CONTROL OF THE USE OF DRIVER ASSISTANCE FUNCTION(S) IN A VEHICLE WITH AT LEAST PARTIALLY ELECTRIC POWERTRAIN

Abstract

A control method is implemented in a land vehicle comprising an electric drive unit controlled by a control device having forward and reverse positions associated respectively with opposite theoretical directions of vehicle travel, and at least one driver assistance function for setting a speed limit. This method includes a step (10-30) in which, when the driver assistance function is used and the vehicle has an actual direction of travel opposite to the theoretical direction of travel associated with the current position of the control device, the driver assistance function is inhibited. Figure 3

Description

Title of the invention: CONTROL OF THE USE OF DRIVER ASSISTANCE FUNCTION(S) IN A VEHICLE WITH AT LEAST PARTIALLY ELECTRIC POWERTRAIN Technical field of the invention

[0001] The invention relates to vehicles comprising an all-electric or hybrid powertrain (or PMT) and at least one driver assistance function enabling the establishment of a speed limit, and more specifically the control of the use of such a driver assistance function. State of the art

[0002] Certain vehicles, possibly of the automobile type, include an all-electric or hybrid (thermal and electric) powertrain (or PWM) controlled by a control device having forward and reverse positions associated respectively with opposite theoretical directions of travel (forward and backward). This control device is generally a gear lever operated by the vehicle driver, which allows the PWM's gearbox to be configured, to which the PWM's electric drive unit can be coupled by a coupling device.

[0003] In general, due to the technology of the electric drive unit (and unlike the internal combustion engine), it is not necessary to include in the powertrain a reduction gear that reverses the direction of rotation between the electric drive unit and the drive wheels. In an all-electric driving phase, the forward movement of the vehicle is ensured by a so-called positive torque supplied by the electric drive unit, while the reverse movement of the vehicle can be ensured by a so-called negative torque that induces a negative speed of the electric drive unit or by a mechanical torque reverser.

[0004] The land vehicles described above may include at least one driver assistance function (or ADAS (“Advanced Driver Assistance System”)) that allows a speed limit to be set, such as a speed limiter or a speed restrictor function. This type of driver assistance function interacts with the powertrain for speed management and / or longitudinal acceleration purposes by imposing a maximum torque on it.

[0005] Historically, the driver assistance functions mentioned above have a powertrain control convention according to which a positive torque is a torque that accelerates the vehicle regardless of its actual direction of travel, while a negative torque is a torque that brakes the vehicle regardless of its direction of travel. However, the powertrain control unit, which determines the torque commands for the control units driving each powertrain motor and the gearbox, does not use the same control convention as the aforementioned driver assistance systems (they often use different torque reference frames). Indeed, the powertrain control unit takes into account the vehicle's actual direction of travel, which can sometimes be opposite to the theoretical direction of travel associated with the current position of the control device.

[0006] As long as the actual direction of movement of the vehicle is identical to the theoretical direction of movement in progress, there is no conflict between the powertrain control unit and a driving assistance function allowing the establishment of a speed limit.

[0007] Conversely, when the vehicle's actual direction of travel is opposite to its theoretical direction of travel, a conflict arises between the powertrain control unit and the driver assistance function responsible for setting a speed limit. This conflict can occur, in particular, when the control device is in the drive position while the vehicle is facing uphill and is reversing due to gravity, or when the control device is in the reverse position while the vehicle is facing downhill and is moving forward (downhill) due to gravity. Such conflicts can cause abnormal vehicle movements and / or reactions that may surprise the driver and / or be potentially dangerous for the vehicle and / or its surroundings.

[0008] The invention therefore aims in particular to improve the situation. Presentation of the invention

[0009] In particular, it proposes for this purpose a control method intended to be implemented in a vehicle comprising, on the one hand, a powertrain with an electric motor and controlled by a control device having forward and reverse positions associated respectively with opposite theoretical directions of movement of the vehicle, and, on the other hand, at least one driving assistance function allowing a speed limit to be established.

[0010] This control method is characterized by the fact that it includes a step in which, when the (each) driving assistance function is used and the vehicle has an effective direction of travel opposite to the theoretical direction of travel associated with the current position of the control device, this (each) driving assistance function is inhibited.

[0011] This temporary inhibition, when the actual direction of movement is opposite to the theoretical direction of movement in progress, allows that there is no longer a conflict between the powertrain monitoring computer and the (each) driving assistance function, and therefore that there is no longer a risk of abnormal movement and / or abnormal reaction of the vehicle.

