Method, device, electronic device and storage medium for determining vehicle driving safety

Abstract

An embodiment of the present disclosure discloses a method, apparatus, electronic device, and storage medium for determining vehicle driving safety. The method includes: determining a maximum value among the body width of a tractor and the widths of each trailer towed by the tractor as an initial width; processing the body width of the tractor based on a reference dimension and / or the initial width to obtain a target width of the tractor, where the target width is greater than the initial width, and the reference dimension includes at least one of a preset safety distance and a target tracking deviation; and determining whether the tractor towing each trailer can safely travel along the reference trajectory according to the target width. Without the need to determine the poses of each trailer, the evaluation of vehicle driving safety is achieved.

Description

Technical Field

[0001] The present disclosure relates to the field of autonomous driving technology, and in particular, to a method, apparatus, electronic device, and storage medium for determining vehicle driving safety. Background Art

[0002] With the accelerating development of modernization, the landing applications of intelligent connected vehicles in various scenarios such as large industrial parks, logistics parks, airports, etc. are increasing day by day. The increasingly unmanned trend has put forward new requirements for the driving safety of vehicles in such parks.

[0003] In order to improve transportation efficiency, an unmanned tractor usually towes multiple trailers. When planning the path of an unmanned tractor with trailers, it is necessary to consider the kinematic characteristics of the tractor and the trailers, predict the inner cut of multiple trailers, and avoid obstacles that may collide with the trailers in advance. However, due to limitations of factors such as sensor performance, cost, mechanical structure, and power supply, sensors such as positioning or inertial navigation are generally not installed on the trailers, resulting in the inability to obtain the specific pose (including position and heading) of the trailers, which poses a great challenge to the safety of unmanned vehicles towing multiple trailers. In addition, in the field of unmanned logistics, the tractor needs to flexibly mount trailers of different sizes and different numbers, which further increases the difficulty of ensuring the collision safety of multiple trailers.

[0004] Therefore, how to achieve the driving safety of unmanned vehicles without obtaining the pose information of each trailer is of great practical significance for breaking through the key bottleneck of the actual landing application of unmanned logistics vehicles. Summary of the Invention

[0005] In order to solve the above technical problems or at least partially solve the above technical problems, embodiments of the present disclosure provide a method, apparatus, electronic device, and storage medium for determining vehicle driving safety, which realizes the evaluation of vehicle driving safety without determining the pose of each trailer, and this method is applicable to vehicles composed of trailers of different sizes and / or different numbers.

[0006] In a first aspect, embodiments of the present disclosure provide a method for determining vehicle driving safety, the method comprising:

[0007] Determine the maximum value of the body width of the tractor and the widths of each trailer towed by the tractor as the initial width;

[0008] Process the body width of the tractor based on the reference dimension and / or the initial width to obtain the target width of the tractor, where the target width is greater than the initial width, and the reference dimension includes at least one of a preset safety distance and a target tracking deviation, and the target tracking deviation is the maximum value among the steady-state tracking deviations between the driving trajectories of the trailers and the driving trajectory of the tractor when the tractor travels along the reference trajectory;

[0009] Determine whether the tractor towing the trailers can travel safely along the reference trajectory according to the target width.

[0010] In a second aspect, an embodiment of the present disclosure further provides a vehicle driving safety determination device, which includes:

[0011] A first determination module, configured to determine the maximum value among the body width of the tractor and the widths of the trailers towed by the tractor as the initial width;

[0012] A second determination module, configured to process the body width of the tractor based on the reference dimension and / or the initial width to obtain the target width of the tractor, where the target width is greater than the initial width, and the reference dimension includes at least one of a preset safety distance and a target tracking deviation, and the target tracking deviation is the maximum value among the steady-state tracking deviations between the driving trajectories of the trailers and the driving trajectory of the tractor when the tractor travels along the reference trajectory;

[0013] A third determination module, configured to determine whether the tractor towing the trailers can travel safely along the reference trajectory according to the target width.

[0014] In a third aspect, an embodiment of the present disclosure further provides an electronic device, where the electronic device includes: one or more processors; a storage device for storing one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors implement the vehicle driving safety determination method as described above.

[0015] In a fourth aspect, an embodiment of the present disclosure further provides a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the vehicle driving safety determination method as described above is implemented.

