Adaptive cruise control method

Abstract

The present disclosure relates to an adaptive cruise control method, comprising: a selection step of selecting a target vehicle in an adjacent lane in front of a host vehicle that may cut into the host vehicle; a first calculation step: calculating the average yaw rate of the selected target vehicle towards the lane; a second calculation step: calculating the vehicle body proportion of the target vehicle entering the lane through the calculated average yaw rate; a comparison step: comparing the vehicle body proportion with a preset proportion threshold value; and a determination step: if the vehicle body proportion is greater than the proportion threshold value, determining that the target vehicle is cut into the lane to run in front of the vehicle, and taking an action for coping with the cut-in behavior of the target vehicle in the vehicle. The disclosure also relates to a domain controller and a computer program product.

Description

Technical Field

[0001] The present application relates to an adaptive cruise control method. The present invention also relates to a domain controller and a computer program product for implementing the adaptive cruise control method. Background Art

[0002] With the development of science and technology, the driver assistance / autonomous driving functions of vehicles are becoming more and more powerful, and more and more vehicles are equipped with advanced driver assistance systems. Adaptive Cruise Control (ACC) is one of the basic functions of ADAS. Its main purpose is to automatically select the appropriate moving vehicle in front of the vehicle as the target vehicle, and automatically control the longitudinal motion state of the vehicle in real time according to the speed of the target vehicle and the distance between the vehicle and the target vehicle.

[0003] One challenge facing current ADAS systems is that ADAS needs to correctly process all targets detected by sensors, which may include multiple targets in the three lanes in front of the vehicle (the lane where the vehicle is located, the lane to the left of the vehicle, and the lane to the right of the vehicle).

[0004] In addition, the ADAS system takes too long to judge the cutting-in behavior of the vehicle in the adjacent lane ahead of the vehicle, especially when a truck with a large yaw angle cuts in. Therefore, the current ADAS system cannot quickly select the target vehicle when the vehicle in the adjacent lane ahead cuts in, making it difficult for ACC to control the longitudinal speed in time, thereby reducing the product performance of the ADAS.

[0005] Therefore, a method is needed that can accurately and in real time identify lane change behavior from a lane other than the vehicle's lane to the lane in front of the vehicle's lane to ensure that the vehicle's ACC function can safely and comfortably control the vehicle to maintain a safe distance from the target vehicle ahead. Summary of the invention

[0006] In view of the above problems, the present invention aims to provide an adaptive cruise control method, and more specifically, to provide a method that can real-time and correctly identify the lane change behavior of cutting into the lane in front of the vehicle from a lane other than the vehicle's lane to ensure that the ACC function of the vehicle can safely and comfortably control the vehicle to maintain a safe distance from the target vehicle ahead.

[0007] According to one aspect of the present invention, an adaptive cruise control method is provided, comprising: a selection step of selecting a target vehicle in the adjacent lane in front of the host vehicle that may cut into the host lane; a first calculation step of calculating the average yaw rate of the selected target vehicle toward the host lane; a second calculation step of calculating the body proportion of the target vehicle entering the host lane by means of the average yaw rate obtained by calculation; a comparison step of comparing the body proportion with a preset proportion threshold; a determination step of determining that the target vehicle will cut into the host lane and travel in front of the host vehicle if the body proportion is greater than the proportion threshold, and taking actions in the host vehicle to respond to the cutting-in behavior of the target vehicle.

[0008] According to another aspect of the present invention, a domain controller is provided, comprising: at least one processor, and a memory coupled to the at least one processor, the memory storing a computer program, and when the computer program is executed by the at least one processor, the method according to the first aspect of the present invention is implemented.

[0009] The present invention also provides a computer program product, comprising a computer program, which, when executed by a computer, causes the computer to execute the method according to the first aspect of the present invention.

[0010] According to the adaptive cruise control method of the present invention, the lane change behavior of cutting into the lane in front of the vehicle from a lane other than the vehicle's lane can be identified in real time and correctly, reducing the misjudgment of the lane change behavior of the target vehicle in front of the vehicle, preventing ACC's misbraking or misacceleration, thereby providing a safe and comfortable travel experience for the vehicle driver or passengers. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings, in which:

[0012] Figure 1 The schematic diagram exemplarily shows a situation in which a vehicle in an adjacent lane is about to cut into the lane where the host vehicle is located according to an embodiment of the present invention.

