CLIAMS:We claim:
1. A device (16) to control an operation of an engine of a vehicle (10), said device (16) adapted to receive vehicle speed from a vehicle speed sensor(12) of the vehicle (10) and a gear position from a gear position sensor(14) of the vehicle (10);
said device (16) characterized in that,
an electronic control unit (26) adapted to select a gear curve corresponding to said gear position received from said gear position sensor (14) and determine a reference speed for said gear position, said electronic control unit (26) adapted to calculate a deviation speed from said received vehicle speed and said reference speed; said device (16) adapted to determine value of a parameter corresponding to said deviation speed from said selected gear curve and control operation of said engine based on said parameter value.
2. The device (16) claimed in claim (1), wherein said electronic control unit (26) comprises a clutch state sensor (13) adapted to determine a state of a clutch.
3. The device (16) claimed in claim (1), wherein said gear curve represents a relation between a plurality of said parameter and a plurality of said deviation speeds.
4. The device (10) claimed in claim (1), wherein said electronic control unit (26) comprises an activating means (22) adapted to provide a signal to said device (16) to transmit said value of a parameter.
5. The device (10) claimed in claim (1), wherein said electronic control unit (26) comprises a reference means (20) adapted to set said reference speed.
6. The device (10) claimed in claim (1), wherein said electronic control unit (26) limits said vehicle speed by controlling an injection quantity to be injected into an injector (28).
7. A method to operate a device (10) claimed in claim (1),said method comprising:
-receiving a vehicle speed;
- receiving a gear position;
said method characterized in:
- selecting a gear curve corresponding to said gear position;
-calculating a deviation speed from said received vehicle speed and a reference speed;
-determining a value of parameter corresponding to said deviation speed from said selected gear curve;
- controlling said operation of said engine based on said parameter value.
,TagSPECI:Field of the invention
[001] This invention relates to a device to control an operation of an engine of a vehicle.
Background of the invention
[002] Simulating the vehicle on a test stand is substantial a quicker and a more efficient way of examining the behavior of the motor vehicle than vehicle testings on the road. Since only very few variables can be measured on the test stand directly, like the engine speed and the engine torque, it is necessary to calculate the other, non-measurable variables by a simulation model. With a simulation model which is calibrated on the basis of a real vehicle, it is possible to obtain reliable statements which are close to reality on the behavior of the real vehicle under various conditions. The result of the tests on the test stand shall be designated as evaluation variable. Depending on the specific problem to be solved on the test stand, a large number of evaluation variables can be determined. Such evaluation variables are for example the fuel consumption in certain situations or in certain driving cycles, certain types of exhaust gas emissions or the amplitude of bucking oscillations by performing certain driving maneuvers. To achieve a realistic simulation of driving conditions, a synchronizing effort is necessary .According to the current state-of-the-art the synchronizing effort has as its goal to repeat the test run over and over and to synchronize the parameters of the driver model. According to current art, the parameters are then basically frozen and maintained during the time of the actual test.
[003] Many techniques are known in the state of art method of operating of a device to control an operation of an engine of a vehicle
[004] An US granted patent 7668706 discloses a method for simulating the driving behavior of vehicles on a test stand. A simulation model calculates simulation values of variables which are representative of the driving state of the vehicle, in that the reaction of the vehicle to the behavior of the engine and the values of the variables are calculated.

Brief description of the accompanying drawings
[005] An exemplifying embodiment of the invention is disclosed in detail in the description and illustrated in the accompanying drawings:
[006] Figure 1 illustrates a block diagram of a device according to one embodiment of the invention; and
[007] Figure 2 illustrates a flowchart of a method of working of a device according to one embodiment of the invention.
[008] Detailed description of the invention:
[009] Figure 1 illustrates a block diagram of a device to control an operation of an engine of a vehicle according to one embodiment of the invention. The device 16 adapted to receive vehicle speed from a vehicle speed sensor 12 of the vehicle 10 and a gear position from a gear position sensor14 of the vehicle10.An electronic control unit 26 adapted to select a gear curve corresponding to said gear position received from the gear position sensor 14 and determine a reference speed for the gear position, the electronic control unit 26 adapted to calculate a deviation speed from the received vehicle speed and the reference speed. The device 16 adapted to determine value of a parameter corresponding to the deviation speed from the selected gear curve and control operation of the engine based on the parameter value.