[0016] The vehicle driving safety determination method provided by the embodiment of the present disclosure realizes the evaluation of vehicle driving safety without determining the poses of the trailers, and this method is applicable to vehicles with trailers of different sizes and / or different numbers of trailers. Description of the Drawings

[0017] In combination with the accompanying drawings and with reference to the following specific embodiments, the above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic and the original components and elements are not necessarily drawn to scale.

[0018] Figure 1 It is a flowchart of a method for determining vehicle driving safety in an embodiment of the present disclosure;

[0019] Figure 2 It is a schematic diagram of expanding the body width of a tractor in an embodiment of the present disclosure;

[0020] Figure 3 It is a schematic diagram of expanding the body width of a tractor in an embodiment of the present disclosure;

[0021] Figure 4 It is a schematic diagram of a tractor towing a full trailer along a reference trajectory in an embodiment of the present disclosure;

[0022] Figure 5 It is a schematic diagram of a tractor towing a semi-trailer along a reference trajectory in an embodiment of the present disclosure;

[0023] Figure 6 It is a schematic diagram of a tractor towing multiple full trailers along an arc-shaped reference trajectory in an embodiment of the present disclosure;

[0024] Figure 7 It is a schematic diagram of a sampling point on a reference trajectory in an embodiment of the present disclosure;

[0025] Figure 8 It is a schematic diagram of the turning process of a tractor towing multiple trailers in an embodiment of the present disclosure;

[0026] Figure 9 It is a schematic diagram of the motion model of the rear axle turning of the first full trailer in an embodiment of the present disclosure;

[0027] Figure 10 It is a schematic diagram of the motion model of a tractor towing a semi-trailer along a curve in an embodiment of the present disclosure;

[0028] Figure 11 It is a schematic diagram of the motion model of a tractor towing a semi-trailer along a curve in an embodiment of the present disclosure;

[0029] Figure 12 It is a schematic diagram of the motion model of a tractor towing a semi-trailer along a curve in an embodiment of the present disclosure;

[0030] Figure 13Schematic diagram of a tractor turning left and right along a reference trajectory in an embodiment of the present disclosure;

[0031] Figure 14 Schematic diagram of expanding the body width of a tractor in an embodiment of the present disclosure;

[0032] Figure 15 Schematic diagram of the structure of a vehicle driving safety determination device in an embodiment of the present disclosure;

[0033] Figure 16 Schematic diagram of the structure of an electronic device in an embodiment of the present disclosure. Detailed implementation manners

[0034] Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although some embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Instead, these embodiments are provided to more thoroughly and completely understand the present disclosure. It should be understood that the drawings and embodiments of the present disclosure are only for illustrative purposes and are not used to limit the protection scope of the present disclosure.

[0035] It should be noted that concepts such as "first" and "second" mentioned in the present disclosure are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence relationship of the functions performed by these devices, modules or units.

[0036] The names of the messages or information exchanged between multiple devices in the embodiments of the present disclosure are only for illustrative purposes and do not limit the scope of these messages or information.

[0037] Figure 1 Flowchart of a vehicle driving safety determination method in an embodiment of the present disclosure. This method can be executed by a vehicle driving safety determination device, which can be implemented in software and / or hardware, and the device can be configured in an electronic device.

[0038] As Figure 1 shown, the method specifically includes the following steps:

[0039] Step 110: Determine the maximum value among the body width of the tractor and the widths of each trailer towed by the tractor as the initial width.

[0040] For example, if the tractor tows three trailers, the body width of the tractor is 1 m, and the widths of the three trailers are all 2 m, then 2 m is determined as the initial width. If the body width of the tractor is 3 m and the widths of the three trailers are all 2 m, then 3 m is determined as the initial width.

[0041] That is, the initial width wmax = max(w0, w1, w2 …… w N ), where w0 represents the body width of the tractor, w1 represents the width of the first trailer, w2 represents the width of the second trailer, and w N represents the width of the Nth trailer.

[0042] Step 120: Process the body width of the tractor based on the reference dimension and / or the initial width to obtain the target width of the tractor.

[0043] Among them, the target width is greater than the initial width, the reference dimension includes at least one of a preset safety distance and a target tracking deviation, and the target tracking deviation is the maximum value among the steady-state tracking deviations between the driving trajectories of the trailers and the driving trajectory of the tractor when the tractor travels along the reference trajectory.

