A method for controlling a road vehicle when the drive wheels slip.

Abstract

To provide a method for controlling a road vehicle during a slip of drive wheels.SOLUTION: The method has the steps of: detecting a slip of at least one drive wheel (3); and controlling, only during a slip of at least one drive wheel (3), a driving unit of the road vehicle (1) with a signaling law to obtain a cyclic operating irregularity which generates an abnormal vibration and / or abnormal noise.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] (Cross - reference to related applications) This patent application claims the priority of Italian Patent Application No. 102021000003872 filed on February 19, 2021, and the entire disclosure of this Italian patent application is incorporated herein by reference.

[0002] The present invention relates to a method for controlling a road vehicle during slip of a driving wheel.

[0003] The present invention is advantageously applicable to motor vehicles and will be explicitly referred to as such in the following description, but such reference does not imply loss of generality.

Background Art

[0004] Modern motor vehicles are equipped with an electronic traction control system recognized by the acronym ASR ("Anti - Slip Regulation" or "Anti - Spin Regulation") or the acronym TCS ("Traction Control System"). The electronic traction control system periodically measures the rotational speed of each wheel, compares the rotational speeds of all the wheels, and recognizes that there is slip when a driving wheel rotates faster than other wheels (especially the driven wheels), and basically deals with it by reducing the torque generated by the internal combustion engine.

[0005] In a spark - ignition internal combustion engine operating according to the Otto cycle, the reduction of torque is obtained by reducing the air supply and thus reducing the fuel supply in response to the reduction of the air supply, and can also be obtained by operating the ignition advance angle at the first instant (for a more rapid intervention).

[0006] Current traction control systems are highly effective and versatile because they not only completely eliminate drive wheel slip but can also maintain a small, predetermined (i.e., desirable) slip state in the drive wheels for a limited time (for example, when starting a parked vehicle or when a vehicle is slightly yawing due to oversteer and going around a curve).

[0007] Generally, car instrument panels have light indicators that illuminate to warn the driver when traction control is activated due to slippage of the drive wheels. However, this signal can be mistaken for something else, or even completely ignored, especially when the driver is attempting to achieve a professional level of performance and is therefore highly focused on the road ahead rather than the instrument panel. Furthermore, the light indicators that signal traction control intervention usually do not illuminate when the drive wheel slip is "under control" (i.e., maintained at a small, predetermined level).

[0008] European Patent Application Publication No. 2505414 discloses a motorcycle equipped with a traction control system that reduces the torque applied to the rear wheel when the slip coefficient of the rear wheel exceeds a first threshold, and further, when the slip coefficient exceeds a second threshold (smaller than the first threshold), a warning for the driver is also generated by vibration of the throttle valve, causing a corresponding vibration of the torque applied to the rear wheel.

[0009] European Patent Application Publication No. 0443785 and UK Patent Application Publication No. 2317716 describe an automobile equipped with a traction control system that reduces the torque applied to the drive wheels when the drive wheels slip, in particular by periodically turning off one or more cylinders, i.e., by avoiding the injection of fuel into one or more cylinders. However, the forms of traction control disclosed in European Patent Application Publication No. 0443785 and UK Patent Application Publication No. 2317716 determine a very noticeable irregularity in the operation of the internal combustion engine, which may be considered excessive and almost uncomfortable by the driver, on the one hand, and may damage both the transmission and exhaust system over time. [Overview of the Initiative] [Problems that the invention aims to solve]

[0010] The object of the present invention is to provide a method for controlling a road vehicle when the drive wheels slip, which improves the communication between the driver and the vehicle when the drive wheels slip, and at the same time provides a control method that can be easily and economically implemented. [Means for solving the problem]

[0011] According to the present invention, a method for controlling a road vehicle in the event of slippage of the drive wheels is provided, as described in the appended claims. In other words, the present invention includes, for example, the following embodiments. (Section 1) To control a road vehicle (1) when the drive wheels (3) rotated by the engine slip, Steps include detecting slippage of at least one drive wheel (3), A step of controlling the engine by a law of notification due to imbalance in order to obtain periodic operational irregularities that produce abnormal vibrations and / or abnormal noises perceptible to the driver only when at least one drive wheel (3) slips, A method that includes, A further step is to keep the desired time frequency of the abnormal vibration and / or the abnormal noise substantially constant, even when the rotational speed (ω) of the engine changes, and A further step of activating the disparity notification law, which has a target constant desired time frequency even when the rotational speed (ω) of the engine changes. A control method characterized by including (Section 2) The control method according to item 1, wherein the notification rule is accompanied by periodically activating an impulsive deviation event (E), the impulsive deviation event (E) causing the abnormal vibration and / or the abnormal noise, and having a constant desired time frequency which is a divisor of the desired time frequency of the abnormal vibration and / or the abnormal noise. (Section 3) The control method according to item 2, wherein the desired time frequency of the deviation event (E) is in the range of 5 to 32 Hz. (Section 4) The control method according to item 2 or 3, wherein the desired time frequency of the abnormal vibration is not a multiple or divisor of the resonant frequency of the engine or the components of the road vehicle (1). (Section 5) A further step of checking in advance whether the desired time frequency may cause resonance in the engine or components of the road vehicle (1), To ensure that the desired time frequency of the abnormal vibration does not cause resonance in the engine or components of the road vehicle (1), a further step is to modify the desired time frequency of the notification rule. A control method described in any one of items 2 to 4, including the control method described in item 2 to 4. (Section 6) A further step is to determine the desired torque required by the driver of the aforementioned road vehicle (1): A further step of controlling the engine to generate a normal torque equal to the desired torque when there is no slippage of the drive wheel (3), and A further step of controlling the engine to generate a reduced torque, i.e., a torque smaller than the desired torque, only when at least one drive wheel (3) is slipping. A control method according to any one of items 1 to 5, including the method described in item 1 to 5. (Section 7) The control method according to paragraph 6, wherein, only when at least one drive wheel (3) slips, the reduction in torque generated by the engine with respect to the desired torque acts on the engine, ensuring the normal balanced operation of the engine and obtained by limiting operation independent of the notified law. (Section 8) The control method according to paragraph 7, wherein the engine is controlled by the notification rule, which is independent of the limiting action and applied autonomously to the limiting action, only when at least one drive wheel (3) is slipping, and simultaneously with a reduction in the torque generated by the engine, causing the engine to operate in an abnormal manner and generating abnormal vibration and / or abnormal noise that is perceptible to the driver. (Section 9) The control method according to any one of claims 1 to 8, wherein the notification rule involves periodically activating an impulsive deviation event (E) that determines an impulsive gap in the torque generated by the engine. (Section 10) The engine comprises an internal combustion engine (4) equipped with a plurality of cylinders (11) and a plurality of fuel injectors (16) each that inject fuel into the corresponding cylinder (11). The control method according to item 9, wherein the impulsive deviation event (E) consists of at least one incomplete injection or absence of injection of fuel to a single cylinder (11) that determines incomplete combustion or absence of combustion in the cylinder (11), followed by a plurality of normal injections in subsequent cylinders (11) in the ignition sequence. (Section 11) The control method according to item 10, wherein the impulsive deviation event (E) consists of at least one incomplete injection or absence of injection of fuel to a single cylinder (11) that determines incomplete combustion or absence of combustion in the cylinder (11), followed by at least 15 normal injections in subsequent cylinders (11) in the ignition sequence. (Section 12) To control a road vehicle (1) when the drive wheels (3) rotated by the engine slip, The steps include determining the desired torque required by the driver of the road vehicle (1), Steps include detecting slippage of at least one drive wheel (3), The steps include controlling the engine to generate a normal torque equal to the desired torque when there is no slippage of the drive wheel (3), The steps include controlling the engine to generate a reduced torque, i.e., a torque smaller than the desired torque, only when at least one drive wheel (3) is slipping, and It includes, A method wherein, only when at least one drive wheel (3) slips, the reduction in torque generated by the engine with respect to the desired torque is achieved by a limiting action that acts on the engine and ensures the normal balanced operation of the engine, A further step of controlling the engine by a notification rule that, only when at least one drive wheel (3) is slipping, simultaneously with a reduction in the torque generated by the engine, is independent of the limiting action, is applied autonomously to the limiting action, and causes the engine to operate in an abnormal manner, generating abnormal vibrations and / or abnormal noises that are perceptible to the driver. A control method characterized by including (Section 13) The notification rule involves periodically activating an impulsive deviation event (E) that determines an impulsive gap in the torque generated by the engine. The engine comprises an internal combustion engine (4) equipped with a plurality of cylinders (11) and a plurality of fuel injectors (16) each that inject fuel into the corresponding cylinder (11). The aforementioned limiting action is applied to all cylinders (11) simultaneously in the same manner, that is, the limiting action involves operating all cylinders (11) in the same manner at the same moment. The control method according to item 12, wherein the impulsive deviation event (E) consists of an incomplete injection or absence of injection of fuel into a single cylinder (11) that determines incomplete combustion or absence of combustion in the cylinder (11), followed by a plurality of normal injections in subsequent cylinders (11) in the ignition sequence.

