Management of acceleration and deceleration of a vehicle

Abstract

The invention relates to a method for controlling the acceleration of a vehicle (1) comprising a powertrain (3) that receives, from a control unit, an acceleration setpoint defined by a function (2) for managing the deceleration and / or the acceleration of a vehicle, and at least one advanced driver assistance system including at least a speed limiting function and / or a cruise control function, wherein the method of the vehicle (1) is implemented in such a way that, when the cruise control function (6) and / or the limiting function (7) is deactivated, a parameterisable jerk (8) is generated on the acceleration setpoint.

Description

DESCRIPTION TITLE: MANAGING VEHICLE ACCELERATION AND DECELERATION The present invention claims priority from French application No. 2413863 filed on December 11, 2024, the content of which (text, drawings and claims) is incorporated herein by reference. TECHNICAL FIELD OF THE INVENTION

[0001] The invention relates, in general, to the technical field of advanced driver assistance systems, commonly known as ADAS, for example, for autonomous or semi-autonomous vehicles. ADAS encompasses a set of technologies enabling the partial automation of certain driving tasks, such as controlling a vehicle's acceleration and deceleration to influence its speed. These tasks rely on means of controlling the vehicle's acceleration to maintain it at a chosen speed and / or avoid a collision with another vehicle in front by maintaining a predefined safety distance.

[0002] The invention relates more specifically to the control of acceleration when the speed limitation or regulation functions are deactivated.

[0003] The invention applies to all types of vehicles equipped with active driver assistance systems (such as level 1 driver assistance vehicles), semi-autonomous vehicles (such as level 2 driver assistance vehicles), autonomous vehicles (such as level 3 and 4 driver assistance vehicles), or fully autonomous vehicles (such as level 5 driver assistance vehicles). PREVIOUS STATE OF THE ART

[0004] In a known type of vehicle, an onboard system for autonomous vehicles, when cruise control is deactivated, requests torque from a component of the vehicle's powertrain (PMU) to limit the vehicle's acceleration and reduce its deceleration to a threshold value. When deceleration becomes excessive, a control unit increases engine torque. to reduce deceleration below a certain threshold. Simultaneously, this system compares the acceleration induced by the deactivation of the cruise control to a high threshold and a low threshold. If the acceleration induced by the deactivation of the cruise control does not exceed either threshold, then the system does not intervene. However, if the acceleration induced by the deactivation of the cruise control exceeds either threshold, the system activates and requests an increase in torque if the low threshold is exceeded, or a reduction in torque if the high threshold is exceeded.

[0005] When a driver deactivates a cruise control or speed limiter function, the acceleration command will change from a value sufficient to maintain the target speed to a fallback value in one calculation step, meaning almost instantaneously. This deactivation of the cruise control or speed limiter function will shift the torque command from a low value (sufficient to maintain a constant vehicle speed) to a fallback value dependent on the driver's accelerator pedal depressor. This results in a sudden acceleration of the vehicle. This abrupt change in the car's acceleration when the driver deactivates the cruise control or speed limiter function can be surprising and cause an unpleasant sensation while driving.

[0006] Therefore, there is a need for a solution that allows continuous and progressive control of acceleration when a vehicle's speed regulation or limitation function is deactivated, in order to avoid sudden acceleration of said vehicle. DESCRIPTION OF THE INVENTION

[0007] The invention aims to remedy all or part of the drawbacks of the prior art by proposing a method and an on-board device for controlling acceleration when the speed limitation and / or regulation functions are deactivated.

[0008] According to a first embodiment of the invention, a method is proposed for controlling the acceleration of a vehicle comprising a powertrain receiving an acceleration command defined by a function of vehicle deceleration and / or acceleration management by a control unit, and at least one advanced driver assistance system including at least one speed limitation and / or speed regulation function for said vehicle which can be activated, characterized in that when said speed limitation and / or speed regulation function is deactivated, a configurable jerk is generated on said acceleration command.

[0009] According to a preferred embodiment, the configurable jerk is capable of ensuring a gradual transition of the acceleration setpoint. This gradual transition is between a first value defined by the speed limiting and / or regulation function and a fallback value when said speed limiting and / or regulation functions are deactivated.

[0010] Advantageously, said deceleration and / or acceleration management function controls the acceleration requested by a driver when the speed limitation and / or regulation functions are deactivated, which defines said fallback value of the acceleration setpoint when said speed limitation and / or regulation functions are deactivated.

[0011] Preferably, the deactivation of said speed limitation and / or speed regulation functions is carried out via a dial, control buttons on the vehicle's steering wheel and / or the brake pedal and / or the clutch pedal.

[0012] Advantageously, the acceleration command defines a torque command to be delivered by said powertrain to achieve the acceleration of said vehicle requested by said driver or said speed limitation and / or regulation functions when activated.

