DE102011108697A1 - Method for detecting manipulation of engine control unit of motor vehicle, involves comparing calculated reference value for the acceleration of vehicle with actual measured acceleration, to detect manipulation of engine control unit - Google Patents

Abstract

A reference value for the acceleration of motor vehicle is calculated, based on performance data of vehicle, and the operational data of motor vehicle, which is stored in motor vehicle, is detected by the sensors in motor vehicle. The actual acceleration of motor vehicle is detected through the sensor. The actual acceleration of reference value differs for the acceleration of motor vehicle, if manipulation of engine control unit is present. The calculated reference value is compared with the actual measured acceleration to detect manipulation of engine control unit. An independent claim is included for a system for detecting manipulation of engine control unit of motor vehicle.

Description

The invention relates to a method for detecting the manipulation of an engine control unit of a motor vehicle according to the preamble of claim 1 and to a system, in particular for carrying out the method according to the preamble of claim 10.

By manipulating the sensor data collected in a motor vehicle, it is possible to increase the performance of the motor vehicle (so-called tuning), which at the same time leads to increased safety risks in road traffic, possibly resulting in overuse of components and therefore by the manufacturer of the vehicle, also with regard to clear contingent liabilities, is undesirable. There is therefore a need for protection against such manipulation.

In the prior art, methods are known in which such interventions are recognized. The DE 10 2005 039 760 A1 shows, for example, a method for detecting external tuning measures, in which the deviation of an actual power quantity from a target power size, which is provided by the control unit, is evaluated.

This method has the disadvantage that it makes no indication as to how the controller is coming to the desired power size it provides.

On this basis, the object of the present invention is to provide a method and a system which do not have this disadvantage.

This is accomplished by a method having the features of claim 1 and a system having the features of claim 10.

• – Berechnen eines Referenzwertes für die Beschleunigung des Kraftfahrzeugs, anhand von Entwicklungsdaten des Kraftfahrzeugs, Betriebsdaten des Kraftfahrzeugs, die in dem Kraftfahrzeug gespeichert sind und/oder durch Sensoren im und/oder am Kraftfahrzeug erfasst werden,
• – Erfassen der tatsächlichen Beschleunigung des Kraftfahrzeugs mittels einer Sensorik (vorteilhaft im Fahrzeug), wobei die tatsächliche Beschleunigung von dem Referenzwert für die Beschleunigung des Kraftfahrzeugs abweicht, wenn eine Manipulation des Motorsteuergeräts vorliegt,
• – Vergleichen des berechneten Referenzwertes mit der gemessenen tatsächlichen Beschleunigung zum Feststellen einer Manipulation des Motorsteuergeräts.

Thereafter, a method for detecting the manipulation of an engine control unit of a motor vehicle, comprising the following steps:

• Calculating a reference value for the acceleration of the motor vehicle, based on development data of the motor vehicle, operating data of the motor vehicle, which are stored in the motor vehicle and / or detected by sensors in and / or on the motor vehicle,
• Detecting the actual acceleration of the motor vehicle by means of a sensor system (advantageously in the vehicle), the actual acceleration deviating from the reference value for the acceleration of the motor vehicle when there is a manipulation of the engine control device,
• - Comparing the calculated reference value with the measured actual acceleration for detecting a manipulation of the engine control unit.

This is based on the idea that the acceleration behavior is recorded statistically in the control electronics and compared with reference values that would reach the production vehicle. From the extent of exceeding the limit value for the acceleration by amount, time and frequency over the driving cycles, it can then be determined by means of a weighted evaluation matrix that the vehicle may have been manipulated to increase its performance.

g:

Erdbeschleunigung

c_w:

Luftwiderstandsbeiwert

A:

Stirnfläche des Fahrzeugs

v:

Fahrzeuggeschwindigkeit und

r:

Luftdichte.

The reference value for the acceleration of the motor vehicle a _ref preferably indicates which vehicle acceleration would have to occur in the case of an unmanipulated motor vehicle. Furthermore, the operating data are advantageously the known quantities on the one hand:

G:

acceleration of gravity

c _w :

Drag coefficient

A:

Face of the vehicle

v:

Vehicle speed and

r:

Air density.