[0012] The attached claims describe preferred embodiments of the present invention and form an integral part of this specification. [Brief explanation of the drawing]

[0013] Next, the present invention will be described with reference to the accompanying drawings illustrating some embodiments (but not limited to) of the present invention.

[0014] [Figure 1] This is a schematic diagram of an automobile equipped with an internal combustion engine and implementing the control method according to the present invention. [Figure 2] Figure 1 is a perspective view of an internal combustion engine in an automobile. [Figure 3] Figure 2 is a schematic diagram of the bank of an internal combustion engine. [Figure 4] Figure 2 is a schematic diagram of both banks of the internal combustion engine. [Figure 5] This is a time diagram showing the time evolution of several feature quantities of the internal combustion engine in Figure 2 during the execution of the method according to the present invention. [Figure 6] This is a schematic diagram of an automobile equipped with an electric motor and implementing the control method according to the present invention. [Figure 7] Figure 6 is a schematic diagram of the stator windings of an electric motor in an automobile. [Modes for carrying out the invention]

[0015] In Figure 1, number 1 represents a road vehicle (specifically, an automobile) as a whole, comprising two front driven wheels (i.e., non-driven wheels) 2 and two rear driven wheels 3. An internal combustion engine 4 is located at the front, which constitutes the drive unit of the automobile 1, and comprises a drive shaft 5 that generates torque transmitted to the drive wheels 3 by the drive system 6. Specifically, the internal combustion engine 4 is a spark-ignition engine, operates according to the Otto cycle, and uses gasoline as fuel. The drive system 6 comprises a dual-clutch servo-assisted transmission 7 located within the rear-wheel drive assembly and a transmission shaft 8 that connects the drive shaft 5 to the input of the dual-clutch servo-assisted transmission 7. The dual-clutch servo-assisted transmission 7 is connected in a row to a self-locking differential 9, from which a pair of axles, each integrated with a drive wheel 3, begin.

[0016] As shown in Figure 2, the internal combustion engine 4 is of the "V12" type and has two (twin) banks 10, each consisting of six cylinders 11 ( schematically shown in Figure 3), arranged at an angle to each other to form a 90° "V" shape. In each bank 10, the six cylinders 11 are connected to an intake manifold 12 by at least one intake valve (not shown) and to an exhaust manifold 13 by at least one exhaust valve (not shown), each exhaust manifold 13 collecting combustion gases that periodically flow out from the exhaust valve.

[0017] As shown in Figure 1, each exhaust manifold 13 is connected to a corresponding exhaust duct 14, which receives the gases produced by combustion from the exhaust manifold 13 and releases them into the atmosphere. Each exhaust duct 14 starts from the corresponding exhaust manifold 13 and ends in the tail region of the vehicle 1. Along each exhaust duct 14, there is a known exhaust gas treatment device 15, which always contains at least one catalytic converter and may also contain a particulate filter (in order to comply with the new EURO6C standard for polluting emissions, vehicle manufacturers use a particulate filter called a "Gasoline Particulate Filter," or GPF, even in gasoline engines).

[0018] At the end of each exhaust duct 14, there is a silencer equipped with an outlet pipe that constitutes the end of the exhaust duct 14. Each outlet pipe is generally connected to a decorative tailpipe that serves only a decorative function (i.e., to conceal the outlet pipe in a desirable shape that harmonizes with the background of the automobile 1).

[0019] According to Figure 3, the internal combustion engine 4 is equipped with a fuel supply system, which includes (at least) a corresponding injector 16 for each cylinder 11 that supplies fuel to the cylinder 11.

[0020] As shown in Figure 1, a control system 17 is provided for the internal combustion engine 4, comprising two twin electronic control units 18, which are physically independent and isolated from each other, connected to each other via a field bus 19 (generally operating according to the CAN standard - "Controller Area Network"), and each controls the corresponding bank 10. One electronic control unit 18 operates as a "master" (i.e., sets the engine control goals), while the other electronic control unit 18 operates as a "slave" (i.e., copies the engine control goals set by the other electronic control unit 18).