[0013] Figure 2 A schematic diagram exemplarily shows a situation in which a vehicle in an adjacent lane is about to cut into the lane where the host vehicle is located according to another embodiment of the present invention.

[0014] Figure 3 The relationship of the coefficients in formula (4) according to one embodiment with respect to the longitudinal distance between the target vehicle and the host vehicle is exemplarily shown.

[0015] Figure 4A flow chart of a method for determining whether a vehicle in an adjacent lane cuts into a lane where the host vehicle is located according to an embodiment of the present invention is exemplarily shown.

[0016] According to the detailed description carried out below in conjunction with the accompanying drawings, other purposes and features of the embodiments of this invention will become apparent. However, it should be understood that the accompanying drawings are designed only for illustrative purposes and are not intended to limit the scope of the present invention. DETAILED DESCRIPTION

[0017] The vehicle in the present invention has a driver assistance system, in particular an advanced driver assistance system (ADAS). The vehicle has at least a yaw rate sensor, a steering torque sensor and a vehicle speed sensor, and they can be at any suitable position in the vehicle, although not mentioned in this article, if necessary, other sensors besides the above sensors are also possible.

[0018] Figure 1 The schematic diagram exemplarily shows a situation in which a vehicle in an adjacent lane is about to cut into the lane where the host vehicle is located according to an embodiment of the present invention.

[0019] Figure 1 There are three lanes on the road shown in FIG. 1 . The host vehicle 10 is traveling in the host lane L2 located in the middle. In the adjacent lane L3 to the right of the host vehicle 10, there is a target vehicle 30. The lane to the left of the host vehicle 10 is lane L1. The lane boundary between lane L1 and host lane L2 is B2, and the lane boundary between host lane L2 and adjacent lane L3 is B1. Figure 1 In the example, the host vehicle 10 is driving in the host lane L2 following the front vehicle 20 in an adaptive cruise mode. The target vehicle 30 is driving in the adjacent lane L3 of the host lane L2 and intends to cut in front of the host vehicle 10 in the host lane L2, that is, cut in between the host vehicle 10 and the front vehicle 20.

[0020] Figure 2 A schematic diagram exemplarily shows a situation in which a vehicle in an adjacent lane is about to cut into the lane where the host vehicle is located according to another embodiment of the present invention.

[0021] exist Figure 2 In the example, the host vehicle 10 is traveling in the host lane L2 in an adaptive cruise mode and is not following any vehicle ahead. The target vehicle 30 is traveling in the adjacent lane L3 of the host lane L2 and intends to cut in front of the host vehicle 10 in the host lane L2. Figure 2 The dotted line frame in the figure represents the target vehicle position detected by the prior art, and the solid line frame represents the target vehicle position corrected by the method of the present invention and closer to the actual situation.

[0022] Combine the following Figure 2The principle of the method for judging that the target vehicle 30 in the adjacent lane L3 cuts into the lane L2 where the host vehicle 10 is located is described in detail. The lane boundary between the adjacent lane L3 and the host lane L2 is B1. The host vehicle 10 and the target vehicle 30 are traveling in the longitudinal direction of the road. Figure 2 The x direction is shown in FIG. 1 , and the transverse direction perpendicular to the longitudinal direction of the road (i.e., the x direction) is Figure 2 The vehicle 10 may be equipped with a sensing device for detecting the surrounding environment, such as a camera, a radar and / or a LiDAR. The sensing device may be installed at any position of the vehicle, such as Figure 2 At the left front portion EP1 and the right front portion EP2 of the vehicle 10 shown in FIG.

[0023] The method of the present invention is generally divided into two steps.

[0024] In step 1, the average yaw rate of the target vehicle 30 when turning toward the own lane L2 is calculated.

[0025] First, the yaw angle YA of the target vehicle 30 at the current moment is calculated by the absolute speed of the target vehicle 30 at the current moment. vel , and then calculate the yaw angle difference Δ between the yaw angle of the target vehicle 30 at the current moment and the yaw angle of the previous moment relative to the host vehicle 10 by formula (1): YA Yaw angle YA vel The calculation method of is known and will not be described here.