[0012] The control method according to the invention may include other features which may be taken separately or in combination, and in particular:

[0013] - in a first embodiment, in its step, one can inhibit the (each) driver assistance function by temporarily prohibiting its use;

[0014] - in a second embodiment, in its step, one can inhibit the (each) driver assistance function by imposing a chosen speed limit on the vehicle;

[0015] - in this second embodiment, in its step, the chosen limiting speed can be between 190 km / h and 300 km / h;

[0016] - in the presence of the last sub-option, in its step, the chosen speed limit can to be equal to 255 km / h.

[0017] The invention also proposes a computer program product comprising a set of instructions which, when executed by processing means, is suitable for implementing a control method of the type presented above, in a vehicle comprising, on the one hand, a powertrain with an electric motor and controlled by a control device having forward and reverse positions associated respectively with opposite theoretical directions of movement of the vehicle, and, on the other hand, at least one driving assistance function allowing the establishment of a speed limit, to control the use of the (each) driving assistance function.

[0018] The invention also proposes a control device intended to equip a vehicle comprising, on the one hand, a powertrain with an electric motor and controlled by a control device having forward and reverse positions associated respectively with opposite theoretical directions of movement of the vehicle, and, on the other hand, at least one driving assistance function allowing a speed limit to be established.

[0019] This control device is characterized by the fact that it comprises at least one processor and at least one memory arranged to perform the operations consisting, when the (each) driving assistance function is used and the vehicle has an effective direction of movement opposite to the theoretical direction of movement associated with the current position of the control device, of triggering an inhibition of this (each) driving assistance function.

[0020] The invention also proposes a vehicle, possibly of the automobile type, comprising, on the one hand, a powertrain with an electric motor and controlled by a control device having forward and reverse positions associated respectively with opposite theoretical directions of movement of the vehicle, and at least one driving assistance function allowing a speed limit to be set, and, on the other hand, a control device of the type presented above.

[0021] For example, the powertrain may also include a thermal engine. Brief description of the figures

[0022] Other features and advantages of the invention will become apparent from an examination of the detailed description below, and the accompanying drawings, in which:

[0023] [Fig. 1] schematically and functionally illustrates an example of the realization of a land vehicle comprising a control device according to the invention and a hybrid powertrain transmission chain and associated with a supervisory computer,

[0024] [Fig.2] schematically and functionally illustrates an example of the realization of a supervisory calculator including an example of an embodiment of a control device according to the invention, and

[0025] [Fig.3] schematically illustrates an example of an algorithm implementing an control method according to the invention. Detailed description of the invention

[0026] The invention aims in particular to propose a control method, and an associated DC3 control device, intended to allow control of the use of at least one driving assistance function enabling the establishment of a speed limit vl in a land vehicle V comprising a powertrain (or GMP) that is all-electric or hybrid (thermal and electric).

[0027] In what follows, the land vehicle V is considered, by way of non-limiting example, to be a motor vehicle. This is, for example, a car, as illustrated in [Fig. 1]. However, the invention is not limited to this type of land vehicle. It relates to any type of land vehicle comprising a fully electric or hybrid (thermal and electric) powertrain and having at least one driver assistance system (or ADAS) enabling the setting of a speed limit. Thus, it relates in particular to commercial vehicles, motorhomes, minibuses, coaches, trucks, motorcycles, road maintenance vehicles, construction equipment, agricultural vehicles, recreational vehicles (snowmobiles, go-karts), and tracked vehicles, for example.

[0028] Furthermore, in what follows, by way of non-limiting example, the powertrain is considered to be hybrid (thermal and electric). However, the invention is not limited to this type of powertrain. It also relates to all-electric powertrains, and therefore includes at at least one electric drive unit associated with at least one rechargeable battery (called the main or traction battery) or a fuel cell (for example, a hydrogen fuel cell). Generally speaking, the invention relates to all powertrains equipped with at least one electric drive / generator.

[0029] A (land) vehicle V comprising a hybrid GMP transmission chain (and therefore in particular a thermal drive machine MMT and an electric drive machine MME), a CS supervision computer, a rechargeable BA battery, and a DC3 control device according to the invention, is schematically represented in [Fig.1].

[0030] As illustrated, the transmission chain also includes, here, a drive shaft AM, a first coupling device DC1, a second coupling device DC2, a gearbox BV associated with a control device DC4, and a transmission shaft AT.