[0021] As shown in Figure 1, the automobile 1 is equipped with a known traction control system 20, which is typically recognized by the acronym ASR ("Anti-Slip Regulation" or "Anti-Spin Regulation") or TCS ("Traction Control System"). The traction control system 20 communicates (also with the control system 17 of the internal combustion engine 4) via a field bus 19 and, when in use, periodically measures the rotational speed of each wheel 2 or 3 and compares the rotational speeds of all wheels 2 and 3 to recognize the presence of slip if the drive wheels 3 are rotating faster than the other wheels 2 and 3 (especially the driven wheels 2), and addresses this (if necessary) essentially by reducing the torque generated by the internal combustion engine 4. The torque reduction is achieved by reducing the air supply (i.e., closing the throttle valve), and consequently by reducing the fuel supply by the same amount (to maintain a constant air-fuel ratio). A reduction in torque can also be achieved by manipulating the ignition advance at the initial moment (for quicker intervention), but this manipulation is only temporary (as mentioned above, only at the initial moment) and is gradually eliminated as the effects of the reduced air and fuel supply increase.

[0022] In other words, the traction control system 20 detects slippage of at least one drive wheel 3, and in the event of slippage of at least one drive wheel 3, appropriately reduces the torque generated by the internal combustion engine 4 in a known manner in order to eliminate the slippage or maintain the slippage at a predetermined desired level.

[0023] Furthermore, the vehicle 1 is equipped with a notification system 21 that controls the drive unit (i.e., the internal combustion engine 4) of the vehicle 1 by an unbalanced signaling law to obtain periodic operational irregularities that produce abnormal (i.e., normally absent) vibrations and noises that are perceptible to the driver and perceptible to the driver. The abnormal vibrations and noises are perceptible to the driver, i.e., strong enough to be (clearly) perceived by the driver (in fact, their original purpose is to be perceived by the driver in order to provide information to the driver, as will be better explained below). In other words, only during slippage of at least one drive wheel 3, the drive unit is controlled by a notification law that is independent of (possible) limiting action, and added to (possible) limiting action in an autonomous manner, causing the drive unit to operate in an abnormal (unbalanced) manner to produce abnormal vibrations and / or noises (through periodic operational irregularities) that are perceptible to the driver.

[0024] As a result, when the drive wheels 3 are slipping (regardless of whether the traction control system 20 is working to reduce torque, since the traction control system 20 may be weakened or disabled by the driver), the notification system 21 acts on the drive unit of the vehicle 1 to obtain periodic irregularities in operation that produce abnormal (i.e., normally absent) vibrations and abnormal (i.e., normally absent) noises that are perceptible to the driver, and the driver, thanks to the abnormal vibrations and noises, recognizes that his current driving has led to the slip of the drive wheels 3 and is therefore able to correct his driving (if his goal was to avoid reaching a slip of the drive wheels 3 that would normally lead to a deterioration in performance), or in any case adjust his driving to a new state (if his goal was to reach a controlled slip of the drive wheels 3 for driving that prioritizes enjoyment over performance).

[0025] It should be noted that the notification system 21 acts on the drive unit of the vehicle 1 to generate abnormal vibrations and noises, regardless of the fact that the traction control system 20 reduces torque (to eliminate or control the slip) when the drive wheel 3 is slipping, the abnormal vibrations and noises warn the driver that his driving has caused the drive wheel 3 to slip (which is probably eliminated or controlled by the reduction in torque), and this warning is useful in both cases: when the traction control system 20 reduces torque (in which case the normal effects of the drive wheel 3 slip are more or less masked by the intervention of the traction control system 20), and when the traction control system 20 does not reduce torque (i.e., is "off"), in which case the driver would not be able to recognize that the drive wheel 3 is slipping anyway. In other words, the traction control system 20 may or may not reduce the torque generated by the drive unit (i.e., the internal combustion engine 4) while at least one drive wheel 3 is slipping, completely independently of the operation of the notification system 21 which activates the notification law due to imbalance (which serves the sole function of generating abnormal vibration and abnormal noise).

[0026] According to another embodiment, the notification system 21 intervenes by activating the unbalance notification law only at the same time as the intervention of the traction control system 20, that is, only when the traction control system 20 intervenes to limit the torque.

[0027] The operation of the disbalance notification law serves the sole purpose of generating abnormal vibrations and noises to provide the driver with appropriate feedback about the presence of slip in the drive wheels 3. As will be explained in more detail below, the operation of the disbalance notification law may also cause a (small, insignificant) reduction in torque that disrupts the normal operation of the drive unit (i.e., the internal combustion engine 4) in any case, but this (small, insignificant) reduction in torque is an unexpressly desired and unsought "side effect" (which is by no means harmful, as this "side effect" tends to reduce the slip in the drive wheels 3, which is an undesirable phenomenon in any case, even if only to a minimal and almost insignificant extent). In fact, the torque reduction caused by the disbalance notification law is generally within the range of a few percent and therefore does not have a significant (meaningful) effect on the slip in the drive wheels 3.

[0028] In other words, when in use, the desired torque requested by the driver of the road vehicle 1 is determined (primarily as a function of the position of the accelerator pedal), slip of at least one drive wheel 3 is periodically detected, and the drive unit is controlled to generate a normal torque equal to the desired torque when there is no slip of the drive wheel 3, while the drive unit is controlled to generate a reduced torque, i.e., a torque smaller than the desired torque, only when there is slip of at least one drive wheel 3, through the intervention of the traction control system 20 (of course, only when the traction control system 20 actually intervenes).

[0029] Therefore, only during the slip of at least one drive wheel 3, a reduction in the torque generated by the drive unit relative to the desired torque is obtained through a limiting action (provided by the traction control system 20) acting on the drive unit, (since the limiting action is applied to all cylinders 11 simultaneously in the same identical manner, i.e., the limiting action acts on all cylinders 11 at the same moment and in the same manner) the normal balanced operation of the drive unit is maintained, and as described above, this limiting action (provided by the traction control system 20) is always accompanied by a reduction in airflow and may also be accompanied by a temporary (only at the first moment) intervention on the ignition advance angle.

[0030] Furthermore, only during the slip of at least one drive wheel 3, regardless of the operation of the traction control system 20 (i.e., regardless of the reduction in torque generated by the drive unit), the notification system 21 also controls the drive unit by a notification law of imbalance that is completely independent of the limiting action and is added to the limiting action in an autonomous manner (if a limiting action exists), causing periodic operational irregularities that generate abnormal vibrations and / or abnormal noises (unrelated to the reduction in torque determined by the limiting action).

[0031] According to a preferred embodiment, the limiting system 21 keeps the (dominant, i.e., first harmonic) time frequency of abnormal vibrations and noises constant (as much as possible) even when the rotational speed ω of the drive unit (i.e., the internal combustion engine 4) changes. In other words, the limiting system 21 controls the drive unit (i.e., the internal combustion engine 4) by an unbalanced notification law that is always adjusted to the rotational speed ω of the drive unit so that the (dominant, i.e., first harmonic) time frequency of abnormal vibrations and noises remains constant (as much as possible). The term time frequency represents the number of times an event is repeated in a given time unit, i.e., a frequency evaluated on a time basis.

