RU2627952C2 - Method for control terminal working from the motor vehicle clutch position readout system - Google Patents

Abstract

FIELD: transportation.

SUBSTANCE: in the method for the control terminal working from the clutch position readout system, the clutch pedal position is controlled, the transition area is defined, determined by the of clutch pedal positions range, in which the control terminal is one of two alternative clutch pedal positions, containing the released clutch pedal position and pedal depressed position. The sliding threshold displacement is also set from the clutch pedal initial position, which if intersected when the clutch pedal position is within the transition area, causes the change of the clutch pedal position and the control terminal from the current position to the alternative position, if the sliding threshold is crossed.

EFFECT: starting and stopping characteristics of the motor are improved.

22 cl, 7 dwg

Description

FIELD OF TECHNOLOGY

This invention relates to a motor vehicle having an internal combustion engine and, in particular, to a motor vehicle having a system for automatically starting and stopping the internal combustion engine based at least in part on the clutch engagement state.

BACKGROUND

It is known that a motor vehicle having a manual transmission should be equipped with a start-stop system for automatically stopping and starting the internal combustion engine used to provide the power consumed by the movement for the motor vehicle.

The start-stop system automatically stops the engine whenever it is determined that it is possible to do so in order to reduce fuel consumption and reduce emissions from the engine.

For manual transmission start-stop applications, the threshold 'clutch pedal depressed / clutch pedal released' is normally used to indicate the driver's intention to leave when the clutch is depressed, so that a start-stop system can initiate engine start. The same threshold can also be used to indicate when the driver has released the clutch pedal and intends to remain stationary long enough for the start-stop system to shut off the engine to save fuel.

The released condition of the clutch pedal is often used as a condition for the start-stop system to carry out likelihood checks related to the start-stop system. Credibility tests are established that must be successfully completed once in each key cycle before starting start-stop. One example of such a likelihood test is to check whether the signal of the transmission sensor is consistent with the estimate of the current driven gear based on the ratio of engine speed to vehicle speed for a known gear ratio. This test, if successfully passed, will indicate that the transmission sensor is functioning properly.

In order to successfully perform such a comparative test, while the test is running, there should be no slippage between the clutch discs, that is, the clutch should be engaged. The condition for indicating that the drive to the drive wheels is fully engaged is to check whether the clutch pedal is released beyond the clamping point (clutch). Therefore, as long as the threshold 'clutch pedal depressed / clutch pedal released' is set to occur in a more released pedal position than the clamp point, the released clutch pedal state can be used as a condition for performing the test.

The problem with using a fixed threshold is that the clutch pedal is depressed / the clutch pedal is released, that there is a compromise between starting / stopping as opposed to the determining attribute of driving capabilities based on a calibrated threshold. In order to give as much time as possible to start the engine when the driver presses the clutch pedal, it is desirable to set the threshold value as high as possible along the pedal, for example, depressed by 10%. That is, the position where the driver does not have to depress the clutch pedal very far from the fully released position in order to initiate engine starting. This arrangement improves the perceived performance of the engine start or the energy of the start. One of the problems when setting the threshold near the top of the pedal stroke is that many drivers (a real-life test shows somewhere around 35 to 40%) keep their foot on the clutch pedal, which is sometimes called holding the clutch, or while riding in a gear with a fully engaged clutch, and / or when the vehicle is stationary with a transmission in neutral with an engaged clutch, which means that the threshold value would always be exceeded.

FIG. Figure 2 shows the three states of adhesion, Released, Depressed, and Depressed, and thresholds for transition between states. These three states are typically used today in start-stop applications with a neutral stop.

In zone “R”, the clutch pedal is released, that is, the clutch will be uniquely engaged, in zone “D” the clutch pedal will be depressed, and the clutch will unblock unambiguously, and in zone “P” the clutch pedal will be depressed and the clutch could be engaged or disengaged depending on the location of the clutch pedal in the “P” zone.

The most significant threshold is that which lies between the pressed and released state, indicated by Th _RP in FIG. 2.

Next, we consider four possible scenarios: in the first scenario, Th _{RP is} set to 10% of the clutch pedal stroke, and the driver completely removes his foot from the clutch pedal, in the second scenario, Th _{RP is} set to 30% of the clutch pedal stroke, and the driver completely removes his foot from the clutch pedal, in the third scenario, Th _{RP is} set to 10% of the clutch pedal stroke, and the driver holds the clutch pedal so that it remains pressed 25% of the clutch pedal stroke, in the fourth scenario, Th _{RP is} set to 30% of the clutch pedal stroke and driver holding ie the clutch pedal, so that it remains down 25% from the clutch pedal.

In the first scenario, the launch will be quick, and time is available to test the likelihood;

In the second scenario, the launch will not be responsive, as the clutch pedal must be depressed 30% to achieve it. However, there is a lot of time for believability testing;

In the third scenario, the engine will not stop, since the threshold of Th _{RP will} usually not be crossed, and a likelihood check, therefore, may not occur; and

In the fourth scenario, the launch will be fast, and there is time for likelihood testing.

Therefore, there are problems with scenarios two and three for the reason that they can cause one or more of the poorly perceived start-stop performance, the reduced availability of the start-stop operation, and can mislead the driver if plausibility testing is not possible deactivation of the start-stop system.

An object of the present invention is to provide an improved method and apparatus for controlling the start-stop operation of an engine mounted on a motor vehicle having a manual transmission that minimizes or eliminates the problems mentioned above.

SUMMARY OF THE INVENTION

According to a first aspect of the invention, there is provided a method for generating a control terminal from a clutch position reading system, the method comprising monitoring a clutch pedal position of a motor vehicle, determining a transition zone defined by a range of clutch pedal positions in which the control terminal is one of two alternative position states clutch pedals containing the released state of the clutch pedal and the depressed state of the clutch pedal, setting the sliding threshold offset from the initial position of the clutch pedal, which, if crossed when the position of the clutch pedal is within the transition zone, will cause a change in the state of the clutch pedal position, and a change in the control output from the current state to an alternative state if the sliding threshold is crossed.

The method may further comprise setting the maximum displacement of the sliding threshold from the position of the clutch pedal.

If the state of the clutch pedal is the released state in the initial position of the clutch pedal, then the value of the sliding threshold may have a value greater than the value of the initial position of the clutch pedal.

If the state of the clutch pedal is the depressed state in the initial position of the clutch pedal, then the value of the sliding threshold may have a value less than the value of the initial position of the clutch pedal.

If the position of the clutch pedal is within the transition zone, the method may further comprise determining the state of the clutch pedal position as released if the final clutch pedal position is less than the sliding threshold.

If the position of the clutch pedal is within the transition zone, the method may further comprise determining the state of the clutch pedal position as depressed, if the final position of the clutch pedal is greater than or equal to a sliding threshold.

When the position of the clutch pedal and the sliding threshold are both within the transition zone, the method may further comprise moving the sliding threshold so as to maintain a predetermined offset from the position of the clutch pedal if the position of the clutch pedal moves from the initial position of the clutch pedal from the sliding threshold.

If the position of the clutch pedal moves from the initial position of the clutch pedal to the sliding threshold, the value of the sliding threshold may remain the same until the position of the clutch pedal has moved a predetermined distance beyond the sliding threshold.

The transition zone may be limited at the lower end to the lower limit of the clutch pedal position, and at the upper end to the upper limit of the clutch pedal position.

