated valve of the reliability of Enhancement Method.In addition, if to coefficientoffrictionμ _freinestimated valve be included in the interval between 0.1 and 0.55, can think that it is actv..Similarly, if to quality m _vehestimated valve be greater than bare weight, can think that it is actv..

About for vehicle mass m _vehcarry out calibration operation and the condition of collecting, the moment of torsion being in requirement when vehicle is the situation of zero, and is performed when being in following supplementary situation:

-do not jam on brake pedal,

-gradient θ _pentealmost nil, preferably, absolute value is less than 1 °.

-the duration T required when the moment of torsion required is zero is greater than minimum threshold t _min, minimum threshold t _mincorrespond to and can keep stable and the minimum duration that the situation that the moment of torsion required is zero is confirmed.Advantageously, minimum threshold t _minbe about 300ms.

-the duration T required when the moment of torsion required is zero is less than max-thresholds t _max.This max-thresholds correspond to fully slow down and simultaneously friction of rolling have the quantity of the point of the interocclusal record of little change to find compromise, it depends on speed.Advantageously, max-thresholds t _maxit is such as 2 seconds.

About for the coefficientoffrictionμ to brake facing _freincarry out calibration operation and the condition of collecting, the moment of torsion being in requirement when vehicle is the situation of zero, and is performed when being in following supplementary situation:

-jam on brake pedal,

-gradient θ _penteit is almost nil,

-require moment of torsion be zero time length be greater than minimum duration t _min, such as 300ms,

-require moment of torsion be zero time length be less than maximum time length t _max, such as 2 seconds.

Because know the accekeration in given duration T, be included in minimum duration t herein _minwith maximum time length t _maxbetween, and according to power groundwork, so can therefrom infer vehicle mass m _veh(under these conditions, engine torque C _mot, braking torque C _frein, gradient θ _pentebe zero), or braking torque C _freinand coefficientoffrictionμ therefore _frein(under these conditions, engine torque C _mot, gradient θ _pentebe zero).Subsequently, in duration T, vehicle mass m can be asked _vehor coefficientoffrictionμ _freinaviation value (module 113).

Fig. 4 and Fig. 5 respectively illustrate by module 112 carry out for determining the vehicle mass m represented by c1 in accompanying drawing _vehand the coefficientoffrictionμ of the brake facing represented by c2 in accompanying drawing _freincalculating.

In the diagram, module 112 comprises:

-for estimated engine loss moment of torsion C _{pertes_mot}module 1120.The drawing of the loss that module 1120 can comprise pump loss and cause due to driving belt attachment and alternating current generator.Module 1120 uses engine speed as input a2.Module 1120 is equal to module 210.

-for estimating the engine wear moment of torsion C driving to wheel _{pertes_mot}module 1121.Module 1121 uses the transmitting ratio/change speed gear box ratio r represented by b5 in Fig. 4 _bVor the position b6 of pedal of clutch (inputting not shown) is as input.Module 1121 is equal to module 211.

-for according to vehicle mass m _vehestimate friction of rolling F _{x, roulement}module 1122.Friction of rolling can be expressed as following form:

F _{X，roulement}＝(a+b.v _veh)·m _veh

Wherein a and b is constant.

-for estimating air resistance F _aeromodule 1124, adopt in Fig. 4 the car speed v represented by b1 _vehas input.Air resistance can be expressed as following form:

$F_{\mathrm{aero}}=\frac{1}{2}\·\mathrm{\ρ}\·S\·C_x\·{v_{\mathrm{veh}}}^2$

Wherein: ρ is density of air, S is the reference surface of vehicle, C _xit is drag coefficient.

-for estimating actual acceleration γ _rmodule 1126, by the car speed v represented by b1 in Fig. 4 _vehcarry out differentiate to obtain actual acceleration γ _r.

