FR3070946A1 - METHOD FOR CONTROLLING THE MANAGEMENT OF THE MOTOR PROPELLER GROUP OF A MOTOR VEHICLE - Google Patents

Abstract

A method of controlling the power unit of a motor vehicle for performing an automatic maneuver comprising in response to an authorization of an automatic start of operation (E4), a determination (Trait2) and an application (E5, Cons ) a torque setpoint to perform the automatic maneuver without causing discomfort to the passengers. It comprises a preliminary step, in response to an anticipation of a need for automatic maneuvering (E1), calculation (Trait1), taking into account the current speed, a torque value to be applied to a train of drive wheels to achieve a maximum speed compatible with the safety of the vehicle in the automatic operating phase, and a step of using said torque value to be applied to prepare (E2), regardless of the authorization of the start of maneuver the powertrain , to be able to execute a torque setpoint less than or equal to said value to be applied.

Description

METHOD FOR CONTROLLING THE MANAGEMENT OF THE DRIVE GROUP OF A MOTOR VEHICLE [0001] The invention relates to the implementation of automatic maneuvers by a motor vehicle.

The implementation of an automatic operation is based on instructions transmitted to a coordination module of the powertrain, which acts on the various elements thereof, in particular the ignition of the engine and its coupling to the drive wheel train, then the torque transmitted to the drive wheels. The engine can be a heat engine, or an electric motor. It can have a discrete gearbox or a continuous gearbox.

The coordination module of the powertrain acts under the control of an advanced driving assistance supervisor (ADAS system: Advanced driver-assistance Systems). A specific module exists for automatic maneuvers, notably parking.

In certain driving assistance functions, piloting of the coordination of the powertrain in "potential torque" is implemented. This involves defining a torque setpoint in anticipation of an event, to prepare the powertrain to be able to quickly execute a similar setpoint, by prior adjustment of its ignition and coupling states (in particular the selected gear ratio, or the state of closure of the clutches).

Such a function is not yet known in the field of automatic operations. This results in delay times during the implementation of the maneuvers, insufficient longitudinal approval and use of the powertrain which is not made at the best operating points thereof. This is especially a problem when the vehicle is on a slope, or if it is heavily, or conversely very lightly, loaded.

To resolve these difficulties, a method for controlling the management of the motor-propulsion unit of a motor vehicle is proposed for carrying out an automatic maneuver comprising a step, in reaction to an authorization to start a automatic operation, determination and application of a torque setpoint for the powertrain so as to perform the automatic operation without generating discomfort for the passengers.

The method is particular, because it also includes a prior step, in response to anticipation of a need for automatic operation, calculation, taking into account the current speed of the vehicle, a torque value to be applied a train of driving wheels of the vehicle to reach a maximum speed compatible with the safety of the vehicle during the automatic maneuvering phase, and a step of using said torque value to be applied to prepare, independently of the authorization of the start of maneuvering automatic, the powertrain, to be able to execute without delay and with a suitable yield a torque setpoint less than or equal to said torque value to be applied.

According to advantageous features, it is expected that - said step of calculating a torque value to be applied comprises a calculation of an acceleration value capable of being sought to reach said maximum speed, then converting said acceleration value into said torque value to be applied;

- The authorization to start a maneuver is given taking into account the state of ignition of the powertrain and coupling of its elements as assessed by a coordination module of the powertrain ;

- the motor-propulsion couple is prepared by modifying its ignition state and the state of coupling of its elements so as to be ready to execute without delay and with optimized efficiency a torque setpoint equal to said torque value at apply ;

- The automatic maneuver is an automatic parking maneuver;

- the powertrain includes a heat or electric motor, a gearbox with several discrete gear ratios or a continuous variator of gear ratios and a slip clutch or a dog clutch;

- The maximum speed compatible with the safety of the vehicle during the automatic maneuvering phase is adapted according to the state of an automatic maneuvering supervisor.

There is also proposed a device for controlling the management of the powertrain of a motor vehicle for carrying out an automatic maneuver comprising means of, in response to an authorization to start an automatic maneuver, determination and application of a torque setpoint for the powertrain so as to perform the automatic operation without generating discomfort for the passengers.

This device is particular in that it also comprises means of, in reaction to an anticipation of a need for automatic operation, preliminary calculation, taking into account the current speed of the vehicle, of a torque value to be applied to a train of driving wheels of the vehicle to reach a maximum speed compatible with the safety of the vehicle during the automatic maneuvering phase, and means of using said torque value to be applied to prepare, independently of the authorization of the start automatic operation of the powertrain, to be able to execute without delay and with a suitable output a torque setpoint less than or equal to said torque value to be applied.