The released zone can be determined by the range of the clutch pedal positions, limited at one end to the fully released clutch pedal position, and at the other end to the lower limit of the clutch pedal position, and the control terminal can always indicate the released state of the clutch pedal position whenever the pedal position the clutch is within the released zone and the pressed zone can be determined by the range of clutch pedal positions, limited at one end to the upper limit of the clutch pedal position tions and limited, at the opposite end, a fixed upper threshold, and the control output can always point to the pressed state of the clutch pedal position whenever the position of the clutch pedal is pressed within the zone.

The depressed zone can be determined by the range of the clutch pedal positions, limited at one end, by a fixed upper threshold, and by the fully depressed clutch pedal position at the opposite end, and the control terminal can always indicate the depressed state of the clutch pedal position whenever the clutch pedal position is within the squeezed zone.

The displacement of the sliding threshold from the initial position of the clutch pedal can determine the transition window limited at one end by the position of the sliding threshold, and at the opposite end by the initial position of the clutch, and the transition window can always be located on the side of the initial clutch position towards the clutch position zone alternative state of clutch position.

The method may further comprise adjusting the sliding threshold by a very small amount each time a sliding threshold is calculated to allow for inadvertent changes in the position of the clutch pedal.

The correction of the sliding threshold may comprise increasing the offset from the initial position of the clutch pedal to the sliding threshold by a very small amount each time a sliding threshold is calculated.

If the value of the sliding threshold is greater than the initial position of the clutch, the displacement can be increased by adding a very small value to the current value of the sliding threshold.

Alternatively, if the value of the sliding threshold is less than the initial engagement position, the displacement can be increased by subtracting a very small value from the current value of the sliding threshold.

A very small value may be less than 1% of the offset value.

The method may further comprise supplying a control terminal from the clutch position reading system to the start-stop system of the motor vehicle for use in controlling the stop and start of the engine of the motor vehicle.

According to a second aspect of the invention, there is provided a clutch position reading system for sensing a position of a clutch pedal of a motor vehicle and providing a control output indicating a positional state of a clutch pedal, the system comprises position sensing means for providing a signal indicating a current position of the clutch pedal and an electronic clutch pedal position processor for processing the signal from the position sensing means, while if the position of the clutch pedal is in within the transition zone limited by the fixed lower limit of the position of the clutch pedal and the upper fixed limit of the position of the clutch pedal, in which the state of the clutch pedal position is one of the released and pressed, the electronic clutch pedal position processor is configured to set the sliding threshold offset from the initial position of the clutch pedal, which, if intersected when the position of the clutch pedal is within the transition zone, will cause a change in state n Proposition clutch pedal and change management with output indicating the current state of the clutch pedal position to provide an alternate condition of the clutch pedal, if crossed by a sliding door.

If the clutch pedal is in the released state in the initial position of the clutch pedal, the electronic clutch pedal position processor may be configured to set a sliding threshold value so that it has a value greater than the value of the initial clutch pedal position, and if the clutch pedal is in pressed in the initial position of the clutch pedal, the electronic clutch pedal position processor can be configured to set a sliding threshold value s, so that it has a value smaller than the value of the initial position of the clutch pedal.

The electronic clutch pedal position processor may be configured to set a maximum offset of the sliding threshold from the position of the clutch pedal.

The electronic clutch pedal position processor may further be configured to correct the sliding threshold value by a very small amount each time a sliding threshold is calculated to allow for inadvertent changes in the position of the clutch pedal.

The correction of the sliding threshold may comprise increasing the offset from the initial position of the clutch pedal to the sliding threshold by a very small amount each time a sliding threshold is calculated.

If the value of the sliding threshold is greater than the initial position of the clutch, the displacement can be increased by adding a very small value to the current value of the sliding threshold.

If the value of the sliding threshold is less than the initial engagement position, the displacement can be increased by subtracting a very small value from the current value of the sliding threshold.

A very small value may be less than 1% of the offset value.

The electronic clutch pedal position processor may be configured to provide a control output from the clutch position readout system to a start-stop system of a motor vehicle for use in controlling a stall and engine start of a motor vehicle.

According to a third aspect of the invention, there is provided a motor vehicle having an engine, clutch, the engagement state of which is controlled by the clutch pedal, a system for automatically starting and stopping the engine based on at least changes in the position of the clutch pedal, and a clutch position reading system for sensing the position of the clutch pedal, constructed in accordance with said second aspect of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Further, the invention, by way of example, will be described with reference to the accompanying drawings, in which:

FIG. 1A is a schematic representation of a motor vehicle having a start-stop system according to the invention;

FIG. 1B is a schematic representation of a clutch drive system forming part of the start-stop system of FIG. one;

FIG. 2 is a schematic representation of an operating range of a clutch pedal showing three predetermined zones in accordance with the prior art;

FIG. 3 is a schematic diagram showing an operating range of movement of a clutch pedal showing four predetermined zones in accordance with the invention;

FIG. 4 is a flowchart showing a first embodiment of a method for generating a control output from a clutch position reading system according to the invention;

FIG. 5 is a flowchart showing a second embodiment of a method for generating a control output from a clutch position reading system according to the invention;

FIG. 6 is a schematic diagram showing six changes in the engagement position and the resulting state transitions.

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIG. 1A and 1B, a motor vehicle 5 is shown having an engine 10 driving a multi-speed transmission 11. The transmission 11 is operably connected to the engine 10 by a clutch 8 (not shown in FIG. 1A), which is engaged or released manually by the driver of the motor vehicle 5 and has a gear selector (not shown). The gear selection means is movable between several positions, including at least one position where a gear forming part of the multi-speed transmission is selected and a neutral position in which no multi-speed transmission is selected. When the gear selector is shifted to the neutral position, the multi-speed transmission 11 is referred to as being in a neutral state in which the drive cannot be transmitted by the multispeed transmission, and when the gear selector is shifted to the gear position, the multi-speed transmission 11 is referred to as being in a gear in which the drive can be transmitted by multi-speed transmission.

The engine starter in the form of an integrated starter-generator 13 with the possibility of drive is connected to the engine 10 and, in this case, is connected by a flexible drive in the form of a drive belt or chain drive 14 to the crankshaft of the engine 10. The starter-generator 13 is connected to an electric energy source in the form battery 15 and is used to start the engine 10, and which is charged by the starter-generator when it functions as an electric generator. The invention is not limited to using a starter-generator 13, and the starter-generator 13 could be replaced by a starter motor to start the engine 10.

It should be noted that, during the start of the engine 10, the starter-generator 13 drives the crankshaft of the engine 10, and that at other times, the starter-generator is driven by the engine 10 to generate electrical energy.

A driver-controlled on / off device in the form of a key-controlled ignition lock 17 is used to control the overall operation of the engine 10. That is, when the engine 10 is running, the ignition 17 is in the 'on ignition key' position, and when the ignition 17 is in the ' the ignition key is off, engine 10 is not able to work. The ignition lock 17 also includes a third short-term position used to manually start the engine 10. It will be appreciated that other devices can be used to provide this functionality, and that the invention is not limited to using the ignition lock.

The electronic control unit 16 is connected to the starter-generator 13, to the engine 10, to the sensor 12 of the gear selection tool used to monitor whether the transmission 11 is in neutral or in gear, to the running speed sensor 21 used to measure the speed of the running wheel 20 , to the brake pedal position sensor 24 used to monitor the position of the brake pedal 23, to the clutch pedal position reading system used to monitor the position of the clutch pedal 25, and to the throttle position sensor 19, used to control the position of the accelerator pedal 18. The accelerator pedal 18 provides a driver input of the required power output from the engine 10. If the accelerator pedal 18 has been moved from its original position, it is said to be in the depressed position or in the depressed state.

