DE102013212223A1 - Method for detecting tuning measures - Google Patents

Abstract

A method for recognizing tuning measures by which the actual performance of an internal combustion engine of a motor vehicle is increased compared to a design performance is characterized in that an acceleration (am) in the direction of travel of the vehicle is measured at least once in at least one predetermined operating point of the vehicle a) and b) is compared with a design acceleration (ag) previously measured for this operating point of the vehicle and stored in a memory, and c) when the measured acceleration exceeds the design acceleration by a predeterminable amount, a tuning measure is concluded and the result is saved becomes.

Description

The present invention relates to a method for detecting tuning measures, by which the actual performance of an internal combustion engine of a motor vehicle is increased compared to a design performance. Furthermore, the invention relates to a computer program that performs all the steps of the method according to the invention, when it runs on a computing device, such as a control unit of an internal combustion engine. Moreover, the invention relates to a computer program product with program code which is stored on a machine-readable carrier for carrying out the method when the program is executed on a computer or a control unit.

State of the art

For motor vehicles with gasoline or diesel engine so-called tuning kits or equivalent conversions are offered. The aim of the suppliers is to increase the power and torque of the engine by taking suitable measures. Very different methods are used. For example, sensor data, e.g. the rail pressure in common-rail systems, falsified to achieve higher injection quantities. Other methods change the software or data sets of the engine control units and thereby increase power and torque. These measures are very often marketed under the keyword "chip tuning". So far, such methods are offered only for internal combustion engines. In the future, however, it will also be possible to use these methods also in hybrid or electric vehicles.

These interventions in the engine control not only provide the desired effects, but usually lead to further effects that are problematic or even dangerous. For example, Often the emissions are deteriorated and motor or vehicle components are subject to higher loads. Also, the loss of the operating license and warranty claims is a frequent consequence. In extreme cases, such tuning may even result in damage or destruction of vehicle components. In this case, there is a great interest on the part of vehicle manufacturers to avert unjustified warranty claims. There is therefore a strong interest of the vehicle manufacturers in a reliable detection of manipulations, which should increase the power and / or the torque of the drive.

From the DE 10 2005 039 760 A1 a method for detecting external tuning measures has become known, in which for detecting an external tuning measure, a deviation of an actual power variable from a target power variable, which is provided by the control unit, is evaluated. The actual and the desired power quantity may be, for example, an acceleration of the vehicle. In this method, the target power size and the actual power size are provided and evaluated by the control unit.

A method for detecting tuning measures is also out of the DE 10 2010 049 933 A1 known. This method makes it possible to detect tuning measures by which the actual power of an internal combustion engine of a motor vehicle is increased compared to a design power, wherein deviations of an actual power value from a desired power quantity are provided for detecting the tuning measures provided by a control device become.

Such methods of tuning detection are based on the plausibility of various signals provided in the engine control unit. The accuracy of the method is very limited. In addition, only one particular tuning process is detected. Changes in the data set can be made e.g. not be recognized. Other methods for detecting tuning measures therefore provide redundant sensor information, e.g. the installation of two rail pressure sensors for the detection of the rail pressure signal or the digital transmission of sensor data by means of additional cryptographic protection.

From the IN-201001094 I4 has become known a method that evaluates the acceleration of the vehicle and with the position of the accelerator pedal "plausibility", so checked whether the position of the accelerator pedal can lead to the actual acceleration achieved purely in principle. Also for this purpose, acceleration data provided by the control unit and the position of the accelerator pedal, which can be detected by means of a sensor, are used.

All of these methods only use information at the engine level. This limits the accuracy and selectivity.

