ADAPTIVE CONTROL OF AUTOMATIC LANE CHANGE IN THE VEHICLE

Abstract

A method (300) for performing adaptive control of an automatic lane change in a vehicle (100), the method comprising: Locating a target vehicle (200) with a target speed (T) in a target lane (180) at a target distance behind the vehicle (100), wherein the target speed (T) is greater than a speed (S) of the vehicle (100), and the vehicle (100) will enter the target lane (180) based on the automatic lane change; Determine (330) a deceleration rate required by the target vehicle (200) over a braking distance (220, D) which is less than the target distance, in order to equalize its speed (T) and the speed (S) of the vehicle (100); Determine (340) whether the deceleration rate exceeds a threshold deceleration rate, and prohibit (360) automatic lane change based on the fact that the deceleration rate exceeds the threshold deceleration rate; further comprising determining a detection distance (210) as a distance traveled by the target vehicle (200) in a fixed time interval, and determining the braking distance (220, D) as the detection distance (210) and a predefined buffer distance (230) subtracted from the target distance, wherein determining (330) the deceleration rate required by the target vehicle (200) is based on the target velocity (T), which is an initial velocity, the velocity (S) of the vehicle (100), which is a final velocity, and a deceleration distance (D), which is the braking distance, and determining (330) the deceleration rate required by the target vehicle (200) includes calculating S 2 − T 2 2 D contains.

Description

Technical field

[0001] The subject of the disclosure relates to the adaptive control of an automatic lane change in a vehicle. Introduction

[0002] Vehicles (e.g., cars, trucks, construction equipment, agricultural machinery, automated operating systems) are increasingly equipped with sensors that provide information about the vehicle and its surroundings. These sensors (e.g., cameras, radar systems, lidar systems) have enabled the automation of aspects of vehicle operation or even fully autonomous vehicle operation. Lane changing, in which a vehicle switches between two lanes with traffic traveling in the same direction, is one aspect of vehicle operation that has been automated. Automatic lane changing can be part of autonomous driving or semi-autonomous driving (e.g., hands-free driving).

[0003] US 2017 / 0 349 173 A1 describes a procedure for determining the timing of a lane change by a vehicle or a nearby vehicle. It determines that if the distance between a vehicle and a nearby vehicle is outside a first distance threshold, a lane change is permitted. If the distance is within the first distance threshold, a lane change is not permitted. After a lane change has been determined to be not permitted, a lane change that is not permitted is changed to a permitted lane change if the nearby vehicle decelerates or accelerates to move further away from the vehicle than a second distance threshold, even if the distance is still within the first distance threshold.

[0004] US Patent 2017 / 0174262A1 describes a driver assistance device. The device includes a other-vehicle detector, a other-vehicle information acquisition unit, a proximity detector, a proximity controller, and an adjustment unit. The other-vehicle detector detects another vehicle traveling in the second lane. The other-vehicle information acquisition unit gathers information about the size of the other vehicle. The proximity detector outputs a proximity signal when it detects that the other vehicle is within the detection range of the second lane and at a predetermined detection distance from the driver's vehicle. The proximity controller activates a distance control unit when it detects that a turn signal is being used while the distance signal is being output. The adjustment unit increases the detection distance according to the size of the other vehicle.

[0005] Accordingly, the object of the invention is to provide an adaptive control system for automatic lane changing in a vehicle. Description of the invention

[0006] According to a first aspect of the invention, a method for performing adaptive control of an automatic (or automated) lane change in a vehicle includes locating a target vehicle with a target speed in a target lane at a target distance behind the vehicle. The target speed is greater than the vehicle's speed, and the vehicle will enter the target lane based on the automatic lane change. The method also includes determining a deceleration rate that the target vehicle needs to achieve a braking distance shorter than the target distance to match the vehicle's speed, and determining whether the deceleration rate exceeds a threshold deceleration rate. The automatic lane change is prohibited if the deceleration rate exceeds the threshold deceleration rate.The procedure further includes determining a detection distance as the distance traveled by the target vehicle in a fixed time interval, and determining the braking distance as the detection distance and a predefined buffer distance, which are subtracted from the target distance. Determining the braking rate required by the target vehicle is based on the target speed, which is an initial speed, the vehicle's speed, which is a final speed, and a braking distance, which is the braking distance. Determining the braking rate required by the target vehicle involves calculating S2−T22D

[0007] According to one embodiment, the method also includes determining the target distance as a maximum detection range of one or more sensors of the vehicle.