Although the measurement of the speed of a motor vehicle is described above with reference to the use of the wheel sensor 21, since such sensors are often already present on the motor vehicle as part of an anti-lock braking system, it should be appreciated that other suitable means can be used to determine the speed of the motor vehicle means 5, for example, such as a sensor measuring the frequency of rotation of the output shaft from the transmission 11.

It should be noted that the term gear selector sensor is not limited to a sensor that monitors the position of the gear selector, but rather is any device that can provide feedback on whether the transmission 11 is in gear or in neutral.

Similarly, the term brake pedal sensor is not limited to a sensor that monitors the position of the brake pedal, but rather is any device that provides feedback on whether the driver of the motor vehicle 5 applied pressure to the brake pedal 23 to apply the brakes of the vehicle 5. For example The brake pedal sensor could monitor the fluid pressure in one or more brake lines. When the brake pedal 23 has been pressed sufficiently to apply the brakes, it is referred to as being depressed or depressed.

In this case, the clutch pedal position reading system includes a linear position sensor 26 used to monitor the actual position of the clutch pedal 25 and an electronic clutch pedal position processor 16C (EC3P) used to process the position signal from the clutch position sensor 26 to a control terminal for use the electronic control unit 16 using logic stored in the EC3P 16C.

The clutch position sensor 26 may comprise one or more position sensors, such as rotary potentiometers.

The state of the clutch pedal 25 as pressed or released is determined by the EC3P 16C forming part of the electronic control unit 16 using the clutch position signal received from the position sensor 26. The clutch position signal represents the current position (CP) of the clutch pedal 25.

As shown in FIG. 1B, the clutch drive system, in this case, is formed by the clutch pedal 25, the main hydraulic cylinder 27, the auxiliary hydraulic cylinder 28 and the clutch release lever 29, which engages and releases the clutch 8 through the release bearing 9. However, attention that other means could be used to convert the movement of the clutch pedal 25 into engagement or disengagement of the clutch 8, and that the invention is not limited to the use of a hydraulic clutch drive system I am.

It should also be appreciated that the clutch pedal position electronic processor 16C (EC3P) might be a separate unit, and might not be formed as part of the main start-stop control electronic unit 16.

The electronic control unit 16 receives several signals from the engine 10, including a signal indicating the number of revolutions of the engine 10 from a speed sensor (not shown) and sends signals to the engine used to control the silencing and starting of the engine 10. In this case, engine 10 is a spark ignition engine 10, and signals sent from the electronic control unit 16 are used to control a fuel supply system (not shown) for engine 10 and an ignition system (not shown) for engine 10. If Atel 10 was supposed to be a diesel engine, it would only manage the supply of fuel to the engine. The electronic control unit 16 contains various components, including a central processing unit, memory devices, timers, and signal processing devices for converting signals from sensors connected to the electronic control unit 16 into data that is used by the electronic control unit 16 to control operation and , in particular, automatic stop and start of the engine 10.

During normal engine operation, the electronic control unit 16 is configured to control the fuel supplied to the engine 10 and to adjust the ignition system so that sparks are supplied to the engine 10 from the spark plugs with the correct timing to create the desired engine torque.

The electronic control unit 16 controls the operation of the engine 10, which can operate in two modes, the first or the mode of operation with automatic start-stop, and the second or continuous operation. However, it should be borne in mind that one or more separate electronic controllers could be used to control the normal operation of the engine 10, and the electronic controller 16 could only control the switching of the engine 10 between the two operating modes and the automatic stop and start of the engine 10.

The electronic control unit 16 is further configured to determine whether it is appropriate to operate the engine 10 in the first mode by checking one or more operating parameters of the engine before allowing operation in the first mode.

These engine operating parameters include engine coolant temperature, whether any catalytic converters associated with the engine are ignited, and whether the engine rotates within a predetermined range of revolutions. For example, if the coolant temperature is less than, say, 65 ° C, or the catalytic converter is not ignited, or the engine speed is greater than, say, 1110 revolutions per minute (RPM), then entry into the first mode is prohibited, and the electronic control unit 16 is configured to drive the engine 10 in a warm-up mode, in which the engine 10 is continuously operated regardless of whether the motor vehicle 5 is moving or stationary.

Once it is determined that the operating conditions of the engine have been satisfied, then the start-stop system is set to the first operating mode when one or more predetermined conditions for stopping and starting the engine exist.

These engine stop and start conditions are for the neutral stop system based on the signals received by the electronic control unit 16 from the gear selector sensor 12 and EC3P 16C. If the control terminal from EC3P 16C indicates that the clutch pedal 25 is not depressed, and the signal from the gear selector sensor 12 indicates that a neutral has been selected, then the engine 10 is stopped, and when the control terminal from EC3P 16C indicates that the clutch pedal 25 is pressed, the engine 10 restarts immediately, or when the gear selector sensor indicates that the neutral is no longer selected.

It should be noted that an additional operating condition that is used by many systems is whether the motor vehicle 5 is moving. In this case, operation in the first mode is prohibited if the speed of the motor vehicle 5 is above a predetermined low speed.

Next, with reference to FIG. 3 schematically shows how the EC3P 16C processes the output from the clutch pedal position sensor 26 over the operating zones based on the percentage of the fully depressed position.

In zone "R", the control terminal from EC3P 16C will indicate that the clutch pedal 25 is released, that is, the clutch 8 is engaged.

In zone "D", the control output from the EC3P 16C will indicate that the clutch pedal 25 is depressed and the clutch 8 is disengaged.

In zone "P", where the clutch clamping point 8 is located, the control terminal from EC3P 16C will indicate that the clutch pedal 25 is depressed.

In the “P or R” transition zone, the control output from the EC3P 16C will depend on the location and movement of the clutch pedal 25.

The released zone “R” is defined by a lower limit of 0% and an upper predetermined fixed limit Ll, which, in this case, has a value of 10%.

The squeezed zone “D” is defined by the upper limit of 100% and a predetermined fixed threshold Th2, which, in this case, has a value of 70%.

The transition zone “P or R” is defined by the lower predetermined fixed limit Ll and the upper predetermined fixed limit Lu, which, in this case, has a value of 30%. The upper predetermined fixed limit Lu is selected so that it has a positioning value less than the expected clutch holding point 8, but greater than the positioning value due to the shift of the clutch pedal 25 due to the holding of the clutch pedal 25.

The pressed zone “P” is defined by the lower predetermined fixed limit Lu and the predetermined fixed threshold Th2.

An additional sliding tracking threshold Th1 operates within the transition zone 'P or R' and is limited by the lower limit Ll and the upper limit Lu. That is, Lu≥Th1≥Ll.

The general operation of the EC3P 16C will now be explained with reference to six exemplary state transitions numbered “A” through “F” in FIG. 3.

Transition “A” between states indicates the transition of the clutch pedal (CP) position from the Depressed to the Released direction. Crossing the upper limit of the Lu transition zone in this direction will cause the state of the control output from the EC3P 16C to change from pressed to released.

The transition "C" between the states in which the position of the clutch pedal moves from the transition zone to the pressed zone will always lead to the conclusion of pressing. Whether a state change occurs when the upper fixed limit Lu is crossed will depend on whether the initial state is released or depressed.

The transition "E" between the states in which the position of the clutch pedal CP moves the lower limit Ll from the released zone to the transition zone causes a transition in the control terminal from EC3P 16C from released to pressed.