Advantages of the invention

The inventive method for detecting tuning measures has the advantage that in at least one predetermined operating point of the vehicle, the acceleration of the vehicle in the direction of travel is measured and compared with a previously for this operating point of the vehicle also measured and stored in a memory design acceleration and then closed on a tuning action and this result is saved when the measured acceleration exceeds the design acceleration by a predeterminable amount. Thus, in contrast to the methods known from the prior art, no variables provided by a control unit are processed here, but actual measured variables characterizing the driving state and in particular the acceleration of the vehicle. In this way, the accuracy is significantly increased and beyond not only a specific tuning method can be detected, but in principle any tuning methods, all of which lead to the result that the internal combustion engine has a higher torque, which leads to a higher vehicle acceleration as a result, which in the end should be achieved with all these tuning methods. The term "design acceleration" is understood to mean the acceleration that can be achieved in certain operating points, in particular the maximum achievable acceleration, of the vehicle on the basis of manufacturer-specific design.

Advantageous embodiments of the method are the subject of the dependent claims on claim 1. Thus, it is advantageously provided that the steps of measuring the acceleration in the direction of travel, comparing this acceleration with a design acceleration stored in a memory and also measured design acceleration and closing on a tuning measure when the measured acceleration exceeds the design acceleration, and storing this result for a plurality is performed by different operating points of the vehicle. In this way, the accuracy of the detection of the tuning measures is increased and in particular any - albeit unlikely - random phenomena that lead to increased acceleration of the vehicle excluded.

It can be preceded according to an advantageous embodiment of the invention, the tuning detection, so the detection of a tuning measure debouncing. In this case, only a two or more times exceeded the difference between measured acceleration and design acceleration by a predetermined size to a corresponding reaction, so to a detection of a tuning measure and possibly other measures, such as storage in a fault memory and / or switching a Fault lamp or the like.

• – Betriebspunkt der Brennkraftmaschine;
• – die Drehrate liegt unter einem vorgebbaren Limit;
• – die Querbeschleunigung und die Beschleunigung um die Hochachse des Fahrzeugs liegen unter einem vorgebbaren Limit;
• – die Neigung des Fahrzeugs um die Querachse liegt unter einem vorgebbaren Limit.

The at least one predetermined operating point of the vehicle is advantageously characterized by one or more of the following conditions:

• - operating point of the internal combustion engine;
• - the rotation rate is below a predefinable limit;
• The lateral acceleration and the acceleration about the vertical axis of the vehicle are below a predefinable limit;
• - The inclination of the vehicle about the transverse axis is below a predetermined limit.

From the rate of rotation can be deduced whether the vehicle is driving substantially straight or is in a rotary motion. Preferably, the operating point is selected so that the vehicle is traveling straight, so the rotation rate is below a predetermined limit. In addition, the lateral accelerations and the acceleration about the vertical axis should be below a predefinable limit, i. no lateral acceleration and no accelerations around the vertical axis exist at the selected operating point. As a result, it can be determined, for example, whether the vehicle is moving on a flat roadway, with a flat roadway here meaning a non-inclined roadway, that is to say a roadway without an incline. In addition, the internal combustion engine should be warm. To capture these specifications, appropriate sensors are installed in the vehicle. Moving on a flat roadway can also be detected, for example, by means of a GPS signal or by means of an inclination sensor, as will be explained in more detail below.

Advantageously, it is provided that, when it is concluded that a tuning measure, an entry is made in a fault memory and / or a MIL lamp is turned on and / or specifiable parameters of the internal combustion engine are limited, in particular the torque, the speed rail pressure. The latter two measures, ie switching on a MIL lamp and / or limiting of predefinable parameters can also be dispensed with, in the event that the vehicle manufacturer does not want to prevent tuning measures but very well recognize and prove.

In order to further improve the boundary conditions for the measurement, it is also possible to use data from the navigation system and / or from the Internet, e.g. accurate position data (GPS), vehicle speed information, vehicle acceleration and outside air temperature.

The acceleration is measured with high precision with the help of sensors, which are installed anyway in today's vehicles, eg sensors whose signals are made available to an ESP system or an anti-lock braking system (ABS). These are acceleration sensors intended to capture the accelerations in all three directions.

