FR2863327A1 - Internal combustion engine and gearbox coupling device for use in vehicle, has actuator controlling module with correcting unit to find control signal for canceling variation between nominal value and measure of clutch control quantity - Google Patents

Abstract

The device has an actuator controlling module (26) to control an actuator (24) of a clutch (14). The module has a correcting unit to determine a control signal of the actuator for canceling variation between a nominal value and measure of a clutch control quantity in minimum amount of time. An adjusting unit adjusts parameters of the correcting unit according to physical quantities and actual behavior of the actuator.

Description

The invention relates to an adaptive device controlled coupling

  between an engine and a gearbox in a motor vehicle.

  Such a device comprises a coupling means between the output shaft of the internal combustion engine of the motor vehicle and an input shaft of the gearbox which can be of the mechanical type with several transmission ratios with or without robotization of the changes of reports.

  The coupling means is generally a friction clutch, controlled by an actuator driven by an information processing system according to a certain number of measured or estimated parameters such as positions, speeds, accelerations, stresses, torques, pressures and electrical voltages.

  The clutch control actuator acts on the position of a movable member of this clutch, such as for example the clutch abutment, which determines the position of a pressure plate and the load applied to this plate by an annular diaphragm for clamping the friction linings of a disc connected to an input shaft of the gearbox, this tightening determining the torque transmitted by the clutch.

  The actuator can also act directly on the load applied to the pressure plate by a mechanical or hydraulic connection for example. Automated clutch control shall take into account a large number of physical quantities, state variables and control variables that are measured or estimated on the engine, the gearbox and the rest of the vehicle, and signals representing the will of the driver, the adaptation of the behavior of the transmission to the driving style of the driver, the dynamic state of the vehicle and the state of the control device (initialization, normal mode, degraded mode, learning, stopping, ...) etc. It has already been proposed to control the clutch to make it transmit a desired torque, but the torque transmitted by the clutch varies non-linearly depending on the pressure or the position of a control member of the clutch, such as the clutch abutment for example, it varies from one clutch to another due to manufacturing dispersions, and it also varies according to a number of parameters such as temperature, the state of the fittings and friction surfaces of the clutch mechanism, etc.

  It is therefore extremely difficult, if not impossible, to control the clutch in a correct manner to make it transmit a desired torque that has been determined by means of computing and information processing.

  The present invention proposes a solution to this problem which consists in controlling the clutch linearly transmissible torque by means of a shared control device in several control modules which are intended to compensate in cascade dispersions of the various components of the transmission of the vehicle and which comprise: a transmission supervision module implementing driving pleasure management strategies which control the clutch in torque and / or the vehicle engine in speed and / or in torque and which are intended to compensate for the variability of the dynamic behavior of the engine, the gearbox and the rest of the vehicle, in particular the components of the transmission connected to the driving wheels of the vehicle, - a module for controlling the clutch in torque which enables to determine, among other things, a good setpoint value of a physical quantity of internal or external control of the clutch in order to obtain a tr desired quantity in the clutch as a function of a torque setpoint to be transmitted, delivered by the transmission supervision module, and various signals of physical, state or control variables which are measured on the motor, on the gearbox and on the rest of the vehicle, - and a control module of a clutch actuator, which makes it possible to control the actuator to obtain a physical quantity of internal or external control of the clutch as a function of a setpoint supplied by the torque control module of the clutch and various physical, state or control signals which are measured on the engine, on the gearbox and on the rest of the vehicle.

  Thus, the actuator and its control module are seen as nearly perfect by the torque control module of the clutch, and the clutch and its control module are themselves seen as nearly perfect by the a supervision module that manages the clutch and engine control strategies taking into account the dynamic behavior of the engine, the gearbox and the rest of the vehicle.

  By sharing this control device in three modules that compensate for each of the variability in the behavior of different elements or members, the overall performance of the device is improved and more account is taken of the variations of the parameters representative of the state or the control. various components of the vehicle transmission.

  The actuator control module comprises corrective means which determine a control value of the actuator making it possible to cancel, in a minimum of time, the difference between the set value determined by the clutch control module and a measurement of the physical control quantity of the clutch, and means for adjusting the parameters of the corrective means as a function of variations in physical physical quantities of the environment such as the temperature and / or a supply voltage or phenomena such as aging and wear of the actuator components and the clutch control.