[0008] According to a further embodiment, the method also includes determining the target distance as a distance that is smaller than a maximum detection range of one or more sensors of the vehicle, based on the detection of a following vehicle behind the vehicle.

[0009] According to a further embodiment, the method also includes determining the target distance based on the position of one or more sensors of the vehicle, a distance between the vehicle and the following vehicle, and a width of the following vehicle.

[0010] According to another embodiment, the method also includes determining the target speed as a fixed value above a specified speed limit for the target lane.

[0011] According to another embodiment, the method also includes allowing automatic lane changes based on the fact that the deceleration rate is less than or equal to the threshold deceleration rate.

[0012] According to a second aspect of the invention, a system for performing adaptive control of an automatic lane change in a vehicle comprises one or more sensors for detecting objects behind the vehicle and a processor for locating a target vehicle at a target speed in a target lane at a target distance behind the vehicle. The target speed is greater than the vehicle's speed, and the vehicle will enter the target lane based on the automatic lane change. The processor additionally determines the deceleration rate required by the target vehicle over a braking distance shorter than the target distance to reach the vehicle's speed, determines whether the deceleration rate exceeds a threshold deceleration rate, and prohibits the automatic lane change based on the fact that the deceleration rate exceeds the threshold deceleration rate.The processor is configured to determine a detection distance as the distance traveled by the target vehicle in a specified time period. The processor is configured to determine the braking distance as the detection distance plus a predefined buffer distance subtracted from the target distance. The processor is further configured to determine the braking rate required by the target vehicle based on the target speed, which is the initial speed, the vehicle's speed (100), which is the final speed, and a braking distance, which is the braking distance. The processor is configured to calculate the braking rate required by the target vehicle based on... S2−T22D to determine.

[0013] According to one embodiment, the processor determines the target distance as the maximum detection range of one or more sensors of the vehicle.

[0014] According to another embodiment, the processor determines the target distance as a distance that is smaller than the maximum detection range of one or more sensors of the vehicle, based on the detection of a following vehicle behind the vehicle.

[0015] According to another embodiment, the processor determines the target distance based on the position of one or more sensors of the vehicle, the distance between the vehicle and the following vehicle, and the width of the following vehicle.

[0016] According to another embodiment, the processor determines the target speed as a fixed value above a specified speed limit for the target lane.

[0017] According to another embodiment, the processor allows automatic lane changes based on the fact that the deceleration rate is less than or equal to the threshold deceleration rate.

[0018] The aforementioned features and advantages, as well as further features and advantages of the disclosure, are readily apparent from the following detailed description in conjunction with the accompanying figures. Brief description of the drawings

[0019] Further features, advantages, and details appear only as examples in the following detailed description, which refers to the figures in which: Fig. 1 is a block diagram of a vehicle that includes adaptive control of an automatic lane change; Fig. 2 is a block diagram illustrating the method for performing adaptive control of an automatic lane change according to one or more embodiments; Fig. 3 a process flow of a method for performing adaptive control of an automatic lane change according to one or more embodiments; and Fig. Figure 4 shows an exemplary scenario in which adaptive control of an automatic lane change is carried out according to one or more embodiments. Detailed description

[0020] The following description is merely exemplary and is not intended to limit the present disclosure, its application, or its use. It should be understood that throughout the figures, corresponding reference symbols indicate identical or corresponding parts and features.

[0021] As mentioned earlier, automatic lane changes can be part of a vehicle's autonomous or semi-autonomous operation. Typically, a lane change can be performed when the adjacent lane the vehicle is about to enter is clear of obstacles. This means the vehicle's sensors (e.g., cameras) determine the position of other vehicles or objects within their field of view. If no other vehicles or objects are in the way of the lane change, it is performed. However, under certain circumstances, relying solely on the objects in the field of view to determine whether an automatic lane change is possible can be problematic.For example, during an automatic lane change from one lane to another, a fast-moving vehicle may be just outside the driver's field of vision, even if the vehicle's sensors detect no objects in the second lane. This fast-moving vehicle may be forced to brake excessively (e.g., beyond a predetermined threshold) to avoid a collision caused by the lane change. Embodiments of the systems and methods described herein relate to the adaptive control of an automatic lane change in a vehicle. The adaptive control can prevent an automatic lane change that would otherwise be performed.