[0026] Calculate the yaw angle difference Δ by formula (1): YA , because considering the error of the sensor, the yaw angle difference Δ calculated by formula (1) YA Reduces the sensor error to the yaw angle difference Δ YA impact.

[0027] Δ YA =YA vel -(YA prl -YR ego ×Δ t ) (1)

[0028] Among them, YA prl represents the yaw angle of the target vehicle 30 at the last moment, YR ego represents the yaw rate of the vehicle 10, Δ t Indicates the preset time interval, that is, the time interval between the current moment and the previous moment and between the next moment and the current moment.

[0029] Then, the current yaw rate YR of the target vehicle 30 is calculated according to formula (2): tac .

[0030] Y tac =Δ YA ÷Δ t (2)

[0031] Calculate the yaw rate YR of the target vehicle 30 at three consecutive time intervals tac1 , YR tac2 , YR tac3 , and then calculate their average value YR taa That is, the average value YR of the yaw rate of the target vehicle 30 in three consecutive time intervals is calculated according to formula (3): taa .

[0032] Y taa = (YR tac1 +YR tac2 +YR tac3 ) ÷3 (3)

[0033] The average yaw rate YR taa and the preset yaw rate threshold YR tath For comparison, if the average value YR taa Greater than the yaw rate threshold YR tath , then proceed to step 2. Yaw rate threshold YR tath For example, the yaw rate threshold value YR can be changed according to the speed of the target vehicle. For example, the higher the speed, the smaller the yaw rate threshold value. When the speed of the target vehicle is 60 km / h, the yaw rate threshold value YR th Optionally, the yaw rate threshold YR is set to 0.4 rad / s according to the speed of the target vehicle. th It can be set to 0.2rad / s, 0.3rad / s, 0.5rad / s, 0.6rad / s, 0.7rad / s, 0.8rad / s, etc.

[0034] As mentioned above, if the average value YR taa Greater than the yaw rate threshold YR tath , then proceed to step 2. In step 2, the body proportion of the target vehicle 30 entering the lane L2 where the host vehicle 10 is located is calculated.

[0035] First, the predicted yaw angle YA of the target vehicle 30 at the next moment is calculated by formula (4): prn .

[0036] YA prn =(1-K dx )×(YR taa ×Δ YA +YA prl )+K dx ×YA vel (4)

[0037] Among them, K dx is a coefficient that depends on the longitudinal distance between the target vehicle 30 and the host vehicle 10. The closer the distance, the greater the K dx The larger the K dx Can be obtained through experiments. Figure 3 Schematically shows a K according to an embodiment dx The relationship with respect to the longitudinal distance between the target vehicle 30 and the host vehicle 10. For example, when the longitudinal distance between the target vehicle 30 and the host vehicle 10 is 80 meters, K dx Can be 0. When the longitudinal distance is 40 meters, K dx It can be 0.7. Figure 3 About K dx The relationship curve between the longitudinal distance between the target vehicle 30 and the host vehicle 10 is schematic, and different relationship curves may be set according to the characteristics of the driver and the type of vehicle.

[0038] Figure 2 The solid line frame in the figure indicates that the target vehicle 30 has a yaw angle YA relative to the position of the dotted line frame. prn The position after the turn. Through the correction of formula (4), Figure 2 The solid line frame in is substantially close to the actual position of the target vehicle 30 .

[0039] The yaw angle YA obtained by calculation prn The distance Dd between the point P1 of the target vehicle 30 farthest from the lane boundary B1 and the lane boundary B1 is calculated. Various methods can be used to calculate the distance Dd between the point P1 farthest from the lane boundary B1 and the lane boundary B1. prn To calculate the distance Dd. For example, the distance Dd can be calculated in the following way.