[0044] Optionally, processing the body width of the tractor based on the reference dimension and / or the initial width to obtain the target width of the tractor includes:

[0045] If the initial width is greater than the body width of the tractor, perform a first expansion on the body width of the tractor to make it equal to the initial width; then perform a second expansion on the initial width based on the reference dimension to obtain the target width. If the initial width is equal to the body width of the tractor, directly perform a second expansion on the body width (i.e., the initial width) based on the reference dimension to obtain the target width.

[0046] Exemplarily, performing a second expansion on the initial width based on the reference dimension to obtain the target width includes:

[0047] Expand the initial width based on the preset safety distance so that the expanded third width is the sum of the initial width and the preset safety distance;

[0048] Expand the third width based on the target tracking deviation so that the expanded fourth width is the sum of the third width and the target tracking deviation.

[0049] Generally speaking, when the body width of the tractor is less than the width of a certain trailer, the body width of the tractor is expanded three times in total. After the first expansion, the body width of the tractor is equal to the width of the widest trailer. After the second expansion, the body width of the tractor is equal to the sum of the width of the widest trailer and the preset safety distance. After the third expansion, the body width of the tractor is equal to the sum of the width of the widest trailer, the preset safety distance, and the target tracking deviation.

[0050] It can be understood that any one or any two of the above three expansions can also be performed only on the body width of the tractor, and it is not limited to necessarily performing the above three expansions.

[0051] When the vehicle is traveling on a straight road, the center of the body width of the tractor can be used as a reference point, and the dimension to be expanded can be evenly expanded on both sides of the reference point so that the widths on both sides of the reference point are equal. As Figure 2 shown in a schematic diagram of expanding the body width of the tractor, where label 210 represents the body width of the tractor, label 211 represents the center of the body width of the tractor, that is, the reference point, label 220 represents the width of the widest trailer, label 230 represents 0.5 times the preset safety distance, and label 240 represents 0.5 times the target tracking deviation. Usually, when the tractor is towing a trailer and traveling on a straight road, the target tracking deviation is 0.

[0052] When the vehicle is traveling on a curve, the center of the body width of the tractor can be used as a reference point, and the difference between the preset safety distance and the width of the widest trailer can be evenly expanded on both sides of the reference point, and the target tracking deviation can be expanded in the inward tangent direction of the driving trajectory of the tractor (because when traveling on a curve, the trailer is prone to shift in the inward tangent direction of the driving trajectory of the tractor, and such expansion is beneficial for more accurate collision prediction). As Figure 3 shown, where label 310 represents the body width of the tractor, label 311 represents the center of the body width of the tractor, that is, the reference point, label 320 represents the width of the widest trailer, label 330 represents 0.5 times the preset safety distance, and label 340 represents the target tracking deviation.

[0053] Generally speaking, if the reference dimension includes a preset safety distance and a target tracking deviation, and the reference trajectory is a circular arc trajectory with a set curvature and in a clockwise direction, the processing of the body width of the tractor based on the reference dimension and the initial width to obtain the target width of the tractor includes:

[0054] Using the center of the body width of the tractor as a reference point, expanding the same width on both sides of the reference point transversely to obtain the first width of the expanded tractor, and the first width is the sum of the initial width and the preset safety distance; continuing to expand the first width in the direction close to the center of the reference trajectory to obtain the second width of the expanded tractor, and the second width is the sum of the initial width, the preset safety distance, and the target tracking deviation.

[0055] By expanding the vehicle body width of the tractor by combining the maximum value of the steady-state tracking deviation between the driving trajectories of the trailers and the driving trajectory of the tractor when the tractor travels along the reference trajectory, the actual width of each trailer, and a preset safety distance, it is beneficial for predicting the road passability, and the purpose of avoiding the risk of collision between the obstacles cutting into the road network and any trailer in various driving scenarios and improving the driving safety can be achieved.

