METHOD AND DEVICE FOR REGULATING THE SPEED OF A VEHICLE

Description

technical field

[0001] The present invention relates to methods and devices for regulating vehicle speed, in particular an autonomous vehicle. Technological background

[0002] Some vehicle cruise control systems offer a feature called Intelligent Speed ​​Adaptation (ISA), which is designed to inform the driver as soon as a new speed limit, different from the current set speed used to regulate the vehicle's speed, is detected. The ISA function then suggests a new set speed that is appropriate for this new speed limit. Typically, the new set speed is equal to the new speed limit. This new speed limit is obtained either by reading the new speed limit as the vehicle passes a speed sign, by a camera mounted at the front of the vehicle, from a map database stored in the vehicle, or through transmission via a communication channel.The cruise control commands the display of this proposed set speed change according to a first display mode M1 on an HMI (Human-Machine Interface) such as a screen in vehicle V, for example. As illustrated in the figure. figure 3 , this first display mode may include a display area which shows information presenting the new speed limit (110 km / h), the current set speed of vehicle V, in this case 130 km / h and an interface area offering the driver of vehicle V the opportunity to validate a new set speed equal to the new speed limit, in this case 110 km / h.

[0003] The cruise control either immediately triggers the application of an acceleration or deceleration intended to force the vehicle to travel at the speed defined by the new target speed, or this triggering occurs if the driver validates (accepts) this proposed new target speed by pressing, for example, on a dedicated control device.

[0004] The new speed limit is detected when passing the speed limit sign, and the driver usually takes some time to react before accepting the proposed new speed limit; the vehicle is generally overspeeding after the sign for a distance that depends on its speed at the time of validation.

[0005] The speed limit zone can become problematic when the vehicle is also equipped with a system designed to automatically control its steering (automated vehicle). Indeed, on highways, changes in speed limits are very often linked to variations in the radius of curves, and therefore, if the vehicle is traveling at a speed exceeding the limit, its steering system may be unable to guide it through a turn.

[0006] To address this issue, it has been proposed to generate the new target speed earlier, giving the vehicle time to decelerate or accelerate before the speed limit sign. This is known as AISA, or Anticipated Intelligent Speed ​​Adaptation. AISA requires the vehicle to have sufficient advance notice of the speed limits for the lane it is traveling in.

[0007] The AISA function may only be authorized on roads with specific characteristics. These roads are called "eligible." For simplicity, and for example, we will subsequently consider an eligible road to be a motorway where the speed limit is 130 km / h.

[0008] While the use of the AISA function is certainly safer, it can cause inconvenience to other drivers. As soon as the driver confirms the new set speed, their vehicle may decelerate to that speed and then proceed at this new speed, which is lower than the current speed limit, until the next speed sign, without other drivers being able to understand why. Therefore, depending on the speeds involved and the terrain, the time the vehicle spends at the new speed can range from approximately fifteen to thirty seconds.

[0009] French patent application FR3 034 066 proposes a vehicle speed regulation device that limits as much as possible the inconvenience caused by a change in a vehicle's set speed.This speed regulation device includes processing means arranged, in response to a validation by a vehicle driver of a new limit speed to be respected from a known position and lower than a current set speed, to trigger the establishment of a chosen deceleration profile, designed to decrease the current set speed to a new set speed at most equal to the new limit speed substantially at the known position, between a first position, between a primary position of the vehicle at a time when the driver makes the aforementioned validation and a second position at which the establishment of a maximum deceleration profile can be triggered at the latest, and this second position.A maximum deceleration profile is one in which the vehicle's speed decreases to the maximum, meaning it is rapid enough to minimize the time it takes for the vehicle's speed to decrease from the current set speed to the new set speed, without causing excessive discomfort to passengers. Typically, the maximum deceleration profile is chosen to avoid emergency braking that would be uncomfortable for passengers and dangerous for vehicles traveling behind the vehicle.

[0010] Thus, we are assured that the vehicle is traveling at a speed that complies with the new speed limit at the location of the signpost, that is to say, at the position of the signpost.

[0011] There figure 1illustrates an example of the functioning of the French patent application regulation system FR3 034 066 which implements an AISA function.

[0012] Following the example of the figure 1 , a vehicle V is travelling at 130 km / h on an eligible motorway and is approaching a section of that motorway where the speed limit is 110 km / h.