[0022] According to an exemplary embodiment, Fig. Figure 1 shows a block diagram of a vehicle incorporating adaptive control of an automatic lane change. The example vehicle is an automobile 101 and is referred to as the subject vehicle 100. The subject vehicle 100 includes several sensors 105. A radar system 110, a camera 120, and a lidar system 130 are shown as rear-facing sensors 105, which are of interest in the automatic lane change scenario according to one or more embodiments. Another radar system 140 is shown as facing forward. According to alternative embodiments, additional sensors 105 may be included, and each of the sensors 105 may be located at different points in or on the subject vehicle 100.

[0023] A controller 150 is also depicted in the subject vehicle 100. The controller 150 can receive raw data or information from one or more sensors 105, individually or according to conventional sensor fusion schemes. The data or information is used to detect objects 170 in the field of view of the sensors 105. The in Fig. The example object 170 shown is another vehicle. The maximum detection range 160 is also shown. This maximum detection range 160 can be based on one of the sensors 105 (e.g., radar system 110) or result from the fusion of two or more sensors 105 (e.g., radar system 110 and camera 120). The lane into which the subject vehicle 100 would move due to the automatic lane change is referred to as the target lane 180 for explanatory purposes. The detection of objects 170 by one or more sensors 105 and the determination of the maximum detection range 160 are not explained in detail here. The detection of object 170 by one or a combination of the sensors 105 is well known, and the embodiments described herein refer to an undetected vehicle and not to a detected object 170.Furthermore, the determination of the maximum detection range 160 for each of the exemplary sensors 105 is known and is assumed to be a known quantity for the controller 150. The modification of the maximum detection range 160 based on a following vehicle 400 (. Fig. 4) is referred to Fig. 4 discussed.

[0024] As with reference to Fig. As described in section 3, the control unit 150 assumes that another vehicle, for explanatory purposes referred to as target vehicle 200 ( Fig. 2) denotes that the target vehicle 200 is located just outside the maximum detection range 160 on the target lane 180. The controller 150 calculates the braking required by this target vehicle 200 to determine whether the automatic lane change should be prohibited. To perform the functionality described herein, the controller 150 may include a processing circuit that may comprise an application-specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or grouped) that executes one or more software or firmware programs, and memory, a combinational logic circuit, and / or other suitable components that provide the described functionality.

[0025] Fig. Figure 2 is a block diagram illustrating the process of performing adaptive control of an automatic lane change according to one or more execution variants. The subject vehicle 100 is shown with a detected object 170 (another vehicle) in front of it. There are no detected objects 170 in the target lane 180. Outside the maximum detection range 160 behind the subject vehicle 100, the controller 150 assumes the presence of a target vehicle 200. As mentioned earlier, the target vehicle 200 is not a detected object 170, but an assumed object used to determine whether an automatic lane change should occur. The controller 150 assumes that the speed at which the target vehicle 200 is traveling is a value Δ above the speed limit (speed = speed limit + Δ). The factors used to determine the value Δ are given with reference to Fig. 3 explained in more detail. Three zones 210, 220, 230 are in Fig. 2 shown.

[0026] The detection zone 210 is a distance that the target vehicle 200 will cover within a defined time period (e.g., 1 second). This defined time period is called the detection time and is the assumed duration for the driver of the target vehicle 200 to recognize that the subject vehicle 100 is changing lanes. The buffer zone 230 is a specific distance from the rear of the subject vehicle 100. The distance of the buffer zone 230 is set depending on the speed of vehicle 100. For example, the buffer zone might be on the order of 2 meters for a relatively low speed and on the order of 20 meters for a relatively high speed of vehicle 100. The initial setting or subsequent refinement of the distance of the buffer zone 230 may be based on experimentation or experience.

[0027] Braking zone 220 is the remaining distance. That is, as mentioned earlier, the controller 150 knows the maximum detection range 160. Thus, the controller 150 can determine braking zone 220 by subtracting the detection zone 210 (derived from the assumed speed of the target vehicle 200) and the buffer zone 230 from the maximum detection range 160. This braking zone 220 is the distance within which the target vehicle 200 must reduce its speed to the speed of the target vehicle 100 known to the controller 150. The controller 150 determines whether the deceleration rate that must occur within braking zone 220 is greater than a threshold deceleration rate. That is, the control unit 150 determines whether the target vehicle 200 needs to brake too hard (according to the specified threshold) to match its speed to the speed of the subject vehicle 100 before it reaches the buffer zone 230.If so, then control unit 150 determines that the automatic lane change should not be performed.