[0032] In other words, while the desired time-frequency of abnormal vibration and noise is always the same regardless of the rotational speed ω of the drive unit, the operation of abnormal vibration and noise (which is performed with the target time-frequency) was not possible to precisely obtain the desired time-frequency (i.e., it was impossible to perform the control perfectly, so the actual time-frequency could differ slightly from the desired time-frequency).

[0033] By keeping the (primary, i.e., first harmonic) time frequency of abnormal vibrations and noises constant, the feedback perceived by the driver is improved, which is to say that, from the driver's perspective, it does not make sense that the feedback notifying of slippage of drive wheel 3 should be heavier simply because the drive unit is rotating at a lower speed, or abrupter simply because the drive unit is rotating at a higher speed.

[0034] In particular, the law of notification due to imbalance involves the periodic operation of impulsive deviation events E (shown in Figure 5) which have a constant time frequency even when the rotational speed ω of the drive unit changes (as shown in Figure 5), and the time frequency of the impulsive deviation events E is consequently a divisor of the time frequency of the abnormal vibration and abnormal noise. According to a preferred embodiment (but not limited thereto), the time frequency of the deviation events E is in the range of 5 to 32 Hz, and of course, according to other embodiments, other time frequency ranges are also possible (depending on the configuration features of the drive unit and the automobile 1). According to a preferred embodiment, the time frequency of the impulsive deviation events E is not a multiple or divisor of the resonant frequency of the drive unit or components of the automobile 1 in order to avoid the generation of excessive mechanical stress which could lead to excessive wear and even breakage.

[0035] According to a possible embodiment, the limiting system 21 estimates the time-frequency range in which abnormal vibrations (generated by the deviation event E) occur and ensures that the time-frequency range in which abnormal vibrations occur does not include the resonant frequencies of the mechanical members of the drivetrain 6 (i.e., the mechanical members elastically and dynamically connected to the internal combustion engine 4 in the entire chain of torque distribution from the internal combustion engine 4 to the drive wheels 3). If the time-frequency range in which abnormal vibrations occur includes the resonant frequencies of the mechanical members of the drivetrain 6, the limiting system 21 modifies the time frequency of the deviation event E (usually a small modification is sufficient) to prevent the time-frequency range in which abnormal vibrations occur from including the resonant frequencies of the mechanical members of the drivetrain 6. According to a possible embodiment, the limiting system 21 uses a mathematical model consisting of equations or maps to calculate the time-frequency range in which abnormal vibrations occur, or the limiting system 21 stores the resonant frequencies of the mechanical members of the drivetrain 6 in appropriate memory.

[0036] According to a possible embodiment, as further safety control in the event of abnormal vibration (generated by deviation event E), the limiting system 21 controls signals from one or more accelerometers (or other vibration sensors) present in the internal combustion engine 4 or other part of the vehicle 1 (e.g., the transmission 7) to ensure that the abnormal vibration (generated by deviation event E) does not correspond to an abnormal vibration peak (which may cause mechanical resonance). If the system 21 detects the presence of an abnormal vibration peak around the abnormal vibration (generated by the deviation event), it modifies the time frequency of the deviation event E (usually a small modification is sufficient).

[0037] As described above, the desired time frequency of deviation event E (and therefore abnormal vibration and noise) is always the same regardless of the rotational speed ω of the drive unit, and naturally, the operation of abnormal event E (which is performed with the desired time frequency as the target) was unable to obtain the desired time frequency precisely (i.e., since it is impossible to perform the control perfectly, the actual time frequency of deviation event E could be slightly different from the desired time frequency of deviation event E).

[0038] If the time frequency of deviation event E is in the range of 5 to 32 Hz, then deviation event E must be activated 5 to 32 times per second. Furthermore, an internal combustion engine 4 with 12 cylinders 11 operating at 6,000 rpm (the drive wheels 3 rarely lose grip when the internal combustion engine 4 is near its minimum rpm) can perform 600 combustion cycles per second and therefore has the potential to perform 600 deviation events E per second. Thus, since 600 combustion cycles per second are available when the engine is operating at 6,000 rpm, it is relatively easy to activate deviation event E such that its actual time frequency is substantially identical to the desired time frequency of deviation event E (e.g., in the range of 5 to 32 Hz).

[0039] According to a possible embodiment, the limiting system 21 determines the degree of slip of the drive wheel 3 and modulates the intensity of abnormal vibration and abnormal noise according to the degree of slip of the drive wheel 3, such that the greater the degree of slip of the drive wheel 3, the stronger the abnormal vibration and abnormal noise.

[0040] For example, the degree of slip of the drive wheel 3 can be measured by the slip S of the drive wheel 3, which is calculated by the following formula. S = (ω3 - ω2) / ω2 ω2 is the rotational speed corresponding to the longitudinal velocity of the vehicle 1 (for example, determined based on the rotational speed of the front driven wheel 2); ω3 Rotational speed of drive wheel 3; S Slip of drive wheel 3.

[0041] As described above, the disparity notification law preferably involves periodically activating an impulsive deviation event E that determines the impulsive gap in the torque generated by the drive unit (i.e., the internal combustion engine 4).

[0042] If the drive unit is an internal combustion engine 4, the impulsive deviation event E consists of a missing (possibly incomplete) fuel injection (technically known as a "cutoff") in at least one single cylinder 11, which determines a missing (possibly incomplete) combustion in cylinder 11, followed by a variable number of normal injections (technically known as "firings") in subsequent cylinders 11 (i.e., cylinders where combustion should occur according to the firing order of the internal combustion engine 4), which determine the normal combustion in the subsequent cylinders 11. By combining the number of missed fuel injections ("cutoff") and normal fuel injections ("firing") in a predetermined order, the intensity and time frequency of abnormal vibration and abnormal noise are generated, and in order to obtain a high time frequency of impulsive deviation event E (and therefore a high time frequency of abnormal vibration and abnormal noise), a missed fuel injection is performed in one single cylinder 11 (to completely omit combustion in this cylinder 11), followed by a small number of normal injections in subsequent cylinders 11, while in order to obtain a lower time frequency of impulsive deviation event E (and therefore a lower time frequency of abnormal vibration and abnormal noise), a missed fuel injection is performed in one single cylinder 11 (to completely omit combustion in this cylinder 11), followed by a large number of normal injections in subsequent cylinders 11. To obtain a more intense impulsive deviation event E, the impulsive deviation event E may be a series of missing injections in several cylinders 11, rather than a single cylinder 11; that is, the impulsive deviation event E may be a series of missing injections in one or more cylinders that burn after the first cylinder 11 according to a predetermined firing order, rather than just the first cylinder 11.

