Control of the failure diagnosis function of a driving assistance function of a vehicle

Abstract

The invention relates to a control method implemented in a vehicle comprising a power train including a heat engine capable of being coupled to a manual gearbox, at least one driving assistance function capable, in the event of activation, of controlling movements of the vehicle by generating a torque setpoint for the power train, and a diagnostic function capable, when the torque setpoint is not comprised between minimum and maximum torques achievable by the power train, of generating an alert message preventing the use of this torque setpoint. This method comprises a step (10-30) in which, each time the gearbox undergoes a gear change, the diagnostic function is temporarily inhibited in order to prevent it from generating the alert message.

Description

DESCRIPTION TITLE: CHECKING THE FAILURE DIAGNOSTIC FUNCTION OF A VEHICLE DRIVING ASSISTANCE FUNCTION The present invention claims priority from French application No. 2302547 filed on 20.03.2023, the content of which (text, drawings and claims) is incorporated herein by reference. Technical field of the invention

[0001] The invention relates to vehicles comprising at least one driving assistance function and a powertrain (or GMP) with a thermal engine associated with a manual gearbox, and more specifically to the control of the use of a fault diagnosis function of such a driving assistance function. State of the art

[0002] Some vehicles, possibly of the automobile type, include:

[0003] - a powertrain (or GMP) comprising a thermal engine suitable for being coupled to a manual gearbox, and

[0004] - at least one specific driving assistance function, if activated, to control movements by generating a torque setpoint for the GMP.

[0005] As is known to those skilled in the art, for the torque setpoint generated by a driving assistance function to be used in the GMP, it must be between the minimum and maximum torques achievable by the GMP. It should be noted that here, the term "torque achievable by the GMP" means the torque that the GMP is capable of providing at the output of its gearbox, for example to rotate the drive wheels in the case of a land vehicle.

[0006] The vehicles described above therefore include a diagnostic function which is specific, when a torque instruction generated by a driving assistance function is not between the minimum and maximum torques achievable by the GMP, to generate an alert message prohibiting the use of this generated torque setpoint. In fact, it is considered that in this situation the driving assistance function is faulty and therefore for safety reasons the torque setpoint it has just generated must not be used in the GMP.

[0007] A disadvantage of this mode of operation lies in the fact that each time the (manual) gearbox is subject to a gear change, the torque setpoint generated by a driving assistance function is higher than the maximum torque that can be achieved at the time in question by the GMP. Indeed, during a gear change, the driver's pressure on the clutch pedal causes the transmission chain of which the GMP is a part to open, and therefore the latter is unable to provide torque at the output of its gearbox.Consequently, the maximum torque (like the minimum torque) achievable by the GMP is equal to zero, and therefore the torque setpoint generated by a driving assistance function is greater than the maximum torque achievable by the GMP, which causes the diagnostic function to generate an alert message which results not only in a prohibition on the use of this torque setpoint, but also in a deactivation of the driving assistance function considered to be faulty. Such deactivation, generally unnecessary, can prove dangerous for the vehicle and its passengers because it deprives them of a potentially essential driving aid.

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

[0009] For this purpose, it proposes in particular a control method intended to be implemented in a vehicle comprising:

[0010] - a powertrain comprising a thermal engine suitable for being coupled to a manual gearbox,

[0011] - at least one specific driving assistance function, when activated, for controlling vehicle movements by generating a torque setpoint for the powertrain, and

[0012] - a specific diagnostic function, when this torque setpoint is not between the minimum and maximum torques achievable by the powertrain, to generate an alert message prohibiting the use of the torque setpoint.

[0013] This control method is characterized by the fact that it includes a step in which, each time the gearbox is changed gear, the diagnostic function is temporarily inhibited to prevent it from generating the alert message.

[0014] Thanks to this inhibition of the diagnostic function during each gear change, the torque instruction generated by the driving assistance function no longer risks being rejected, and therefore there is no longer any risk of deactivating this driving assistance function, and consequently no longer any risk of depriving the vehicle and its passengers of potentially essential driving assistance.