[0013] According to a second aspect of the invention, a computer program product is proposed comprising code instructions recorded on a computer-readable medium for the implementation of the process as defined above.

[0014] According to a third aspect of the invention, a device for controlling the deceleration and / or acceleration of a vehicle is proposed, capable of generating, when a speed limitation and / or regulation function of said vehicle is deactivated, a jerk configurable on an acceleration setpoint between a value defined by said speed limitation and / or regulation function and a fallback value in order to ensure a progressive transition of a torque delivered by a powertrain of said vehicle according to said acceleration setpoint.

[0015] According to a fourth aspect of the invention, a vehicle is proposed comprising a powertrain delivering torque to generate acceleration of said vehicle, a control unit sending an acceleration command to said powertrain defined by a deceleration and / or acceleration management function of said vehicle, and at least one advanced driver assistance system including at least one speed limiting and / or speed control function of said vehicle. In which, said deceleration and / or acceleration management function implements a method for controlling acceleration when the speed limiting and / or speed control functions, as described above, are deactivated. BRIEF DESCRIPTION OF THE FIGURES

[0016] The description refers to the attached figures, which are also given as non-limiting examples of embodiments of the invention:

[0017] [Fig. 1] Figure 1 shows a top view of a vehicle equipped with an acceleration and deceleration management system linked to a GMP.

[0018] [Fig.2] Figure 2 presents a schematic representation of the device of the invention.

[0019] [Fig. 3] Figure 3 shows a representation of the acceleration and deceleration management system DETAILED DESCRIPTION OF A METHOD OF IMPLEMENTATION

[0020] There are various technologies and systems that contribute to advanced driver assistance that can be used to regulate or limit the speed of a vehicle. Adaptive cruise control (ACC) adjusts a vehicle's speed to maintain a safe distance from the vehicle in front. ACC can also maintain a speed set by the driver and, optionally, prevent exceeding a speed limit detected by road analysis or set by the driver.

[0021] Primarily, the deactivation of cruise control and speed limiter systems is done manually following a decision by the driver while driving. When the driver decides to deactivate the cruise control and / or speed limiter function, the acceleration and deceleration management system deactivates, and consequently, the acceleration command it generates also disappears. As a result, the torque command sent to the vehicle's powertrain will change from the value induced by the acceleration command generated by the acceleration and deceleration management system to a fallback value.

[0022] This fallback value is integrated into a coordination function with the torque induced by the driver's input, based on the accelerator pedal depressed, before being sent to the powertrain (PMU) 3 to generate the necessary wheel torque. When the acceleration and deceleration management system 2 is deactivated, the torque command transmitted to the PMU 3 corresponds to the driver's input at the time of deactivation. The transition between these two torque commands, which is not gradual but occurs in a single calculation step, results in a sudden change in wheel torque. This torque jump is a source of discomfort for the driver, as it causes a sudden change in acceleration that is felt throughout the vehicle.

[0023] Figure 1 illustrates a vehicle 1 seen from above equipped with an acceleration and deceleration management system 2 linked to a GMP 3. This vehicle 1 is also capable of implementing an acceleration control method when the speed limitation and / or regulation functions are deactivated, as described below.

[0024] For the acceleration control process to be engaged, it is essential that the cruise control (hereafter referred to as RVV) 4 and / or the speed limiter (hereafter referred to as LVV) 5 be activated beforehand. Indeed, this process of acceleration control can only be performed when RVV 6 is deactivated and / or of LVV 7. The deactivation of RVV 6 and / or LVV 7 can be carried out via a dial, control buttons on the steering wheel of vehicle 1, a brake pedal and / or a clutch pedal.

[0025] Deactivating RW 6 and / or LW 7 sends information to the acceleration and deceleration management system 2. Therefore, when they are deactivated, the acceleration setpoint of the acceleration and deceleration management system 2 will change almost instantaneously from a value capable of guaranteeing the speed setpoint to a fallback value in one calculation step. This deactivation will thus shift the torque setpoint from a low value to a higher fallback value, resulting in a sudden acceleration of the vehicle. To avoid this abrupt change in acceleration, when the acceleration and deceleration management system 2 is deactivated, a configurable jerk 8 is generated on the acceleration setpoint between the value defined by the RW and / or LW function and the fallback value to ensure a gradual transition of acceleration.Jerk refers to the vehicle's acceleration ramp used to make this gradual transition smoothly. Jerk is expressed in m / s. 3 because we are trying to calibrate an acceleration (m / s 2 ) as a function of time (s) or m / s 2 / s, so ultimately m / s 3 .

[0026] The GMP 3 refers to a set of components in a vehicle that generates and transmits the power necessary to move the vehicle. For example, the engine, the gearbox, and the system for transmitting engine torque to the drive wheels of vehicle 1.