The method according to the invention can be executed by a computer program when it runs on a computing device of the control unit. This makes it possible, for example, to implement the method in the control unit of a motor vehicle without having to make structural changes. According to the invention, a computer program product with program code, which is stored on a machine-readable carrier, is also provided for carrying out this method when the program is executed on a computing device of the controller.

Short description of the drawing

An embodiment of the invention is illustrated in the drawing and explained in more detail in the following description.

The figure shows a flow chart of a method according to an embodiment of the invention.

Embodiments of the invention

An embodiment of a method according to the invention is explained below in conjunction with the figure. After a starting block 100 gets in one step 102 set an operating point of the vehicle. This operating point of the vehicle is characterized by a predefinable operating point of the internal combustion engine, that is, for example, speed, rail pressure in the case of a diesel engine, temperature and the like. Further, the operating point is characterized by a rotation rate, which should be below a predetermined limit, by a lateral acceleration and an acceleration about the vertical axis of the vehicle, which should also be below a predetermined limit. The yaw rate can be used to determine whether the vehicle is traveling straight or turning around a bend. Desired is a linear movement, ie a movement in a straight direction. The detection of the lateral acceleration and the acceleration about the vertical axis makes it possible to determine whether the vehicle is moving on a flat roadway. It is desired that the vehicle moves on a flat, ie not inclined roadway. In the context of the present invention, "level" roadway means a non-inclined roadway, that is to say a roadway with an inclination angle = 0 °. The inclination angle of the vehicle can also be determined by a tilt sensor.

With the above-mentioned operating point of the internal combustion engine and the demanded power of the internal combustion engine can be determined, which is variable. This operating point 102 are assigned (maximum) acceleration values a _g , block / step 120 coming from a store (block / step 122 ). These acceleration values are previously measured (in particular maximum) accelerations of the entire vehicle in the longitudinal direction at this operating point 102 of the vehicle. They represent the reference acceleration values achievable with a factory-fitted vehicle. This acceleration is therefore also referred to below as design acceleration. This is to signal that a vehicle designed in this way reaches this (maximum) acceleration.

At the same time, a corresponding longitudinal acceleration a _{m is} measured at this operating point, block 110 , The measurement is done via sensor data from sensors 114 , which are present in today's vehicles anyway for determining the vehicle acceleration in the longitudinal direction and about the vertical axis and in the transverse direction. Namely, this acceleration data is provided in today's vehicle systems that prevent the vehicle from skidding, so-called ESP systems, but also anti-lock braking systems (ABS) and the like. In addition, exact acceleration values are required for airbag systems. These sensors allow a very accurate determination of the acceleration, namely a direct determination of the acceleration. In addition, the acceleration (as well as other relevant variables, such as the inclination of the vehicle,) by other signals 112 be determined, or these signals for verification by means of the sensors 114 determined acceleration values are used. These data are, for example, GPS data of a GPS navigation system, inclination sensors, and the like. The measured acceleration a _m is compared with the stored acceleration a _g by forming the difference Δ, block / step 130 , In a block or step 140 it is checked whether the difference Δ is greater than a predefinable threshold S. If this is the case, the measured acceleration at least by the value S is greater than the stored acceleration a _g . This suggests a tuning measure of the vehicle and therefore an entry into an error memory M, step / block 150 , At the same time, optional in step / block 151 Measures L are initiated, such as a limitation of important engine parameters, such as torque, speed, rail pressure and the like. In addition, a fault message output, ie, switching on a MIL lamp (Malfunction Indicator Light) can also be performed simultaneously, step / block 152 , Optionally, the tuning detection can debounce E (cut / block 141 ) are connected upstream. Then only leads a two- or repeated exceeding (n> 2) of the difference Δ for a corresponding reaction. Debouncing may include measurements at one or more operating points, as shown. This is followed by a return before step / block 160 in which it is checked whether the method described above should be carried out at a new operating point nBP. If this is not the case, in step / block 170 checked whether a repetition W should take place at the same operating point. If not, the process in step stops 180 , If a repetition should occur at the same operating point, before step 102 jump back and the above-described steps are performed again. If, however, in step 160 is determined that the method is to be performed at a new operating point nBP, such a new operating point nBP in step 162 and to the branch point 103 jumped back and a new measurement of the longitudinal acceleration a _m in block 110 at this operating point of the vehicle and this acceleration a _m with a stored, previously measured corresponding acceleration a _g at this operating point in step 130 compared, in which a difference takes place. The acceleration a _g is again the memory 122 taken. Then, the above-described process again runs for this or other new operating points nBP. The entire process can be carried out once or preferably several times at different operating points.