  Such an actuator control module makes it possible to compensate for variations in the behavior of the actuator and the control of the clutch, which are due to variations in physical magnitudes such as, for example, that the temperature and a supply voltage and the effects of wear and aging of the internal actuator and clutch control components, all of which change the static and dynamic responses of the actuator and the clutch control.

  The torque control module of the clutch therefore does not have to correct the response differences of the system formed by the actuator and the control of the clutch, which results in an increase in its performance.

  In the actuator control module, the correction means comprise means for filtering and scaling the setpoint value provided by the torque control module of the clutch and the measurement of the physical quantity. for controlling the clutch, said filtering and scaling means being connected to a comparator determining the difference between the reference value and the measurement, and an adapter receiving the difference signal supplied by the comparator and modifying it according to the output signals of the aforementioned adjustment means.

  The corrective means of the actuator control module also comprise means for calculating a pre-positioning or an anticipation of the control signal of the actuator, these calculation means receiving the aforementioned reference value and the signals output of the adjustment means and generating a pre-positioning or anticipation control which is added to the output signal of the aforementioned adapter.

  This pre-positioning or anticipation makes it possible to directly position the control of the actuator with great speed.

  The signal resulting from the addition of the pre-positioning or anticipation and the output signal of the adapter is applied to a scaling circuit whose output signal constitutes the control signal of the actuator , and the parameters of the filtering and scaling means of the correcting means are adjusted by the aforesaid adjustment means which receive, as input, measurements of physical quantities affecting the dynamic response and the accuracy of the actuator, the measurement the physical size of the clutch control and the control signal of the actuator.

  These adjustment means comprise means for calculating the parameters of a mathematical model of the actuator as a function of measured values of the physical quantities, the state and the control of the clutch and the actuator, and means for adapting the parameters of the components of the correcting means to the actual behavior of the actuator.

  In a preferred embodiment, these adjustment means comprise a memory in which are stored tables of values of the parameters of the components of the aforesaid corrective means, and means of selection in these tables of the values of parameters best suited to the dynamic behavior. actual actuator, and / or formulas for calculating these parameters.

  The invention also applies, of course, to the control of the coupling between the output shaft of a vehicle engine and a robotized gearbox which comprises two input shafts in parallel each connected by a clutch. to the engine output shaft of the vehicle.

  In this case, each clutch is controlled by an actuator itself controlled by an actuator control module and by a torque control module of the clutch.

  The invention will be better understood and other characteristics, details and advantages thereof will appear more clearly on reading the description which follows, given by way of example with reference to the accompanying drawings, in which: FIG. a block diagram of a vehicle equipped with a device according to the invention in the case of a gearbox with a single input shaft; - Figure 2 is a block diagram of a vehicle equipped with an alternative embodiment of the device according to the invention in the case of a robotized gearbox with two parallel input shafts; FIG. 3 is a schematic representation of the essential characteristics of the device according to the invention; - Figure 4 schematically shows a control module of the actuator of the clutch.

  FIG. 1 diagrammatically shows a motor vehicle equipped with a device according to the invention, the reference 10 denoting an internal combustion engine whose output shaft 12 is connected by a clutch 14 to the input shaft 16 a gearbox for example robotized 18 which is of the mechanical type with several transmission ratios and whose output shaft 20 is connected to driving wheels of the vehicle 22.

  The clutch 14 is controlled by an actuator 24, which acts for example on the position of a clutch abutment. In a manner well known to those skilled in the art, this clutch abutment acts itself on radial fingers of an annular diaphragm which is carried by a clutch cover and which acts axially on a pressure plate of the clutch for clamping the friction linings of a disk rotatably connected to the input shaft 16 of the gearbox. It can also be a clutch open at rest, the actuator performing the clamping of the linings by mechanical or hydraulic means.

  The toppings can work dry or in oil.

  The actuator 24 is of any type, for example electric motor, hydraulic cylinder, or other.

  The device according to the invention comprises a module 26 for controlling the actuator 24, this module 26 receiving a setpoint signal generated by a module 28 for controlling the clutch in torque, this module 28 receiving a torque command signal transmittable by the clutch provided by a transmission supervision module 30 which also provides control and setpoint signals to a system 32 for driving the engine 10 of the vehicle.