[0027] Engine torque is produced by the powertrain (GMP 3) to accelerate vehicle 1. The higher the engine torque, the greater the acceleration of vehicle 1, which can be useful in demanding conditions. Conversely, insufficient engine torque can lead to difficulties, for example, when starting on a hill or during overtaking maneuvers. Engine torque is essential for determining the available power to move and accelerate a vehicle. In this case, controlling acceleration therefore requires a torque command. appropriate to the situation, here the configurable jerk 8 has an effect on the acceleration command and therefore on the resulting engine torque, which is what makes it possible to avoid a sudden unwanted and uncontrolled acceleration.

[0028] Finally, the GMP 3 of vehicle 1 receives a torque command, for example provided by a control unit integrated into the vehicle, following the generation of the configurable jerk 8 allowing it to adjust the engine torque produced by the GMP 3 and transmitted to the wheels and to stabilize the driving.

[0029] Figure 2 illustrates an example of the implementation of the acceleration control process when the RW and / or LW functions are deactivated. This example of the process implementation is illustrated as a series of steps allowing an acceleration and torque setpoint to be transmitted to the GMP 3 in order to have a gradual transition of acceleration.

[0030] Firstly, the method of the invention applies in the case where the vehicle 1 includes a GMP 3 capable of receiving an acceleration command defined by a vehicle deceleration and / or acceleration management function implemented by a control unit, and at least one advanced driving assistance system including at least one LVV and / or RVV function.

[0031] The process is initiated by activating the RW 4 and / or LW 5 function. There are several ways to activate the RW and / or LW function, such as manually activating it using the vehicle's controls, a dial, and / or buttons. Another way to activate the RW and / or LW function is through an advanced driver assistance system, which, if activated beforehand, can automatically adjust the speed based on various parameters such as traffic conditions, road sign recognition, and / or GPS data provided by the vehicle.

[0032] The second step involves the driver deactivating RW 6 and / or LW 7. These functions can be deactivated via a wheel, control buttons on the steering wheel of said vehicle 1, brake pedal and / or clutch pedal.

[0033] The third step involves transmitting the deactivation information for RW 6 and / or LW 7 to the acceleration and deceleration management system 2. When the acceleration and deceleration management system 2 is active, it generates an acceleration command. This acceleration command is transmitted to the powertrain to produce a braking or acceleration torque to counteract external forces acting on the vehicle, for example, when the vehicle is going downhill, accelerating or braking it. Conventionally, when the driver deactivates the RW 6 and / or LW 7 function, the acceleration and deceleration management system 2 also deactivates, and the system's acceleration command changes from a value capable of maintaining speed to a fallback value almost instantaneously.As a result, this deactivation of the RW and / or LW function causes the engine torque to switch from a low value, sufficient to maintain the vehicle's speed constant, to a fallback value, which causes a sudden acceleration of the vehicle.

[0034] This abrupt change in the acceleration of vehicle 1 when the acceleration and deceleration management system 2 is deactivated is very noticeable in certain cases such as during a steep descent and / or when transporting a large mass in vehicle 1. To avoid this disturbing effect for the driver of vehicle 1, when deactivating the RW and / or LW, instead of simply also deactivating the acceleration and / or deceleration system 2, an acceleration control procedure is put in place.

[0035] The fourth step involves applying a configurable jerk 8 when the acceleration and deceleration management system 2 is deactivated. In mechanics, jerk literally corresponds to a jolt, a jolt, that is, a sudden change in the acceleration vector. Jerk is expressed in meters per second cubed. A high jerk corresponds to a rapid change in acceleration, which, as explained above, results in uncomfortable sensations for the driver. In the long term, jerk can cause mechanical stress on the vehicle as well as undesirable variations in its movements. During these sudden variations of The acceleration, and the resulting jerk, can have a negative impact on the vehicle's mechanical components, generating forces on the powertrain which over time can lead to premature wear of its mechanical parts.

[0036] According to the invention, in the acceleration control method, after deactivation of the acceleration and deceleration management system 2, a configurable jerk 8 is applied to the acceleration setpoint generated by the acceleration and deceleration management system 2 in order to avoid a sudden acceleration jump and avoid any discomfort for the driver.

[0037] The final step, 9, involves transmitting the acceleration command to the GMP 3 of vehicle 1. Applying a configurable jerk in step 8 ensures a gradual transition of the acceleration command between an initial value defined by the LVV and / or RVV functions and a fallback value. This allows for the maintenance of torque control after the acceleration and deceleration management system of vehicle 2 is switched off, in order to achieve a torque ramp and thus obtain a gradual cut-off of the brake or engine torque of the acceleration and deceleration management system.