While the gravitational acceleration is known for all vehicle types (9.81 m / s ² ), the coefficient of air resistance and the frontal area of the vehicle can preferably be taken from the vehicle data sheet and stored. The vehicle speed can advantageously be calculated from the wheel speed. The air density under standard conditions (kg / m ³ ) depends on the air pressure and the temperature. For T = 20 ° C and p = 1013 hPa, the air density is for example 1.204 kg / m ³ . The value of the atmospheric air pressure is preferably present in the engine control. In order to keep the error in the calculation of the air resistance as small as possible, preferably also the exact air density can be calculated in each case from the atmospheric air pressure, the gas constant (287,058) and the current temperature in Kelvin.

m_ist:

tatsächliche Fahrzeugmasse,

f:

Rollreibungskoeffizient,

a:

Steigungswinkel/Neigungswinkel und

e:

Drehmassenzuschlagsfaktor

In addition, the operating data are advantageously the inaccurate quantities:

m _is :

actual vehicle mass,

f:

Rolling friction coefficient,

a:

Pitch angle / tilt angle and

e:

Rotating mass loading factor

The actual vehicle mass m _ist = m ₁ can be advantageously during the thrust phase of the motor vehicle in the plane (inclination angle = 0 °) can be determined using the vehicle deceleration.

ist ersichtlich, dass eine geringere gemessene Fahrzeugverzögerung a₁ gegenüber der gerechneten Sollverzögerung a₀ einer höheren Fahrzeugmasse als dem Bezugsmassenwert m₀ zugerechnet werden kann; ist die gemessene Verzögerung a₁ aber größer als a₀, dann ist die tatsächliche Fahrzeugmasse m₁ gegenüber dem Bezugsmassenwert m₀ geringer, die Fahrwiderstandskraft bremst das leichtere Fahrzeug schneller ab. Weiterhin können vorzugsweise Massezunahmen durch Beladung wie auch Masseabnahmen durch Entladungen berücksichtigt werden. Vorteilhaft beträgt der Rollreibungskoeffizient für Luftreifen mit Soll-Luftdruck für Beton, Asphalt 0,013 -. Aus dem Rauschanteil im Signal der Radgeschwindigkeit bildet sich bevorzugt genau der Zustand der Fahrbahnoberfläche ab: Je weniger verrauscht das Geschwindigkeitssignal ist, desto besser ist der Fahrbahnbelag, weshalb dann der zugrunde gelegte Rollreibungswiderstand zutreffend ist. Bevorzugt lässt sich der Steigungswinkel/Neigungswinkel mit Hilfe des ESP-Gierratensensors (ein kombinierter Sensor für Quer- und Längsbeschleunigung mit Neigungswinkelangabe) bestimmen, es sind aber auch eigenständige Neigungssensoren mit höherer Genauigkeit denkbar. Stationär ist die Neigungsinformation dabei vorzugsweise im Bereich von 1° genau. Zukünftig kann vorteilhaft mit dem Satelliten-Navigationssystem Galileo/GPS II mit einer Auflösung von 10 cm mit präziseren Angaben zur Streckenkontur gerechnet werden. Der Drehmassenzuschlagsfaktor, ist bevorzugt aus dem Fahrleistungsdatenblatt entnehmbar und abhängig vom eingelegten Gang und der Raddrehzahl.From the formula

It can be seen that a lower measured vehicle deceleration a ₁ with respect to the calculated target deceleration a ₀ a higher vehicle mass and the reference mass value m ₀ can be allocated; if the measured deceleration a ₁ is greater than a ₀ , then the actual vehicle mass m _{1 is} lower than the reference mass value m ₀ , the driving resistance force brakes the lighter vehicle more quickly. Furthermore, it is preferably possible to take into account mass increases due to loading as well as mass decreases due to discharges. Advantageously, the rolling friction coefficient for pneumatic tires with target air pressure for concrete, asphalt 0.013 -. From the noise component in the signal of the wheel speed, the state of the road surface is preferably formed precisely: the less noiseless the speed signal is, the better the road surface, which is why the underlying rolling friction resistance is then correct. Preferably, the pitch angle / inclination angle can be determined with the aid of the ESP yaw rate sensor (a combined sensor for transverse and longitudinal acceleration with an inclination angle specification), but independent inclination sensors with higher accuracy are also conceivable. Stationarily, the inclination information is preferably in the range of 1 °. In the future, the Galileo / GPS II satellite navigation system with a resolution of 10 cm can be used to calculate the route contour with more precise information. The Drehasszuschuschungsfaktor, is preferably removed from the Fahrleistungsdatenblatt and depending on the gear engaged and the wheel speed.