[0028] Fig. 3 is a process flow 300 of a method for performing adaptive control of an automatic lane change according to one or more embodiments. The process steps described for process flow 300 can be performed by the controller 150. Process flow 300 can be initiated when an automatic lane change is proposed by an existing autonomous or semi-autonomous driving system. In various embodiments, the process steps in blocks 310 and 320 can be performed regularly on a periodic basis or on an event-based basis (e.g., each time the speed of the subject vehicle 100 changes). In block 310, the determination of the maximum detection range 160 is performed based on the sensors 105 used (e.g., one or more radar systems 110) and the speed of the vehicle 100 under investigation. As with reference to Fig. As explained in more detail in section 4, the known value of the maximum detection range 160 for a specific sensor 105 can be changed if the field of view of the sensor 105 is impaired (e.g. by following the vehicle 400 in Fig. 4) If an automatic lane change is being considered (i.e., it has been suggested by an autonomous or semi-autonomous driving system), then determining the maximum detection range 160 is also determining the distance to a target vehicle 200, which is an undetected vehicle assumed to be just outside the field of view of the sensors 105 used.

[0029] In block 320, determining the speed of the target vehicle 200 can, as mentioned previously, be based on the speed limit. For example, the speed of the target vehicle 200 can be assumed to be (speed limit + Δ), and Δ can be chosen to be, for example, 15 mph. The value of Δ can be adjusted, for example, due to weather conditions or other factors. In block 330, procedure 300 involves calculating the deceleration rate required by the target vehicle 200 in the braking zone 220. The length of the braking zone 220 is determined, as described above, by subtracting the lengths of the detection zone 210 and the buffer zone 230 from the maximum detection range 160. The target vehicle must decelerate from the determined speed of the target vehicle 200 (from block 320) T to the speed of the subject vehicle 100 S over the length of the braking zone 220 D. The deceleration rate is therefore given by: Deceleration rate = S2−T22D

[0030] In block 340, a check is performed to determine whether the deceleration rate calculated with EQ.1 is greater than a threshold deceleration rate. The threshold deceleration rate can be chosen, for example, as 0.2 g (g = 9.81 meters / second). 2 If the required deceleration rate of the (hypothetical) target vehicle 200 in braking zone 220 is less than or equal to the threshold (according to the check in block 340), then procedure 300 includes proceeding with the automatic lane change in block 350. If, on the other hand, the deceleration rate determined in block 330 exceeds the threshold (in block 340), then procedure 300 includes prohibiting the planned automatic lane change in block 360.

[0031] Fig. Figure 4 shows an example scenario for which the maximum detection range is 160 (at block 310, Fig. 3) is modified to perform adaptive control of an automatic lane change according to one or more embodiments. Fig. Figure 4 shows the maximum detection range of 160 according to sensor 105 (located in the center of the rear of the subject vehicle 100), which is used for automatic lane changing. If no following vehicle 400 were within the maximum detection range of 160 behind the subject vehicle 100, this maximum detection range of 160 would be reached at block 310. Fig. 3, can be used. However, if, as in the one in Fig. In the example scenario shown in 4, where a following vehicle 400 is located behind the subject vehicle 100, the maximum detection range 160 is reduced to the distance MD as part of the execution in block 310.

[0032] Factors influencing the distance MD (i.e., the modified maximum detection range 160) include the distance between the subject vehicle 100 and the following vehicle 400, the width W of the following vehicle 400, and the position of one or more sensors 105 on the subject vehicle 100 used to detect objects behind the subject vehicle 100. For illustrative purposes, in the example scenario, it is assumed that both the subject vehicle 100 and the following vehicle 400 are centered in the lane. Therefore, the distance from the center of the subject vehicle 100, where the sensor 105 is located, to the corner of interest of the target vehicle 200 is given by (L+W / 2). The corner of interest is the left corner of the target vehicle 200 if the target lane 180 is to the left of the subject vehicle 100, and the corner of interest is the right corner of the target vehicle 200 if the target lane is to the right of the subject vehicle 100.The value of L is based on knowledge of the lane width and an assumed width for the target vehicle 200 (e.g., it can be assumed that the target vehicle 200 is in the middle of the target lane 180).

[0033] How Fig. As shown in Figure 4, the value of the distance MD can be determined from equations for a right-angled triangle based on the angle α and the distance between sensor 105 and the corner of interest of the target vehicle 200. Thus, the distance MD can be given by (L + W / 2)(tan α). As the distance between the subject vehicle 100 and the following vehicle 400 increases, the value of the angle α increases. Therefore, all other things being equal, the distance MD will increase. As the width W of the following vehicle 400 increases, the value of the angle α decreases. Therefore, all other things being equal, the distance MD will decrease. If sensor 105 is moved from its current center position to the left side of the rear bumper of subject vehicle 100, the angle α increases. Furthermore, (L + W / 2) would decrease by the distance R between the center of subject vehicle 100 and the left side of the rear bumper.The distance MD therefore increases with (L + W / 2 - R) * (tan α). However, in the case in . Fig. In the exemplary scenario 4, if sensor 105 were moved to the right side of the rear bumper of the affected vehicle 100, the following vehicle 400 would block even more of the sensor 105's field of view and the distance MD would decrease significantly.