[0038] Thus, a control unit continues to send an acceleration command to the GMP 3 which is defined by the vehicle acceleration and deceleration management system 1 when it is deactivated.

[0039] Figure 3 shows the operation of the acceleration and deceleration management system of vehicle 1 when RW 6 and / or LW 7 are deactivated.

[0040] The first diagram at the top of the figure corresponds to the change of state of the acceleration and deceleration management system 2 when the cutting off of a function RW 6 and / or LW 7 is requested 10.

[0041] Below, the second diagram corresponds to the change of state of the acceleration and deceleration management system 2 when the RW 6 and / or LW 7 function is cut off with the application of a configurable jerk 8 allowing continuous and progressive control of the acceleration.

[0042] The third diagram corresponds to maintaining 11 the control of the acceleration and deceleration management system 2 to perform a configurable jerk 8 when the system is deactivated to follow the cut-off of RVV 6 and / or LVV 7.

[0043] The fourth and penultimate diagram allows visualization and comparison of the acceleration and deceleration management system 2 with or without the application 12 of a configurable jerk 8 at the acceleration level.

[0044] The fifth diagram, at the bottom of the figure, allows visualization and comparison of the result of the acceleration and deceleration management system 2 with or without the application of a parameterizable jerk 8 at the level of the torque delivered 13 by the GMP 3.

[0045] Naturally, the invention described above is by way of example. It is understood that a person skilled in the art is capable of carrying out various embodiments of the invention without departing from the scope of the invention as defined in the claims. For example, the invention described above can be applied to an electric vehicle, that is, one whose movement is powered solely by electrical energy, to a hybrid vehicle whose motive power can be electrical, thermal, or a combination of both, or to a vehicle with an internal combustion engine.

[0046] It is emphasized that all features, as they are apparent to a person skilled in the art from the present description, drawings and claims below, even if in practice they have only been described in relation to other specific features, both individually and in any combinations, can be combined with other features or groups of features disclosed herein, provided that this has not been expressly excluded or that technical circumstances render such combinations impossible or meaningless.

Claims

DEMANDS 1. Method for controlling the acceleration of a vehicle (1) comprising a powertrain (3) receiving an acceleration command defined by a deceleration and / or acceleration management function (2) of a vehicle (1) of a control unit and at least one advanced driver assistance system including at least one speed limitation and / or speed regulation function of said vehicle (1) which can be activated, characterized in that when said speed limitation function (7) and / or said speed regulation function (6) is deactivated, a configurable jerk (8) is generated on said acceleration command.

2. Method for controlling the acceleration of a vehicle (1) according to claim 1, characterized in that said configurable jerk (8) is capable of ensuring a progressive transition of said acceleration setpoint between a first value defined by the speed limitation and / or regulation function and a fallback value when said speed limitation (7) and / or regulation (6) functions are deactivated.

3. Method for controlling the acceleration of a vehicle (1) according to claim 1 or 2, characterized in that said deceleration and / or acceleration management function (2) controls the acceleration requested by a driver when the speed limitation (7) and / or regulation (6) functions are deactivated, which defines said fallback value of the acceleration setpoint when said speed limitation (7) and / or regulation (6) functions are deactivated.

4. Method of controlling the acceleration of a vehicle (1) according to one of the preceding claims, characterized in that the deactivation of said speed limitation (7) and / or speed regulation (6) functions is carried out via a dial, control buttons on the steering wheel of the vehicle (1) and / or the brake pedal and / or a clutch pedal.

5. A method for controlling the acceleration of a vehicle (1) according to any one of the preceding claims, characterized in that the acceleration command defined a torque setpoint to be delivered (9) by said powertrain (3) to achieve the acceleration of said vehicle (1) requested by said driver or said speed limitation (5) and / or regulation (4) functions when activated.

6. Product computer program comprising code instructions recorded on a computer-readable medium for implementing the method of any one of claims 1 to 5.

7. A vehicle 1 deceleration and / or acceleration control device characterized in that it is capable of generating, when a speed limitation function (7) and / or a speed regulation function (6) of said vehicle is deactivated, a configurable jerk (8) on an acceleration setpoint between a value defined by said speed limitation and / or regulation function and a fallback value in order to ensure a progressive transition of a torque delivered by a powertrain (3) of said vehicle (1) according to said acceleration setpoint.

8. Vehicle (1) comprising: a powertrain (3) delivering torque to generate acceleration of said vehicle, a control unit sending an acceleration command to said powertrain (3) defined by a deceleration and / or acceleration management function (2) of said vehicle (1), and at least one advanced driver assistance system including at least one speed limitation and / or speed control function of said vehicle (1), characterized in that said deceleration and / or acceleration management function (2) implements a method for controlling acceleration when the speed limitation (7) and / or speed control (6) functions according to any one of claims 1 to 5 are deactivated.

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