[0040] Assuming that the coordinates of the rear midpoint P3 of the target vehicle 30 sensed by the vehicle system are (LatP3, LonP3), and the coordinates of the left front point P1 are (LatP1, LonP1), then the new coordinates (LatP1', LonP1') of the front left point P1 after the target vehicle rotates by an angle A are calculated as follows:

[0041] First, the coordinates of P1 are transformed into coordinates in a coordinate system with P3 as the origin using the following two transformation formulas:

[0042] dx=LonP1-LonP3

[0043] dy=LatP1-LatP3

[0044] Then, use the following two formulas to multiply the coordinates after the transformation origin by a rotation matrix to obtain the rotation YA prn Coordinates after angle:

[0045] dx'=dxcos(YA prn )-dysin(YA prn )

[0046] dy'=dx sin(YA prn )+dycos(YA prn )

[0047] The following two formulas are used to transform the coordinates of P1 after rotation relative to P3 as the origin back to the coordinates relative to the original coordinate origin:

[0048] LatP1'=LonP3+dx'

[0049] LonP1'=LatP3+dy'

[0050] After calculating the new coordinates (LatP1', LonP1') of the left front point P1 of the target vehicle 30, it is easy to calculate the shortest distance Dd between the left front point P1 and the lane boundary B1. The distance Dd can be obtained using any suitable method, which is known and will not be described in detail here.

[0051] After the distance Dd is calculated, the distance Dd between the point P1 of the target vehicle 30 farthest from the lane boundary B1 and the lane boundary B1 and the width W of the target vehicle are calculated by formula (5): obv The ratio R L , that is, the body proportion of the target vehicle 30 entering the lane L2 where the host vehicle 10 is located. By calculating the body proportion, the extent to which the target vehicle 30 invades the lane L2 can be clearly understood, thereby determining whether the host vehicle 10 can continue to cruise normally in the lane L2.

[0052] R L =Dd÷W obv (5)

[0053] The ratio R L Ratio with the preset threshold R LT For comparison, when R L≥ R LT When , it can be considered that the target vehicle 30 will cut into the lane L2 where the host vehicle is located from the adjacent lane L3, so the target vehicle 30 can be selected as the target to be followed by the host vehicle 10. LT Can be determined based on experiments.

[0054] According to one embodiment, the ratio threshold R LT Set to a constant value, such as 0.2, 0.25, 0.3, 0.35. For example, if the ratio threshold R LTis 0.25, then when the distance Dd between the point P1 farthest from the lane boundary B1 in the portion of the target vehicle 30 entering the lane L2 and the lane boundary B1 is greater than or equal to 0.25 times the width of the target vehicle, the target vehicle can be selected as the following target.

[0055] According to another embodiment, the ratio threshold R LT It is set to be related to the speed of the target vehicle. The higher the speed of the target vehicle, the higher the ratio threshold R LT For example, when the speed of the target vehicle is 60 km / h, the ratio threshold RLT is 0.25, and when the speed of the target vehicle is 80 km / h, the ratio threshold RLT is 0.2.

[0056] According to one embodiment, the distance Dd and the width W of the target vehicle are not calculated. obv The ratio R L Instead, the ratio of the distance Dd to the lane width of the host vehicle 10 is calculated, and the ratio is compared with a preset ratio threshold. When the ratio is greater than the ratio threshold, it can be considered that the target vehicle 30 will cut into the host vehicle's lane L2 from the adjacent lane L3, so the target vehicle 30 can be selected as the target to be followed by the host vehicle 10. The ratio threshold R LT Can be determined based on experiments.

[0057] Figure 4 A flow chart of a method for determining whether a vehicle in the adjacent lane L3 cuts into the lane L2 where the host vehicle is located according to an embodiment of the present invention is exemplarily shown.

[0058] In step S1000, the program is started.

[0059] In step S1010, it is detected whether there is a target vehicle in the adjacent lane L3 of the host vehicle 10 in front of the host vehicle 10 and the distance from the host vehicle 10 is less than a preset threshold. If there is, the process proceeds to step S1020.

[0060] In step S1020, according to the above step 1, the average yaw rate YR of the target vehicle detected in step S1010 when turning toward the lane L2 is calculated. taa .

[0061] In the optional step S1030, the average yaw rate YR of the target vehicle is determined. taa Is it greater than a predetermined average yaw rate threshold? If so, proceed to step S1040. If not, return to step S1010.