[0010] The electronic control unit 26 comprises an activating means 22 adapted to provide a signal to the device 16 to transmit the value of the parameter. For instance, the parameter can be a voltage value. The gear curve is a curve representing a plurality of values of the parameter Vs a plurality of deviation speeds. The electronic control unit 26 comprises a memory 24 adapted to store a plurality of gear curves associated with a plurality of gear numbers during a calibration process. For instance, if the gear number is 2, the gear curve associated with that gear number will be different from the gear curve associated with the gear number 3. Initially, during the calibration process, the gear curves are generated by varying an accelerator pedal. The variation in the deviation speed with respect to the variation in the accelerator pedal is stored in the form of a gear curve. The deviation speed increases with the increase in the variation of the accelerator pedal. The variation of the accelerator pedal is mapped to a variation in a value of the parameter from a minimum value to a maximum value in respective gear number. For instance, if the parameter is a voltage value, in gear number 2, the variation of the accelerator pedal from 0%-100% will be mapped to variation of the voltage from 0V-5V.If the variation in the accelerator pedal is 20%, the voltage will be 1V. If the variation in the accelerator pedal is 40% and the voltage will be 2V. The electronic control unit 26 also comprises a clutch state sensor 13 adapted to determine a state of a clutch. The electronic control unit 26 maintains a constant vehicle speed during the change of the gear. The electronic control unit 26 takes the clutch state sensor 13 as an input during the change of the gear. For instance, the vehicle 10 is running at a speed of 40 kmph in the gear number 2, the user changes the gear to gear number 3, the electronic control unit 26 maintains the speed of the vehicle 10 at 40 Kmph during the change of the gear number from 2 to gear number 3. The accelerator pedal will not be in a working condition during the performance testing process, instead, the device 16 provides the variation of the accelerator pedal in the form of various values of the parameter. The user of the vehicle 10 during the performing testing process will be only shifting the gear as required.
[0011] The vehicle speed sensor 12 measures the speed of the vehicle 10. Simultaneously, the gear position sensor 14 determines the gear number of the gear. The vehicle speed and the gear number are given as inputs to the electronic control unit 26. The calculating means 18 present in the electronic control unit 26 calculates the deviation speed from the vehicle speed and the reference speed. The reference speed will be set by a reference means 20. The electronic control unit 26 selects the gear curve associated with the gear number stored in the memory. The activating means 22 provides a value of a parameter to the device 16 to transmit a value of the parameter. The value of the parameter to be transmitted is obtained from the gear curve corresponding to the current gear. The value of the parameter associated with the deviation speed is transmitted by the device 16 to the electronic control unit 26 to limit the speed of the vehicle 10. For instance, if the parameter is a voltage value, the deviation speed is 20kmph and the voltage associated with the deviation speed is 2V.The activating means 22 checks the allowable voltage to be transmitted and provides a signal to the device 16 to transmit 2V of voltage signal. The device 16 after receiving the signal from the activating means 22 transmits a voltage signal of 2V to the electronic control unit 26. The electronic control unit 26 limits the speed of the vehicle 10 in dependence with the parameter value transmitted from the device 16. The electronic control unit 26 limits the speed of the vehicle 10 by controlling the injection of a fuel quantity into an injector 28.
[0012] For example, the vehicle 10 is in gear 2 and a maximum threshold speed is 60Kmph.If the actual speed of the vehicle 10 is 50Kmph, the electronic control unit calculates the deviation speed from the actual vehicle speed and the reference speed. The deviation speed is +10Kmph. From the gear curve, if the voltage associated with 10Kmph is 1V.The electronic control unit 26 provides a signal to the device 16 to transmit a 1V of voltage to the electronic control unit 26.The electronic control unit 26 increases the speed by increasing the injection quantity into the injector of the engine.
[0013] And also in other scenario, if the actual speed of the vehicle 10 is 70Kmph, the electronic control unit calculates the deviation speed from the actual speed of the vehicle 10 and the reference speed. The deviation speed is -10Kmph. The electronic control unit 26 reduces the speed of the vehicle 10 by reducing the injection quantity into the injector of the engine.
[0014] Figure 2 illustrates a flowchart of a method of working of a device to control an operation of an engine of a vehicle according to one embodiment of the invention. In step S1 (a), a speed of a vehicle 10 is received. In step S2 (a), a deviation speed from the vehicle speed and a reference speed is calculated. In step S1 (b), a gear position of a gear is determined. In step S2 (b), a gear curve corresponding to the gear position is selected. In step S3, a value of parameter corresponding to the deviation speed from the selected gear curve is determined. In step S4, the operation of the engine based on the parameter value is controlled.
[0015] In another embodiment of the invention, the device 16 can be integrated in the electronic control unit 26 to limit the speed of the vehicle 10.
[0016] With the device 16 and the method operating the device 16 disclosed above, a better repeatability of results can be obtained during the performance testing process. The method disclosed can be used in both manual transmission mode and in automatic transmission mode.

[0017] It must be understood that the examples and embodiments of the components explained in the detailed description are only illustrative and do not limit the scope of the invention. The scope of this invention is only limited by the scope of the claims.