The transition “F” between states indicates the transition from the transition zone through the lower fixed limit Ll in the Discharged direction. Crossing the lower limit of the transition zone Ll in this direction will always cause a transition in the control terminal from the EC3P 16C from pressed to released if the initial state was pressed, or saves the state as released if the initial state was released.

The transition "B" between the states indicates the displacement of the clutch pedal within the transition zone towards the depressed position (increase in the release), accompanied by a decrease in the release of the clutch pedal, such as the transition "A" of the clutch. That is, the clutch was released to the X0 position of the clutch pedal, where X0 represents the most released clutch pedal position within the transition zone, and now moves in the opposite direction, so that the clutch pedal is depressed. X1 is the final idle position of the clutch pedal, and 'x' is the shift of the clutch pedal.

The transition window (not shown in Fig. 3) lies on the pressed side of the position X0 of the clutch pedal, the width of the transition window, in this case, is a predetermined small value 'w', which is the offset between the initial position X0 and the tracking threshold Th1. The location of the transition window is on the pressed side of X0 because the tracking threshold Th1 accompanies or follows the position of the clutch pedal 25 through the offset 'w', and movement so that the arrival in X0 is from Pressed towards Release. In the example shown, X1 is shown shifted from X0 by a distance 'x' equal to 'w', therefore, it lies on the threshold Th1, and the adhesion state remains released, since the tracking threshold Th1 has not been crossed. If the tracking threshold Th1 were crossed, that is, x '>' w ', the state would be changed to the pressed state, since the tracking threshold Th1 was crossed.

Continued movement of the clutch pedal position in the same direction as discussed above will not move the tracking threshold Th1 until the clutch pedal position has moved in the clutch release direction more than the width 'w' of the transition window beyond the current position of the tracking threshold Th1. Note that the transition window will then be reassigned so as to lie on the released side of the clutch pedal position as soon as the driven threshold Th1 is passed.

Since no transition window is present on the released side of the X0 position of the clutch pedal, no state changes will occur if the clutch pedal position continues to move from the X0 position. The tracking threshold Th1 will follow it behind at a distance of 'w' in order to maintain a small transition window on the pressed side of the clutch pedal position.

The transition “D” between states indicates the displacement of the clutch pedal within the transit zone towards the released position (reduction of release), which follows the movement towards the released state, such as “d”.

In this case, the transition window will lie on the released side of the Z0 position of the clutch pedal, since it has moved from the more released position towards the less released position, and in this case, the previous monitoring threshold has been crossed, causing the state to be pressed. If the clutch pedal moves from Z0 to Z1 in the direction of releasing the clutch pedal to a distance of 'z', then no state changes will occur, since, in this case, 'z' = 'w', where 'w' is the width of the transition window bounded at the released end by the tracking threshold Th1. However, if 'z' increases by more than 'w', that is, the position of the clutch pedal crosses the tracking threshold Th1, then the state will change from pressed to released, and the transition window will lie on the pressed side of the clutch pedal position.

Continued movement of the clutch pedal position in the same direction as discussed above will not move the tracking threshold Th1 until the clutch pedal position has moved in the direction of releasing the clutch more than the width 'w' of the transition window beyond the current position of the tracking threshold Th1.

Since no transition window is present on the pressed side of the clutch pedal position Z0, no state changes will occur if the clutch pedal position moves from the Z0 position in the pressed direction. The tracking threshold Th1 will follow it behind at a distance of 'w' so as to maintain a small transition window from the released side of the clutch pedal position until the tracking threshold is equal to the upper fixed limit Lu. Note that the upper limit value Lu will not have an effect in this case, since the state is already pressed.

Therefore, a tracking sliding threshold Th1 is set, which follows the actual position of the clutch pedal 25 (CP in FIGS. 4 and 5), while the driver depresses and releases the clutch pedal 25, and this tracking threshold Th1 is used along with the position the clutch pedal remains within the transition zone to make state changes when a small change in the position of the clutch pedal occurs in a direction opposite to the previous direction of the clutch pedal.

By setting the tracking threshold bias Th1 to be a small number, such as, for example, 5% of the total stroke of the clutch pedal position, relatively small changes in the clutch pedal position can be used to make state changes of the clutch pedal position.

The tracking threshold Th1 follows the position of the clutch pedal at a constant distance, called the transient offset 'w', when the position of the clutch pedal is moving from the driven threshold Th1. The driven threshold Th1 will then begin to track the position of the clutch pedal when the position of the clutch pedal has moved more than an offset 'w' beyond the previous driven threshold Th1. The sliding threshold Th1 is always limited to remain between the lower limit Ll and the upper limit Lu.

In relation to the driver of a motor vehicle 5 that holds the clutch pedal 25, moving the clutch pedal 25 towards the pressed position, which is commonly used to initiate engine start-up by the start-stop system, is the compatible pedal departure distance (w%) regardless of the actual value depressing the clutch pedal due to holding the clutch pedal 25 within the normal expected limits, such as from 15 to 25%.

Therefore, improvements in the start-stop system can be made by setting the offset of the trailing threshold Th1 to a small value, such as w% of the clutch pedal position from the control value of the clutch pedal position, which, if crossed, causes a state change.

A value of w%, for example, could be chosen as 5%, which is a value large enough to avoid false transitions triggered by signal noise or inadvertent movements of the driver’s foot caused by vibration or twitching, but small enough to give a sense of vigor engine driver.

Note that in order to avoid fast repeating transitions across borders, hysteresis is provided to prevent multiple switching between states. That is, two driven thresholds are provided, and not one, as discussed above.

An additional improvement is to adaptively recognize X0 and Z0. This makes it possible for the driver’s foot to move slowly (crawl) in any direction along with the attempt to continue to hold the pedal. Inadvertent changes in the position of the clutch pedal are often referred to as slow progression of the clutch pedal. Using the learning element with a time criterion, X0 and Z0, it is possible to slowly adapt to help avoid unnecessary transitions between states. Thus, the start-stop system can distinguish between a tired foot and the clear intentions of the driver. The driver’s clear intention to continue to press or release the pedal indicating a desire to start driving, shift gear or engage the clutch completely would be defined as when a movement greater than w% was detected within a short predetermined period of time.

With reference to FIG. 6, six changes in the position of the clutch pedal are shown in more detail, and how the slave threshold Th1 is assembled so as to define one end of the transition window having an opposite end located in the clutch pedal position used to set the slave threshold Th1. Moving the position of the clutch pedal within the transition window will not cause a change in the state of the position of the clutch pedal, and will not move the position of the sliding driven threshold Th1.

It should be noted that all defined states are supplied as output from the EC3P 16C to the electronic control unit 16 for use in controlling the start-stop system of the motor vehicle 5.

Transition T1 starts at CP = 100% and ends at CP = 24%. When the CP value falls below 70% corresponding to a fixed threshold Th2, the state changes from depressed to depressed. As the clutch pedal position CP continues to decrease, the state remains pressed until the upper fixed limit Lu is crossed by 30%, at which point the state changes to released and remains in the released state until until it reaches the end of its change in a position where the position of the clutch pedal is 24%. Note that, in this state, the transition window lies on the pressed side of the clutch pedal position, CP = 24%, and that the trailing threshold Th1 is shifted to the pressed direction by 5%, so Th1 = 29%.

The transition window always lies on the side of the clutch pedal position, which will cause a change in state from released to pressed or from pressed to released.