In order to keep the proportion of the air resistance force to the total driving resistance force small, preferably the calculation of the driving resistance force is limited to a speed range below the maximum speed.

The sensor information is preferably obtained by so-called polling (cyclic polling). Equivalent, however, is the use of interrupt requests or a recursive structure.

• – Bewertung einer beim Vergleich der gemessenen tatsächlichen Beschleunigung von dem berechneten Referenzwert festgestellten Abweichung mithilfe einer Bewertungsmatrix,
• – Setzen eines Merkers, der einen Häufigkeitszähler inkrementiert, wenn auf Grund der Bewertung mithilfe der Bewertungsmatrix eine Manipulation von Sensordaten des Kraftfahrzeugs erkannt wird.

In a further advantageous embodiment, the following further steps are provided:

• Evaluation of a deviation determined from the comparison of the measured actual acceleration from the calculated reference value by means of an evaluation matrix,
• - Setting a flag that increments a frequency counter, if based on the evaluation using the evaluation matrix, a manipulation of sensor data of the motor vehicle is detected.

The flag is preferably a so-called flag, ie a binary variable or a status indicator that can be used to identify certain states. The flag can in particular be set or deleted and read out.

In order to calculate the reference value for the acceleration of the motor vehicle, in particular, a drive force provided by the vehicle, a driving resistance force counteracting the acceleration, a rotational load supplement factor and the mass of the motor vehicle are preferably used.

Further preferably, the driving resistance force is calculated in particular by means of the rolling resistance force of the motor vehicle, the pitch resistance, the air resistance and the acceleration resistance.

The rolling resistance force F _Rollw. is preferably calculated according to the formula: F _roll. = f × G = f × m × g, where f is the rolling friction coefficient of the tires, G is the weight of the vehicle, m is the mass of the vehicle and g is the acceleration due to gravity.

The rolling friction coefficient is an empirical quantity and depends on the condition of the road surface. It is for car tires with standard air pressure:
Concrete / asphalt: 0.013
Cobblestone: 0.015

From the formula it can be seen that with the same vehicle weight, the rolling resistance changes only insignificantly with changing road surface.

Further preferably, the gradient _resistance F _{Steigw calculated.} according to the formula: F _Steigw. = m × g × sin (α), where m again denotes the mass of the vehicle, g again the gravitational acceleration and sin (α) the inclination angle of the vehicle. In the Plane is the slope _resistance F _Steigw. = 0, since sin (α) = 0 for α = 0 °.

For a gradient, the same amounts result, but with a negative sign, since sin (α) becomes negative for angles <0 °. Then, the gradient resistance force changes to the downhill force, which reduces the running resistance force F _w by that amount, and therefore the required driving force F _A is reduced by the same amount - the engine must perform less.

The air resistance F _Luftw. according to the formula: F _Luftw. = 1/2 × ρ × c × _W × A × (v + _vw ) ² , where ρ is the air density (1.202 kg / m ³ [200 m above sea level]), c _w the drag coefficient, A the face of the vehicle, v the vehicle speed and v the wind speed.

Preferably, the acceleration _resistance force F is _Dezw. according to the formula: F _dec. = e × m × a is calculated, where e denotes the rotational lash surcharge factor> 1, in the mass of the motor vehicle and a the acceleration of the motor vehicle. To linearly accelerate a body requires a force that is proportional to mass and acceleration.