[0043] Preferably, since the impulsive deviation event E (i.e., a missing injection in one single cylinder 11) is solely for the purpose of generating a warning to the driver and does not want to significantly "disrupt" the normal, balanced operation of the drive unit, the impulsive deviation event E, i.e., a missing injection in one single cylinder 11 (such as a complete lack of combustion in cylinder 11), is always followed by multiple (at least 15) normal injections in subsequent cylinders 11.

[0044] According to a preferred embodiment, the limiting system 21 ensures that the internal temperature T of the catalytic converter 15 located along the exhaust duct 14 of the internal combustion engine 4 does not rise excessively due to the use of the unbalanced notification law, and if the use causes the internal temperature of the catalytic converter 15 to rise excessively, the limiting system 21 prohibits (from the beginning) or interrupts (after it has started) the use of the unbalanced notification law.

[0045] In practice, slip of the drive wheels 3 generally occurs when the internal combustion engine 4 generates a large torque during transient operation (i.e., when the operating point changes continuously), in which a certain amount of unburned fuel is present (because a rich fuel mixture with an excess of fuel is used to lower the maximum temperature of the cylinder 11), and a series of impulsive deviation events E (i.e., missing fuel injections) resulting from the law of notification due to imbalance bring excess oxygen into the exhaust duct 14, causing immediate and violent combustion of the fuel located in the catalytic converter 15 (with a significant rise in the internal temperature of the catalytic converter 15). To prevent permanent damage to the catalytic converter 15, the internal temperature T of the catalytic converter 15 is set to the maximum safe value T MAX It must never exceed (generally equivalent to approximately 940-960°C).

[0046] According to a possible embodiment, the limiting system 21 estimates the internal temperature T of the catalytic converter 15 located along the exhaust duct 14 of the internal combustion engine 4, and when the internal temperature T of the catalytic converter 15 reaches a guaranteed threshold (maximum safe value T), the limiting system 21 estimates the internal temperature T of the catalytic converter 15. MAXIf it exceeds (appropriately lower than), the use of the disequilibrium notification law is prohibited or suspended. For example, the limiting system 21 can use a mathematical model (consisting of equations or maps) to estimate the internal temperature T of the catalytic converter 15 depending on the operating point and torque reserve of the internal combustion engine 4 (the operating point of the internal combustion engine 4 consists of rotational speed ω and load).

[0047] According to a possible embodiment, the limiting system 21 waits for a pause period, starting from the end of the previous use of the unbalance notification rule, before enabling the next new use of the unbalance notification rule; that is, the unbalance notification rule cannot be used again until a pause period has elapsed after it has been used in the slip of the drive wheel 3 (even if there is slip in the drive wheel 3, no "notification" is given to the driver because maintaining the integrity of the catalytic converter 15 is more important than providing this kind of feedback to the driver).

[0048] The pause time allows for cooling of the catalytic converter 15 and can have both a constant and a variable duration, depending on the duration of the previous use of the law of notification due to imbalance (the longer the previous use of the law of notification due to imbalance, the longer the pause time must be).

[0049] In the embodiments shown in Figures 1, 2, and 3, the internal combustion engine 4 comprises two banks 10, each having (six) cylinders 11, and two control units 18, each associated with the corresponding bank 10, controlling all individual injectors 16 in its own bank 10. Each control unit 18 operates autonomously and completely independently of the other control unit 18, in other words, each control unit 18 (and therefore both the master control unit 18 and the slave control unit 18) implements its own unique notification system 21 (i.e., contains internal software that generates the notification system 21), which is autonomous and completely independent of the notification system 21 of the other control unit 18, and operates separately and completely independently of the notification system 21 of the other control unit 18 (i.e., without exchanging any information).

[0050] Naturally, the two notification systems 21 implemented in the two control units 18 are completely identical, that is, they are identical twin systems.

[0051] Each control unit 18's notification system 21 autonomously, that is, without ever "consulting" with the notification system 21 of the other control unit 18, determines the start and end of the operation of the unbalanced notification rule based solely on the parameter values ​​read in the field bus 19; that is, it autonomously determines when the unbalanced notification rule should be activated and when it should be deactivated. In other words, each control unit 18's notification system 21 completely ignores what (or isn't) the notification system 21 of the other control unit 18 is doing, and simply examines the information available in the field bus 19 to activate the unbalanced notification rule (when the drive wheel 3 begins to slip) and then deactivate it (when the drive wheel 3 stops slipping).

[0052] The hardware (of the two control units 18) is identical, the software (of the two notification systems 21 implemented in the two control units 18) is identical, and the information received from the field bus 19 is exactly the same (because there is one single field bus 19 for the entire vehicle 1). As a result, even if the two notification systems 21 implemented in the two control units 18 never communicate with each other, they both have the same response to the same stimulus at the same time, and therefore operate substantially synchronously in any case. That is, two entities that are completely identical from a hardware and software standpoint (i.e., two notification systems 21 implemented in the two control units 18) respond to the same input (derived from the same field bus 19) with the same behavior and at the same time. Therefore, substantial synchronization of the operation of the two notification systems 21 can be achieved without any form of communication between them.

[0053] In practice, the two control units 18 communicate with each other via the field bus 19, but this is not fast enough to enable proper synchronization of the extremely rapid impulsive deviation events E. Therefore, it is considered impossible to synchronize the operation of the two notification systems 21 using the field bus 19 because the dynamics of the impulsive deviation events E (on the range of a few milliseconds when the rotational speed ω is high) are much faster than the communication delay set by the field bus 19 (on the range of 10 to 20 milliseconds). This limitation of the field bus 19 (the inability to synchronize the operation of the two notification systems 21 using the field bus 19) is completely overcome thanks to the fact that the two notification systems 21 are made completely identical and completely autonomous from each other, that is, both control units 18 (i.e., both the master control unit 18 and the slave control unit 18) operate the notification law due to imbalance in their own bank 10 of the cylinder 11 autonomously and completely independently of the other control unit 18. In other words, by having the two control units 18 operate the imbalance-based notification rule independently, rapid synchronization via the field bus 19 is no longer necessary, and as a result, the "timing" problem caused by the insufficient communication speed of the field bus 19 is avoided.

[0054] In summary, the two notification systems 21 implemented in the two master and slave control units 18 independently set the start (and end) of the unbalanced notification rule in response to the presence of slip in the drive wheels 3 (confirmed based on information read in the field BUS 19), and the two notification systems 21 implemented in the two master and slave control units 18 can start the unbalanced notification rule in operation at substantially the same moment because both control units are controlled in parallel and the operating conditions are identical for both control units.