The invention will be better understood, and other objects, characteristics, details and advantages thereof will appear more clearly in the explanatory description which follows, made with reference to the appended drawings given solely by way of example illustrating a embodiment of the invention and in which:

- Figure 1 is a view of a system according to the prior art;

- Figure 2 is a view of an embodiment of the invention;

- Figure 3 is a view of one aspect of the same embodiment of the invention;

- Figures 4 and 5 are examples of implementation of the invention.

Referring to Figure 1 there is shown a powertrain supervisor 10 (GMP) according to the prior art. It is made up of several modules which communicate with each other.

A first module is the advanced driving assistance supervisor 11. The advanced driving assistance systems, also known by the acronym ADAS are systems developed to automate, or improve, the functions of the vehicle for safety and driving. These systems avoid collisions and accidents by implementing prevention routines to help the driver, or take control of the vehicle when appropriate.

The advanced driving assistance supervisor 11 sends an instruction to the automatic parking instruction coordination module 12. The automatic parking instruction coordination module 12 is a program and / or a controller or processor dedicated to the calculation trajectory and acceleration as well as braking for fully automated parking maneuvers of the vehicle, therefore not or only marginally assisting the intervention of the driver, the latter remaining essentially passive during the maneuver.

The instruction which is sent by the advanced driving assistance supervisor 11 to the automatic parking instruction coordination module 12 is a instruction expressed in torque values CC1. It is an acceleration torque (positive). This setpoint is determined by the supervisor 11 taking into account a maximum acceleration value compatible with passenger comfort, taking into account the speed of the vehicle.

This setpoint is taken care of by a torque value processing sub-module 13. This module 13 is included in the automatic parking setpoint coordination module 12. It delivers a modified torque setpoint CC2. This modified torque setpoint CC2 is transmitted to the powertrain coordination module 14, outside the automatic parking setpoint coordination module 12.

Thus the motor vehicle is equipped with parking assistance, within the supervisor 10 of the powertrain. This parking assistance is embodied by the automatic parking setpoint coordination module 12 which generates setpoints for controlling the torque supplied by the powertrain under the control of the powertrain coordination module 14, but the assistance for the car park is not sufficiently developed to be able to pilot the powertrain coupling states in advance and thus anticipate the coupling time for the maneuver.

It follows from this situation that as the couplings within the powertrain are made only on the basis of a torque setpoint value of the time is lost during the maneuver and the longitudinal approval of the module is not ideal. The couplings concerned are the couplings of the clutches, the gear ratios within the gearbox and the engine start states. It results from the delay in using a simple torque setpoint that the automatic parking setpoint coordination module 12 does not manage to gain access to the entire coupling power of the powertrain and therefore does not optimize the operation of the latter during the maneuver.

In Figure 2 there is shown a supervisor of the powertrain of a motor vehicle according to the invention. The powertrain supervisor is referenced 100. In this supervisor 100 there is an advanced driving assistance module 110, similar to module 11 in FIG. 1. It sends a torque setpoint CC10 to a setpoint coordination module. automatic parking 120. The powertrain coordination module 140 receives a torque setpoint CC20 and also a torque potential setpoint CPC2. Each of these two setpoints CC20 and CPC2 is produced by the automatic parking setpoint coordination module 120.

CC20 torque setpoint is produced by a torque setpoint production module 130, similar to module 13 in Figure 1. Again, this setpoint is determined by the supervisor 110 taking into account a value of maximum acceleration compatible with passenger comfort, taking into account the speed of the vehicle.

The torque potential setpoint CPC2 is itself generated by a torque potential setpoint generation module 131. The two modules 130 and 131 are included in the module for coordinating automatic parking setpoints 120. The module 130 receives the torque setpoint CC10 transmitted by the advanced driving assistance supervisor 110 as an input value.

The CPC2 torque potential setpoint has the function of allowing the powertrain supervisor 140 to anticipate the need for coupling during an automatic parking maneuver, and to prepare the powertrain to receive the torque setpoint. CC20 instantaneous and implement it as quickly as possible with an energy efficiency and in terms of wear of the mechanism which is optimized.

In Figure 3 there is shown the method of calculation and use of the torque potential setpoint CPC2 visible on the right of the figure.

The CPC2 torque potential setpoint is transmitted by the automatic parking setpoint coordination module 120 to the powertrain coordination module 140, as has been mentioned in connection with FIG. 2. The group coordination module powertrain influences the different states of the GMP powertrain. This implies in particular modifications of the coupling between the heat engine and the wheels, by dogs, a gearbox, and / or a slip clutch, the coupling of the electric motor to the wheels, again by means of a dog , a gearbox and / or a sliding clutch, and also the ignition state of the engine.

The GMP powertrain causes the vehicle V to move. This vehicle V moves at a running speed V _c .