Since in a motor vehicle in the drive train in particular rotating parts (crankshaft, gearbox, drive shafts, wheels) are, which are afflicted with an inertia, they act as an additional mass that must be accelerated - because only from the acceleration of the rotating masses then follows the Longitudinal acceleration of the vehicle mass. This inertia of the rotating masses thus acts as an additional vehicle mass, which counteracts the acceleration. For this reason, it is preferable to simplify the calculation by forming a factor - the rotational load adding factor e - which correspondingly reflects the inertia of the rotating masses, which are gear-dependent. The factor is therefore> 1 and is preferably used for general considerations with + 10% of the vehicle mass, ie e = 1.1. For more precise calculations, the rotational mass supplement factors for the gears 1, 2, ... x with e ₁ , e ₂ , ... e _x are used, which are taken from the vehicle data sheet.

In a further advantageous embodiment, the driving force provided by the motor vehicle is calculated from the torque of the engine, the total ratio of the drive train, the radius of the wheel and the overall efficiency of the drive train. In this case, the driving force F _{A is} preferably according to the formula: F _A = M × i / r × η where M is the engine torque, i is the total driveline ratio, r is the radius of the wheel, and η is the overall powertrain efficiency. The engine torque is preferably present as an actual torque in the engine control. The overall ratio of the drive train, the radius of the wheel and the overall efficiency of the drive train are in turn advantageously known from the vehicle data sheet.

The comparison of the calculated reference value with the measured actual acceleration preferably takes place by means of a subtraction. In particular, the evaluation matrix preferably comprises the weighting factors frequency of an acceleration overshoot, height of the acceleration difference amount and acceleration overshoot time.

The task of the evaluation matrix is, in particular, to ensure, on the one hand, that a standard-fit vehicle is not erroneously recognized as a tuned vehicle. On the other hand, a tuned vehicle should also be recognized as such. It follows that a single acceleration overshoot within the tolerances advantageously not sufficient to assume a tuning suspicion. For this a statistical evaluation is necessary. This takes into account the frequency (= 1 Weighting factor) from exceeding the actual acceleration a _is the vehicle on the reference acceleration a _ref + _.DELTA.S a threshold value = limit value. Accelerations above the reference value but below the limit are preferably not taken into account. Acceleration values of a _is > a _ref + a _ΔS are preferably weighted. The greater the acceleration exceeded ("acceleration difference amount" = 2nd weighting factor), the more it is weighted. The longer the acceleration difference a _is - (a _ref + a _ΔS )> 0 is present ("acceleration overshoot time" = 3rd weighting factor), the more it is weighted.

From the three weighting factors, a cumulative weighting factor is preferably formed, to which a maximum value is assigned. In particular, each of the three weighting factors can be the same or contribute a different share to the cumulative weighting factor.

The weighting factors "frequency", "acceleration difference amount" and "acceleration overshoot time" are advantageously stored at the end of each drive cycle and are thus available as start values in the next drive cycle. This ensures that weighting factors are not lost if the cumulative weighting factor has not yet reached its maximum value because the journey has ended prematurely. If the maximum value of the cumulative weighting factor is reached or exceeded, a flag is set (meaning: "Tuning detected"), which increments a frequency counter by 1. Subsequently, all weighting factors are preferably reset and the process starts again.

The flag and the frequency counter are preferably in a protected area of the storage means and are secured against unauthorized overwriting. The storage means is preferably a permanent (eg ROM, PROM) or semi-permanent memory (eg EPROM, flash EEPROM), since it also saves the stored data without a permanent power supply. However, the use of any other suitable memory is possible, as long as it ensures the permanent storage of the data. The flag and the frequency counter are advantageously part of a comprehensive data collection of hex values that are not differentiated from each other and whose positions are not identifiable (thus there is no way to delete exactly this flag and frequency counter).

The evaluation matrix may preferably be extended by motor variables (measured values or learned values) which are suitable for detecting increases in power or torque indirectly or in combination with others (eg actual rail pressure, mass flow of exhaust gas recirculation, actual boost pressure, lambda Signal, exhaust gas temperature before turbocharger) to broaden the physical basis for securing the tuning detection.