Transition T2 is the displacement of the clutch pedal from 24% to 0% and accompanies transition T1. In this case, there will be no change in state since the state is already released and the position of the clutch pedal is moving towards the fully released position. The transition window will then follow the position of the clutch pedal towards the released position, but since the slave threshold Th1 lies on the pressed side of the clutch pedal position, there is no threshold for a state change that must be crossed.

Transition T3 is the displacement of the clutch pedal from 24% to 100% and accompanies transition T1.

As the value of the clutch pedal position increases, there is no change in state until the clutch pedal position is greater than the position of the driven threshold TH1. That is, when the position of the clutch pedal CP is greater than 29%, the state will change from released to depressed. As the clutch pedal position CP continues to increase, the state will remain depressed until the fixed threshold Th2 is 70% crossed. Above 70%, the state will change to depressed and remain in that state until the position of the clutch pedal reaches 100%.

Transition T4 starts at CP = 0% and ends at CP = 24%. As soon as the lower fixed limit L1 is crossed by 10%, the state changes from released to pressed and will remain in this state until the position of the clutch pedal reaches 24%. Since the position of the clutch pedal has moved from the released state towards the depressed state, the transition window lies on the released side of the position of the clutch pedal CP, and the driven threshold Th1 is shifted 5% towards the released state from the clutch pedal position CP. Therefore, although the position of the clutch pedal is the same as for transition T1, the location of the transition window is on the opposite side of the position CP of the clutch pedal.

The T5 transition occurs from 24% to 0% and accompanies T4.

The state of the clutch pedal position after the transition T4 is initially depressed, in contrast to the result from the transition T1 by 24%, which caused the released state.

While the position of the clutch pedal decreases, the condition remains the same until the driven threshold Th1 is reached by 19%. As soon as the slave threshold Th1 is crossed, the state changes to released and will remain in that state until the position of the clutch pedal reaches 0% of the fully released position of the clutch pedal 25.

When the value of the clutch pedal position falls below the current driven threshold Th1, it will cause the driven threshold Th1 to be thrown to the pressed side of the clutch pedal position, and the driven threshold will then track the position of the clutch pedal CP, 5% behind after the clutch pedal position has moved to more than 5% over the pre-set slave threshold Th1, until the slave threshold Th1 reaches the lower threshold value Ll.

Transition T6 accompanies transition T4.

The initial state is depressed, and this state is maintained until the fixed threshold Th2 is 70% crossed, after which it changes to the depressed state and remains depressed as the clutch pedal is further depressed to the fully depressed position, having value of 100%. Note that, since the driven threshold Th1 lies on the released side of the clutch pedal position, it cannot intersect. However, when the position of the clutch pedal increases from 24%, the driven threshold will follow until it reaches the maximum allowable value of 30% when the upper fixed limit Lu is reached.

The position of the transition window, and hence the slave threshold Th1, therefore, is always located on the side of the position of the clutch pedal, which, if the threshold Th1 is crossed while the clutch pedal position is within the transition zone, will cause a change in state from depressed to released, or vice versa.

Next, with reference to FIG. 4, a first embodiment of a method for generating a control terminal from an EC3P 16C using the dynamic coupling function according to this invention is shown.

The method, in general terms, comprises first setting the moving threshold Th1 at the upper limit Lu of its allowable range. The function is then re-executed and, at each execution, a new location for the sliding threshold (Thresh_tmp) is calculated to be a fixed offset, which, in this case, is 5% away from the current position of the clutch pedal (CP). If the new calculated location (Thresh_tmp) would be closer to the current position of the pedal (CP), then the new location is taken as the threshold position from Release to Depressed (Th1), otherwise, the previous value of the threshold Th1 is saved. In any case, the value for the threshold Th1 is limited by the upper and lower limits Lu, Ll, which, in this case, have values of 30% and 10%, respectively.

In detail, the method starts at step 100, in which the motor vehicle 5 is not operational, then, at step 105, an ignition key switch-on event occurs, including power to the motor vehicle systems and, in particular, to the electronic control unit 16 of the sensor 26 clutch pedals and EC3P 16C.

Then, at step 110, the EC3P 16C is initialized by setting Th1 equal to the fixed upper limit of Lu, namely 30%, this is usually achieved by ensuring that the clutch pedal 25 is fully depressed before the method can literally begin.

That is, in practice, there is an additional step 107 (not shown), where it is tested whether the clutch pedal 25 has been fully depressed and, if not, the method returns to the beginning of the cycle to step 105, and if it was, the method advances to step 110 with slave threshold set to Lu. After step 110, the method advances to decision step 115.

At decision block 115, the current position of the clutch pedal (CP) is compared to the sliding threshold Th1. If the CP value is the same or greater than Th1, then the result is to advance to step 120, while if the CP value is less than Th1, the result is to advance to step 130.

Considering the first case where the CP is greater than or equal to the displacement threshold value Th1, the method continues at step 120 by comparing the CP with Th2, which is a lower threshold for the squeezed area. If the CP is greater than or equal to Th2, the state is enabled in step 124 as being 'Depressed', and the corresponding control terminal is issued by the electronic control unit 16, and if the CP is less than Th2, the state is enabled in step 122 as being 'Pressed ', and the corresponding control terminal is issued to the electronic control unit 16. The nature of the control pin will depend on the specific design of the EC3P 16C, but could, for example, be a two-bit pin with the following notation: [00] indicates the state of the released position of the clutch pedal; [01] indicates the depressed state of the clutch pedal; and [11] indicates the depressed state of the clutch pedal.

Then, from steps 122 and 124, the method advances to step 125, where the time threshold Thresh_tmp is set to CP minus the transition bias (w%).

The method then advances to step 126, where the time threshold Thresh_tmp is compared with the current value of the tracking threshold Th1 and, if the value of Thresh_tmp is greater than Th1, the method advances to step 128, where Th1 is set to Thresh_tmp, and if Thresh_tmp is not greater than Th1 , then, at step 127, Th1 remains unchanged.

Returning to step 130, where the state is resolved as being 'Released', and the corresponding control terminal is issued from EC3P 16C to the electronic control unit 16, the method advances from step 130 to step 132.

At step 132, the time threshold Thresh_tmp is set to CP plus a transient offset (w%).

The method advances to step 134, where the time threshold Thresh_tmp is compared with the current value of the tracking threshold Th1 and, if the value of Thresh_tmp is less than Th1, the method advances to step 138, where Th1 is set to Thresh_tmp, and if Thresh_tmp is not less than Th1, then, at step 136, Th1 remains unchanged.

Following from any of steps 127, 128, 136 and 138, the method advances to step 140, where it is verified that the value Th1 derived from the previous step 127 or 128, or 136, or 138 is within the upper and lower limits of Lu and Ll , respectively. That is, if Th1 is greater than Lu, its value decreases to be equal to Lu, and, similarly, if the value of Th1 is less than Ll, its value increases to be equal to Ll.

The method then advances from step 140 to step 150, where it is checked whether the state of the ignition key is still present. If the state of the “on ignition key” is still present, indicating that the power remains on, the method returns to step 115, and steps 115 to 150 are repeated, otherwise, it ends at step 160. Steps 115 to 150 of the method are repeated every 20 to 50 ms, if only the power remains on.

Numerical examples of the operation of the method shown in FIG. 1 are set forth below based on the transitions shown in FIG. 6.

Transition T1, in which CP goes from 100% to 24%

Where:

CP * = 100% CP * is the value of the clutch pedal position on which the calculations are based.

In this case, the value of the position of the clutch pedal is 100.

