FR2926587A1 - Motorized or automatic openable device e.g. motorized sliding lateral door, piloting method for motor vehicle, involves calculating control order of tension to be transmitted to engine using specific formula - Google Patents

Abstract

Method for controlling a motor vehicle opening device, comprising an opening (1) linked to a motor (3) by a cable (4), characterized in that it comprises a step of measuring the speed (x1 <MEASURE> ) of the cable (4), a step of calculating an estimate of state (X) of the opening device, a step of calculating a command by "state observer-feedback" of the voltage (u) to be transmitted to the motor (3) according to the formula where L1 and L2 are control gains and x1 <setpoint> the target speed value sought for the speed of the cable.

Description

REN056FR PJ8437 DA depot 1

The invention relates to a method for controlling a motorized or automatic opening device for a motor vehicle, such as a motorized sliding side door, a motorized tailgate or a retractable roof.

It also relates to an opening device as such implementing the control method and a motor vehicle as such incorporating such an opening device.

The performance of such an opening device is often judged by the uniformity of the movement of said opening concerned, including its speed, its fluidity, and the stability of this movement over time.

However, motorized opening devices are inevitably subject to external disturbances throughout their life cycle. These external disturbances can be caused by variations in normal conditions of use, for example when the vehicle is on a slope or on a slope, by situations of use deviating from normal use, in particular when the mass of the device is modified, for example by adding a luggage rack or a bicycle rack, and by the aging of the mechanical elements of the device.

Because of these external disturbances, the performance of existing opening devices is not satisfactory.

Certain devices of the state of the art use a specific slope sensor, or inclinometer, either with the aim of better modulating the regulation of the speed of the opening device, or to keep the actuator blocked or to brake the opening in the aim to avoid its movement caused by the slope and its own weight. The problem is that the number of sensors is limited and it is therefore difficult with this REN056FR PJ8437 filing DA 2 approach to know the real state of the system and to be able to take into account all the disturbances encountered.

Document US2006 / 0137250 describes a method for controlling a motor vehicle opening on the basis of speed control and regulation by a Derivative Integral Proportional (PID). This method implements slope detection by comparing the measurements of the speed of the motor with the speed of the door. In addition, it uses current measurement to detect anti-pinch. This process does not always give satisfactory results. For example, it does not take into account system failures.

Document FR2895100 proposes a method for controlling a motor vehicle opening from the measurement of the position of the opening by a sensor, estimates of its speed and the disturbances undergone including the slope of the road. These estimates are based on a relatively simple model taking into account the motor voltage control and the position of the opening. These data are then transmitted to a regulation means which slaves the speed to a predefined setpoint. This process is not effective in all configurations. In particular, system failures are not taken into account.

Finally, the existing solutions are unsatisfactory and there is a need for another control solution for a motor vehicle opening device.

More particularly, the object of the invention is to provide a motor vehicle opening device whose movement, mainly defined by its speed and its fluidity, remains stable over time despite external disturbances.

REN056FR PJ8437 DA deposit 3 To this end, the invention provides a method for controlling an opening device of a motor vehicle, comprising an opening linked to a motor by a cable, characterized in that it comprises a step of measuring the speed (x, • measurement) of the cable, a step of calculating a state estimate () of the opening device, a step of calculating a command by observer-status feedback of the voltage (u) to be transmitted to the motor according to the formula u = L1 J (xi • setpoint ù x, measurement) - L2 X where Lt and L2 are control gains and xi • sets the desired setpoint speed value for the cable speed. This method can comprise the measurement of the parameters x, and xi of the position and of the speed of the cable linked to the opening, and the step of calculating an estimate of the state k 'of the device comprises the estimate in real time of the current l flowing through the motor.

It can also include the real-time estimation of the current and of the values x2 and .z2 of the position and the speed of the opening. The step of calculating an estimate of state (X) of the device can include solving the following system of equations: -The electrical equation: u = R x i + Ki, x 9+ L dr -The force at cable level: F = k (x, -x2) + C ~ (xi-x2) 25 -The force balance at the gear level: 20 REN056FR PJ8437 DA deposit 4

xi = - [K, x1ùFxZùCm x8] = _ [L` f (u ù Rxi ù KI, xt) dt ùFxZ ùCn, x B] -The balance of forces at the door: x2 = - (F-Fr + mg sin a) m With the following definitions:

x,, xi, xi: Displacement, speed and acceleration of the cable x2, x2, x2: Displacement, speed and acceleration of the leaf u: Voltage applied to the motor i: Current of the motor R: Resistance of the motor L: Inductance of the motor Kh: Counter-electromotive force constant

e: Angular speed of the motor: Moment of inertia of the motor K,: Torque constant Cm: Friction of the motor Z: Gear ratio F: Cable force

m: Mass of the leaf

a: Slope where the vehicle is located k: Spring constant of the cable C ~: Friction of the cable F,: Resistant forces applied to the opening, for example the reaction of a rail.