[0015] The control method according to the invention may include other characteristics which may be taken separately or in combination, and in particular:

[0016] - in a first embodiment, in its step, the diagnostic function can be inhibited for a predefined duration;

[0017] - in this first embodiment, in its step, the predefined duration can be between 5 seconds and 12 seconds;

[0018] - in a second embodiment, in its step, the diagnostic function can be inhibited between a first instant of detection of a start of the gear change and a second instant of detection of an end of the gear change;

[0019] - in this second embodiment, in its step, the first detection instant may correspond to a detection instant of a percentage of depression of a clutch pedal of the vehicle, controlling a clutch suitable for coupling the thermal engine to the gearbox, greater than a first threshold, and the second detection time may correspond to a detection time of a percentage of depression of the clutch pedal less than a second threshold in the presence of a new ratio recognized in the gearbox;

[0020] - in its stage, each driving assistance function can be chosen from an adaptive cruise control function and a trajectory control function.

[0021] The invention also proposes a computer program product comprising a set of instructions which, when executed by processing means, is capable of implementing a control method of the type presented above, in a vehicle comprising, on the one hand, a powertrain comprising a thermal engine suitable for being coupled to a manual gearbox, on the other hand, at least one driving assistance function suitable, in the event of activation, for controlling movements of the vehicle by generating a torque setpoint for the powertrain, and on the other hand, a diagnostic function suitable, when this torque setpoint is not between minimum and maximum torques achievable by the powertrain, for generating an alert message prohibiting the use of the torque setpoint, to control the use of this diagnostic function.

[0022] The invention also proposes a control device intended to equip a vehicle comprising:

[0023] - a powertrain comprising a thermal engine suitable for being coupled to a manual gearbox,

[0024] - at least one specific driving assistance function, when activated, for controlling vehicle movements by generating a torque setpoint for the powertrain, and

[0025] - a specific diagnostic function, when this torque setpoint is not between the minimum and maximum torques achievable by the powertrain, to generate an alert message prohibiting the use of the torque setpoint.

[0026] This control device is characterized by the fact that it comprises at least one processor and at least one memory arranged to carry out the operations consisting, each time the gearbox is subject to a gear change, in triggering a temporary inhibition of the diagnostic function to prevent it from generating the alert message.

[0027] The invention also provides a vehicle comprising:

[0028] - a powertrain comprising a thermal engine suitable for being coupled to a manual gearbox,

[0029] - at least one specific driving assistance function, when activated, to control vehicle movements by generating a torque setpoint for the powertrain,

[0030] - a diagnostic function specific to, when this torque setpoint is not between the minimum and maximum torques achievable by the powertrain, generating an alert message prohibiting the use of the torque setpoint, and

[0031] - a control device of the type presented above.

[0032] For example, this vehicle may be of the automobile type. Brief description of the figures

[0033] Other characteristics and advantages of the invention will appear on examining the detailed description below, and the appended drawings, in which:

[0034] [Fig. 1] schematically and functionally illustrates an exemplary embodiment of a land vehicle comprising a GMP, with a thermal motor associated with a manual gearbox, a supervision computer, a driving assistance computer, a diagnostic function, and a control device according to the invention,

[0035] [Fig. 2] schematically and functionally illustrates an exemplary embodiment of a supervision computer comprising an exemplary embodiment of a control device according to the invention, and

[0036] [Fig. 3] schematically illustrates an example of an algorithm implementing a control method according to the invention. Detailed description of the invention

[0037] The invention aims in particular to propose a control method, and an associated DC control device, intended to allow the control in a vehicle V, with GMP with manual gearbox, of the use of a function FD for diagnosing the failure of at least one driving assistance function FAC.

[0038] In the following, it is considered, by way of non-limiting example, that the vehicle V is of the automobile type. It is for example a car, as illustrated in Figure 1. But the invention is not limited to this type of vehicle. It relates in fact to any type of vehicle (land, sea (or river), or air) comprising a powertrain (or GMP) with a manual gearbox associated with a clutch, at least one driving assistance function, and a function for diagnosing the failure of the latter.

[0039] Figure 1 schematically shows a vehicle (here land) V comprising a GMP transmission chain with a thermal engine MMT and clutch EB associated with a manual gearbox BV, a supervision computer CS, a driving assistance computer CF, a diagnostic function FD, and a control device DC according to the invention.

[0040] It should be noted that the GMP could also be of the hybrid type (electric and thermal). The transmission chain could also allow a four-wheel drive mode (or 4x4).

[0041] As shown, the drive chain also includes, here, an AM drive shaft and an AT drive shaft.

[0042] The operation of the transmission chain (and therefore of the GMP) is supervised by the CS supervision computer.

