Adaptive cruise control method and system

Abstract

The present application relates to a kind of adaptive cruise control methods, comprising: the speed of at least two front vehicles in the same lane with vehicle and the speed of vehicle are collected acquisition step;Two front vehicles speed keeps stable state time is calculated, and whether two front vehicles speed keeps stable state time is greater than or equal to the judgment step of first set time, wherein, speed keeps stable state refers to speed is substantially maintained at a certain speed, speed deviation value is less than first threshold value;And in the case where two front vehicles speed keeps stable state time is greater than or equal to first set time, the distance of adaptive cruise system preset to vehicle is corrected at certain time interval, and it is corrected as correction distance, so that the distance between vehicle and adjacent front vehicle can be controlled as correction distance correction step.The present application also relates to a kind of adaptive cruise control system.

Description

Technical Field

[0001] This invention relates to the field of vehicle safety control technology, and in particular to an adaptive cruise control method and an adaptive cruise control system. Background Technology

[0002] The Adaptive Cruise Control (ACC) system senses the driving environment ahead through a perception system (currently mostly using vehicle-mounted millimeter-wave radar). The controller calculates and provides appropriate control values ​​to control the throttle and braking system of the power unit, automatically adjusting the vehicle speed and distance to automate longitudinal driving operations.

[0003] Due to limitations in the design capabilities of current perception systems, erroneous triggering of advanced driver assistance (ADA) functions (e.g., erroneous triggering of Electronic Brake Assist (EBA)) is difficult to avoid during the activation of ADADA features. However, current system designs only consider single-point failure (single-vehicle failure), neglecting multi-point failure scenarios (multiple vehicles with ACC activated traveling together). With the increasing prevalence and development of ADADA features in recent years, more and more vehicles on the road are equipped with these features. In situations where multiple vehicles have ACC activated, an emergency braking incident caused by erroneous triggering in one vehicle could affect following vehicles, creating a chain reaction and increasing the risk of traffic accidents. Summary of the Invention

[0004] This invention was made to solve the above-mentioned problems, and its purpose is to provide an adaptive cruise control method and an adaptive cruise control system that fully consider the possible impact of the failure of the preceding vehicle with ACC function also activated, thereby reducing the overall risk of the road.

[0005] According to one aspect of the present invention, an adaptive cruise control method is provided, comprising: a data acquisition step, acquiring the vehicle speeds of at least two vehicles in the same lane as the vehicle and the vehicle speed; a judgment step, calculating the time during which the speeds of the at least two vehicles in the lane remain stable, and judging whether the time during which the speeds of the at least two vehicles in the lane remain stable is greater than or equal to a first preset time, wherein maintaining a stable speed means that the vehicle speed is basically maintained at a certain speed and the speed deviation value is less than a first threshold; and a correction step, wherein if the time during which the speeds of the at least two vehicles in the lane remain stable is greater than or equal to the first preset time, the distance preset by the adaptive cruise control system of the vehicle is corrected at certain time intervals to a corrected distance, thereby enabling the distance between the vehicle and adjacent vehicles in the lane to be controlled as a corrected distance.

[0006] Preferably, in the correction step, the corrected vehicle distance is set according to a three-dimensional parameter table or three-dimensional feature curve pre-stored in the vehicle. The three-dimensional parameter table consists of three parameters: the time it takes for the speed of the adjacent preceding vehicle to remain stable, the vehicle speed, and the corrected vehicle distance. The three axes of the three-dimensional feature curve represent the time it takes for the speed of the adjacent preceding vehicle to remain stable, the vehicle speed, and the corrected vehicle distance, respectively.

[0007] Preferably, in the correction step, the corresponding corrected vehicle distance is selected from the three-dimensional parameter table or the three-dimensional feature curve at certain time intervals based on the time it takes for the speed of the adjacent preceding vehicle to remain stable and the speed of the vehicle.

[0008] Preferably, in the data acquisition step, the speeds of the at least two preceding vehicles and the speed of the vehicle are acquired using a sensor device installed on the vehicle.

[0009] Preferably, in the data acquisition step, the vehicle speeds of the at least two preceding vehicles and the vehicle itself are acquired through a vehicle-to-X communication system.