  Information 34 from the vehicle, the engine and / or the control system 32, and the gearbox, for example such as the rotational speed of the engine, the torque supplied by the engine, the amount of fuel, the amount of air, transmission ratio used, ambient temperature, coolant temperature, vehicle speed, rotational speed of the transmission input shaft, vehicle wheel speed , the voltage supplied by the vehicle's battery, etc. are applied to the actuator control module 26, to the torque clutch control module 28, to the transmission supervision module 30 and to the vehicle engine control system 32.

  Information 36 relating to the actuator 24 and the clutch 14, such as values of force, pressure, position of a movable member of the actuator, position of the clutch abutment, tension electrical current, electrical current intensity, temperature, etc ... are applied to inputs of the actuator control module 26.

  Information 38 applied to inputs of the transmission supervision module 30 includes signals for managing and adapting transmission control strategies, relating to the operation of the vehicle, to the intentions of the driver, to the automatic control mode of the transmission. transmission, adaptability of transmission behavior, comfort and performance levels, etc.

  The transmission supervision module 30 generates, on the basis of this information and management strategies stored in memory, control and / or setpoint signals 40 which are applied to the control system 32 of the engine 10, and signals 42 setpoint applied to the torque control module 28 of the clutch 14, the signals 42 comprising a torque command signal transmissible by the clutch 14.

  The clutch control module 28 receiving these signals 42 and the information 34 provided by the engine 10, the gearbox 18 and the rest of the vehicle 22, generates a signal 44 for controlling the actuator control module 26. 24, the signal 44 being a reference signal of the control parameter of the clutch 14 such as for example the position of the clutch abutment.

  The actuator control module 26 receives this setpoint signal 44, the information supplied by the engine 10, the gearbox 18 and the remainder of the vehicle 22, and information 36 relating to the clutch 14 and to its actuator 24 and generates a signal 46 for controlling the actuator 24.

  In the variant embodiment shown in FIG. 2, there are substantially the same components and modules as in the embodiment of FIG. 1, the difference being that the gearbox 18 comprises two parallel input shafts 16, each connected by a clutch 14 to the output shaft 12 of the motor 10, each clutch being controlled by its actuator 24 itself controlled by a control module 26 of the aforementioned type and a module 28 for controlling the torque of the corresponding clutch.

  The two torque control modules 28 are controlled by the same transmission supervision module 30 which also controls the engine control system 10.

  Figure 3 is a schematic illustration of the essential features of the device according to the invention.

  The torque control module 28, which receives a torque command signal 42 transmissible by the clutch and which generates a command value signal 44 of a control parameter applied to the actuator control module 26, generates this signal from a learned curve A which is a curve of variation of the reference signal of the control parameter of the clutch 14 as a function of the signal 44, that is to say of the desired transmissible torque. This curve A is the inverse of the curve B of variation of the torque Tt which is transmitted by the clutch as a function of its control parameter P, which is for example the position of the clutch abutment.

  It can be seen that the curve B is not a linear variation of the control parameter P and that its slope varies between its ends from a low value to a high value. In addition, the curve B varies from one vehicle to another because of the manufacturing dispersions of the components of the clutch, it also varies with time, because of the temperature variations of its components, their degree of wear, characteristics of the components of the clutch mechanism, etc.

  The essential advantage of the device according to the invention is to linearize the control of the clutch thanks to the use in the control module 28 of a characteristic curve A which is the inverse of the characteristic curve B of operation of the clutch. 'clutch. This series combination of the two characteristic curves makes it possible to obtain, as represented in the right-hand part of FIG. 3, a characteristic C of linear variation of the torque Tt transmitted by the clutch as a function of the desired transmissible torque, ie say of the signal 42 torque setpoint transmissible by the clutch.

  Comfort steering, represented by the curve of torque or acceleration during the operation of the clutch, is thus simpler, more efficient and achievable in real time.

  The characteristic curve A used by the torque control module 28 is a learned curve, determined by calculation from measured or estimated values of the transmitted torque Tt and of the control parameter P and of a simple mathematical model of the characteristic curve. This makes it possible to follow the evolution of this characteristic curve and to take into account the variations of the parameters which determine it.

  An embodiment of the control module 26 of the actuator 24 is shown schematically in FIG.

  The dynamic response and accuracy of the actuator are affected by physical quantities such as temperature, supply voltage, and the effects of wear and aging of the internal components of the actuator and the control of the actuator. the clutch of the control 14.

  The variability generated by the actuator would require the torque control module 28 to correct the response deviations of the complete system, which would reduce the regulation performance of this module.