[0031] The operation of the transmission chain (and therefore of the GMP) is supervised by a CS supervision computer.

[0032] The MMT internal combustion engine comprises a crankshaft (not shown) which is fixedly attached to the drive shaft AM in order to rotate the latter (AM). This MMT is designed to operate in a first operating mode to provide a first torque, as instructed by the CS supervisory control unit. Furthermore, it (MMT) is designed to be coupled to the BV gearbox, which has a second operating mode as input, via at least the first coupling device DC1. This device (DC1) is designed to deliver a second torque from the first torque, specifically for at least one set T1 of drive wheels, when it is in its coupled position and therefore when it couples the MMT internal combustion engine to the BV gearbox. This second torque is defined by a clutch torque setpoint which is determined by the CS supervisory control unit.

[0033] It should be noted that the operation of the MMT thermal drive machine is controlled either by a speed setpoint when the first coupling device DC1 is sliding, or by a torque setpoint when the first coupling device DC1 is in its coupling position (or closed), the speed or torque setpoint being determined by the CS supervisory computer.

[0034] For example, the first coupling device DC1 can be a hydraulic circuit clutch. But it could be of another type.

[0035] Also, for example, the Tl axle can be located in the front PVV section of the vehicle V. It is preferably, and as illustrated, coupled to the AT driveshaft via a differential (here, the front one) DV. But in a variant, this Tl axle could be the one referenced as T2, which is located in the rear PRV section of the vehicle V.

[0036] The electric drive machine MME is, here, installed between the first coupling device DC1 and the gearbox BV, and is suitable for providing a third torque, defined by a torque setpoint determined by the supervisory computer CS.

[0037] When the first coupling device DC1 has been placed in its coupled (or fully closed) state and the thermal drive machine MMT is running (and therefore at a first non-zero speed to provide the first torque), the first coupling device DC1 delivers a second torque which is added to a possible third torque provided, upstream of the gearbox BV, by the electric drive machine MME when it is supplied with electrical energy by the rechargeable battery B A. When the first coupling device DC1 has been placed in its decoupled (or fully open) state, only the electric drive machine MME can provide a third torque upstream of the gearbox BV in a purely electric driving phase.

[0038] The electric drive unit MME is also arranged, during a charging phase, to recharge the associated rechargeable battery BA in the presence of the second torque. More precisely, during a charging phase, it (MME) is capable of producing, from the second torque (from the first coupling device DC1), a third torque with a negative value opposite to that of the first torque (supplied by the internal combustion engine MMT) to recharge the associated rechargeable battery BA. It should be noted that it (MME) can also recharge the rechargeable battery BA by producing a negative torque during a regenerative braking phase.

[0039] For example, the rechargeable battery BA can be of the cellular type. In this case, it comprises electrical energy storage cells, possibly electrochemical (such as lithium-ion (or Li-ion) or Ni-MH or Ni-Cd cells). Also, for example, this rechargeable battery BA can be of the 450 V type. But this is not mandatory. Indeed, it could alternatively be of the 48 V or 600 V type, for example.

[0040] The gearbox BV is automated and configurable by the associated control device DC4. This control device DC4 has, in particular, a forward position associated with a theoretical forward direction sdtl of vehicle V and a reverse position associated with a theoretical backward direction sdt2 of vehicle V. These two theoretical directions of travel sdtj (j = 1 or 2) are therefore opposite to each other. For example, the control device DC4 can be a gear lever that is operated by the driver of vehicle V.

[0041] Also, for example, the gearbox can be of the so-called "dual-clutch (or DCT)" type. But the invention is not limited to this type of gearbox.

[0042] It should be noted that in the example illustrated, but not limited to, in [Fig. 1], the transmission chain also includes a second coupling device DC2 installed downstream of the first coupling device DC1 and the electric drive machine MME and upstream of the gearbox BV. However, this is not mandatory.

[0043] It should also be noted that in the example illustrated, but not limited to, in [Fig. 1], the first coupling device DC1, the second coupling device DC2, the electric drive machine MME and the gearbox BV are part of a gearbox assembly EBV. However, this is not mandatory.

[0044] The vehicle V also has at least one driver assistance function (fac) that allows a speed limit to be set. For example, each driver assistance function (fac) can be selected from a speed limitation function and a speed restriction function. It should be noted that each driver assistance function (fac) can be implemented by at least one on-board computer in the vehicle V, as well as at least one electronic component or piece of equipment.