[0043] The GMP being here purely thermal, as an illustrative example, it comprises a thermal motor MMT comprising a crankshaft (not shown) which is fixedly secured to the motor shaft AM in order to drive the latter (AM) in rotation. This thermal motor MMT is clean to operate according to a regime to provide a first torque, on order of the supervision computer CS. In addition, it (MMT) is capable of being coupled to the primary shaft AP of the gearbox BV (manual) by the clutch EB. The latter (EB) is capable of delivering a second torque from the first torque produced by the thermal motor MMT, in particular for at least one train T1 of driving wheels.

[0044] For example, the train T1 can be located in the front part PW of the vehicle V. It is preferably, and as illustrated, coupled to the transmission shaft AT via a differential (here front) DV. But in a variant this train T1 could be the one referenced T2 which is located in the rear part PRV of the vehicle V.

[0045] The driving assistance computer CF provides at least one driving assistance function FAC which makes it possible to control movements of the vehicle V in phases of possibly autonomous driving. For example, this (one) driving assistance function FAC may be responsible for regulating the speed of the vehicle V and the distance between vehicles (it is then often designated by the English acronym ACC ("Adaptive Cruise Control")). Alternatively, the (one) driving assistance function FAC may be a trajectory control function, for example of the ESP / ABS type (ESP: "Electronic Stability Program"), ABS: "Anti-Blocking System")). But the vehicle V could include one or more other driving assistance function(s).

[0046] In a driving phase that is at least partly autonomous, controlled by a driving assistance function FAC, the supervision computer CS sends to this driving assistance function FAC at least the minimum torques cmin and maximum torques cmax that are achievable by the GMP, and an estimate of the torque that is supplied by the GMP at the output of the gearbox BV (and therefore here to the drive wheels of the front axle T1).

[0047] It should be noted that here we mean by "torque achievable by the GMP" the torque that the GMP is capable of providing at the output of its gearbox BV, here to rotate the drive wheels of the front axle T1. On receipt of these minimum cmin and maximum cmax torques and estimation of torque, the driving assistance function FAC determines for the supervision computer CS a torque setpoint ccg which defines the torque that it wants the GMP to supply (here) to the drive wheels and which must be between the minimum torques cmin and maximum cmax.

[0048] It will be noted that the driving assistance computer CF and the supervision computer CS can, for example, communicate via an internal communication network RC of the vehicle V, possibly multiplexed, as illustrated non-limitingly in figure 1.

[0049] The diagnostic function FD is responsible for detecting failures of at least one driving assistance function FAC. More precisely, this diagnostic function FD is arranged, when a torque setpoint ccg, just generated by the (one) driving assistance function FAC, is not between the minimum torques cmin and maximum torques cmax achievable by the GMP, so as to generate an alert message prohibiting the use of this generated torque setpoint ccg and triggering a deactivation of this driving assistance function FAC. It is in fact considered that the driving assistance function FAC is faulty and therefore that the torque setpoint that it has just generated must not be used in the GMP for the safety of the vehicle V and its passengers.

[0050] In the example illustrated non-limitingly in Figures 1 and 2, the diagnostic function FD is part of the supervision computer CS. But this is not obligatory. Indeed, the diagnostic function FD could include its own dedicated computer, which is then coupled to the supervision computer CS, or could be part of another computer on board the vehicle V and providing at least one other function, for example.

[0051] As mentioned above, the invention proposes in particular a control method intended to enable the control of the use of the diagnostic function FD associated with at least one driving assistance function FAC of the vehicle V.

[0052] This (control) method can be implemented at least partially by the control device DC (illustrated at least partially in Figures 1 and 2) which comprises for this purpose at least one processor PR1, for example digital signal (or DSP ("Digital Signal Processor")), and at least one MD memory. This DC control device can therefore be implemented in the form of a combination of electrical or electronic circuits or components (or "hardware") and software modules (or "software"). For example, it can be a microcontroller.

[0053] The MD memory is RAM in order to store instructions for the implementation by the processor PR1 of at least part of the control method. The processor PR1 may comprise integrated (or printed) circuits, or several integrated (or printed) circuits connected by wired or wireless connections. An integrated (or printed) circuit is understood to mean any type of device capable of carrying out at least one electrical or electronic operation.