[0055] The intervention of the two notification systems 21 may depend not only on the loss of traction of at least one drive wheel 3, but also on other conditions, that is, the notification system 21 may only intervene (i.e., activate the disequilibrium notification law) if the loss of traction of at least one drive wheel 3 occurs in conjunction with other events. For example, the notification system 21 may only intervene (i.e., activate the disequilibrium notification law) if the loss of traction of at least one drive wheel 3 occurs in conjunction with a non-zero steering angle of the front wheels 2 (i.e., only if the vehicle 1 is traveling along a curve), and indeed, slip of a drive wheel 3 has no particular adverse effect (except for a decrease in performance) when traveling along a straight path, but slip of a drive wheel 3 in a curve can cause power oversteer that may lead to a 180° spin. For example, the notification system 21 may intervene (i.e., activate the notification rule due to imbalance) only when the accelerator pedal has moved beyond a given position (i.e., has been pressed hard by the driver). For example, the notification system 21 may intervene (i.e., activate the notification rule due to imbalance) only when the rotational speed ω of the internal combustion engine 4 exceeds a given threshold.

[0056] Normally, there is an exchange of messages between the two control units 18 via the field bus 19 (for example, the accelerator pedal position signal is controlled by a single master control unit 18 and needs to be transmitted to the slave control unit 18 via the field bus 19, i.e., the master control unit 18 makes the accelerator pedal position signal available on the field bus 19), and if the signal generated by the master control unit 18 and made available on the field bus 19 is part of the determination of the start (stop) of the operation of the imbalance notification rule (for example, the accelerator pedal position signal), the notification system 21 implemented in the master control unit 18 applies a standard predetermined time delay to this signal that is equal to the communication time delay of this signal on the field bus 19, so that the time conditions are the same as those of the notification system 21 implemented in the slave control unit 18. In other words, if the master control unit 18 processes control parameters that it exposes to field bus 19, which are read by the slave control unit 18 and used by both control units 18 to determine the start or end of the notification rule's operation, the master control unit 18 applies a time delay to the control parameters equal to the communication time delay in field bus 19 when it uses the control parameters to determine the start or end of the notification rule's operation (in this way, it puts itself on the same conditions as the slave control unit 18).

[0057] The notification system 21 operates independently for both banks 10, so that incomplete or missing fuel injections (i.e., impulsive deviation events E) occur alternately in the cylinders 11 of the two banks 10, and thus prevent all incomplete or missing fuel injections from occurring in the cylinders 11 of the same bank 10, thus preventing excessive overheating of the catalytic converter 15 in the corresponding exhaust duct 14 and / or abnormal mechanical stress on the crank mechanism and mechanical connecting members.

[0058] According to a possible embodiment, two notification systems 21 (identical to each other, i.e., using the same algorithm) operate at the same timing and therefore always (naturally, taking into account a predetermined firing order) trigger the same incomplete or missing fuel injection (i.e., the same impulsive deviation event E) in both banks 10 at substantially the same moment, i.e., when an incomplete or missing fuel injection occurs in a cylinder 11 of bank 10, the same incomplete or missing fuel injection also occurs in a cylinder 11 of the other bank 10 that is “fired” immediately afterward (based on a predetermined firing order), which is the possibility of an action that results in a greater notification intensity (always causing incomplete or missing fuel injections in two cylinders 11 that are “fired” consecutively in a predetermined firing order).

[0059] According to the alternative embodiment, the two notification systems 21 (identical to each other, i.e., using the same algorithm) operate at different timings, i.e., notification system 21 operates at different timings to the other notification system 21 such that an incomplete or missing fuel injection in a cylinder 11 of bank 10 is always followed by a given number of normal injections in the cylinders 11 of both banks 10 (according to a predetermined firing order), i.e., there is an incomplete or missing fuel injection in a cylinder 11 of the other bank 10 between two incomplete or missing fuel injections in a cylinder 11 of bank 10 (in particular, the incomplete or missing fuel injection in a cylinder 11 of bank 10 is substantially midway between two incomplete or missing fuel injections in a cylinder 11 of the other bank 10).

[0060] If the time frequency of an impulsive deviation event E (i.e., an incomplete or missing fuel injection in at least one cylinder 11) must be kept (approximately) constant (even when the rotational speed ω of the drive unit changes), each notification system 21 determines, based on the desired time frequency of the impulsive deviation event E and the rotational speed ω of the drive unit, the number of normal ignitions that must occur between an impulsive deviation event E (i.e., an incomplete or missing fuel injection in at least one cylinder 11) and a subsequent impulsive deviation event E.

[0061] If the two notification systems 21 operate at the same time, each notification system 21 will activate a first impulsive deviation event (i.e., an incomplete or missing fuel injection in at least one cylinder 11 of its own bank 10) without delay (i.e., substantially instantaneously, without any delay, i.e., as quickly as possible), and will repeat the impulsive deviation event E (i.e., an incomplete or missing fuel injection in at least one cylinder 11 of its own bank 10) at the same time frequency as the desired time frequency of the impulsive deviation event E, and if the desired time frequency of the impulsive deviation event E must be kept constant, it should be noted that the same desired time frequency will be converted into more ignitions when the rotational speed ω of the internal combustion engine 4 is higher, and into fewer ignitions when the rotational speed ω of the internal combustion engine 4 is lower. As a result, the two notification systems 21 operate together at the same time, and therefore the two impulsive deviation events E generated by the two notification systems 21 are consecutive and are therefore perceived as a single impulsive deviation event E having a greater (twice as) intensity occurring at a desired time frequency.

[0062] If the two notification systems 21 operate at different timings, it should be noted that if the notification system 21 (for example, the one implemented in the master control unit 18) activates a first impulsive deviation event (i.e., an incomplete or missing fuel injection in at least one cylinder 11 of its own bank 10) without delay (i.e., substantially instantaneously, without any delay, i.e., as quickly as possible), and repeats the impulsive deviation event E (i.e., an incomplete or missing fuel injection in at least one cylinder 11 of its own bank 10) at half the desired time frequency of the impulsive deviation event E, and if the desired time frequency of the impulsive deviation event E must be kept constant, then the same desired frequency will be converted into more ignitions when the rotational speed ω of the internal combustion engine 4 is higher, and into fewer ignitions when the rotational speed ω of the internal combustion engine 4 is lower. On the other hand, the other notification system 21 (implemented, for example, in the slave control unit 18) activates a first impulsive deviation event (i.e., an incomplete or missing fuel injection in at least one cylinder 11 of its own bank 10) with a delay corresponding to a desired time frequency of the impulsive deviation event E, and repeats the impulsive deviation event E (i.e., an incomplete or missing fuel injection in at least one cylinder 11 of its own bank 10) at a time frequency half the desired time frequency of the impulsive deviation event E, and it should be noted that if the desired time frequency of the impulsive deviation event E must be kept constant, the same desired time frequency is converted into more ignitions when the rotational speed ω of the internal combustion engine 4 is higher, and into fewer ignitions when the rotational speed ω of the internal combustion engine 4 is lower. As a result, the two notification systems 21 operate at different timings, and the time difference is equal to the desired time frequency of the impulsive deviation event E, so that, overall, there is an impulsive deviation event E that occurs at the exact desired time frequency of the impulsive deviation event E (or, if an impulsive deviation event E is activated in the right bank 10, subsequent impulsive deviation events E will be activated in the left bank 10).