The current speed of the vehicle V _c is taken into account by the automatic parking setpoint coordination module 120, first of all through a servo function A. The servo function A uses a reference speed Vcc which is constant, determined for the desired application, here the parking maneuvers, and which typically can be six kilometers per hour. This reference speed Vcc is chosen so that in any case the vehicle does not exceed an admissible speed limit for safety reasons during the automatic maneuver.

The servo A provides an acceleration value, called the AP acceleration potential. The gain of the servo A is determined beforehand so as to allow the powertrain coordination module 140 to have the time necessary to choose and implement the best state of coupling and ignition of the powertrain GM. The servo A, receiving input speed values and providing an acceleration value allows motor vehicles not to exceed the speed limit considered as accepted for the automatic parking maneuver, Vcc.

The gain of this control is determined in advance to allow the powertrain coordination module 140 to have the time necessary to choose the best state of coupling and ignition of the GMP powertrain and to implement this change of state of coupling and ignition as soon as the need appears, without there being an impact in terms of delay in the application of the torque on the drive wheels. Thus, the maneuver can be performed as soon as possible without slowing down due to a change in the states of coupling and ignition of the powertrain difficult to achieve quickly by the system.

It is remarkable in these principles that a speed value is used as a set point V _C c, constant, less than or equal to the speed limit determined for the safety of maneuvers.

The servo A therefore provides a potential acceleration value AP, that is to say that can be requested in the short term, and that the powertrain must therefore be ready to supply without delay. This potential acceleration value AP is transmitted to a transfer function T which converts it into the potential torque setpoint CPC2.

In the foregoing principles, it is specified that the servo function A can be implemented using digital processing of the calculation type followed by filtering, but can also be implemented using the using a predefined map.

In certain variants, the target speed V _C c is determined as a function of the state of the module for coordinating the automatic parking instructions 120.

In Figure 4 there is shown the different stages of the implementation of the invention.

On the abscissa is represented time with the succession of five stages. The ordinates represent the state of the advanced driving assistance supervisor 110, referenced S, the state of the coordination module for automatic parking instructions 120, referenced MCP, and the coordination state of the CGMP powertrain.

During a step E1, a determination Det of the need for automatic operation is carried out and in the event that it is found that there is indeed a need for automatic operation, we go into transition to a step E2. by a torque potential setpoint calculation via a TRAIT 1 mathematical processing implemented in the torque potential setpoint generation module 131.

During step E2 there is an implementation of different modifications in the GMP powertrain with modification of the ignition and coupling states. This implementation is denoted Act for activation of the ignition and coupling states. During this time, the advanced driving assistance supervisor 110 is waiting (step Att, on line S), and is not yet implementing its automatic maneuvering strategy. It is specified that the implementation of the modifications to the ignition and coupling states of the GMP powertrain during the Act stage is carried out using the torque potential setpoint calculated during the Traitl stage. At the end of the implementation of the modifications of the states of ignition and coupling of the powertrain during the Act stage, the powertrain finds itself ready to carry out the maneuver, by a good state of ignition and coupling. This is visualized in the figure by a step E3 and the reference "Ready".

The powertrain being ready, we go during a step E4 to the engagement of the maneuver Man, thanks to the instructions transmitted by the supervisor of advanced driving assistance 110, which are shaped by a mathematical treatment Trait2, within 130.

Authorization for the start of a maneuver Man is given taking into account the ignition state of the GMP power train and coupling of its elements as assessed by the coordination module of the power unit. thruster 140 (CGMP).

During step E5, a calculation of a torque setpoint CC20 is thus implemented by the module for coordinating automatic parking setpoints 120, and from step E5, the GMP powertrain is in able to apply the instructions as a couple without delay and with good performance due to its preparation observed since step E3. The application of the instruction is referenced Cons.

In Figure 5 is shown the evolution over time of the various elements representative of the process. On the abscissa, time is represented with in particular four remarkable instants t0 to t3. On the ordinate, from top to bottom, the state of the advanced driving assistance supervisor 110 is represented, the existence or not of a process for calculating the setpoint in torque potential CPCt, the existence or not a calculation of the torque setpoint CCt, the evolution of the current speed Vcour, the evolution of the torque setpoints CPCt and CCt, and finally the ignition and coupling state of the powertrain.

At time tO, the vehicle moves slowly, accelerating slightly from zero speed. From time t1, the advanced driving assistance supervisor 110 determines that there is a need for maneuvering assistance and then goes into a state 1, from a state previously identified as a state 0. Also from this instant t1, the automatic parking setpoint coordination module 120 begins a calculation of the torque potential setpoint, and an instantaneous torque potential setpoint CPCt begins to be calculated. The vehicle speed Vcour increases while remaining less than a reference speed V _REF which is the maximum speed for safety reasons of the vehicle being maneuvered, as defined by the designer.