The stored acceleration values a _g are determined for a particular vehicle type in each power variant, which are determined with the series application at specific operating points (eg under full load) and different gear ratios. In this case, maximum values of the vehicle acceleration are determined at specific operating points and in the control unit, ie in the memory 122 stored the controller. In this case, tolerances of the internal combustion engine, the vehicle and corresponding boundary conditions are taken into account. During normal operation of the vehicle, the vehicle longitudinal acceleration is then determined in each case at these previously defined operating points, which occurs, for example, based on the sensor values described above. The acceleration values can in this case be read out by the CAN bus. In this case, it is checked whether the boundary conditions are met and the measured acceleration values are compared with the maximum values also stored in the memory.

The method described above has the great advantage over the methods known from the prior art of relying on measured values. Measured values are used both in relation to the stored values a _g and in the current driving state of the vehicle (a _m ). This makes it possible to determine the acceleration with a considerably higher accuracy than the methods known from the prior art. In addition, the inventive method is not limited to the recognition of a specific specific tuning measure, but can recognize in principle, the most diverse tuning measures regardless of their execution.

The method described above is preferably implemented as a computer program and stored in the control unit. Since the method relies on existing sensor values, it can also be retrofitted on vehicles that have the appropriate sensor. The method enables the precise identification of tuning measures, which can be used, for example, to answer the question as to whether or not the vehicle user has warranty claims.

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 [0004]
• DE 102010049933 A1 [0005]
• IN 201001094 [0007]

Claims (8)

A method for detecting tuning measures, by which the actual performance of an internal combustion engine of a motor vehicle is increased compared to a design performance, characterized in that in at least one predetermined operating point of the vehicle a) at least once an acceleration (a _m ) in the direction of travel of the vehicle is measured and b) is compared with a design acceleration (a _g ) previously measured for this operating point of the vehicle and stored in a memory, and c) if the measured acceleration exceeds the design acceleration by a predeterminable amount (S), then concludes a tuning measure and the result is saved. A method according to claim 1, characterized in that the steps a) -c) are performed in a plurality of different operating points of the vehicle. Method according to claim 1 or 2, characterized in that a tuning measure is only concluded when the steps a) to c) have been carried out at a predefined number of times> 2 for each given operating point of the vehicle and the condition according to step c) was always fulfilled. Method according to one of claims 1 to 3, characterized in that the at least one predetermined operating point of the vehicle is characterized by one or more of the following conditions: - operating point of the internal combustion engine; - the rotation rate is below a predefinable limit; The lateral acceleration and the acceleration about the vertical axis of the vehicle are below a predefinable limit; - The inclination of the vehicle about the transverse axis is below a predetermined limit. Method according to one of the preceding claims, characterized in that when it is closed on a tuning measure, an entry is made in a fault memory and / or a MIL lamp is turned on and / or specifiable parameters of the internal combustion engine are limited, in particular the Torque, the speed, the rail pressure. A method according to claim 1, characterized in that the acceleration in the direction of travel of the vehicle by vehicle-mounted acceleration sensors ( 114 ) and / or via GPS signals ( 112 ) of a navigation system of the vehicle is determined. A computer program executing all the steps of a method according to any one of claims 1 to 6 when executed on a computing device or a control device of an internal combustion engine. Computer program product with program code, which is stored on a machine-readable carrier, for performing a method according to one of claims 1 to 6, when the program is executed on a computing device or a control device.

Images