[0063] The following describes numerical examples of how the notification rules operate due to imbalances in both cases: when the two notification systems 21 operate at the same time and when the two notification systems 21 operate at different times.

[0064] Referring to the cylinder numbers 11 shown in Figure 4, the firing order of the 12 cylinders 11 in the two banks 10 may be "1-7-5-11-3-9-6-12-2-8-4-10" (i.e., alternating firing of the cylinders 11 in the two banks 10). However, this is, of course, only one example of a firing order for the 12 cylinders 11, and other firing orders are also possible.

[0065] Because the drive wheel 3 has lost grip, the law of notification due to imbalance must be activated. Assuming the desired time frequency of the impulsive deviation event is 25 Hz and the rotational speed ω of the internal combustion engine 4 is 3000 rpm (equal to 50 rpm), then the impulsive deviation event E must occur 25 times per second. Every two full rotations of the drive shaft, ignition normally occurs in all 12 cylinders 11. Therefore, at 50 rpm, there are a total of 300 ignitions per second in the 12 cylinders 11 (under normal conditions, i.e., without impulsive deviation event E). To make the desired time frequency of the impulsive deviation event E equal to 25 Hz, the impulsive deviation event E must be activated every 12 theoretical ignitions (i.e., those that would occur under normal conditions where the law of notification due to imbalance is not activated) in all 12 cylinders 11.

[0066] According to a possible embodiment, the two notification systems 21 operate at the same time and therefore, when the notification rule due to imbalance must be activated, the notification system 21 implemented in the right-hand control unit 18 immediately executes an impulsive deviation event E, for example, due to a missing or incomplete fuel injection in cylinder 11 number "1", followed by a normal fuel injection in the other cylinders 11 numbered "5-3-6-2-4", then another missing or incomplete fuel injection in cylinder 11 number "1", followed by a normal fuel injection in the other cylinders 11 numbered "5-3-6-2-4", and so on, thereby activating the notification rule due to imbalance. If action is required, the notification system 21 implemented in the left control unit 18 immediately executes an impulsive deviation event E due to a missing or incomplete fuel injection in cylinder 11 number "7", followed by normal fuel injection in the other cylinders 11 numbered "11-9-12-8-10", then another missing or incomplete fuel injection in cylinder 11 number "7", followed by normal fuel injection in the other cylinders 11 numbered "11-9-12-8-10", and so on (it should be noted that all of this is done without any kind of communication between the two notification systems 21 implemented in the two control units 18).

[0067] In summary, for each of the 12 theoretical ignitions in all 12 cylinders 11 (i.e., those that would occur under normal conditions where the law of notification due to imbalance is not in operation), there is one single impulsive deviation event E (consisting of missing or incomplete fuel injections in two cylinders 11 of the two banks 10 that are ignited in succession).

[0068] According to another embodiment, if two notification systems 21 operate at different timings and therefore must activate the notification rule due to imbalance, the notification system 21 implemented in the right control unit 18 (which may be the master control unit 18) immediately executes an impulsive deviation event E, for example, due to a missing or incomplete fuel injection in cylinder 11 number "1", followed by normal fuel injections in the other cylinders 11 numbered "5-3-6-2-4" and all cylinders 11 of the right bank 10 (i.e., all cylinders "1-5-3-6-2-4"), then again a missing or incomplete fuel injection in cylinder 11 number "1", followed by normal fuel injections in the other cylinders 11 numbered "5-3-6-2-4", and so on, and on the other hand, due to imbalance If a notification rule must be activated, the notification system 21 implemented in the left control unit 18 (which may be a slave control unit 18) applies a time delay and therefore immediately performs normal fuel injection in all cylinders 11 of the left bank 10 (i.e., all cylinders "7-11-9-12-8-10"), followed by a missing or incomplete fuel injection in cylinder 11 number "7", then normal fuel injection in the other cylinders 11 number "11-9-12-8-10", then normal fuel injection again in all cylinders 11 of the left bank 10 (i.e., all cylinders "7-11-9-12-8-10"), and so on (it should be noted that all of this is done without any kind of communication between the two notification systems 21 implemented in the two control units 18).

[0069] In summary, for each of the 12 theoretical ignitions in all 12 cylinders 11 (i.e., those that are expected to occur under normal conditions where the law of notification due to imbalance is not in effect), there is one single impulsive deviation event E (consisting of a missing or incomplete fuel injection, the first occurring in cylinder 11 of the left bank 10, and the next in cylinder 11 of the right bank 10).

[0070] Figure 5 shows the time evolution of the rotational speed ω of the internal combustion engine 4 and the internal temperature T of the catalytic converter 15 when the notification law due to imbalance is activated. Note the increase in the internal temperature T of the catalytic converter 15 corresponding to a series of impulsive deviation events (i.e., incomplete or missing fuel injections) with a constant time frequency even as the rotational speed ω of the internal combustion engine 4 increases, and a series of impulsive deviation events E.

[0071] In the embodiments shown in Figure 1, Figure 2, or Figure 3, the drive unit of the automobile 1 is an internal combustion engine 4, and therefore the impulsive deviation event of the notification law due to imbalance is an incomplete or missing fuel injection in a single cylinder 11.

[0072] In the embodiments shown in Figures 6 and 7, the drive unit of the automobile 1 consists of two electric motors 22, each connected to a corresponding rear drive wheel 3 by a mechanical drive system 23 (e.g., comprising a planetary gear system). Each electric motor 22 is controlled by a corresponding electronic power converter 24 that supplies AC voltage to a corresponding stator winding 25 (Schematically shown in Figure 7). In this embodiment, an impulsive deviation event E may be an unbalanced power supply (naturally, for a very short time) to the stator winding 25, for example, by distorting the supply to one phase from the supply to the other phase.

[0073] The operation of the notification law due to imbalance generally causes periodic operational irregularities that generate both driver-perceptible abnormal (i.e., normally absent) vibrations and driver-perceptible abnormal (i.e., normally absent) noises. However, according to other embodiments, the operation of the notification law due to imbalance generally causes periodic operational irregularities that generate either driver-perceptible abnormal (i.e., normally absent) vibrations only, or driver-perceptible abnormal (i.e., normally absent) noises only.