[0013] According to the AISA function implemented by the aforementioned French patent application, a proposed new setpoint speed adapted to a new speed limit is displayed in a second display mode M2 ​​on an HMI (Human-Machine Interface) such as a screen in vehicle V, for example. As illustrated in the figure 1This second display mode M2 ​​may include a display area showing information including the speed limit of the section currently being traveled by vehicle V (130 km / h), the current set speed of vehicle V, in this case 130 km / h, the new speed limit, in this case 110 km / h, and an interface area offering the driver of vehicle V the option to confirm a new set speed equal to the new speed limit, in this case 110 km / h. This suggestion is displayed at a specific time T, marked on the figure 1indicated by a vertical arrow. At this time T, the control system selects a deceleration profile so that the vehicle travels at the new target speed when it reaches the sign indicating the new speed limit. The time between time T and the new sign depends on the vehicle's actual speed V and the distance between the vehicle and the sign.

[0014] There figure 2 illustrates three deceleration profiles that can be chosen according to the time taken by the driver of vehicle V to validate a proposed change in target speed from time T.

[0015] If the driver accepts the proposal within a reasonable time TR, that is, in relation to the new speed sign, at a time between T and T-TR on the figure 1, vehicle V reaches the new indicator sign with a speed equal to the new target speed (110 km / h) and with maximum comfort (low deceleration).

[0016] If the driver approves the proposal within a longer TC timeframe, i.e., longer than the TR timeframe but shorter than a maximum TT timeframe (TR <TC<TT), la pente du profil de décélération choisi est plus abrupte pour que le véhicule V atteigne le nouveau panneau indicateur avec une vitesse égale à la nouvelle vitesse de consigne (110 km / h). La décélération est alors plus forte mais reste confortable Si le conducteur valide la proposition après une durée TO au-delà de laquelle il ne sera plus possible de décélérer le véhicule V pour qu'il atteigne une vitesse égale à la nouvelle vitesse de consigne au pied du nouveau panneau indicateur, la décélération est maximale et le véhicule V aura une vitesse minimale qu'il est possible d'atteindre au moment du passage du nouveau panneau indicateur. Il finira par atteindre la nouvelle vitesse de consigne mais après que le véhicule sera passé devant le panneau indicateur.The minimum duration TO is generally set at a few seconds and is a function of the difference between the current speed of the vehicle V and the new speed limit.

[0017] The AISA function, as currently implemented, produces a proposed change in setpoint speed at a single time T. However, there are situations where, at that time T, an event may occur that prevents the AISA function from producing a proposed change in setpoint speed.

[0018] The following non-exhaustive list of events that can occur simultaneously or separately is given as an example of situations where a proposal is not produced by the AISA function. the road is not eligible at time T; for a previous sign, a proposal produced by the AISA or ISA function is still in progress; the driver has just changed the target speed just before time T; an automatic lane change (SALC: Semi Automatic Lane Change in English) is engaged or requested around time T.

[0019] These situations can occur quite frequently and severely limit the production of setpoint speed change proposals by the AISA function.

[0020] It is therefore necessary to modify the implementation of the AISA functions to increase the production of setpoint speed change proposals.

[0021] The successive generation of set speed change proposals implies successive displays of these proposals. It is necessary that two successive displays be separated by a minimum duration so that the driver has time to see the first proposal, read it, and act accordingly before the second proposal is displayed to replace the first. A zone, sometimes called a flash zone, is defined to introduce a time interval (TF) between two successive displays of set speed change proposals. This zone is illustrated on the... figure 3 through the hatched area.

[0022] Following the example of the figure 3The AISA function is active until the vehicle reaches the new speed limit sign (110 km / h). The ISA function is then activated. The flashing zone, typically shorter than the minimum duration TO, ensures that two suggestions (one generated by the AISA function and the other by the ISA function) are not generated and displayed too close together. In the example, a first suggestion is generated by the AISA function at time T, outside the time interval TF. This first suggestion is displayed according to the second display mode M2. If this first suggestion is not accepted by the driver CD, a second suggestion is generated by the ISA function once the vehicle has passed the new speed limit sign (110 km / h). This second suggestion is displayed according to the first display mode M1.The flashing zone is an area in which the first proposal is not displayed if the time instant T is within the time interval TF because the driver CD does not then have time to read the information and validate the first proposal (M2) before this first proposal would be erased upon passing the indicator sign and the second proposal (M1) would be displayed (M1).