[0062] In step S1040 , the body ratio of the target vehicle 30 entering the lane L2 where the host vehicle 10 is located is calculated according to the aforementioned step 2.

[0063] In step S1050, it is determined whether the vehicle body ratio calculated in step S1040 is greater than a predetermined ratio threshold value, and if so, the process proceeds to step S1060. If not, the process returns to step S1010.

[0064] In step S1060 , it is determined that the target vehicle will cut into the lane L2 where the host vehicle is located and travel in front of the host vehicle, and an action is taken in the host vehicle 10 to cope with the cutting-in behavior of the target vehicle 30 .

[0065] The action for coping with the cut-in behavior of the target vehicle 30 may include one or more of the following actions:

[0066] (1) highlighting the target vehicle 30 on a display device in the host vehicle 10 to attract the attention of the driver of the host vehicle 10;

[0067] (2) A speaker in the host vehicle 10 may issue a voice reminder to alert the driver that the target vehicle 30 is cutting in front of the host vehicle 10;

[0068] (3) Automatically adjusting the speed of the host vehicle 10 to adapt to the cutting-in behavior of the target vehicle 30;

[0069] (4) Automatic following is performed so that the host vehicle 10 automatically follows the target vehicle 30 and continues to travel in the host lane L2.

[0070] According to another embodiment, after starting the program, it can be first determined whether the host vehicle 10 is following the front vehicle 20. If so, it is detected whether there is a target vehicle whose distance from the host vehicle 10 is less than the distance between the host vehicle 10 and the front vehicle 20 being followed. If there is a target vehicle whose distance from the host vehicle 10 is less than the distance between the host vehicle 10 and the front vehicle 20 being followed, the process proceeds to the above step S1020.

[0071] The following is an illustrative description of specific operations of the vehicle 10 when the vehicle 10 is in a cruising mode (i.e., an automatic driving mode without following other vehicles) and a following mode and a target vehicle 30 cuts into the lane.

[0072] When the host vehicle 10 is in the cruise mode and determines that the target vehicle 30 will cut into the host lane L2 and travel in front of the host vehicle, the host vehicle 10 can automatically switch from the cruise mode to the following mode to automatically follow the target vehicle 30 .

[0073] Optionally, the target vehicle 30 is highlighted on the display device in the vehicle 10, and a dialog box automatically pops up on the display device to remind the driver that the target vehicle 30 has cut in, and ask the driver whether to switch from the cruise mode to the follow mode to follow the target vehicle 30. If the driver replies "yes", the vehicle 10 switches from the cruise mode to the follow mode to follow the target vehicle 30; if the driver replies "no", the vehicle 10 continues to travel in the cruise mode after the target vehicle 30 cuts into the lane L2. Additionally or alternatively, the speaker in the vehicle 10 can issue a voice reminder to remind the target vehicle 30 to cut in and ask whether to follow the target vehicle 30. The driver can indicate whether to switch the driving mode through voice input.

[0074] When the vehicle 10 is in the following mode (for example, following the front vehicle 20 in the lane L2) and determines that the target vehicle 30 will cut into the lane L2 and drive in front of the vehicle, the vehicle 10 can automatically switch the following target from the front vehicle 20 to the target vehicle 30 to automatically follow the target vehicle 30.

[0075] Optionally, the target vehicle 30 is highlighted on the display device in the vehicle 10, and a dialog box automatically pops up on the display device to remind the driver that the target vehicle 30 has cut in, and ask the driver whether to switch the following target to follow the target vehicle 30. If the driver replies "yes", the vehicle 10 switches the following target from the front vehicle 20 to the target vehicle 30 to follow the target vehicle 30; if the driver replies "no", the driving of the vehicle 10 will be taken over by the driver. After taking over, the driver can continue to drive in the lane L2, or the driver can reselect the driving lane and driving mode. Additionally or alternatively, the speaker in the vehicle 10 can issue a voice reminder to remind the target vehicle 30 to cut in, and ask the driver whether to switch the following target to follow the target vehicle 30. The driver can indicate whether to switch the following target through voice input.

[0076] The present invention also provides a machine-readable storage medium on which instructions are stored that can be executed by a computer system to perform the steps of the method according to the present invention. The machine-readable storage medium can be a machine-readable storage device, a machine-readable storage substrate, a memory device, a material composition that affects a machine-readable propagation signal, or a combination of one or more of them.