Th1 = 30%. (Th1 cannot be greater than 30%, due to truncation step 140).

Th2 = 70% Ll = 10% Lu = 30%

Offset 'w' = 5%

Stage number Test or action Result 115 100≥30 Yes, go to 120 120 100≥70 Yes, go to 124 124 State = D Output State Pressed 125 100-5 Thresh_tmp = 95 126 95> 30 Yes, go to 128 128 Set Th1 = 95 Th1 = 95 140 Trim Th1 Th1 = 30

Transition T1, in which CP goes from 100% to 50%

Where: CP * = 50%

Th1 = 30%. (Th1 cannot be greater than 30%, due to truncation step 140).

Th2 = 70% Ll = 10% Lu = 30%

Offset 'w' = 5%

Stage number Test or action Result 115 50> 30 Yes, go to 120 120 50> 70 No, go to 122 122 State = P Output State Pressed 125 50-5 Thresh_tmp = 45 126 45> 30 Yes, go to 128 128 Set Th1 = 45 Th1 = 45 140 Trim Th1 Th1 = 30

Transition T1, in which the CP value goes from 50% to 24%

Where: CP * = 24%

Th1 = 30%. (Th1 cannot be greater than 30%, due to truncation step 140).

Th2 = 70% Ll = 10% Lu = 30%

Offset 'w' = 5%

Stage number Test or action Result 115 24≥30 No, go to 130 130 State = R Output Status Released 132 24 + 5 Thresh_tmp = 29 134 29 <30 Yes, go to 138 138 Set Th1 = 29 Th1 = 29

Therefore, at the end of transition T1, the clutch state is set to Release, the clutch pedal position is 24%, the transition window lies on the pressed side of the clutch pedal position with the slave threshold Th1 located at a distance of 5% from the clutch pedal position.

Transition T2, in which CP goes from 24% to 20%

Where: CP * = 20%

Th1 = 29% Th2 = 70% Ll = 10%

Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 20≥29 No, go to 130 130 State = R Output Status Released 132 20 + 5 Thresh_tmp = 25 134 25 <29 Yes, go to 138 138 Set Th1 = 25 Th1 = 25

Therefore, there was no change in state, but the tracking threshold followed the position of the clutch pedal in order to leave a 5% offset with the transition window on the pressed side of the clutch pedal position.

Transition T2, in which CP goes from 20% to 0%

Where:

CP * = 0% Th1 = 25% Th2 = 70%

Ll = 10% Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 0≥25 No, go to 130 130 State = R Output Status Released 132 0 + 5 Thresh_tmp = 5 134 5 <25 Yes, go to 138 138 Set Th1 = 5 Th1 = 5 140 Trim Th1 Th1 = 10

Therefore, there was no change in state, and the tracking threshold Th1 was prevented from falling below 10%, the transition window remains on the pressed side of the clutch pedal position, but, in this case, is 10% off due to the cutting effect in step 140.

Transition T3 in which CP goes from 24% to 28%

Where:

CP * = 28% Th1 = 29% Th2 = 70%

Ll = 10% Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 28> 29 No, go to 130 130 State = R Output Status Released 132 28 + 5 Thresh_tmp = 33 134 33 <29 No, go to 136 136 Set Th1 = Th1 Th1 = 29

Therefore, there were no changes in state, and the Th1 tracking threshold did not move, but, in this case, is located at 1% off.

Transition T3 in which CP goes from 28% to 29.5% Where:

CP * = 29.5% Th1 = 29% Th2 = 70%

Ll = 10% Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 29.5≥29 Yes, go to 120 120 29.5≥70 No, go to 122 122 State = P Output State Pressed 125 29.5-5 Thresh_tmp = 24.5 126 24.5> 29 No, go to 127 127 Set Th1 = Th1 Th1 = 29

Therefore, there was a change in state, and the tracking threshold Th1 remained the same. The transition window is thrown from the pressed side of the clutch pedal position to the released side of the clutch pedal position, so that the tracking threshold remains on the side of the clutch pedal position, in which a state change will occur if it is crossed.

Note that, in this case, the tracking threshold is located at 0.5% off. In practice, the hysteresis zone is used to prevent multiple switching when the position of the clutch pedal is, say, within 3% of the tracking threshold after the tracking threshold has been crossed.

Transition T3 in which CP goes from 29.5% to 50% Where:

CP * = 50% Th1 = 29% Th2 = 70%

Ll = 10% Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 50> 29 Yes, go to 120 120 50> 70 No, go to 122 122 State = P Output State Pressed 125 50-5 Thresh_tmp = 45 126 45> 29 Yes, go to 128 128 Set Th1 = 45 Th1 = 45 140 Trim Th1 Th1 = 30

Therefore, there were no state changes, and the tracking threshold Th1 was cut to 30. The transition window remained on the released side of the clutch pedal position, so that the monitoring threshold remains on the clutch pedal position, in which the state change will occur if it is crossed.

Transition T3 in which CP goes from 50% to 100%

Where:

CP * = 100% Th1 = 30% Th2 = 70%

Ll = 10% Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 100≥30 Yes, go to 120 120 100≥70 Yes, go to 124 124 State = D Output State Pressed 125 100-5 Thresh_tmp = 95 126 95> 30 Yes, go to 128 128 Set Th1 = 95 Th1 = 95 140 Trim Th1 Th1 = 30

There was a change of state from depressed to depressed, since the upper fixed threshold Th2 was crossed and the tracking threshold Th1 was reduced to 30. The transition window remains on the side of the clutch pedal position, in which the state change will occur if it is crossed.

Transition T4 in which CP goes from 0% to 14%

Where:

CP * = 14% Th1 = 10% (due to cutting)

Th2 = 70% Ll = 10% Lu = 30%

Offset 'w' = 5%

Stage number Test or action Result 115 14≥10 Yes, go to 120 120 14≥70 No, go to 122 122 State = P Output State Pressed

125 14-5 Thresh_tmp = 9 126 9> 10 No, go to 127 127 Set Th1 = Th1 Th1 = 10

There was a change of state from released to depressed, since the lower limit Ll was crossed, and the tracking threshold Th1 remains at 10. The transition window remains on the side of the clutch pedal position, in which the state change will occur if it is crossed, but has thrown over starting position, now it lies on the released side of the clutch pedal position.

Transition T4 in which CP goes from 14% to 18%

Where:

CP * = 18% Th1 = 10% (Due to cutting) Th2 = 70%

Ll = 10% Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 18≥10 Yes, go to 120 120 18≥70 No, go to 122 122 State = P Output State Pressed 125 18-5 Thresh_tmp = 13 126 13> 10 Yes, go to 128 128 Set Th1 = 13 Th1 = 13

The state of the clutch pedal remains depressed since the trailing threshold has not been crossed since the position of the clutch pedal moves from the trailing threshold Th1. Defect Th1 is now assigned 5% of the clutch pedal position to the clutch pedal position side, which, if crossed, would cause a state change.

Transition T4 in which CP goes from 18% to 24%

Where:

CP * = 24% Th1 = 13% Th2 = 70%

Ll = 10% Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 24≥13 Yes, go to 120 120 24≥70 No, go to 122 122 State = P Output State Pressed 125 24-5 Thresh_tmp = 19 126 19> 13 Yes, go to 128 128 Set Th1 = 19 Th1 = 19

The state of the clutch pedal position remained unchanged, and the driven threshold tracked the position of the clutch pedal to remain offset by 5% of it. The transition window lies on the released side of the clutch pedal position.