[0023] We also know from document WO2017 / 008999, a longitudinal guidance driving assistance system in a motor vehicle.

[0024] The problem is to multiply the production of proposals for changing the set speed while respecting the flashing zone. Summary of the present invention

[0025] One object of the present invention is to solve at least one of the problems of the technological background described above.

[0026] Another object of the present invention is to modify the implementation of the AISA function by enabling the generation of a suggested change in the target speed at a time T before passing a speed limit sign, as soon as a set of conditions relating to the vehicle's dynamics and / or environment are met; that is, as soon as the suggested change in the target speed is no longer prevented from being generated due to a situation where such a suggestion cannot be produced by the AISA function. The generated suggestion is then displayed in a second display mode if the time T is outside the time interval TF, and in a first display mode if the time T is within the time interval TF.

[0027] The present invention thus makes it possible to monitor at what time it is possible to generate, by an AISA function, a proposed change in the set speed upstream of a speed limit sign, unlike the current implementation of the AISA function which only allows the generation of a proposal at a fixed (single) time instant, that is, regardless of whether or not this proposal can be generated at that time instant by the AISA function. Furthermore, according to the present invention, the flashing zone is nonexistent because if the proposed change in the set speed is generated during the time interval TF, this proposal is displayed using a display mode also used to display a proposal that would be generated by the ISA function activated from the moment the vehicle passes in front of the speed limit sign.

[0028] To this end, the present invention relates to a method for regulating the speed of a vehicle comprising validating a proposed change in set speed from a current set speed to a new set speed different from the current set speed and triggering a deceleration or acceleration of the vehicle from the current set speed to the new set speed if the proposed change in set speed is validated, characterized in that the method further comprises the following steps: checking a set of at least one condition relating to the dynamics of the vehicle and / or the environment of the vehicle; if the set of at least one condition is met at a given time instant, then production of the proposed change in set speed;determining the position of the vehicle in relation to a sign indicating a new speed limit, the new target speed being at most equal to the new speed limit;If the vehicle's position indicates that the vehicle is upstream of the indicator sign and if the time instant is within a defined time interval between two successive displays of proposed set speed changes, then a first signal is generated and emitted to a display means so that the proposed set speed change is displayed according to a first display mode; if the vehicle's position indicates that the vehicle is upstream of the indicator sign and if the time instant is outside the time interval, then a second signal is generated and emitted to the display means so that the proposed set speed change is displayed according to a second display mode, the first display mode being used to display a proposed set speed change once the vehicle has reached and passed the indicator sign.

[0029] According to one variant, the set of at least one condition includes at least one of the following conditions: a road on which the vehicle is traveling has an expected characteristic; a change of speed is not in progress; and / or the speed of the vehicle has not been changed for a specified period of time.

[0030] According to one variant, the new speed limit is obtained from the detection of a speed limit sign.

[0031] According to one variant, the new speed limit is obtained from map information.

[0032] According to one variant, the vehicle's position relative to the signpost is determined from the geographical positions of the vehicle and the signpost.

[0033] According to one variant, the vehicle's position relative to the signpost is determined from an on-board sensor in the vehicle.

[0034] According to a second aspect, the present invention relates to a vehicle speed regulation device, the device comprising a memory associated with a processor configured for the implementation of the steps of the process according to the first aspect of the present invention.

[0035] According to a third aspect, the present invention relates to a vehicle, for example of the automobile type, comprising a device as described above according to the second aspect of the present invention.

[0036] According to a fourth aspect, the present invention relates to a computer program which includes instructions adapted for carrying out the steps of the process according to the first aspect of the present invention, in particular when the computer program is executed by at least one processor.

[0037] Such a computer program can use any programming language, and be in the form of source code, object code, or an intermediate form between source code and object code, such as in a partially compiled form, or in any other desirable form.

[0038] According to a fifth aspect, the present invention relates to a computer-readable recording medium on which is recorded a computer program comprising instructions for carrying out the steps of the process according to the first aspect of the present invention.