[0045] As mentioned above, the invention proposes in particular a control method intended to allow control of the use of at least one driving assistance function fac allowing to establish a speed limit vl, for example chosen (or selected) by the driver (or user) of the vehicle V.

[0046] This (control) method can be implemented at least partially by the DC3 control device (illustrated at least partially in Figures 1 and 2), which for this purpose comprises at least one PR1 processor, for example a digital signal processor (or DSP), and at least one MD memory. This DC3 control device can therefore be implemented as a combination of electrical or electronic circuits or components (or "hardware") and software modules (or "software"). For example, it could be a microcontroller.

[0047] The MD memory is random access memory (RAM) to store instructions for the implementation by the PR1 processor of at least part of the control process. The PR1 processor may comprise integrated (or printed) circuits, or several integrated (or printed) circuits connected by wired or wireless connections. An integrated (or printed) circuit is defined as any type of device capable of performing at least one electrical or electronic operation.

[0048] In the example illustrated, but not limited to, in Figures 1 and 2, the DC3 control device is part of the CS supervisory computer. However, this is not mandatory. Indeed, the DC3 control device could comprise its own dedicated computer, which is then coupled to the CS supervisory computer, or it could be part of another computer embedded in the vehicle V and performing at least one other function, for example.

[0049] As illustrated non-limitingly in [Fig.3], the (control) method according to the invention includes a step 10-30 which is implemented each time at least one driver assistance function fac (allowing a speed limit vl to be established) is used (or activated) in the vehicle V.

[0050] Step 10-30 of the method includes a substep 30 in which, when a driving assistance function fac (allowing a speed limit vl to be established) is used and the vehicle V has an effective direction of travel sde which is opposite to the theoretical direction of travel sdtj associated with the current position of the control device DC4, this driving assistance function fac is inhibited (the control device DC3 triggers the inhibition of)

[0051] Thanks to this temporary inhibition, when the actual direction of movement sde is opposite to the theoretical direction of movement sdtj in progress, there is no longer a risk of conflict between the supervisory computer CS and the (each) driving assistance function fac, and therefore there is no longer a risk of abnormal movement and / or abnormal reaction of the vehicle V, which improves driving pleasure and strengthens the safety of the passengers of the vehicle V and of living beings and objects present in the environment of the latter (V).

[0052] For example, and as illustrated non-limitingly in [Fig. 3], step 10-30 of the method may include a substep 10 in which the control device DC3 determines from a computer on board the vehicle V the actual direction of travel sde of the latter (V) and the theoretical direction of travel sdtj which is associated with the current position of the control device DC4. Then, in a substep 20 of step 10-30, the control device DC3 determines whether this determined actual direction of travel sde is opposite to the determined theoretical direction of travel sdtj. If not, the control device DC3 performs substep 10 again. If so, the control device DC3 performs substep 30 in order to inhibit each driver assistance function.It will be understood that as soon as the actual direction of movement sde determined becomes identical to the theoretical direction of movement sdtj determined, we (the DC3 control device) disinhibit the (each) driving assistance function fac previously inhibited.

[0053] At least two embodiments can be envisaged for carrying out the inhibition.

[0054] In a first embodiment, in substep 30, each driver assistance function fac can be inhibited (the DC3 control device can trigger the inhibition of) by temporarily prohibiting its use. It will be understood that in this first embodiment, as soon as the actual direction of travel sde determined becomes identical to the theoretical direction of travel sdtj determined, one (the DC3 control device) re-authorizes the use (or activation) of (each) driver assistance function fac.

[0055] In a second embodiment, in substep 30, each driver assistance function fac can be inhibited (the DC3 control device can trigger the inhibition of) by imposing a chosen speed limit vie on the latter (fac). It will be understood that this chosen speed limit vie is very high compared to the current speed of the vehicle V, and also preferably higher than the maximum speed that the vehicle V can achieve, to avoid any risk that the latter (V) might reach the speed limit vl previously chosen for the driver assistance function fac in question.

[0056] For example, the chosen speed limit for life can be between 190 km / h and 300 km / h. This depends, for example, on the power of the vehicle's engine and / or applicable regulations. As an illustrative example, the chosen speed limit for life could be 255 km / h.