Note that, in this state, the driven threshold is located on the released side of the clutch pedal position at 19%, while in case of transition 1, with regard to the same clutch pedal position, the driven threshold lies on the pressed side of the clutch pedal position at the location 29%

Transition T5 in which CP goes from 24% to 18%

Where:

CP * = 18% Th1 = 19% Th2 = 70%

Ll = 10% Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 18≥19 No, go to 130 130 State = R Output Status Released 132 18 + 5 Thresh_tmp = 23 134 23 <19 No, go to 136 136 Set Th1 = Th1 Th1 = 19

Since the slave threshold Th1 was crossed, the state changed from pressed to released, but the threshold was not moved, since the position of the clutch pedal is not more than 5% lower than the current position of the slave threshold. Note that the transition window now lies on the pressed side of the clutch pedal position, having thrown when the driven threshold Th1 has been crossed. Note that, in practice, a hysteresis zone would be provided, so that small changes back in the direction of the pressed state would not cause multiple switching.

Transition T5 in which CP goes from 18% to 12%

Where:

CP * = 12% Th1 = 19% Th2 = 70%

Ll = 10% Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 12≥19 No, go to 130 130 State = R Output Status Released 132 12 + 5 Thresh_tmp = 17 134 17 <19 Yes, go to 138 138 Set Th1 = 17 Th1 = 17

There were no state changes, and the transition window remains on the pressed side of the clutch pedal position, but the driven threshold began to monitor the clutch pedal position in order to stay 5% behind it.

Transition T5 in which CP goes from 12% to 0%

Where:

CP * = 0% Th1 = 17% Th2 = 70%

Ll = 10% Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 0≥17 No, go to 130 130 State = R Output Status Released 132 0 + 5 Thresh_tmp = 5 134 5 <17 Yes, go to 138 138 Set Th1 = 5 Th1 = 5 140 Trim Th1 Th1 = 10

The state of the clutch pedal position has not changed, and the transition window remains on the pressed side of the clutch pedal position, but the driven threshold is limited to remain at 10%.

Transition T6, in which CP goes from 24% to 28%

Where:

CP * = 28% Th1 = 19% Th2 = 70%

Ll = 10% Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 28≥19 Yes, go to 120 120 28≥70 No, go to 122 122 State = P Output State Pressed 125 28-5 Thresh_tmp = 23 126 23> 19 Yes, go to 128 128 Set Th1 = 23 Th1 = 23

There were no state changes, but the driven threshold has moved in order to track the position of the clutch pedal.

Transition T6, in which CP switches from 28% to 50% Where:

CP * = 50% Th1 = 23% Th2 = 70%

Ll = 10% Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 50 ≥ 23 Yes, go to 120 120 50 ≥ 70 No, go to 122 122 State = P Output State Pressed 125 50-5 Thresh_tmp = 45 126 45> 23 Yes, go to 128 128 Set Th1 = 45 Th1 = 45 140 Trim Th1 Th1 = 30

There was no change in state, the transition window still lies on the released side of the clutch pedal position, but the driven threshold is now fixed at the upper limit of Lu due to cutting.

Transition T6, in which CP goes from 50% to 100%

Where:

CP * = 100% Th1 = 30% Th2 = 70%

Ll = 10% Lu = 30% Offset 'w' = 5%

Stage number Test or action Result 115 100≥30 Yes, go to 120 120 100≥70 Yes, go to 124 124 State = D Output State Pressed 125 100-5 Thresh_tmp = 95 126 95> 30 Yes, go to 128 128 Set Th1 = 95 Th1 = 95 140 Trim Th1 Th1 = 30

The driven threshold Th1 remains limited by trimming at the upper limit of Lu, but there has been a change in state due to the position of the clutch pedal crossing the fixed upper threshold Th2.

According to a second embodiment of the invention, a small correction (δ), which would typically be 0.01%, is made with respect to the threshold position (Th1) in each execution cycle to move the threshold from the current position of the clutch pedal (CP). The idea is to increase the separation between the sliding threshold Th1 and the current position CP of the clutch pedal up to the offset value, for example, if the driver’s foot has slowly moved to the sliding value Th1. Inadvertent changes in the position of the clutch pedal are often referred to as the 'slow movement' of the clutch pedal. The impact of correction is negligible compared to changes resulting from normal pedal movements, but prevents the occurrence of incorrect state changes rather as a result of a gradual slow movement than the actual intention of the driver.

The flowchart of FIG. 5 shows in more detail a second embodiment of a method using a dynamic adhesion function with added 'slow movement' correction.

The method begins at step 200, in which the motor vehicle 5 is not operational, then, at step 205, an ignition key activation event occurs, including power to the motor vehicle systems and, in particular, to the electronic control unit 16, the clutch pedal sensor 26 and EC3P 16C.

Then, at step 210, the EC3P 16C is initialized by setting Th1 equal to the fixed upper limit of Lu, namely 30%, this is usually achieved by ensuring that the clutch pedal 25 has been fully depressed before the method can literally begin. That is, in practice, there is an additional step 207 (not shown), where it is checked whether the clutch pedal 25 has been fully depressed, and if not, the method returns to the beginning of the cycle to step 205, and if it was, the method advances to step 210 with a slave threshold set to Lu. After step 210, the method advances to decision step 215.

At decision block 215, the current position of the clutch pedal (CP) is compared with the sliding threshold Th1. If the CP is the same or greater than Th1, then the result is to advance to step 220, and if the CP is less than Th1, the method advances to step 230.

Considering the first case where the CP is greater than or equal to the moving threshold Th1, the method continues at step 220 by comparing the CP with Th2, which is a lower threshold for the squeezed zone. If the CP is greater than or equal to Th2, the state is resolved at 224 as being 'Depressed', and the corresponding control terminal is issued by the electronic control unit 16, and if the CP is less than Th2, the state is resolved at 222 as being 'Pressed ', and the corresponding control terminal is issued to the electronic control unit 16.

Then, from steps 222 and 224, the method advances to step 225, where the time threshold Thresh_tmp is set to CP minus the transient offset (w%).

The method advances to step 227, where the time threshold Thresh_tmp is compared with the current value of the tracking threshold Th1 minus the creep correction δ and, if the Thresh_tmp value is greater than Th1 minus δ, the method advances to step 229, where Th1 is set to Thresh_tmp, and if, to at step 227, Thresh_tmp is not greater than Th1 minus δ, then, at step 228, Th1 is set to Th1 minus δ.

Returning to step 230, where the state is resolved as being 'Released', and the corresponding control terminal is issued from EC3P 16C to the electronic control unit 16, the method advances from step 230 to step 232.

At step 232, the time threshold Thresh_tmp is set to CP plus a transient offset (w%).

The method advances to step 235, where the time threshold Thresh_tmp is compared with the current value of the tracking threshold Th1 plus creep correction δ and, if the Thresh_tmp value is less than Th1 plus δ, the method advances to step 239, where Th1 is set to Thresh_tmp, and if, to at step 235, the value of Thresh_tmp is not less than Th1 plus δ, then, at step 237, Th1 is set to Th1 plus δ.

Following from any of steps 228, 229, 237 and 239, the method advances to step 240, where it is verified that the value Th1 derived from the previous step 228 or 229, or 237, or 239 is within the upper and lower limits of Lu and Ll , respectively. That is, if Th1 is greater than Lu, its value decreases to be equal to Lu, and, similarly, if the value of Th1 is less than Ll, its value increases to be equal to Ll.