[0056] It can be understood that when the reference trajectory is an arc trajectory with a certain curvature, when the tractor travels along the reference trajectory, there are different steady-state tracking deviations between the driving trajectories of the trailers and the driving trajectory of the tractor (there is a one-to-one correspondence between the trailer and the steady-state tracking deviation, that is, each trailer corresponds to a steady-state tracking deviation). The steady-state tracking deviation between the driving trajectory of some trailers and the driving trajectory of the tractor is small (for example, the trailers close to the tractor), and the steady-state tracking deviation between the driving trajectory of some trailers and the driving trajectory of the tractor is large (for example, the trailers far from the tractor). Therefore, for conservative estimation, when performing collision prediction, the vehicle body width of the tractor is expanded by using the maximum value of the steady-state tracking deviations corresponding to each trailer (i.e., the target tracking deviation). The calculation method of the steady-state tracking deviation corresponding to each trailer is given in the following embodiments.

[0057] When the reference trajectory is a straight-line trajectory, when the tractor travels along the reference trajectory, the driving trajectories of the trailers approximately coincide with the driving trajectory of the tractor. At this time, each steady-state tracking deviation is small and can be ignored, that is, it is considered that each steady-state tracking deviation is 0 at this time.

[0058] Step 130: Determine whether the tractor towing the trailers can safely travel along the reference trajectory according to the target width.

[0059] Optionally, regarding the target width as the actual width of the tractor, predict whether there is a risk of collision with other obstacles near the reference trajectory when the tractor with the target width travels along the reference trajectory. If not, it is determined that the tractor towing the trailers can safely travel along the reference trajectory. If there is a risk of collision, it is determined that the tractor towing the trailers cannot safely travel along the reference trajectory.

[0060] The following is the calculation process of the above steady-state tracking deviation in combination with the kinematic model when the tractor tows the trailer and travels along the reference trajectory:

[0061] In order to accurately determine the deviation between the driving trajectory of the trailer and that of the tractor, the driving trajectory of the center of the rear axle of the tractor is determined as the driving trajectory of the tractor. If the trailer is a semi-trailer, the driving trajectory of the center of the rear axle of the trailer is determined as the driving trajectory of the trailer. At this time, the steady-state tracking deviation is the deviation between the driving trajectory of the center of the rear axle of the trailer and that of the center of the rear axle of the tractor. Assume that the tractor is towing two semi-trailers. The deviation between the driving trajectory of the center of the rear axle of the first semi-trailer and that of the center of the rear axle of the tractor is the steady-state tracking deviation corresponding to the first semi-trailer, and the deviation between the driving trajectory of the center of the rear axle of the second semi-trailer and that of the center of the rear axle of the tractor is the steady-state tracking deviation corresponding to the second semi-trailer. That is, each trailer corresponds to a steady-state tracking deviation, and there is a one-to-one correspondence between the trailer and the steady-state tracking deviation. When expanding the body width of the tractor, the maximum value in the steady-state tracking deviation is referred to, that is, the target tracking deviation.

[0062] If the trailer is a full trailer, the key components affecting the driving trajectory of the trailer include the front axle and the rear axle. Therefore, it is necessary to jointly determine the driving trajectory of the full trailer by combining the driving trajectory of the center of the front axle and that of the center of the rear axle. At this time, the steady-state tracking deviation needs to be jointly determined by combining the first deviation between the driving trajectory of the center of the front axle of the trailer and that of the center of the rear axle of the tractor, and the second deviation between the driving trajectory of the center of the rear axle of the trailer and that of the center of the rear axle of the tractor. For example, the average value of the first deviation and the second deviation can be determined as the steady-state tracking deviation, or the larger value of the first deviation and the second deviation can be determined as the steady-state tracking deviation.

[0063] Further, referring to Figure 4 a schematic diagram of a tractor towing a full trailer traveling along a reference trajectory as shown, the steady-state tracking deviation can be determined according to the reference distance R O between the center of the rear axle of the tractor and the center O of the reference trajectory, the first distance R 1f (i.e., the first turning radius of the front axle of the trailer) between the center of the front axle of the trailer and the center O, and the second distance R1 (i.e., the second turning radius of the rear axle of the trailer) between the center of the rear axle of the trailer and the center O. For example, determine the difference between the reference distance R O and the first distance R 1f , and the difference between the reference distance R O and the second distance R1, and determine the larger of these two differences as the steady-state tracking deviation between the driving trajectory of the first trailer and that of the tractor.