REN056EN PJ8437 DA filing 5 And the step of calculating the state estimate (X) of the device can include solving the equation: 0 1 0 0 0 `i0 x. 2 k Cc k C, 0 x2 _ _ z2 mmmm z2 0 0 0 0 1 0 x, + 0 ux 'kZ2 CcZ2 kZ2 CcZ2 + Cn, K, Z x 0 1 _ LJJJJJ 0 0 0 _Kt, _R LZ L ~ Le method can implement a method for detecting a failure of the device, by a first step (E1) of calculating the variation of the current and calculating its final value. It can include a second step (E2) comprising three tests 10 making it possible to determine two situations:

if the current rises instantaneously in saturation, then the method concludes that there is a blockage of the motor;

if the current variation is low and its final value is high, then the method concludes in the presence of an obstacle. 15

In addition, the method for detecting a failure can implement a third step (E3) if the final value is low (of the same order of magnitude as during nominal operation) and the slope is normal, 20 - if the final value is of the order of 1.2 = C 'u, then the Ke K, + RC, motor no longer holds the cable; REN056FR PJ8437 DA deposit 6 -if the device is in an acceleration phase, the current decreases slightly and the final current value is low, then the cable no longer holds the door; - if the device is in a deceleration phase, the current 5 increases slightly and the final value of the current is low, then the cable no longer holds the door.

The invention also relates to an opening device for a motor vehicle, comprising an opening device connected to an engine by a cable, a means 10 for measuring the speed (xi measurement) of the cable, at least one computer suitable for use. by at least one computer program for the calculation of the state estimate (X) of the opening device, means for the calculation of a command by observer or state feedback of the voltage (u) to be transmitted to the motor according to the formula u = L1 f (x1 setpoint ù xl measurement) L L2 X, 15 where LI and L2 are control gains and xi sets the desired setpoint speed value for the cable speed.

The computer can implement a program for estimating the current (i) of the motor on the basis of the measured values of position and speed of the cable, and comprises a logic unit capable of implementing the method of detecting failure of the device. opening from the real-time estimate of the variation of the current and the calculation of its final value according to a method as described above.

The invention also relates to a motor vehicle comprising an opening device as described above.

REN056FR PJ8437 DA filing 7 These objects, characteristics and advantages of the present invention will be explained in detail in the following description of a particular embodiment made without limitation in relation to the accompanying figures, among which: FIG. 1 represents an exploded perspective view of an opening device according to one embodiment of the invention; FIG. 2 represents a simplified electronic diagram of the opening device according to the embodiment of the invention; FIGS. 3 and 4 represent performance curves of the opening device according to the embodiment of the invention respectively under nominal conditions and under aging conditions; FIGS. 5 to 7 represent curves of the current as a function of time of the opening device according to different failure situations according to a variant of the embodiment of the invention; FIG. 8 represents a method for diagnosing faults of the opening device according to the variant of the embodiment of the invention; FIG. 9 represents a simplified electronic diagram of the opening device according to the variant of the embodiment of the invention.

The invention will be illustrated by way of example in the context of the opening of a motorized sliding side door of a motor vehicle. It could naturally be applied to any motorized opening device of a motor vehicle, the opening then being able to be something other than a side door.

FIG. 1 illustrates the mechanical elements 20 of a motorized sliding side door of a motor vehicle, which comprises a motor vehicle door 1, connected to the motor vehicle by upper and lower rails, not shown, and by an intermediate rail 2.

REN056FR PJ8437 DA deposit 8 This door 1 is connected to a motor 3 by a cable 4, capable of transmitting the force of the motor 3 to the door 1, after passing through a gear 5, in order to drive the sliding door 1 in translation in one way or the other. The device further comprises a computer and / or electronic components, sensors for measuring the position and speed of the cable, not shown.