[0010] Preferably, the vehicle speed is greater than or equal to 80 kph.

[0011] Preferably, the first set time is set to 60 seconds.

[0012] Preferably, the first threshold is set to 5 kph.

[0013] Preferably, the time interval is set to 20 seconds.

[0014] According to another aspect of the present invention, an adaptive cruise control system is provided, comprising: a data acquisition module for acquiring the vehicle speeds of at least two vehicles ahead of the vehicle in the same lane as the vehicle, and the vehicle speed of the vehicle; a judgment module for calculating the time during which the speeds of the at least two vehicles ahead remain stable, and judging whether the time during which the speeds of the at least two vehicles ahead remain stable is greater than or equal to a first preset time, wherein maintaining a stable speed means that the vehicle speed is basically maintained at a certain speed and the speed deviation value is less than a first threshold; and a correction module for correcting the vehicle distance preset by the adaptive cruise system of the vehicle at certain time intervals when the time during which the speeds of the at least two vehicles ahead remain stable reaches the first preset time, thereby correcting the distance between the vehicle and the adjacent vehicles ahead to a corrected distance.

[0015] Preferably, in the correction module, the corrected vehicle distance is set according to a three-dimensional parameter table pre-stored in the vehicle. The three-dimensional parameter table consists of three parameters: the time during which the speeds of adjacent vehicles in at least two preceding vehicles remain stable, the vehicle speed, and the corrected vehicle distance.

[0016] Preferably, in the correction module, the corresponding corrected vehicle distance is selected from the three-dimensional parameter table at certain time intervals based on the time it takes for the speed of the adjacent preceding vehicle to remain stable and the speed of the vehicle.

[0017] According to the present invention, by optimizing the spacing between vehicles, the overall road risk can be reduced. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the working conditions involved in the embodiments of the present invention.

[0019] Figure 2 This is a flowchart of the adaptive cruise control method involved in the embodiments of the present invention.

[0020] Figure 3 This is an example of a three-dimensional parameter diagram used in the adaptive cruise control method involved in the embodiments of the present invention.

[0021] Figure 4 This is a structural block diagram of the adaptive cruise control system involved in the embodiments of the present invention. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0023] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. As used herein, the singular forms “a” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising” and / or “made of” are used in this specification, the presence of the said feature, integral, step, operation, element, and / or component is specified, but the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof is not excluded.

[0024] Unless otherwise specified, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and this disclosure, and will not be interpreted as having an idealized or overly formal meaning, unless expressly so defined herein.

[0025] Figure 1 This is a schematic diagram of the working conditions involved in the embodiments of the present invention. Figure 2This is a flowchart of the adaptive cruise control method involved in the embodiments of the present invention. Utilizing Figure 1 and Figure 2 The adaptive cruise control method according to an embodiment of the present invention will be described.

[0026] The working condition involved in this embodiment of the invention is: on a road of a certain length, multiple vehicles have activated their ACC function. In this situation, due to the short distance between vehicles and the fact that all vehicles have activated their ACC function, an emergency braking caused by the accidental activation of functions such as EBA by the vehicle in front may affect the vehicles behind.

[0027] like Figure 2 As shown, the adaptive cruise control method involved in this embodiment of the invention includes the following steps:

[0028] In step S101, the speeds of the two vehicles in front of vehicle 1 in the same lane as vehicle 1 and the speed of vehicle 1 are collected.

[0029] by Figure 1 Taking the diagram shown as an example, this vehicle is vehicle 1, vehicle C1 is the closest preceding vehicle to vehicle 1 in the same lane, and vehicle C2 is the closest preceding vehicle to vehicle C1 in the same lane. Here, vehicle C1 and vehicle C2 are collectively referred to as the preceding vehicles of vehicle 1, while vehicle C1 is referred to as the adjacent preceding vehicle of vehicle 1.

[0030] In this embodiment, the speeds of vehicles C1 and C2 are collected using a millimeter-wave radar installed on vehicle 1, and the speed of vehicle 1 itself is collected using a speed sensor installed on vehicle 1.