Claims

[1] A method (300) for performing adaptive control of an automatic lane change in a vehicle (100), the method comprising: Localizing a target vehicle (200) having a target speed (T) in a target lane (180) at a target distance behind the vehicle (100), wherein the target speed (T) is greater than a speed (S) of the vehicle (100), and the vehicle (100) will enter the target lane (180) based on the automatic lane change; Determining (330) a deceleration rate required by the target vehicle (200) over a braking distance (220, D) less than the target distance in order to equalize its speed (T) and the speed (S) of the vehicle (100); Determining (340) whether the deceleration rate exceeds a threshold deceleration rate and prohibiting (360) the automatic lane change based on the deceleration rate exceeding the threshold deceleration rate; further comprising determining a detection distance (210) as a distance traveled by the target vehicle (200) in a fixed period of time, and determining the braking distance (220, D) as the detection distance (210) and a predefined buffer distance (230) which are subtracted from the target distance, wherein determining (330) the deceleration rate required by the target vehicle (200) is based on the target speed (T), which is an initial speed, the speed (S) of the vehicle (100), which is a final speed, and a distance (D) for deceleration, which is the braking distance, and determining (330) the deceleration rate required by the target vehicle (200) comprises calculating S2−T22D contains. [2] The method (300) of claim 1, further comprising determining (310) the target distance as a maximum detection range (160) of one or more sensors (105) of the vehicle (100). [3] The method (300) of claim 1, further comprising determining (310) the target distance as a distance (MD) less than a maximum detection range (160) of one or more sensors (105) of the vehicle (100) based on detecting a following vehicle (400) behind the vehicle (100), and determining the target distance based on a location of the one or more sensors (105) of the vehicle (100), a distance between the vehicle (100) and the following vehicle (400), and a width (W) of the following vehicle (400). [4] The method (300) of claim 1, further comprising determining (320) the target speed (T) as a fixed value above a specified speed limit for the target lane (180). [5] A system for performing adaptive control of an automatic lane change in a vehicle (100), the system comprising: one or more sensors (105) configured to detect objects (170) behind the vehicle (100); and a processor (150) configured to locate a target vehicle (200) having a target speed (T) in a target lane (180) at a target distance behind the vehicle (100), wherein the target speed (T) is greater than a speed (S) of the vehicle (100) and the vehicle (100) will move into the target lane (180) based on the automatic lane change, to determine (330) a deceleration rate required by the target vehicle (200) over a braking distance (220, D) less than the target distance to equalize its speed (T) to the speed (S) of the vehicle (100), to determine (340) whether the deceleration rate exceeds a threshold deceleration rate, and to prohibit (340) the automatic lane change based on the deceleration rate exceeding the threshold deceleration rate; wherein the processor (150) is configured to determine a detection distance (210) as a distance traveled by the target vehicle (200) in a specified period of time, wherein the processor (150) is configured to determine the braking distance (220, D) as the detection distance (210) and a predefined buffer distance (230) which are subtracted from the target distance, wherein the processor (150) is configured to determine the deceleration rate required by the target vehicle (200) based on the target speed (T), which is an initial speed, the speed (S) of the vehicle (100), which is a final speed, and a distance (D) for deceleration, which is the braking distance, and wherein the processor (150) is configured to determine the deceleration rate required by the target vehicle (200) based on calculating S2−T22D to determine (330). [6] The system of claim 5, wherein the processor (150) is configured to determine the target distance as a maximum detection range (160) of one or more sensors (105) of the vehicle (100). [7] The system of claim 5, wherein the processor (150) is configured to determine the target distance as a distance (MD) less than a maximum detection range (160) of one or more sensors (105) of the vehicle (100) based on a following vehicle (400) being detected behind the vehicle (100), and wherein the processor (150) is configured to determine the target distance based on a location of the one or more sensors (105) of the vehicle (100), a distance between the vehicle (100) and the following vehicle (400), and a width (W) of the following vehicle (400). [8] The system of claim 5, wherein the processor (150) is configured to determine the target speed (T) as a fixed value above a specified speed limit for the target lane (180).

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