[0039] On the one hand, the recording medium can be any entity or device capable of storing the program. For example, the medium can include a storage means, such as a ROM, a CD-ROM or a microelectronic circuit-type ROM, or a magnetic recording means or a hard drive.

[0040] On the other hand, this recording medium can also be a transmissible medium such as an electrical or optical signal, such a signal being able to be transmitted via an electrical or optical cable, by conventional or radio frequency, by self-directing laser beam, or by other means. The computer program according to the present invention can, in particular, be downloaded from a network such as the Internet.

[0041] Alternatively, the recording medium may be an integrated circuit in which the computer program is incorporated, the integrated circuit being adapted to execute or to be used in the execution of the process in question. Brief description of the figures

[0042] Other features and advantages of the present invention will become apparent from the description of the specific and non-limiting embodiments of the present invention below, with reference to figures 1 to 9 attached, on which: [ Fig. 1] illustrates a time diagram representing the operation of an AISA function according to the state of the art; [ Fig. 2 ] illustrates in a diagram examples of speed deceleration profiles as a function of the vehicle's distance from a sign indicating a new set speed, the vehicle speed, and the time at which a driver accepts a proposed change in set speed; Fig. 3 ] illustrates a flashing zone between two activation zones of the AISA and ISA functions according to the state of the art; [ Fig. 4 ] schematically illustrates a vehicle according to a particular and non-limiting embodiment of the present invention; [ Fig. 5 ] schematically illustrates a device configured to regulate the speed of a vehicle, according to a particular and non-limiting embodiment of the present invention; [ Fig. 6] illustrates a situation where a setpoint speed change proposal is generated by an AISA function according to a non-limiting embodiment of the present invention; [ Fig. 7 ] illustrates a situation where a setpoint speed change proposal is generated by an AISA function according to a non-limiting embodiment of the present invention; [ Fig. 8 ] illustrates a situation of producing a proposed change in setpoint speed by an ISA function according to a non-limiting embodiment of the present invention; and [ Fig. 9 ] illustrates a flowchart of the different stages of a vehicle speed regulation process, according to a particular and non-limiting embodiment of the present invention. Description of examples of achievements

[0043] A method and device for regulating the speed of a vehicle will now be described in what follows, with joint reference to figures 1 to 9 The same elements are identified with the same reference symbols throughout the description that follows.

[0044] There figure 4 schematically illustrates a vehicle V according to a particular and non-limiting embodiment of the present invention.

[0045] The present invention aims in particular to propose a method and a speed regulation device DR intended to allow speed regulation of the vehicle V in the presence of variable speed limits.

[0046] In what follows, vehicle V is considered, by way of non-limiting example, to be an automobile. For example, a car. However, the present invention is not limited to this type of vehicle. It relates to any type of land vehicle capable of traveling on roads subject to variable speed limits. Thus, it also relates, but is not limited to, commercial vehicles, motorcycles, buses, and trucks. Furthermore, in what follows, vehicle V is considered, by way of non-limiting example, to comprise a GM conventional powertrain (or PWM), that is to say, one whose only source of torque is an internal combustion engine.But this vehicle could include a hybrid type powertrain, i.e. comprising at least one internal combustion engine and at least one auxiliary machine capable of supplying torque from energy stored in energy storage means (such as an electric or compressed air motor), or an all-electric type, i.e. comprising at least one electric motor.

[0047] We have schematically represented on the figure 4 vehicle V comprising the GM powertrain (coupled at least to an accelerator pedal and a brake pedal), a CS supervisory computer for supervising the operation of the GM powertrain, and the DR speed control device according to the present invention.

[0048] For example, the V vehicle may include an onboard communication network, possibly multiplexed, allowing connected onboard electronic equipment (including the CS control unit and the onboard computer) to exchange information and instructions. Thus, the CS control unit can control the GM powertrain by transmitting instructions to it via the onboard communication network.

[0049] The speed regulation device DR is responsible for controlling the speed regulation of the vehicle V by means of set speeds selected by the driver CD or which he has determined, possibly according to instructions provided by the driver CD.

[0050] In the non-limiting example illustrated on the figure 4The DR speed control unit is part of the CS supervisory control unit. However, this is not mandatory. The DR speed control unit could, in fact, be a separate piece of equipment, possibly coupled to the CS supervisory control unit.

[0051] There figure 5 schematically illustrates an independent DR control device according to a particular and non-limiting embodiment of the present invention.