[0031] However, the present invention is not limited to using vehicle-mounted sensor devices (millimeter-wave radar, vehicle speed sensor) to collect the above information, but can also use sensor devices installed in infrastructure for detection and transmit the above information through a vehicle-to-X communication system.

[0032] In addition, in this embodiment, only the speeds of the two vehicles in front of vehicle 1 in the same lane are collected. However, the present invention is not limited to this and the speeds of more than two vehicles in front of vehicle 1 in the same lane can also be collected.

[0033] In step S102, based on the real-time vehicle speeds of vehicles C1 and C2 collected in step S101, the time during which the speeds of vehicles C1 and C2 remain stable can be calculated, and it can be determined whether the time during which the speeds of the two vehicles C1 and C2 remain stable is greater than or equal to a first preset time T1. Here, maintaining a stable speed means that the speed is basically maintained at a certain value, and the speed deviation is less than a small first threshold Th1. In this invention, the first threshold Th1 is 5 kph; of course, the first threshold can also be other smaller values. That is to say, the speeds of vehicles C1 and C2 are basically maintained at a certain speed, and their respective speed deviations are less than the first threshold Th1. Here, vehicles C1 and C2 do not need to maintain the same speed; the speed of vehicle C1 can be maintained at V1, and the speed of vehicle C2 can be maintained at V2.

[0034] In this embodiment, the first set time T1 is set to 60 seconds. Of course, this first set time T1 can be set to other values ​​according to design needs. Furthermore, since the risk of collateral damage due to the failure of the vehicle in front is significant during high-speed adaptive cruise control, it can have a substantial impact on road safety. Therefore, it is preferable to limit a certain vehicle speed to a value greater than or equal to 80 kph.

[0035] If the determination in step S102 is yes, proceed to step S103; if the determination in step S102 is no, end the process.

[0036] In step S103, when the speeds of the two preceding vehicles C1 and C2 remain stable for a period greater than or equal to a first preset time T1, a corresponding corrected distance is selected from the three-dimensional parameter table at regular intervals based on the time the speed of the adjacent preceding vehicle C1 remains stable and the speed of vehicle 1. This regular interval can be set as needed; in this embodiment, it is set to 20 seconds. That is, when the speeds of the two preceding vehicles C1 and C2 remain stable for a period greater than or equal to the first preset time, a corrected distance is selected at 20-second intervals, and the preset distance of vehicle 1's adaptive cruise control system is corrected to the newly selected corrected distance. Of course, if the corrected distance is equal to the preset distance of vehicle 1's adaptive cruise control system, no correction is required.

[0037] Figure 3 This is an example of a three-dimensional parameter map used in the adaptive cruise control method of this invention. The three-dimensional parameter table can be pre-stored in vehicle 1. The three-dimensional parameter table consists of three parameters: the time it takes for the speed of the adjacent preceding vehicle to remain stable, the vehicle speed, and the corrected distance.

[0038] like Figure 3As shown, the values ​​recorded in the first column represent the time that the adjacent vehicle C1 remains stable, the values ​​recorded in the first row represent the vehicle speed, and the remaining values ​​in the table represent the corrected distance. For example, when vehicle 1's speed is 80 kph and the adjacent vehicle C1 remains stable for 60 seconds, the corrected distance is 45 meters; when vehicle 1's speed is 90 kph and the adjacent vehicle C1 remains stable for 80 seconds, the corrected distance is 51 meters.

[0039] In step S104, the preset distance of the adaptive cruise system of vehicle 1 is corrected to the corrected distance obtained in step S103, so that the distance between vehicle 1 and the adjacent preceding vehicle C1 can be controlled to the corrected distance, and then the process ends.

[0040] Furthermore, while the above embodiments select the corresponding corrected distance based on a three-dimensional parameter table, the present invention is not limited to this. It is also possible to pre-store a three-dimensional feature curve containing the relationship between the time it takes for adjacent vehicles to maintain a stable speed, the vehicle speed, and the corrected distance. That is, the three axes of this three-dimensional feature curve represent the time it takes for adjacent vehicles to maintain a stable speed, the vehicle speed, and the corrected distance, respectively. The corresponding corrected distance can be selected from the three-dimensional feature curve based on the time it takes for adjacent vehicles to maintain a stable speed and the vehicle speed.