The computer uses a model of the operation of the opening device by the following equations: Electrical equation: u = Rxi + Kh x 8 + L di Force at the level of the cable: F = k (x, -x2) + Ce. (X, ùx2 ) Balance of forces at the gear level: 15 xi = j [K, xIùFxZùC ,,, x0] = - [L 'f (uùRxiùKh xO) dtùFxZùC, n x0] Balance of forces at the door: x2 = ù (F -Fr + mgsina) m With the following definitions:. x ~, xi, x,: Displacement, speed and acceleration of the cable. x2, x2, x2: Movement, speed and acceleration of the door

u: Voltage applied to the motor i: Motor current

25 R: Motor resistance

L: Motor inductance 20 REN056FR PJ8437 DA deposit 9 Kh: Counter-electromotive force constant 9: Motor angular speed: Motor moment of inertia K,: Torque constant Cm: Motor friction Z: Gear ratio F : Cable force m: Door mass a: Slope where the vehicle is located k: Cable spring constant Cc: Cable friction: Resisting forces applied to the door (ex: reaction of the rail) These equations can be expressed as a status representation: 0 1 0 0 0 ~ x2 k _Cc k CL 0 ixi 2 0 Z2 mmmm Z2 0 x, = 0 0 0 1 0 x, + O u kZ2 CcZ2 kZ2 Cc.Z2 + Cm K, ZX '0 1 JJJJJ Ii L 0 0 0 ùKh ùR LZ L i REN056FR PJ8437 DA deposit 10 (0 0 1 0 0 "~ 0 0 0 1 .Y = Based on the measurement of parameters x, and xi and the solving the previous equations, the computer can reconstruct the state of the system at any time, and therefore reconstruct the unmeasured states of the system (1, x2 and z2), in real time. reversion of the cable speed with respect to a speed setpoint as is usual.

To do this, it calculates the error resulting from the difference between the actual value and the setpoint and controls the motor voltage accordingly. However, according to the embodiment of the invention, the computer comprises a regulator for implementing this slaving based on a command by observer ù state feedback, and not by an Integral Proportional (PI) as in the state. of technique.

For this, the regulator determines the voltage command applied to the motor is calculated by the following formula, on the basis of the electronic device shown in figure 2: u = LI 5 (xI • setpoint ù x, • measurement) ù L2 X where î represents the states of the system reconstructed by the observer and Lt and L2 control gains.

REN056FR PJ8437 DA filing 11 Thus, as shown in FIG. 2, the opening device according to the embodiment of the invention therefore comprises a mechanical system 20 to be controlled, on the basis of a speed instruction transmitted by a element 21. At any time, the mechanical system 20 transmits to the rest of the device via two outputs 22, 23 respectively the value of the measurements of the position of the door xi and of its speed xi. The value of this speed 22 as well as the value of the voltage u 24 transmitted to the motor are transmitted to the observer 25. The latter calculates the estimates of the state parameters of the device, 1, x2 and, and transmits them at output 26 to the device for regulating the controlled mechanical system, after multiplication by a gain L2. This regulation device further comprises an integrator 27 and a gain 28. This device thus makes it possible to determine the voltage u to be transmitted at the input 24 for controlling the motor 3 of the mechanical system 20.

This solution has the advantage of improving the robustness of the speed control of the opening device and of processing this device in real time.

To illustrate these advantages, FIGS. 3 and 4 represent the speeds of the door of the opening device obtained as a function of time for respectively nominal conditions of the device and for a situation where the counter-electromotive force constant Kh of the device is modified so to represent 0.7 times its face value. This modification makes it possible to illustrate a possible situation occurring during the aging of the device. Each figure includes three curves 7, 8, 9 representing respectively the values as a function of time of the setpoint speed, of the real speed obtained by a PI type regulation, and of the real speed obtained by an observer type regulation û feedback state. We realize that in the two REN056FR PJ8437 DA 12 situations, curve 9 representing the implemented solution closely follows the setpoint, much better than curve 8. This difference is much more convincing in the case of a situation far from nominal conditions, as shown in figure 4.

In addition to taking into account the aging and the dispersion of the components as illustrated above, the device can implement, according to an interesting variant embodiment, steps for detecting its possible own failure. For this, the computer estimates the current i on the basis of the equations detailed above and can determine various failures from this estimate.