[0052] The DR device is, for example, configured to implement the operations described alongside the figures 6 , 7 and 8 and / or steps of the process described in relation to the figure 9Examples of such a DR device include, but are not limited to, embedded electronic equipment such as a vehicle's on-board computer, an electronic control unit such as an ECU (Electronic Control Unit), a smartphone, a tablet, and a laptop computer. The elements of the DR device, individually or in combination, can be integrated into a single integrated circuit, multiple integrated circuits, and / or discrete components. The DR device can be implemented as electronic circuits, software (or computer) modules, or a combination of electronic circuits and software modules.

[0053] The DR device includes one (or more) processor(s) 70 configured to execute instructions for carrying out the process steps and / or for executing instructions from the software embedded in the DR device. The processor 70 may include integrated memory, an input / output interface, and various circuits known to those skilled in the art. The DR device further includes at least one memory 71, for example, volatile and / or non-volatile memory, and / or includes a memory storage device that may include volatile and / or non-volatile memory, such as EEPROM, ROM, PROM, RAM, DRAM, SRAM, flash, magnetic disk, or optical disk.

[0054] The computer code of the embedded software(s) including the instructions to be loaded and executed by the processor is, for example, stored on memory 71.

[0055] According to various specific and non-limiting embodiment examples, the DR device is coupled in communication with other similar devices or systems and / or with communication devices, for example a TCU (Telematic Control Unit), for example via a communication bus or through dedicated input / output ports.

[0056] According to a specific, non-limiting embodiment, the DR device includes a block 72 of interface elements for communicating with external devices, such as a remote server or the cloud, or other nodes in the ad hoc network. The interface elements in block 72 include one or more of the following interfaces: radio frequency (RF) interface, for example of the Wi-Fi® type (according to IEEE 802.11), for example in the 2.4 or 5 GHz frequency bands, or of the Bluetooth® type (according to IEEE 802.15.1), in the 2.4 GHz frequency band, or of the Sigfox type using UBN (Ultra Narrow Band) radio technology, or LoRa in the 868 MHz frequency band, LTE (Long-Term Evolution), LTE-Advanced; USB (Universal Serial Bus) interface; HDMI (High Definition Multimedia Interface); LIN (Local Interconnect Network) interface.

[0057] Data is for example loaded to the DR device via the interface of block 72 using a Wi-Fi ®< network such as according to IEEE 802.11, an ITS G5 network based on IEEE 802.11p or a mobile network such as a 4G (or 5G) network based on the LTE (Long Term Evolution) standard defined by the 3GPP consortium, in particular an LTE-V2X network.

[0058] According to another particular and non-limiting embodiment, the DR device includes a communication interface 73 which enables communication with other devices (such as other computers in the embedded system and in particular the CS supervisory computer) via a communication channel 74. The communication interface 73 corresponds, for example, to a transmitter configured to transmit and receive information and / or data via the communication channel 74. The communication interface 73 corresponds, for example, to a wired network of the CAN (Controller Area Network) type, CAN FD (Controller Area Network Flexible Data-Rate) type, FlexRay (standardized by ISO 17458) or Ethernet (standardized by ISO / IEC 802-3).

[0059] According to a particular and non-limiting embodiment, the DR device can provide output signals to one or more external devices, such as a display screen 75, touch or non-touch, one or more speakers 76 and / or other peripherals 77 such as a head-up display device via output interfaces 78, 79 and 80 respectively.

[0060] According to one variant, one or the other of the external devices is integrated into the DR device.

[0061] The DR cruise control system is activated by the driver CD of vehicle V using a control device, possibly a dedicated one, or a dedicated voice command, or by selecting an option from a menu displayed on a screen in vehicle V (for example, the central instrument cluster installed in the vehicle's dashboard). The control device may, for example, be a lever (or a stalk), possibly a dedicated one.

[0062] When the DR control device is activated, in a first operation, the DR control device obtains a new speed limit.

[0063] According to one variant, a new speed limit can be obtained from the detection of a speed limit sign. This detection can, for example, be implemented by a sensor located at the front of vehicle V. This sensor can also provide a position PV of the vehicle relative to vehicle V.

[0064] According to one variant, a new speed limit can be obtained from map information that indicates the geographical position of a sign indicating this new speed limit.