[0054] In the example illustrated non-limitingly in Figures 1 and 2, the control device DC is part of the supervision computer CS. But this is not obligatory. Indeed, the control device DC could include its own dedicated computer, which is then coupled to the supervision computer CS, or could be part of another computer on board the vehicle V and providing at least one other function, for example.

[0055] As illustrated non-limitingly in Figure 3, the (control) method according to the invention comprises a step 10-30 which is implemented each time a driving assistance function FAC of the vehicle V is active.

[0056] Step 10-30 of the method comprises a sub-step 20 in which, each time the gearbox BV is subject to a gear change, the diagnostic function FD is temporarily inhibited (for example the DC control device triggers a temporary inhibition of) to prevent it from generating its alert message.

[0057] Since the FD diagnostic function is now temporarily inhibited during each gear change, the torque setpoint ccg generated by the FAC driving assistance function no longer risks being rejected, even if it is higher than the maximum torque cmax achievable at the time considered by the GMP due to the opening of the transmission chain caused by the driver pressing the PE clutch pedal. In addition, there is no longer any risk of deactivating this FAC driving assistance function, and therefore more risk of depriving the vehicle V and its passengers of potentially essential driving assistance.

[0058] It will be noted that at the end of the temporary inhibition of the FD diagnostic function, the latter (FD) is reactivated (or disinhibited), for example by the DC control device in a sub-step 20 of step 10-30.

[0059] For example, and as illustrated non-limitingly in Figure 3, the method may also comprise a sub-step 10 in which one (the DC control device) may be informed of the start of a gear change, which triggers the performance of sub-step 20 (temporary inhibition of the FD diagnostic function).

[0060] At least two different embodiments can be envisaged for temporary inhibition.

[0061] In a first embodiment, in sub-step 20 of step 10-30 it is possible to inhibit (for example the DC control device can trigger an inhibition of) the FD diagnostic function for a predefined duration. This predefined duration is chosen so that the driver of the vehicle V has ample time to carry out his gear change.

[0062] It will be noted that in this first embodiment one (for example the DC control device) does not need to be informed of the end of the gear change. Automatically, upon expiry of the predefined duration, the inhibition of the FD diagnostic function will end, for example by the generation in a sub-step 30 of step 10-30 of a message for reactivating the FD diagnostic function (for example by the DC control device).

[0063] For example, this predefined duration can be between 5 seconds and 12 seconds. As an illustrative example, the predefined duration can be equal to 10 seconds. But other predefined durations can be used (shorter or longer than those mentioned above).

[0064] In a second embodiment, in sub-step 20 of step 10-30 it is possible to inhibit (for example the DC control device can trigger an inhibition of) the FD diagnostic function between a first instant id1 of detection of a start of the gear change and a second instant id2 of detection of an end of the gear change.

[0065] For example, in sub-step 20 of step 10-30 the first detection instant id 1 may correspond to a detection instant of a percentage of depression of the clutch pedal PE of the vehicle V, which controls the clutch EB (suitable for coupling the thermal motor MMT to the gearbox BV), greater than a first threshold s1, and the second detection instant id2 may correspond to a detection instant of a percentage of depression of the clutch pedal PE less than a second threshold s2 in the presence of a new ratio recognized in the gearbox BV.

[0066] Preferably, the first detection time id1 is that mentioned above in the description of sub-step 10, i.e. the time when the start of the gear change is informed.

[0067] Also for example, the first threshold s1 can be between 15% and 25% of clutch pedal depression PE. As an illustrative example, the first threshold s1 can be equal to 20% of clutch pedal depression PE. But other values ​​of first threshold s1 can be used (more or less important than those mentioned above).

[0068] Also for example, the second threshold s2 can be between 20% and 30% of clutch pedal depression PE. As an illustrative example, the second threshold s2 can be equal to 25% of clutch pedal depression PE. But other values ​​of second threshold s2 can be used (more or less important than those mentioned above).

[0069] It will be noted that in the second embodiment, once one (for example the DC control device) has been informed of the end of the gear change at the second detection instant id2 and of the recognition of the new gear established in the gearbox BV, one (for example the DC control device) can generate a message for reactivating the diagnostic function FD in sub-step 30 of step 10-30.