  The torque control module 26 of the actuator is responsible for compensating for variations in the physical process of actuating and controlling the clutch.

  The clutch control module 28 provides a reference signal 44 for the physical control quantity of the clutch, which is compared by a comparator 50 to a measurement or estimate 52 of this physical quantity, obtained from measurements. on the clutch 14.

  Corrective means described in detail in the following are used to determine the best value of the control signal 46 of the actuator to cancel the difference between the setpoint 44 and the measurement 52 by minimizing the time taken by the actuator to cancel this gap.

  The parameters of the correcting means of the module 26 are adjusted by means 54 which take into account the aging of the actuator and the clutch, the manufacturing dispersions and the variations of the physical environmental quantities 56 which are likely to disturb the operation of the actuator 24 and the clutch.

  More specifically, the module 26 shown in FIG. 4 comprises means 58 for scaling and filtering the reference signal 44, the output of the means 58 being applied to an input of the comparator 50, another input of which receives the measured value. 52 of the physical control quantity of the clutch after treatment by means of 60 scaling and filtering.

  The output of the comparator 50 is connected to an input of adapter means 62, another input of which is connected to an output of the adjustment means 54. The output of the adapter means 62 is connected to an input of a summator 64, of which another input receives an output signal of means 66 for pre-positioning or anticipating the value of the control signal of the actuator 24 as a function of the reference signal 44 supplied by the clutch torque control module 28.

  The pre-positioning essentially consists in determining from a current value a command making it possible to arrive very quickly in the vicinity of a final value, whereas the anticipation consists in determining an order from the preceding variations of 'a value, that is to say from the derivatives of this value.

  The output of the summator 64 is connected to scaling means 68 for providing a control signal 46 of the actuator 24, which is also applied to an input of the adjustment means 54, as well as the measurement 52 of FIG. the physical size of the clutch control.

  Control signals 70 required are also applied to an input of the adjusting means 54. The output signal of the pre-positioning or anticipating means 66 is added to the output of the adapter means 62 by the summator 64, this pre-setting. positioning or anticipation to position the control of the actuator 24 with great speed.

  The adapter means 62 serves to adjust the value of the control to compensate for model errors, disturbances and dispersions.

  For example, when the actuator 24 is an electromechanical jack that moves a clutch abutment and is controlled by a current-driven electric motor, the pre-positioning or anticipation means 66 can provide a minimum current setpoint. to move the clutch abutment as a function of the stop position setpoint to be achieved instead of waiting for an integrator of the adapter means 62 to slowly rise to the correct value.

  When the actuator 24 is a fluid distributor controlled by a solenoid valve, the pre-positioning or anticipation means 66 make it possible to apply a greater electrical voltage to control the opening of the solenoid valve more rapidly, the adapter means 62 correcting the fluid flow or pressure to achieve or maintain the desired position of the clutch abutment.

  The scaling means 58, 60, 68 and scaling means forming part of the pre-positioning or anticipating means 66 may have a variable gain and offset which are determined by the means of scaling. adjustment 54 to adapt the resolution of the setpoint value 44, i.e. the number of points available in the range of variation of the physical control quantity of the clutch. For example, in the case of the control of a dry clutch, the useful stroke defined between the engaged position and the licking point (position of contact between the friction and the plate where the clutch begins to transmit a non-zero torque ) varies over time with the wear of the clutch. The licking point is determined by learning.

  The adjustment of the gain and the offset of the scaling of the set point value 44 makes it possible to adjust the range of variation of the position reference of the clutch abutment to the useful stroke, in order to always use the maximum resolution regardless of the state of wear of the clutch.

  The anticipation means 66 also comprise filtering means, formed for example of a digital transfer function comprising parameter matrices which depend on the nature of the physical process of actuating the clutch by means of the actuator 24. The adjustment means 54 make it possible to modify the parameters of the digital transfer function of the prepositioning or anticipation means 66 as a function of the dynamic response of the actuator, which guarantees an optimum match between the state of wear of the actuator, the values 56 of the disturbing quantities and the desired dynamic response of the actuator 24.

  Similarly, the scaling of the setpoint value 44 by the aforementioned means 58 may be variable as a function of the useful range of variation of the setpoint value 44 and the parameters of a digital filter of the means 58 may be recalculated by the adjustment means 54 as indicated above.

  It is the same with regard to the means 60 for scaling and filtering the measurement 52 of the physical control quantity of the clutch.