[0065] According to one variant, this map information can be obtained from memory 71 of the DR control device or from a map database stored in memory 71. The map information is defined according to the geographical position of the vehicle V.

[0066] According to one variant, this cartographic information can also be obtained from a communication network.

[0067] In a second operation, the DR control device checks whether a set E of at least one condition relating to the vehicle dynamics and / or the vehicle environment is verified.

[0068] In one variant, a condition relating to the vehicle's environment relates to the road on which the vehicle is traveling. This condition is verified, for example, by whether the road is eligible or whether the road is a special type of road such as a motorway.

[0069] According to one variant, a condition relating to vehicle dynamics is related to a change in vehicle speed.

[0070] For example, this condition is verified if a change of speed is not in progress or if the speed of the vehicle V has not been modified for a specified period of time.

[0071] In a third operation, if the set E of conditions is verified at a time instant T, then the regulation device DR produces a proposal for a change in the setpoint speed going from a current setpoint speed of the vehicle V to a new setpoint speed different from the current setpoint speed.

[0072] The new target speed is at most equal to the new limiting speed obtained. Typically, the new target speed is equal to the new limiting speed.

[0073] In a fourth operation, the DR control device determines the PV position of the vehicle V relative to a position of a sign indicating the new speed limit.

[0074] In one variant, the vehicle's position is determined by a GPS (Global Positioning System) and the sign's position is determined by map data. The vehicle's position PV relative to the sign is then obtained from the geographical positions of the vehicle V and the sign.

[0075] According to one variant, an on-board sensor of vehicle V gives the position PV of vehicle V relative to the position of the sign indicating the new speed limit.

[0076] In a fifth operation, if the position PV of vehicle V indicates that vehicle V is upstream of the indicator sign and if the time instant T is within a time interval TF defined between two successive displays of proposed set speed changes, then a first signal is generated and emitted (95) to a display means 75 or 80 so that the proposed set speed change is displayed according to the first display mode M1; if the position of the vehicle indicates that the vehicle is upstream of the indicator sign and if the time instant T is outside the time interval TF, then a second signal is generated and emitted (95) to the display means 75 or 80 so that the proposed set speed change is displayed according to the second display mode M2.

[0077] As a reminder, the first display mode M1 is used to display a proposed change of set speed once the vehicle has reached and passed the indicator sign (ISA function).

[0078] In a sixth operation, the displayed proposal is validated automatically or by the CD driver.

[0079] According to one variant, this validation can be carried out by means of a control device, possibly dedicated, or a dedicated voice command, or even by selecting an option from a menu displayed on a screen of the vehicle V.

[0080] In a seventh operation, the DR control device triggers a deceleration or acceleration of the vehicle V so that its speed changes from the current set speed to the new set speed.

[0081] THE figures 6 , 7 and 8illustrate situations of production of a proposal for change of setpoint speed by an AISA or ISA function according to a non-limiting example of an embodiment of the present invention.

[0082] According to these examples, the speed of vehicle V is regulated according to a current setpoint speed of 130 km / h. The control device DR obtains a new speed limit of 110 km / h, and the AISA function is activated, thus generating a change in the setpoint speed. Let's assume that at a time T, the set E of conditions is met. The control device DR then generates a proposed change in the setpoint speed from the current setpoint speed of 130 km / h to a new setpoint speed equal to the new speed limit of 110 km / h. The control device DR then determines the position PV of vehicle V relative to the position of a sign indicating the new speed limit.

[0083] Following the example of the figure 6 The time instant T is outside the time interval TF, and the position PV indicates that the vehicle V is upstream of the signpost. The DR control device then generates a second signal, which it transmits to a display 75 or 80, so that the proposed change in set speed is displayed according to the second display mode M2.

[0084] Following the example of the figure 7 The time instant T is within the time interval TF, and the position PV indicates that the vehicle V is upstream of the signpost. The control device DR then generates a first signal, which it transmits to a display 75 or 80, so that the proposed change in set speed is displayed according to the first display mode M1.

[0085] Following the example of the figure 8The PV position indicates that vehicle V is downstream of the indicator sign. The DR control device then generates an initial signal which it transmits to a display unit 75 or 80 so that the proposed change in target speed is displayed according to the first display mode M1.