[0064] Correspondingly, referring to Figure 5A schematic diagram showing a tractor towing a semi-trailer along a reference trajectory, where the reference distance R between the center of the rear axle of the tractor and the center O of the reference trajectory can be used O and the third distance R1 between the center of the rear axle of the trailer and the center O (i.e., the third turning radius of the rear axle of the trailer) to determine the steady-state tracking deviation. For example, to determine the reference distance R O and the difference between the third distance R1, and this difference is determined as the steady-state tracking deviation between the driving trajectory of the first trailer and the driving trajectory of the tractor.

[0065] It can be understood that when the tractor is towing a trailer along Figure 4 or Figure 5 the reference trajectory shown, the accurate tracking deviation of the trailer can only be determined when the driving state of the trailer reaches a stable state. For example, when the tractor is towing multiple trailers and enters a loop from a straight road, when a certain trailer is in the state of transitioning from a straight road to a loop, the turning radius of the front axle of this trailer is constantly changing, and it is considered that the stable state has not been reached at this time. When the change amount of the turning radius of the front axle of the trailer is less than the threshold value, it is considered that the front axle of the trailer has reached a stable state. Based on the turning radius at this time, the accurate tracking deviation can be determined, and this tracking deviation is called the steady-state tracking deviation. Therefore, the steady-state tracking deviation described in the embodiments of the present disclosure refers to the deviation between the driving trajectory of the trailer and the driving trajectory of the tractor under the stable state.

[0066] Generally speaking, the vehicle driving safety determination method further includes:

[0067] When each trailer is a full trailer, based on the kinematic model when the tractor is towing each trailer along the reference trajectory, determine the first turning radius between the center of the front axle of each trailer and the center of the reference trajectory, and the second turning radius between the center of the rear axle of each trailer and the center of the reference trajectory; based on the first turning radius, the second turning radius, and the reference radius, determine the steady-state tracking deviation between the driving trajectory of each trailer and the driving trajectory of the tractor;

[0068] When each trailer is a semi-trailer, based on the kinematic model when the tractor is towing each trailer along the reference trajectory, determine the third turning radius between the center of the rear axle of each trailer and the center of the reference trajectory; based on the third distance and the reference radius, determine the steady-state tracking deviation between the driving trajectory of each trailer and the driving trajectory of the tractor.

[0069] Refer to the schematic diagram of a tractor towing multiple full trailers along an arc-shaped reference trajectory as shown in Figure 6 , and in combination with Figure 6 mark and explain the dimension information of the trailer. Among them, l fr0is the wheelbase of the tractor, w0 is the body width of the tractor, and v0 is the speed at the center of the rear axle of the tractor. Let the connection point between the tractor and the front axle of the first trailer be point H0, and l h is the distance from the center of the rear axle of the tractor to the connection point (point H0).

[0070] When multiple trailers are mounted, assume the number of trailers is N (N ≥ 1). For the first full trailer, l fr1 is the wheelbase of the trailer, w1 is the width of the trailer, and l b,1 is the distance from the center of the front axle of the trailer to the connection point (point H0), and v1 is the speed at the center of the rear axle of the first trailer.

[0071] For the nth trailer (n = 2,..., N), l frn is the wheelbase of the trailer, w n is the width of the trailer, and v n is the speed at the center of the rear axle of the trailer. Let the connection point between the (n - 1)th trailer and the nth trailer be point H n-1 point, then l b,n is the distance from the center of the front axle of the nth trailer to the connection point (point H n-1 point). l h,n-1 is the distance from the center of the rear axle of the (n - 1)th trailer to the connection point (point H n-1 point).

[0072] The size information of the trailer can be obtained through actual measurement. The solution provided by the embodiments of the present disclosure is applicable to the scenario of mounting multiple trailers with different sizes.