From an instant t2 the state of ignition and coupling of the powertrain is reached so that the potential acceleration can be implemented without delay.

The torque potential setpoint CPCt continues to be calculated by the parking maneuvering setpoint coordination module 120 and it increases. The current speed Vcour also increases and remains lower than the reference speed V _REF (Vcc in Figure 3).

Then from an instant t3 the supervisor for advanced driving assistance begins piloting the parking maneuver, switching to a being referenced 2, and this is materialized by the generation by the instructions coordination module automatic parking position 120 of an instantaneous torque setpoint CCt. The instantaneous torque setpoint CCt remains at all times lower than the instantaneous torque potential setpoint CPCt. The current speed of the vehicle Vcour continues to increase slightly while remaining below the reference speed V _REF .

The torque setting CCt is applied to the GMP powertrain which is able to implement it instantly, thanks to its correct preparation sufficiently in advance. The vehicle maneuvers quickly optimally for driver satisfaction. The operating points of the powertrain used are the most adequate, which makes it possible to reduce fuel consumption, and to use the mechanical and electromechanical elements when necessary. This makes it possible to best introduce into the piloting of the automatic maneuver the particular parameters of the situation such as the load of the vehicle (number of passengers, presence of luggage in the trunk, etc.), as well as the state of the surface on which the vehicle is located such as in particular its slope.

Claims (8)

1. Method for controlling the management of the motor-propulsion unit (GMP) of a motor vehicle for carrying out an automatic maneuver comprising a step, in reaction to an authorization to start an automatic maneuver (E4, Man) , determination (Trait2) and application (E5, Cons) of a torque setpoint (CC20) for the powertrain so as to perform the automatic maneuver without generating discomfort for the passengers, characterized in that '' it also includes a preliminary step, in reaction to an anticipation of an automatic maneuvering need (Det, E1), calculation (Traitl), taking into account the current speed (Vc) of the vehicle (V), a torque value (CPC2) to be applied to a drive wheel train of the vehicle to reach a maximum speed (VCC) compatible with the safety of the vehicle during the automatic maneuvering phase, and a step of using said torque value to be applied for prep rer (Act, E2), independently of the authorization of the start of automatic maneuver, the powertrain, to be able to execute without delay and with suitable output a torque setpoint less than or equal to said torque value to apply (CPC2). 2. A method of controlling the management of the power train of a motor vehicle according to claim 1, characterized in that said step of calculating (Traitl) a value of torque to be applied (CPC2) comprises a calculation (A ) an acceleration value (AP) capable of being sought to reach said maximum speed (VCC), then a conversion of said acceleration value (AP) into said value of torque to be applied (CPC2). 3. A method of controlling the management of the power unit of a motor vehicle according to claim 1 or claim 2, characterized in that the authorization for the start of a maneuver (Man) is given taking into account the state of ignition of the powertrain (GMP) and coupling of its elements as assessed by a coordination module of the powertrain (140). 4. Method for controlling the management of the power train of a motor vehicle according to one of claims 1 to 3, characterized in that the drive train (GMP) is prepared by modifying its ignition state and the state of coupling of its elements to be ready to execute without delay and with an optimized yield a torque setpoint equal to said torque value to be applied (CPC2). 5. Method for controlling the management of the motor-propulsion unit of a motor vehicle according to one of claims 1 to 4, characterized in that the automatic maneuver is an automatic parking maneuver. 6. Method for controlling the management of the power train of a motor vehicle according to one of claims 1 to 5, characterized in that the power train comprises a heat or electric engine, a gearbox with several gears discrete or a continuous variator of gear ratios and a slip clutch or a dog clutch. 7. Method for controlling the management of the motor-propulsion unit of a motor vehicle according to one of claims 1 to 6, characterized in that the maximum speed compatible (VCC) with the safety of the vehicle in the automatic maneuvering phase is adapted according to the state of an automatic shunting supervisor. 8. Device for controlling the management of the motor-propulsion unit of a motor vehicle for carrying out an automatic maneuver comprising means (110, 130, 140) of, in reaction to an authorization to start an automatic maneuver , determining and applying a torque setpoint for the powertrain so as to carry out the automatic maneuver without generating discomfort for the passengers, characterized in that it also comprises means (131) of, in reaction to anticipation of an automatic maneuvering need, preliminary calculation, taking into account the current speed of the vehicle, of a torque value to be applied to a train of drive wheels of the vehicle to reach a maximum speed compatible with safety of the vehicle (Vcc) in the automatic maneuvering phase, and of the means of use (140) of said torque value to be applied to prepare, independently of the authorization of the start t automatic operation, the powertrain, to be able to execute without delay and with a suitable output a torque setpoint less than or equal to said torque value to be applied.