[0086] There figure 9 illustrates a flowchart of the different stages of a vehicle speed regulation process, according to a particular and non-limiting embodiment of the present invention. The process is implemented, for example, by a device embedded in vehicle V or by device DR of the figure 5 .

[0087] In the first stage 91, a new speed limit is obtained.

[0088] In a second step 92, a set E of at least one condition relating to the vehicle dynamics and / or the vehicle environment is checked.

[0089] In a third step 93, if the set E of conditions is met at a time T, then a proposal for a change in the setpoint speed, moving from the vehicle's current setpoint speed to a new setpoint speed different from the current setpoint speed, is generated; the device has thus created the proposal for a change in the setpoint speed.

[0090] In a fourth step 94, the position of the vehicle relative to a position of a sign indicating the new speed limit is determined.

[0091] In a fifth step 95, if the vehicle position indicates that the vehicle is upstream of the indicator sign and if the time instant T is within a time interval TF defined between two successive displays of set speed change proposals, then a first signal is generated and emitted to a display means so that the set speed change proposal is displayed according to a first display mode; if the vehicle position indicates that the vehicle is upstream of the indicator sign and if the time instant T is outside the time interval TF, then a second signal is generated and emitted to the display means so that the set speed change proposal is displayed according to a second display mode, the first display mode being used to display a set speed change proposal once the vehicle has reached and passed the indicator sign.

[0092] In a sixth step 96, the proposed change of setpoint speed displayed is validated automatically or by a driver of the vehicle.

[0093] In a seventh step 97, an acceleration or deceleration of the vehicle is triggered from the current set speed to the new set speed.

[0094] According to one variant, the variants and examples of the operations described in relation to the figures 4 to 8 apply to the steps of the process of the figure 9 .

[0095] The speed control process of a vehicle may include secondary steps. The same applies to the device configured to implement the process.

[0096] The present invention also relates to a vehicle, for example a motor vehicle or more generally an autonomous land-based motor vehicle, comprising the DR device of the figure 5 .

Claims

1. A method for regulating the speed of a vehicle comprising validating (96) a proposed change in set speed from a current set speed to a new set speed different from the current set speed and triggering (97) a deceleration or acceleration of the vehicle from the current set speed to the new set speed if the proposed change in set speed is validated, characterized in that the method further comprises the following steps: checking (92) a set of at least one condition relating to the dynamics of the vehicle and / or the environment of the vehicle; producing (93) the proposed change in set speed if the set of at least one condition is met at a time instant; determining (94) a position of the vehicle relative to a sign indicating a new speed limit, the new set speed being at most equal to the new speed limit; If the vehicle's position indicates that the vehicle is upstream of the indicator sign and if the time instant is within a defined time interval between two successive displays of proposed set speed changes, then a first signal is generated and emitted (95) to a display means so that the proposed set speed change is displayed according to a first display mode ; if the vehicle's position indicates that the vehicle is upstream of the indicator sign and if the time instant is outside the time interval, then a second signal is generated and emitted (95) to the display means so that the proposed set speed change is displayed according to a second display mode, the first display mode being used to display a proposed set speed change once the vehicle has reached and passed the indicator sign.

2. A method according to claim 1, wherein the set of at least one condition includes at least one of the following conditions: - a road on which the vehicle is traveling has an expected characteristic; - a change of speed is not in progress; and / or - the speed of the vehicle has not been changed for a specified period.

3. A method according to claim 1 or 2, wherein the new speed limit is obtained from a detection of a speed limit sign.

4. A method according to claim 1 or 2, wherein the new speed limit is obtained from map information.

5. A method according to any one of claims 1 to 4, wherein the position of the vehicle relative to the signpost is determined from geographical positions of the vehicle and the signpost.

6. A method according to any one of claims 1 to 4, wherein the position of the vehicle relative to the indicator sign is determined from a sensor on board the vehicle.

7. Computer program comprising instructions implementing the method according to any one of the preceding claims, when such instructions are executed by a processor.

8. Computer-readable recording medium on which a computer program according to claim 7 is recorded.

9. Vehicle speed control device (DR), said device (DR) comprising a memory (71) associated with at least one processor (70) configured for the implementation of the steps of the method according to any one of claims 1 to 6.

10. Vehicle (V) comprising the device (DR) according to claim 9.