[0041] Figure 4 This is a structural block diagram of the adaptive cruise control system involved in the embodiments of the present invention.

[0042] The adaptive cruise control system 100 in this embodiment includes: a data acquisition module 110, a judgment module 120, and a correction module 130.

[0043] The acquisition module 110 acquires the speeds of two vehicles C1 and C2 in the same lane as vehicle 1, as well as the speed of vehicle 1 itself. In this embodiment, the speeds of vehicles C1 and C2 are acquired using a millimeter-wave radar installed on vehicle 1, and the speed of vehicle 1 itself is acquired using a speed sensor installed on vehicle 1.

[0044] However, the present invention is not limited to using vehicle-mounted sensor devices (millimeter-wave radar, vehicle speed sensor) to collect the above information, but can also use sensor devices installed in infrastructure for detection and transmit the above information through a vehicle-to-X communication system.

[0045] In addition, in this embodiment, only the speeds of the two vehicles in front of vehicle 1 in the same lane are collected. However, the present invention is not limited to this and the speeds of more than two vehicles in front of vehicle 1 in the same lane can also be collected.

[0046] The judgment module 110 first calculates the time during which the speeds of the two preceding vehicles C1 and C2 remain stable based on the speeds collected by the acquisition module 110. Then, it determines whether the time during which the speeds of the two preceding vehicles C1 and C2 remain stable is greater than or equal to a first preset time T1. Maintaining a stable speed means that the speed is basically maintained at a certain level, and the speed deviation is less than a first threshold Th1. In this invention, the first threshold Th1 is 5 kph; however, other smaller values ​​can also be used.

[0047] In this embodiment, the first set time T1 is set to 60 seconds. Furthermore, since the risk of collateral damage due to the failure of the vehicle in front is significant during high-speed adaptive cruise control, it can have a substantial impact on road safety. Therefore, it is preferable to limit a certain vehicle speed to a value greater than or equal to 80 kph.

[0048] If the speeds of the two preceding vehicles C1 and C2 remain stable for a set time T1, the correction module 130 corrects the preset distance of the adaptive cruise control system of vehicle 1 at regular intervals, adjusting it to a corrected distance. This maintains the distance between vehicle 1 and the adjacent preceding vehicle C1 at the corrected distance, thereby reducing the risk of collateral damage caused by the failure of the preceding vehicle and lowering the overall road risk. The specific time interval can be set according to design requirements; in this embodiment, it is set to 20 seconds.

[0049] Furthermore, the corrected distance here is selected from a three-dimensional parameter table pre-stored in vehicle 1 based on the time it takes for the speed of the adjacent preceding vehicle C1 to remain stable and the speed of vehicle 1 at certain time intervals. This three-dimensional parameter table consists of three parameters: the time it takes for the speed of the adjacent preceding vehicle among at least two preceding vehicles to remain stable, the vehicle speed, and the corrected distance.

[0050] This invention reduces overall road risk by optimizing the distance between vehicles, and is especially suitable for future driving conditions where advanced driver assistance systems will be used more frequently.

[0051] Those skilled in the art will recognize that the modules, units, and method steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of electronic hardware and software, the components and steps of the examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in electronic hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can implement the described functions using different methods for each specific application, but such implementations should not be considered beyond the scope of the invention.

[0052] Although the present invention has been described with reference to specific embodiments, those skilled in the art should recognize that the scope of the invention is not limited to the specific combinations of the above-described technical features, but also includes other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in the present invention.