[0070] It will also be noted, as illustrated non-limitingly in Figure 2, that the supervision computer CS (or the computer of the control device DC) can also include a mass memory MM1, in particular for storing the first detection instant id1, as well as any intermediate data involved in all its calculations and processing. Furthermore, this supervision computer CS (or the computer of the control device DC) may also comprise an input interface IE for receiving at least the information signaling the start of the gear change (or the first detection instant id1) and the possible message signaling the recognition of the new gear set in the gearbox BV, possibly after having formatted and / or demodulated and / or amplified them, in a manner known per se, by means of a digital signal processor PR2. In addition, this supervision computer CS (or the computer of the control device DC) may also comprise an output interface IS, in particular for delivering each message for inhibiting the diagnostic function FD and each message for reactivating the diagnostic function FD.

[0071] 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 electronic circuit (or hardware) type, such as for example the processor PR1, is capable of implementing the control method described above to control in the vehicle V the use of the diagnostic function FD responsible for detecting the failures of at least one driving assistance function FAC.

Claims

CLAIMS

1. Control method for a vehicle (V) comprising i) a powertrain comprising a thermal motor (MMT) suitable for being coupled to a manual gearbox (BV), ii) at least one driving assistance function suitable, in the event of activation, for controlling movements of said vehicle (V) by generating a torque setpoint for said powertrain, and ll) a diagnostic function suitable, when said torque setpoint is not between minimum and maximum torques achievable by said powertrain, for generating an alert message prohibiting the use of said torque setpoint, characterized in that it comprises a step (10-30) in which, each time said gearbox (BV) is subject to a gear change, said diagnostic function is temporarily inhibited to prevent it from generating said alert message.

2. Method according to claim 1, characterized in that in said step (10-30) said diagnostic function is inhibited for a predefined duration.

3. Method according to claim 2, characterized in that in said step (10-30) said predefined duration is between 5 seconds and 12 seconds.

4. Method according to claim 1, characterized in that in said step (10-30) said diagnostic function is inhibited between a first instant of detection of a start of said gear change and a second instant of detection of an end of said gear change.

5. Method according to claim 4, characterized in that in said step (10-30) said first detection instant corresponds to a detection instant of a percentage of depression of a clutch pedal (PE) of said vehicle (V), controlling a clutch (EB) suitable for coupling said thermal motor (MMT) to said gearbox (BV), greater than a first threshold, and said second detection instant corresponds to a detection instant of a percentage of depression of said clutch pedal (PE) less than a second threshold in the presence of a new ratio recognized in said gearbox (BV).

6. Method according to one of claims 1 to 5, characterized in that in said step (10-30) each driving assistance function is chosen from an adaptive cruise control function and a trajectory control function.

7. Computer program product comprising a set of instructions which, when executed by processing means, is capable of implementing the control method according to one of claims 1 to 6, in a vehicle (V) comprising i) a powertrain comprising a thermal motor (MMT) capable of being coupled to a manual gearbox (BV), ii) at least one driving assistance function capable, in the event of activation, of controlling movements of said vehicle (V) by generating a torque setpoint for said powertrain, and ll) a diagnostic function capable, when said torque setpoint is not between minimum and maximum torques achievable by said powertrain, of generating an alert message prohibiting the use of said torque setpoint, to control the use of said diagnostic function.

8. Control device (DC) for a vehicle (V) comprising i) a powertrain comprising a thermal motor (MMT) suitable for being coupled to a manual gearbox (BV), ii) at least one driving assistance function suitable, in the event of activation, for controlling movements of said vehicle (V) by generating a torque setpoint for said powertrain, and ll) a diagnostic function suitable, when said torque setpoint is not between minimum and maximum torques achievable by said powertrain, for generating an alert message prohibiting the use of said torque setpoint, characterized in that it comprises at least one processor (PR1) and at least one memory (MD) arranged to carry out the operations consisting, each time said gearbox (BV) is subject to a gear change,to trigger a temporary inhibition of said diagnostic function to prevent it from generating said alert message.,

9. Vehicle (V) comprising i) a powertrain comprising a thermal motor (MMT) suitable for being coupled to a manual gearbox (BV), ii) at least one driving assistance function capable, in the event of activation, of controlling movements of said vehicle (V) by generating a torque setpoint for said powertrain, and ll) a diagnostic function capable, when said torque setpoint is not between the minimum and maximum torques achievable by said powertrain, of generating an alert message prohibiting the use of said torque setpoint, characterized in that it further comprises a control device (DC) according to claim 8.

10. Vehicle according to claim 9, characterized in that it is of the automobile type.

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