The method then advances from step 240 to step 250, where it is checked whether the state of the ignition key is still present. If the state of the “on ignition key” is still present, indicating that the power remains on, the method returns to step 215, and steps 215 to 250 are repeated, otherwise, it ends at step 260. Steps 215 to 250 of the method are repeated every 20 to 50 ms, if only the power remains on.

Those skilled in the art will appreciate that, although the invention has been described as an example with reference to one or more embodiments, it is not limited to the disclosed embodiments, and that one or more modifications with respect to the disclosed embodiments or alternative embodiments could be invented without leaving the scope of the invention.

For example, the clutch engagement state could be logically displayed not directly on the clutch pedal, but on the lever of the clutch release mechanism or another part of the clutch release mechanism.

Although the invention has been described above with respect to the use of a simple single value for a threshold between the Pressed and Released areas, those skilled in the art should take into account that, as inferred above, a single value for a moving threshold can be favorably replaced by two values that work as hysteresis pair. Thus, the threshold from Depressed to Release would be slightly different from the threshold from Release to Depressed, and this would prevent a quick change in the indicated state of the clutch pedal between Release and Depressed, or vice versa, if the pedal was held close to the sliding threshold.

Moreover, although the invention has been described with reference to a particularly useful use with respect to a start-stop system of a motor vehicle, it should be appreciated that other motor-based systems may require an indication of the position of the clutch pedal, and that the invention can be applied to any such uses of a motor vehicle where the state of the clutch pedal position is required.

Claims (22)

1. A method of generating a control terminal from a clutch position reading system, wherein the method consists in controlling the position of the clutch pedal of a motor vehicle, determining a transition zone defined by a range of clutch pedal positions in which the control terminal is one of two alternative position states clutch pedals containing the released state of the clutch pedal and the depressed state of the clutch pedal set the offset of the sliding threshold from the initial position of the pedal sts prisoners, which, if crossed, when the position of the clutch pedal is in the transition zone, will cause a change in state of the clutch pedal position and the change in control output from the current state to an alternative state, if crossed by a sliding door. 2. The method according to claim 1, wherein the method further comprises setting the maximum shift of the sliding threshold from the position of the clutch pedal. 3. The method according to p. 1 or 2, in which, if the state of the clutch pedal is a released state in the initial position of the clutch pedal, then the value of the sliding threshold will have a value greater than the value of the initial position of the clutch pedal. 4. The method according to p. 1 or 2, in which, if the state of the clutch pedal is the pressed state in the initial position of the clutch pedal, then the value of the sliding threshold will have a value less than the value of the initial position of the clutch pedal. 5. The method according to claim 1 or 2, wherein when the position of the clutch pedal and the sliding threshold are both in the transition zone, the method further comprises moving the sliding threshold so as to maintain a predetermined offset from the position of the clutch pedal, if the position the clutch pedal moves from the initial position of the clutch pedal from a sliding threshold. 6. The method according to claim 1 or 2, in which, if the position of the clutch pedal moves from the initial position of the clutch pedal to the sliding threshold, the value of the sliding threshold remains the same until the position of the clutch pedal has moved a predetermined distance beyond the sliding threshold. 7. The method according to claim 1 or 2, in which the transition zone is limited at the lower end to the lower limit of the position of the clutch pedal, and at the upper end to the upper limit of the position of the clutch pedal. 8. The method according to claim 7, in which the released zone is defined by the range of the clutch pedal positions, limited to the fully released clutch pedal position at one end and the lower limit of the clutch pedal position at the upper end, and the control terminal always indicates the released clutch pedal position times when the position of the clutch pedal is within the released zone and the pressed zone is determined by the range of clutch pedal positions limited at one end by the upper redistribution of the clutch pedal position and bounded on the opposite end of the fixed upper threshold, and the control terminal always indicates the pressed state of the clutch pedal position whenever the position of the clutch pedal is pressed within the zone. 9. The method according to claim 8, in which the depressed zone is determined by the range of the clutch pedal, limited at one end by a fixed upper threshold, and at the opposite end by the fully depressed clutch pedal position, and the control terminal always indicates the released state of the clutch pedal position, when the position of the clutch pedal is within the squeezed area. 10. The method according to p. 8 or 9. in which the offset of the sliding threshold from the initial position of the clutch pedal determines the transition window, limited at one end by the position of the sliding threshold, and at the opposite end by the initial position of the clutch, and the transition window is always located on the side of the initial clutch position towards the clutch position zone of the alternate clutch position state. 11. The method according to claim 1 or 2, wherein the method further comprises adjusting the sliding threshold by a very small amount each time the sliding threshold is calculated to allow for inadvertent changes in the position of the clutch pedal. 12. The method according to claim 11, in which the correction of the sliding threshold is that increase the offset from the initial position of the clutch pedal to the sliding threshold by a very small amount each time the sliding threshold is calculated. 13. The method according to p. 12, in which, if the magnitude of the sliding threshold is greater than the initial position of the clutch, the offset is increased by adding a very small value to the current value of the sliding threshold. 14. The method according to p. 12, in which, if the magnitude of the sliding threshold is less than the initial position of the clutch, the offset is increased by subtracting a very small value from the current value of the sliding threshold. 15. The method of claim 11, wherein the very small value is less than 1% of the offset value. 16. The method according to claim 1 or 2, wherein the method further comprises supplying a control output from the clutch position reading system to the start-stop system of the motor vehicle for use in controlling the stop and start of the engine of the motor vehicle. 17. The clutch position reading system for sensing the position of the clutch pedal of the motor vehicle and providing a control output indicating the position status of the clutch pedal, the system includes position sensing means for providing a signal indicating the current position of the clutch pedal and an electronic clutch pedal position processor for processing the signal from the means read position, in this case, if the position of the clutch pedal is within the transition zone, limited fixed the lower limit of the position of the clutch pedal and the upper fixed limit of the position of the clutch pedal, in which the state of the clutch pedal position is one released and depressed, the electronic clutch pedal position processor is configured to set the offset of the sliding threshold from the initial position of the clutch pedal, which, if crossed, when the position of the clutch pedal is within the transition zone, it will cause a change in the state of the clutch pedal position and a change in the control output eniya with indicating the current state of the clutch pedal to the alternative state indicating a position of the clutch pedal, if crossed by a sliding door. 18. The system of claim 17, wherein if the clutch pedal is in the released state in the initial position of the clutch pedal, the electronic clutch pedal position processor is configured to set a sliding threshold value so that it has a value greater than the value of the initial position the clutch pedal, and if the clutch pedal is depressed in the initial position of the clutch pedal, the electronic clutch pedal position processor is configured to set a sliding threshold value so that it has a value less than the value of the initial position of the clutch pedal. 19. The system of claim 17 or 18, wherein the electronic clutch pedal position processor is configured to set a maximum displacement of the sliding threshold from the clutch pedal position. 20. The system of claim 17 or 18, wherein the electronic clutch pedal position processor is further configured to adjust the sliding threshold by a very small amount each time the sliding threshold is calculated to allow for inadvertent changes in the position of the clutch pedal. 21. The system of claim 17 or 18, wherein the electronic clutch pedal position processor is configured to provide a control output from the clutch pedal position sensing system to a start-stop system of a motor vehicle for use in controlling a stop and start of an engine of a motor vehicle. 22. A motor vehicle having an engine, clutch, the gearing state of which is controlled by the clutch pedal, a system for automatically starting and stopping the engine based on at least changes in the position of the clutch pedal, and a clutch position reading system for reading the clutch pedal position according to any one of paragraphs. 17-21.

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