[0074] It should be noted that the vibration and acoustic feedback transmitted to the driver in the event of drive wheel 3 slippage can generally be activated and deactivated by the driver depending on the type of driving. In fact, this type of vibration and acoustic feedback in the event of drive wheel 3 slippage is extremely useful and valuable in high-performance driving on a circuit, but it is not as useful in everyday driving on open roads where drive wheel 3 slippage is extremely rare and caused by localized poor road surface conditions.

[0075] In the embodiment shown in the attached drawings, the control method is applied to automobile 1, but according to other embodiments not shown herein, the control method is applied to different types of road vehicles, such as mopeds, motorcycles, vans, trucks, or buses.

[0076] The embodiments described herein can be combined with one another, and such combinations will not result in the exclusion of the scope of protection of the present invention.

[0077] The control method described above has various advantages.

[0078] Firstly, the control method described above provides the driver with extremely clear and perceptible feedback (i.e., no possibility of the driver ignoring it or mistaking it for something else) regarding the slip of the drive wheels 3 (i.e., any possible traction control intervention), and at the same time, it is extremely "pleasant" (i.e., perfectly matches what the driver's emotional side expects from their car 1). In this regard, it should be noted that high-performance sports cars are fundamentally valued for the extreme enjoyment they can provide, and one of the main aspects to consider when defining what makes a car fun is the car's behavior in controlled slip. The control method described above enhances the "driving enjoyment" of car 1 by providing vibration feedback to the steering wheel and acoustic feedback from the exhaust, under conditions where the internal combustion engine 4 is normally controlled in a "silent" ("lively") manner. In fact, the driving "feeling" that can be reproduced thanks to the control method described above is the driving feel of the traction control of Formula 1 prototypes from the early 2000s, which is always highly valued by enthusiasts of high-performance sports cars.

[0079] Furthermore, the control method described above is extremely flexible and therefore allows for adjustment of abnormal vibrations and noises generated in the event of loss of grip of the drive wheels 3 to the driver's preference. Moreover, the control method described above allows for adjustment of abnormal vibrations and noises generated in the event of loss of grip of the drive wheels 3 based on the degree of loss of grip (i.e., the greater the loss of grip, the greater the intensity and time-frequency of the abnormal vibrations and noise), thus enabling the driver to be notified of the loss of grip not only qualitatively but also quantitatively.

[0080] The method described above can be easily implemented even in the presence of an internal combustion engine 4 having two banks 10 of cylinders 11 controlled by two independent control units 18, by efficiently and effectively overcoming the limitations of the speed of communication between the control units 18 via the field bus 19.

[0081] Finally, the control method described above can be implemented very easily and economically in existing vehicles because it does not require the installation of additional hardware to be added to the hardware already available in modern vehicles, high processing power for the traction control system 20's processor, or large space in the traction control system 20's memory. [Explanation of Symbols]

[0082] 1. Automobile 2 Front wheels 3 Rear wheels 4 organizations 5. Drive shaft 6. Drivetrain 7. Transmission 8. Transmission shaft 9 Differential device 10 Bank 11 cylinders 12 Intake Manifold 13 Exhaust manifold 14 Exhaust duct 15 Exhaust gas treatment device 16 Injectors 17 Control Systems 18 Control Unit 19 Field Bus 20. Traction control system 21 Notification System 22 Electric motor 23 Mechanical drive system 24 Electronic Power Converters 25 Stator winding ω rotation speed T temperature T MAX Maximum safety value E Deviation Event t time

Claims

1. In order to control a road vehicle (1) when the drive wheels (3) rotated by the engine slip, Steps include detecting slippage of at least one drive wheel (3), A step of controlling the engine by an unbalanced notification law in order to obtain periodic operational irregularities that produce abnormal vibrations and / or abnormal noises perceptible to the driver only when at least one drive wheel (3) slips, A method that includes, A further step is to keep the desired time frequency of the abnormal vibration and / or abnormal noise substantially constant, even when the rotational speed (ω) of the engine changes, and A further step of activating the disparity notification law, which has a target constant desired time frequency, even when the rotational speed (ω) of the engine changes. A control method characterized by including

2. The control method according to claim 1, wherein the notification rule involves periodically activating an impulsive deviation event (E), the impulsive deviation event (E) causing the abnormal vibration and / or the abnormal noise, and having a constant desired time frequency which is a divisor of the desired time frequency of the abnormal vibration and / or the abnormal noise.

3. The control method according to claim 2, wherein the desired time frequency of the deviation event (E) is in the range of 5 to 32 Hz.

4. The control method according to claim 2 or 3, wherein the desired time frequency of the abnormal vibration is not a multiple or divisor of the resonant frequency of the engine or the components of the road vehicle (1).

5. A further step of checking in advance whether the desired time frequency may cause resonance in the engine or components of the road vehicle (1), To ensure that the desired time frequency of the abnormal vibration does not cause resonance in the engine or components of the road vehicle (1), a further step is to modify the desired time frequency of the notification rule. A control method according to any one of claims 2 to 4, including the method described in any one of claims 2 to 4.

6. A further step is to determine the desired torque required by the driver of the aforementioned road vehicle (1): A further step of controlling the engine to generate a normal torque equal to the desired torque when there is no slippage of the drive wheel (3), and A further step of controlling the engine to generate a reduced torque, i.e., a torque smaller than the desired torque, only when at least one drive wheel (3) is slipping. A control method according to any one of claims 1 to 5, including the method described in any one of claims 1 to 5.

7. The control method according to claim 6, wherein, only when at least one drive wheel (3) slips, the reduction in torque generated by the engine with respect to the desired torque acts on the engine, ensuring the normal balanced operation of the engine and obtained by limiting operation independent of the notified law.

8. The control method according to claim 7, wherein the engine is controlled by the notification rule, which is independent of the limiting action and applied autonomously to the limiting action, only when at least one drive wheel (3) is slipping, and simultaneously with a reduction in the torque generated by the engine, causing the engine to operate in an abnormal manner and generating abnormal vibration and / or abnormal noise that is perceptible to the driver.

9. The control method according to any one of claims 1 to 8, wherein the notification rule involves periodically activating an impulsive deviation event (E) that determines an impulsive gap in the torque generated by the engine.

10. The engine comprises an internal combustion engine (4) which is provided with a plurality of cylinders (11) and a plurality of fuel injectors (16) each that inject fuel into the corresponding cylinder (11). The control method according to claim 9, wherein the impulsive deviation event (E) consists of at least one incomplete injection or lack of injection of fuel into a single cylinder (11) that determines incomplete combustion or lack of combustion in the cylinder (11), followed by a plurality of normal injections in subsequent cylinders (11) in the ignition sequence.

11. The control method according to claim 10, wherein the impulsive deviation event (E) consists of at least one incomplete injection or lack of injection of fuel to a single cylinder (11) that determines incomplete combustion or lack of combustion in the cylinder (11), followed by at least 15 normal injections in subsequent cylinders (11) in the ignition sequence.

Images