[0073] The purpose of the present disclosure is to evaluate the collision safety of a vehicle with multiple trailers on a given reference trajectory. Therefore, K sampling points are obtained at equal intervals on the reference trajectory. For the kth sampling point (k = 1, 2,..., K), the reference radius R r,k and the reference speed v r,k can be obtained here, as shown in the appendix Figure 7 . Generally, the speed at the first discrete point k on the reference trajectory is determined as the reference speed v0 of the center of the rear axle of the tractor, and the reference radius corresponding to the first discrete point k is determined as the reference distance R0 between the center of the rear axle of the tractor and the center of the circle corresponding to the first discrete point k. The reference trajectory consists of multiple discrete points, and the first discrete point k is one of the multiple discrete points; the yaw rate of the tractor is determined according to the reference speed v0 and the reference distance R0

[0074] Assume that the tractor-trailer makes a planar motion in the horizontal plane, and the relative sliding between the wheels and the ground is ignored. The earth coordinate system is OXY, where the X-axis points to the due east direction and the Y-axis points to the due north direction. To simplify the motion analysis, a single-axis bicycle model is used in the embodiments of the present disclosure. The schematic diagram of the turning process of the tractor with multiple trailers attached is shown in the appendix Figure 8 as follows. In the figure, δ f is the front-wheel steering angle of the tractor, and θ0 is the heading angle of the tractor.

[0075] For the first trailer, θ 1f is the heading angle of the front axle of the trailer, and θ1 is the heading angle of the rear axle of the trailer. At this time, the angle between the tractor and the front axle of the trailer is The angle between the heading of the front axle and the heading of the rear axle of the first trailer is v 1f is the speed at the center of the front axle of the first trailer, and v1 is the speed at the center of the rear axle of the first trailer.

[0076] For the nth trailer, θ nf is the heading angle of the front axle of the trailer, and θ n is the heading angle of the rear axle of the trailer. At this time, the angle between the heading of the rear axle of the (n - 1)th trailer and the heading of the front axle of the nth trailer is The angle between the heading of the front axle and the heading of the rear axle of the nth trailer is v nf is the speed at the center of the front axle of the nth trailer, and v n is the speed at the center of the rear axle of the nth trailer.

[0077] Next, analyze the motion states of the tractor and each full trailer during the turning process to obtain the steady-state tracking deviation of each full trailer.

[0078] Since the tractor can accurately follow the reference trajectory, in the solution of the embodiments of the present disclosure, the reference trajectory is directly determined as the driving trajectory of the tractor, that is, it is considered that the tractor can strictly follow the reference trajectory. On this basis, the tracking deviation of each trailer relative to the driving trajectory of the tractor can be considered as the tracking deviation of each trailer relative to the reference trajectory.

[0079] The reference radius at each discrete point of the reference trajectory (the reference radius refers to the distance between each discrete point and the center of the reference trajectory) and the reference speed can be obtained in advance. For example, the reference radius can be measured in advance, and the reference speed can be manually set according to experience or obtained by statistically analyzing historical driving speeds. The reference radius at the reference trajectory point k is determined as the reference distance R0 between the center of the rear axle of the tractor and the center of the circle corresponding to the reference trajectory point k, and the reference speed at the reference trajectory point k is determined as the driving speed v0 of the tractor at the reference trajectory point k. That is, for any discrete reference trajectory point k, there is the following relational expression (1):

[0080] R0 = R r,k , v0 = v r,k (1)

[0081] At this time, the yaw rate of the tractor can be calculated by the following formula (2):

[0082]

[0083] The above process can be summarized as follows: The speed at the first discrete point k on the reference trajectory is determined as the reference speed v0 of the center of the rear axle of the tractor, and the reference radius corresponding to the first discrete point k is determined as the reference distance R0 between the center of the rear axle of the tractor and the center of the circle corresponding to the first discrete point k. The reference trajectory consists of multiple discrete points, and the first discrete point k is one of the multiple discrete points; the yaw rate ·0 of the tractor is determined according to the reference speed v0 and the reference distance R0.

[0084] Exemplarily, determining the first turning radius between the center of the front axle of each trailer and the center of the circle of the reference trajectory, and the second turning radius between the center of the rear axle of each trailer and the center of the circle of the reference trajectory based on the kinematic model (as shown in Figure 8 ) when the tractor is towing each trailer along the reference trajectory includes the following steps:

[0085] Step 1. According to the reference speed v0, the yaw rate of the tractor the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer the distance l from the center of the rear axle of the tractor to the connection point H0 with the first trailer h and the distance l from the center of the front axle of the first trailer to the connection point H0 b,1 determine the speed v 1f of the center of the front axle of the first trailer and the yaw rate

[0086] Reference Figure 8As shown, the speed v of the center of the front axle of the first trailer 1f can be determined by the following relation (3):