-for calculating gradient θ by applying following detailed relational expression _pentethe module 1125 of estimated valve:

g·sin(θ _pente+θ _assiette)＝a _inertielle-ε(v _veh)·γ _r-a _centriluge

-for calculating vehicle mass m _vehthe module 1127 of (being represented by C1 in the diagram), it according to the input of power groundwork and module 1121,1124,1125,1126, therefore is expressed as following form:

m _veh·(r _roue ²·γ _r+(a+b.v _veh)+g.sin(θ _pente))＝

-η _trans·r _trans ².J _mot·γ _r-η _trans·r _trans.·r _roue·C _{pertes_mot}-r _roue ²·F _aero

Wherein, according to vehicle mass m _vehestimate friction of rolling F _{x, roulement}.Friction of rolling can be expressed as following form:

F _{X，roulement}＝(a+b.v _veh)·m _veh

Wherein a and b is constant.

In Figure 5, module 112 adopts the module 1120,1121,1124,1125 shown in Fig. 4 again.As shown in Fig. 5 again, module 112 also comprises:

-for calculating braking torque C _freinmodule 1127 ', it is according to the input of power groundwork and module 1121,1122,1124,1125,1126.

-for calculating coefficientoffrictionμ _freinthe module of (being represented by c2 in Figure 5).Module 1123 adopts the braking torque C determined at module 1127 ' place _freinand brake pressure P _frein(inputting not shown) is as input.

The invention has the advantages that and can come by utilizing the situation of any moment of torsion of wherein failed call (such as because chaufeur does not jam on acceleration pedal):

The acceleration of-persistent surveillance vehicle,

The uncertainty of-minimizing parameter, and the risk therefore reducing error detection and do not detect.

-guarantee the safe operation demand of the fearful event for out of season acceleration.

The invention provides the diatropism of more simply calibration and the method to estimated valve, in other words, the method can easily be applicable to all vehicles.

Claims (10)

1. for a method of inspection for the out of season acceleration of power actuated vehicle, wherein, determine theoretical acceleration (γ _th) and actual acceleration (γ _r) between difference (e), and if described difference (e) is greater than detection threshold (s), then send warning information (w2), it is characterized in that, described method comprises the stage of calibrating at least one parameter, performs described calibration when described vehicle is in and does not need the running condition of engine torque.

2. method of inspection according to claim 1, is characterized in that, the described stage of calibrating at least one parameter comprises the quality (m to described vehicle _veh) and/or the friction coefficient (μ of brake facing of described vehicle _frein) calibrate.

3. method according to claim 2, is characterized in that, does not jam on brake pedal, the gradient (θ for comprising _pente) almost nil supplementary calibration condition, perform the quality (m to described vehicle _veh) calibration.

4. according to claim 2 or method according to claim 3, it is characterized in that, jamming on brake pedal, the gradient (θ for comprising _pente) almost nil supplementary calibration condition, perform the friction coefficient (μ to described brake facing _frein) calibration.

5. according to claim 3 or method according to claim 4, it is characterized in that, the time length (T) that described supplementary calibration condition needs under being included in and not needing the running condition of engine torque, it is included in minimum duration (t _min) and maximum time length (t _max) between.

6. method according to claim 5, is characterized in that, under the running condition not needing engine torque, the time length (T) of described needs is included between 300 milliseconds and 2 seconds.

7. according to claim 5 or method according to claim 6, it is characterized in that, on the time length (T) of described needs, ask described vehicle mass (m _veh) and/or described friction coefficient (μ _frein) aviation value.

8. the method according to any one in aforementioned claim, is characterized in that, when described vehicle is under the running condition needing engine torque, performs the determination to described difference (e).

9. the method according to any one in aforementioned claim, it is characterized in that, when described vehicle is in the running condition not needing engine torque, monitor (10) nozzle parameter, and send alarm signal (w1) when the abnormal injection of hydrocarbon fuel being detected.

10. a vehicle, comprises at least one computing machine, and described computing machine is arranged to the method implemented according to any one in aforementioned claim.