Finally, a system for detecting the manipulation of an engine control unit of a motor vehicle, with a calculation means which is set up and provided, based on operating data of the motor vehicle, which are stored in the motor vehicle and / or detected by sensors in and / or on the motor vehicle, to calculate a reference value for the acceleration of the motor vehicle, a detection means which is arranged and provided to detect by means of a sensor, the actual acceleration of the motor vehicle, the actual acceleration of the reference value for the acceleration of the motor vehicle deviates, if a manipulation of the engine control unit is present, a comparison means, which is arranged and provided for detecting a manipulation of the engine control unit to compare the calculated reference value with the measured actual acceleration, a judging means adapted thereto and is provided to evaluate a deviation detected in the comparison of the measured actual acceleration and the calculated reference value by means of a scoring matrix and a memory device arranged and arranged to set a flag which increments a frequency counter when, on the basis of the scoring, using the Evaluation matrix is detected a manipulation of sensor data of the motor vehicle.

Preferably, the calculation means is a microprocessor. But it is also possible any other device that can process the data and perform the appropriate calculation. Advantageously, the comparison means is a differential filter. The memory device is advantageously a permanent (eg ROM, PROM) or semi-permanent memory (eg EPROM, flash EEPROM), since it also saves the stored data without a permanent power supply. However, the use of any other suitable memory is possible, as long as it ensures the permanent storage of the data.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102005039760 A1 [0003]

Claims (10)

Method for detecting the manipulation of an engine control unit of a motor vehicle, comprising the following steps: Calculating a reference value for the acceleration of the motor vehicle, based on development data of the motor vehicle, operating data of the motor vehicle, which are stored in the motor vehicle and / or detected by sensors in and / or on the motor vehicle, Detecting the actual acceleration of the motor vehicle by means of a sensor system, the actual acceleration deviating from the reference value for the acceleration of the motor vehicle when there is a manipulation of the engine control unit, - Comparing the calculated reference value with the measured actual acceleration for detecting a manipulation of the engine control unit. Method according to claim 1, characterized by the further steps: Evaluation of a deviation determined from the comparison of the measured actual acceleration from the calculated reference value by means of an evaluation matrix, - Setting a flag that increments a frequency counter, if based on the evaluation using the evaluation matrix, a manipulation of sensor data of the motor vehicle is detected. Method according to one of claims 1 to 2, characterized in that for calculating the reference value for the acceleration of the motor vehicle in particular provided by the vehicle driving force, a driving acceleration force counteracting the acceleration, a Drehmassenzuschlagsfaktor and the mass of the motor vehicle are used. A method according to claim 3, characterized in that the driving resistance force is calculated in particular by means of the rolling resistance force of the motor vehicle, the pitch resistance, the air resistance and the acceleration resistance. A method according to claim 3, characterized in that the driving force provided by the motor vehicle from the torque of the engine, the total ratio of the drive train, the radius of the wheel and the overall efficiency of the drive train is calculated. Method according to one of claims 1 to 5, characterized in that the comparison of the calculated reference value with the measured actual acceleration takes place by means of a subtraction. Method according to one of claims 1 to 6, characterized in that the evaluation matrix, in particular the weighting factors - frequency of overshooting, - amount of the acceleration difference amount and - acceleration timeout includes. A method according to claim 7, characterized in that the weighting factors are stored at the end of each driving cycle. Method according to one of claims 1 to 8, characterized in that the flag and the frequency counter are stored in a tamper-protected storage means. System for detecting the manipulation of an engine control unit of a motor vehicle, in particular for carrying out the method according to one of claims 1 to 9 with: - A calculation means, which is set up and provided, based on development data of the motor vehicle, operating data of the motor vehicle, which are stored in the motor vehicle and / or detected by sensors in and / or on the motor vehicle, to calculate a reference value for the acceleration of the motor vehicle . A detection means, which is set up and intended to detect the actual acceleration of the motor vehicle by means of a sensor system, the actual acceleration deviating from the reference value for the acceleration of the motor vehicle, if there is a manipulation of the engine control unit, A comparison means arranged and provided for detecting a manipulation of the engine control unit to compare the calculated reference value with the measured actual acceleration, A rating means arranged and designed to evaluate a deviation found in the comparison of the measured actual acceleration and the calculated reference value by means of an evaluation matrix, A memory device, which is set up and provided to set a flag which increments a frequency counter if a manipulation of sensor data of the motor vehicle is recognized on the basis of the evaluation with the aid of the evaluation matrix.