Claims

1. A method of adaptive cruise control, characterized by, comprising: a collecting step of collecting vehicle speeds of at least two preceding vehicles located in the same lane as the vehicle and a vehicle speed of the vehicle; a judging step of calculating a time during which the vehicle speeds of the at least two preceding vehicles are in a stable state and judging whether the time during which the vehicle speeds of the at least two preceding vehicles are in the stable state is greater than or equal to a first set time, wherein the stable state means that the vehicle speeds are substantially maintained at a certain vehicle speed and a vehicle speed deviation value is less than a first threshold value; and a correcting step of correcting a vehicle distance preset by an adaptive cruise control system of the vehicle to a corrected vehicle distance at a certain time interval in a case where the time during which the vehicle speeds of the at least two preceding vehicles are in the stable state is greater than or equal to the first set time, thereby controlling a vehicle distance between the vehicle and the adjacent preceding vehicle to the corrected vehicle distance, in the correcting step, the corrected vehicle distance is set according to a three-dimensional parameter table or a three-dimensional characteristic curve stored in the vehicle in advance, the three-dimensional parameter table is composed of three parameters, which are the time during which the vehicle speeds of the adjacent preceding vehicles are in the stable state, the vehicle speed of the vehicle, and the corrected vehicle distance, three axes of the three-dimensional characteristic curve respectively represent the time during which the vehicle speeds of the adjacent preceding vehicles are in the stable state, the vehicle speed of the vehicle, and the corrected vehicle distance, in the three-dimensional parameter table and the three-dimensional characteristic curve, the corrected vehicle distance is increased not only with an increase in the vehicle speed of the vehicle but also with an increase in the time during which the vehicle speeds of the adjacent preceding vehicles are in the stable state.

2. The adaptive cruise control method according to claim 1, wherein in the collecting step, the vehicle speeds of the at least two preceding vehicles and the vehicle speed of the vehicle are collected by using a sensor device installed in the vehicle.

3. The adaptive cruise control method according to claim 1, wherein in the collecting step, the vehicle speeds of the at least two preceding vehicles and the vehicle speed of the vehicle are collected by a car-to-X communication system.

4. The adaptive cruise control method according to any one of claims 1 to 3, wherein the certain vehicle speed is a vehicle speed of 80 kph or more.

5. The adaptive cruise control method according to any one of claims 1 to 3, wherein the first set time is set to 60 seconds.

6. The adaptive cruise control method according to any one of claims 1 to 3, wherein the first threshold value is set to 5 kph.

7. The adaptive cruise control method according to any one of claims 1 to 3, wherein the certain time interval is set to 20 seconds.

8. An adaptive cruise control system characterized by, comprising: a collecting module of collecting vehicle speeds of at least two preceding vehicles located in the same lane as the vehicle and a vehicle speed of the vehicle; a judging module of calculating a time during which the vehicle speeds of the at least two preceding vehicles are in a stable state and judging whether the time during which the vehicle speeds of the at least two preceding vehicles are in the stable state is greater than or equal to a first set time, wherein the stable state means that the vehicle speeds are substantially maintained at a certain vehicle speed and a vehicle speed deviation value is less than a first threshold value; and a correcting module of correcting a vehicle distance preset by an adaptive cruise control system of the vehicle to a corrected vehicle distance at a certain time interval in a case where the time during which the vehicle speeds of the at least two preceding vehicles are in the stable state is greater than or equal to the first set time, thereby controlling a vehicle distance between the vehicle and the adjacent preceding vehicle to the corrected vehicle distance, The correction module corrects the vehicle distance preset by the adaptive cruise control system of the vehicle to a corrected vehicle distance at a certain time interval when the time that the speed of the adjacent preceding vehicle remains stable reaches a first set time, so as to control the distance between the vehicle and the adjacent preceding vehicle to be the corrected vehicle distance. In the correction module, the corrected vehicle distance is set according to a three-dimensional parameter table or a three-dimensional characteristic curve pre-stored in the vehicle, the three-dimensional parameter table is composed of three parameters, namely the time that the speed of the adjacent preceding vehicle remains stable, the speed of the vehicle and the corrected vehicle distance, and the three axes of the three-dimensional characteristic curve represent the time that the speed of the adjacent preceding vehicle remains stable, the speed of the vehicle and the corrected vehicle distance respectively. In the three-dimensional parameter table and the three-dimensional characteristic curve, the corrected vehicle distance increases not only with the increase of the speed of the vehicle, but also with the increase of the time that the speed of the adjacent preceding vehicle remains stable.

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