In fact, the preceding system of equations makes it possible to take account of certain following particular situations: • B = 0 and Z = 0, the motor is blocked (case 1); • Z = 0, this is the loss of connection between the motor and the cable (case 2), 20 • k = 0 and C, = 0, it is the loss of connection between the cable and the door (case 3).

For each of these three cases, the evolution of the current is different. For the third case, the evolution of the current is also different depending on the location of the profile where the failure is located, among the following three zones: the acceleration phase at the time of the initial setting in motion; • the stabilized phase when the speed setpoint is constant; 10 REN056EN PJ8437 DA deposit 13 • the deceleration phase towards the end of the movement.

Figures 5, 6 and 7 give the current curves 11, 12, 13 as a function of time according to the different particular situations specified above and in the three profile zones defined above, respectively of acceleration, stabilization and of deceleration. In each figure, these curves are compared with the normal operating curve 10.

Finally, the method for controlling the opening device can include a fault detection method, illustrated schematically in FIG. 8, implemented by a logic unit, for the different cases explained above. This method therefore comprises a first step E1 which consists in calculating the variation of the current, ie the slope of the current, and its final value, during the movement SO of the opening device.

Then, in a second step E2, the method performs the following three tests, respectively Ti, T2, T3, in order to obtain respectively three different situations, two determined situations S1, S2 and an indeterminate situation: if the current instantly rises in saturation (T1) (for example Imax = 30A for the motor considered), which is for example detected by the following conditions: i (t) û i (t -1)> I2 x and Final current I, nax, then the process concludes that there is an engine blockage (SI); if the current variation is low and its final value is high (T2), which is for example detected by the following conditions: i (t) û i (t -1) <I x and Final current z- Imax ' then the method concludes in the presence of an obstacle (S2); REN056EN PJ8437 DA deposit 14 if the final value is low (of the same order of magnitude as during nominal operation) and the slope is normal (T3), i.e. the current increases moderately (i ( t) - i (t -1) <I2 X), then additional tests are carried out in a third step E3, the situation still remaining undetermined.

The third step E3 makes it possible to detect any mechanical breakdowns of the device. It implements the following three complementary tests T4, T5, T6, to lead respectively to three situations S3, S4, S5: - if the final value, calculated from the dynamic equations, is of the order of 1 .. 2 = Cl u (T4) (approximately 7.5A depending on the K1, K, + RC, execution mode), then the motor no longer holds the cable (S3); 15 - if the device is in an acceleration phase, that the current decreases slightly (i (t) -i (t -1) <-2A depending on the mode of execution) and that the final value of the current is low ( Final current <Imax) (T5) then the cable no longer holds the gate (S4); - if the device is in a deceleration phase, that the current 20 increases slightly (i (t) -i (t -1)> 2A depending on the mode of execution) and that the final value of the current is low (Final current <Imax) (T6) then the cable no longer holds the door (S5 = S4).

FIG. 9 schematically illustrates the complete opening device according to this variant embodiment. It includes the components already explained in relation to FIG. 2, and further comprises a logic unit 29, which can be software for a computer, possibly the same as that REN056FR PJ8437 DA deposit 15 hosting the observer 25 already described, and / or a set of electronic hardware components, to implement steps E1 to E3 of the failure detection method described above. At the output, it makes it possible to inform the rest of the device and the motor vehicle of fault situations S1 to S4, by means of communication not shown.

The method for detecting a failure of the opening device has been advantageously implemented with the calculation of an estimate of the current according to the specified equations. As a variant, a similar method could be implemented with the measurement of this current by a sensor.

On the other hand, the invention has been illustrated on the basis of a particular advantageous model of the device. However, it could be implemented on the basis of another model, simplified or specified equations ...

In addition, the computer may be a simple microprocessor or several microprocessors, implementing the various calculation steps by a method executed by a computer program.