  The adapter means 62 may also comprise a digital filter whose parameters are adjusted by the adjustment means 54 as a function of the observed dynamics of the physical operation of the actuator 24 and the values 56 of the disturbing quantities.

  The means 54 for adjusting the parameters of the components of the module 26 use a mathematical model of the actuator 24 and comprise calculation means making it possible to determine all the parameters of this mathematical model. This then makes it possible to calculate the parameters of the components of the module 26 to adapt them perfectly to the dynamics of the actual physical operation of the actuator 24.

  The parameters of the mathematical model of the actuator are determined regularly, for example as a function of the number of clutch and disengage cycles. It is possible to limit the variation of the parameters of this model by calibrated thresholds within bounded domains with calibrated terminals.

  It is also possible, starting from a given type of correcting means in the module 26, to determine beforehand tables of values of the parameters of the components of these correcting means and to select in these tables the values defining correction means which are best adapted to the state or actual behavior of the actuator.

  The values of the state variables that constitute the transfer functions can be initialized to relevant values, calculated and / or determined from formulas and / or tables following the observation of the real dynamic behavior of the actuator from the measured physical quantities.

Claims (8)

  1. A controlled adaptive coupling device between a motor and a gearbox in a motor vehicle, this device comprising a clutch (14), an actuator (24) for controlling the clutch and actuator control means Apparatus (24) comprising a transmission monitoring module (30) embodying drivability management strategies that drive the clutch in torque and / or the engine in speed and / or torque, so as to compensate for the variability of the dynamic behavior of the engine, the gearbox and the rest of the vehicle, a module (28) for controlling the clutch in torque which determines a set value (44) of a physical control quantity of the clutch from a torque setpoint to be transmitted and physical quantities measured on the engine, the gearbox and the rest of the vehicle, and a module (26) for controlling the actuator (24) of the clutch, receiving the set value (44) determined born by the module (28) for controlling the clutch and the signals (34) measured on the engine, the gearbox and the rest of the vehicle and generating a signal (46) for controlling the actuator (24), characterized in that the actuator control module (26) comprises correction means (50, 58, 62, 64, 66, 68) which determine a value of the actuator control signal (46) for canceling, in a minimum of time, the difference between the set value (44) of the physical quantity of the clutch control and a measurement (52) of this physical quantity, and means (54) for adjusting the parameters corrective means as a function of variations in physical physical quantities (56) of the environment such as temperature and / or supply voltage and phenomena such as aging and wear of the actuator and the control of the 'clutch.   2. Device according to claim 1, characterized in that the correction means comprise means (58, 60) for filtering and scaling the set value (44) and the measurement (52) of the magnitude physical control of the clutch, which are connected to a comparator (50) determining the difference between the set value (44) and the measurement (52), and adapter means (62) receiving the difference signal provided by the comparator (50) and modifying it as a function of the output signals of said adjustment means (54).   3. Device according to claim 2, characterized in that the correction means also comprise means (66) for calculating a prepositioning or anticipation of the signal (46) for controlling the actuator (24), these means calculation means (66) being input connected to the aforesaid adjustment means (54) and receiving the setpoint value (44) to generate a pre-positioning or anticipation of control which is added to the output signal of the adapter means (62). ) above.   4. Device according to claim 3, characterized in that the correcting means comprises scaling means (68) receiving as input the signal resulting from the addition of the pre-positioning or anticipation and the signal of output of the adapter means (62) and generating the control signal (46) of the actuator (24).   5. Device according to one of claims 2 to 4, characterized in that the parameters of the filtering means and scaling (58, 60, 68) correction means are defined by the means (54) above.   6. Device according to one of claims 1 to 5, characterized in that the adjustment means (54) receive at the input physical size measurements (56) modifying the dynamic response and the accuracy of the actuator (24) the measurement (52) of the physical control quantity of the clutch and the control signal (46) of the actuator (24).   7. Device according to one of the preceding claims, characterized in that the adjustment means (54) comprise means for calculating the parameters of a mathematical model of the actuator and means for adjusting the parameters of the components of the actuators. corrective means to the actual behavior of the actuator.   8. Device according to claim 7, characterized in that the adjustment means (54) comprise a memory in which are stored tables of values of the parameters of the components of the above corrective means and means for selecting in these tables of the values of parameters defining correction means best adapted to the actual behavior of the actuator (24). 15 20