[0057] In this second embodiment, as soon as the actual direction of movement sde determined becomes identical to the theoretical direction of movement sdtj determined, the (control device DC3) re-authorizes the use of the limit speed vl previously in force before the inhibition by using the chosen limit speed vie.

[0058] The invention offers several advantages, including:

[0059] - an improvement in driving comfort,

[0060] - robustness of the control strategies for driver assistance functions allowing for the establishment of a speed limit for vehicles,

[0061] - the possibility of having strategies for controlling the driver assistance functions allowing the establishment of a speed limit vl which are identical regardless of the type of GMP (purely thermal, hybrid, or purely electric) and regardless of the way in which reverse gear is achieved (reversal of the gear ratio or reversal of the direction of rotation of the electric drive machine MME).

[0062] - the end of the occurrence of a fault inducing an increase in speed of the vehicle V,

[0063] - improved readability of strategies by users of vehicle V.

[0064] It should also be noted, as illustrated but not limited to [Fig. 2], that the CS supervisory computer (or the DC3 control device computer) may also include a mass memory MM1, in particular for storing the actual direction of travel sde and the current theoretical direction of travel sdtj, as well as any intermediate data involved in all its calculations and processing. Furthermore, this CS supervisory computer (or the DC3 control device computer) may also include an IE input interface for receiving at least the actual direction of travel sde and the current theoretical direction of travel sdtj, for use in calculations or processing, possibly after having shaped and / or demodulated and / or amplified, in a manner known per se, by means of a PR2 digital signal processor. In addition, this CS supervisory computer (or the DC3 control device computer) may also include an IS output interface, in particular to deliver each inhibition message of a driving assistance function fac allowing the establishment of a speed limit vl and each end of inhibition message of a driving assistance function fac allowing the establishment of a speed limit vl.

[0065] It will also be noted that the invention also proposes a computer program product (or computer program) comprising a set of instructions which, when executed by processing means of the type of electronic circuits (or hardware), such as for example the PR1 processor, is suitable for implementing the control method described above to control the use of the (each) driving assistance function fac allowing to establish a speed limit vl in the vehicle V.

Claims

Demands

1. A control method for a land vehicle (V) comprising i) a powertrain with an electric motor (EM) and controlled by a control device (DC4) having forward and reverse positions associated respectively with opposite theoretical directions of travel of said vehicle (V), and ii) at least one driver assistance function enabling the establishment of a speed limit, characterized in that it comprises a step (10-30) in which, when said driver assistance function is used and said vehicle (V) has an actual direction of travel opposite to the theoretical direction of travel associated with the current position of said control device (DC4), said driver assistance function is inhibited by imposing on the latter a chosen speed limit, said chosen speed limit being between 190 km / h and 300 km / h.

2. n. Method according to claim 1, characterized in that in said step (10-30) said driver assistance function is inhibited by temporarily prohibiting its use.

3. Method according to claim 1, characterized in that in said step (10-30) said chosen limit speed is equal to 255 km / h.

4. Product computer program comprising a set of instructions which, when executed by processing means, is suitable for implementing the control method according to any one of claims 1 to 3, in a land vehicle (V) comprising i) a powertrain with an electric motor machine (EMM) and controlled by a control device (DC4) having forward and reverse positions associated respectively with opposite theoretical directions of travel of said vehicle (V), and ii) at least one driver assistance function enabling the establishment of a speed limit, to control the use of said driver assistance function.

5. Control device (DC3) for a land vehicle (V) comprising i) an electric motor drive (EMD) powertrain controlled by a control device (DC4) having forward and reverse positions associated respectively with opposite theoretical directions of travel of said vehicle (V), and ii) at least one driver assistance function enabling the establishment of a speed limit, characterized in that it comprises at least one processor (PR1) and at least one memory (MD) arranged to perform the operations consisting, when said driving assistance function is used and said vehicle (V) has an effective direction of movement opposite to the theoretical direction of movement associated with the current position of said control device (DC4), of triggering an inhibition of said driving assistance function.

6. Land vehicle (V) comprising i) a powertrain with an electric motor machine (EMM) and controlled by a control device (DC4) having forward and reverse positions associated respectively with opposite theoretical directions of travel of said vehicle (V), and ii) at least one driving assistance function enabling the establishment of a speed limit, characterized in that it further comprises a control device (DC4) according to claim 5.

7. Land vehicle according to claim 6, characterized in that said powertrain further comprises a thermal engine (TE).

8. Land vehicle according to claim 6 or 7, characterized in that it is of the automobile type.

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