Claims (10)

Claims 1. A method of controlling a motor vehicle opening device, comprising an opening (1) linked to a motor (3) by a cable (4), characterized in that it comprises a step of measuring the speed (x , measurement) of the cable (4), a step of calculating an estimate of state (X) of the opening device, a step of calculating a command by observer ù status feedback of the voltage (u) to be transmitted to the motor (3) according to the formula u = L1 J () cl setpoint ù xi measurement) ù L2 where LI and L2 are control gains and x, sets the desired setpoint speed value for the cable speed. 2. A method of controlling a motor vehicle opening device according to claim 1, characterized in that it comprises measuring the parameters xi and xi of the position and speed of the cable (4) linked to the opening ( 1), and in that the step of calculating an estimate of the state of the device comprises the real-time estimate of the current i flowing through the motor. 3. A method of controlling a motor vehicle opening device according to claim 1 or 2, characterized in that it also comprises the real-time estimation of the current and of the values x2 and z2 of the position and the speed of the. 'opening (1). 4. Method for controlling a motor vehicle opening device according to one of the preceding claims, characterized in that the step REN056FR PJ8437 DA filing 17 for calculating an estimate of state (X) of the device comprises the resolution of the following system of equations: -The electrical equation: u = Rxi + Kh x 9+ L di dt - The force at the level of the cable: F = k (x, -x2) + Cc (x, -x2) 5 -The balance of forces at the gear level: xi = J [K, xIùFxZxe] = - [L f (u-Rxi-Kh xe) dt-FxZ-C ,,, xB] - The balance of forces at door level: x2 = 1 (F- F, + mgsina) m With the following definitions: 10, x,,: Displacement, speed and acceleration of the cable x2, x2, x2: Displacement, speed and acceleration of the leaf u: Voltage applied to the motor i: Motor current R: Motor resistance 15 L: Motor inductance Kh: Counter-electromotive force constant e: Motor angular speed: Motor moment of inertia K,: Torque constant 20 Cm: Motor friction Z: Gear ratio F: Cable force m: Mass of the leaf a: Slope where the vehicle is REN056FR PJ8437 DA deposit 18 k: Cable spring constant C ~: Cable friction F,: Resistant forces applied to the opening, for example the reaction of a rail, and in that the step of calculating the state estimate (X) of the device comprises solving the equation: 0 1 0 0 0 kk 0 mmmm 0 0 0 1 0 kZ2 C ~ Z2 _ kZ2 C ~ Z2 + C ,,, K, ZJJJJJ 0 0 0 KI, R LZ L i 10 5. Method for controlling a motor vehicle opening device according to one of the preceding claims, characterized in that it implements a method for detecting a failure of the device, by a first step (El) of calculating the variation of the current and calculating its final value. 15 6. Method for controlling a motor vehicle opening device according to the preceding claim, characterized in that the method for detecting a failure comprises a second step (E2) comprising three tests (T1, T2, T3) making it possible to determine two 20 situations (SI, S2): if the current rises instantaneously in saturation (T1), then the method concludes that there is a blockage of the motor (S1); 5REN056EN PJ8437 DA 19 filing if the current variation is low and that its final value is high (T2), then the method concludes in the presence of an obstacle (S2). 7. A method of controlling a motor vehicle opening device according to the preceding claim, characterized in that the method of detecting a failure implements a third step (E3) if the final value is low (of the same order of magnitude only during nominal operation) and that the slope is normal (T3), - if the final value is of the order of Icasz = C 'u (T4), then the Kh K, + RC, motor does not hold plus the cable (S3); - if the device is in an acceleration phase, the current decreases slightly and the final current value is low (T5), then the cable no longer holds the door (S4); -if the device is in a deceleration phase, the current increases slightly and the final value of the current is low (T6), then the cable no longer holds the door (S5 = S4). 8. Motor vehicle opening device, characterized in that it comprises an opening device (1) connected to a motor (3) by a cable (4), a means for measuring the speed (xt measurement) of the cable, at the at least one computer capable of implementing by at least one computer program the calculation of the state estimate (X) of the opening device, means (21, 22, 26, 27, 28) for the calculation of 'a command by observer to return the state of the voltage (u) to be transmitted to the motor (3) according to the formula u = L1 f (xi ^ setpoint ù xi ^ measure) ù L2, where Lt and L2 are control gains and xi sets the desired setpoint speed value for the cable speed (4) REN056EN PJ8437 filing DA 20 9. Motor vehicle opening device according to the preceding claim, characterized in that the computer implements a program for estimating the current (i) of the motor from the measured values of position and speed of the cable (4), and comprises a logic unit (29) capable of implementing the method for detecting failure of the opening device from the real-time estimate of the variation of the current and the calculation of its final value according to a method according to one of the claims 5 to 7. 10. Motor vehicle characterized in that it comprises an opening device according to one of claims 8 or 9.15