[0077] The present invention further provides a domain controller, comprising at least one processor and a memory coupled to the at least one processor, wherein the memory stores a computer program, and when the computer program is executed by the at least one processor, the method according to the present invention is implemented.

[0078] The present invention also provides a computer program product, which comprises a computer program. When the computer program is executed by a computer, the computer is caused to execute the method according to the present invention.

[0079] Therefore, although the features of the embodiments of the present invention have been shown, described and pointed out, it is understood that those skilled in the art may make various omissions, substitutions and changes to the form and details of the methods shown and their operations, and the order of steps of the above methods is only exemplary, and it is possible to adjust the steps of the methods of the present invention under the premise of being able to achieve the functions of the present invention. For example, all combinations of method steps that perform substantially the same functions in substantially the same way to achieve the same results are equivalent.

Claims

1. An adaptive cruise control method, comprising: A selection step of selecting a target vehicle (30) in the adjacent lane (L3) in front of the host vehicle (10) that may cut into the host lane (L2); The first calculation step is to calculate the average yaw rate (YR taa ); In the second calculation step, the average yaw rate (YR taa ) calculating the body proportion of the target vehicle (30) entering the lane (L2); A comparison step, comparing the vehicle body ratio with a preset ratio threshold; A determination step, if the body ratio is greater than the ratio threshold, determines that the target vehicle (30) will cut into the lane (L2) and travel in front of the host vehicle, and takes action in the host vehicle (10) to respond to the cutting-in behavior of the target vehicle.

2. The method according to claim 1, wherein the actions include: The target vehicle (30) is highlighted on a display device in the host vehicle (10) to remind the driver that the target vehicle (30) is cutting in front of the host vehicle (10).

3. The method according to claim 1, wherein the actions include: A voice reminder is issued through a speaker in the host vehicle (10) to remind the driver that the target vehicle (30) is cutting in front of the host vehicle (10).

4. The method according to any one of claims 1 to 3, wherein the actions include: The speed of the host vehicle (10) is automatically adjusted to adapt to the cutting-in behavior of the target vehicle (30).

5. The method according to any one of claims 1 to 3, wherein the actions include: The host vehicle (10) automatically follows the target vehicle (30) and continues to travel in the host lane (L2).

6. The method according to any one of claims 1 to 3, further comprising: A judgment step before the selection step: comparing a first distance between the target vehicle (30) and the host vehicle (10) with a second distance between the host vehicle (10) and the front vehicle (20) being followed; if the first distance is smaller than the second distance, the target vehicle (30) is selected as the target vehicle that may cut into the host lane (L2).

7. The method according to any one of claims 1 to 3, further comprising: A judgment step before the selection step: comparing the distance between the target vehicle (30) and the host vehicle (10) with a preset distance threshold; if the distance is less than the distance threshold, selecting the target vehicle (30) as the target vehicle that may cut into the host lane (L2).

8. The method according to any one of claims 1 to 3, wherein: In the second calculation step, the average yaw rate (YR taa ) uses the following formula to calculate the predicted yaw angle (YA) of the target vehicle (30) at the next moment: prn ), and based on the predicted yaw angle (YA prn ) calculates the body proportion of the target vehicle (30) entering the lane (L2), YA prn =(1-K dx )×(YR taa ×Δ YA +YA prl )+K dx ×YA vel Among them, K dx is a coefficient obtained experimentally depending on the longitudinal distance between the target vehicle and the host vehicle (10), Δ YA It is a preset time interval, YA prl represents the yaw angle of the target vehicle (30) at the last moment, YA vel represents the yaw angle YA of the target vehicle (30) at the current moment calculated based on the absolute speed of the target vehicle (30) at the current moment vel .

9. A domain controller, comprising: At least one processor, and a memory coupled to the at least one processor, the memory storing a computer program, which implements the method according to any one of claims 1 to 8 when the computer program is executed by the at least one processor.

10. A computer program product having a computer program stored thereon, wherein when the computer program is executed by a processor, the method according to any one of claims 1 to 8 of the present invention is implemented.

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