[0087]

[0088] The rate of change of the heading angle of the front axle of the first trailer can be determined by the following relation (4):

[0089]

[0090] A more specific summary of the above process is: according to the reference speed v0, the rate of change of the heading angle of the tractor the included angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer the distance l from the center of the rear axle of the tractor to the connection point H0 with the first trailer h determine the speed v of the center of the front axle of the first trailer 1f ; according to the reference speed v0, the included angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer the rate of change of the heading angle of the tractor the distance l from the center of the rear axle of the tractor to the connection point with the first trailer h and the distance l from the center of the front axle of the first trailer to the connection point H0 b,1 determine the rate of change of the heading angle of the front axle of the first trailer

[0091] Step 2. Determine the rate of change of the included angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer according to the rate of change of the heading angle of the tractor

[0092] According to equations (2) and (4), the rate of change of the included angle

[0093]

[0094] Step 3. Determine the steady-state speed of the center of the front axle of the first trailer when the front axle of the first trailer reaches the steady state of the rate of change of the speed v of the center of the front axle of the first trailer 1f and the rate of change of the heading angle of the front axle of the first trailer ​ and the steady-state heading angle change rate of the center of the front axle of the first trailer section

[0095] Among them, within the set monitoring time, if the change amount of the distance between the center of the front axle of the first trailer section and the center of the circle corresponding to the reference trajectory (i.e., the turning radius of the front axle) is less than the threshold value, it can be considered that the front axle of the first trailer section has reached a stable state.

[0096] It can be seen from the above formula (5) that if v0 and R0 are kept constant, then for any initial state it will gradually converge to a stable state The corresponding

[0097] When l b,1 ≠l h the expression of the stable state is:[[]]

[0098]

[0099] When l b,1 =l h the expression of the stable state is:[[]]

[0100]

[0101] Combining the above formulas (3), (4) and (6), (7), the steady-state speed and the steady-state heading angle change rate when the front axle of the first trailer section reaches the stable state can be obtained, that is

[0102]

[0103]

[0104] A more specific summary of the above process is: according to the change rate of the included angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer section, determine the steady-state change rate when the front axle of the first trailer section reaches the stable state. According to the steady-state change rate the speed v 1f of the center of the front axle of the first trailer section and the heading angle change rate of the front axle of the first trailer section, determine the steady-state speed of the center of the front axle of the first trailer section and the steady-state heading angle change rate

[0105] Step 4. If the reference distance R0 is less than the set threshold, according to the steady-state speed of the center of the front axle of the first trailer section and the steady-state heading angle change rate of the center of the front axle of the first trailer section determine the first turning radius of the front axle of the first trailer section at the first discrete point k

[0106] Let R thresh be the set threshold, which is used to judge whether the reference trajectory is a straight line. When the reference trajectory is a straight line, that is, R0≥R thresh it is considered that both the tractor and the trailer can travel along the reference trajectory more accurately. At this time, it is considered that the first turning radius of the front axle of the first trailer section at the first discrete point k is the turning radius of the rear axle of the tractor at the first discrete point k, that is, the reference distance R0 = R thresh , the difference between the reference distance and the first turning radius is 0, that is, the steady-state tracking deviation d 1f of the front axle of the first trailer section at this time is 0:

[0107]

[0108] When the reference trajectory is an arc-shaped trajectory with a certain curvature, that is, R0 < R thresh , according to the above formula (8), the first turning radius of the front axle of the first trailer section and the steady-state tracking deviation d 1f at the first discrete point k are respectively:

[0109]

[0110] Step 5. According to the first turning radius and the wheelbase l fr1 of the first trailer section, determine the steady-state included angle

[0111] between the heading of the front axle of the first trailer section and the heading of the rear axle of the first trailer section when the front axle of the first trailer section reaches a stable state Figure 9 Referring to the schematic diagram of the movement model of the rear axle turning of the first full-trailer section shown in

[0112]

[0113] When the center of the front axle of the first full-trailer section reaches a stable state, it can be obtained that:

[0114]

[0115] Step 6. According to the wheelbase l fr1 of the first trailer section and the steady-state included angle Determine the second turning radius of the rear axle of the first trailer section at the first discrete point k

[0116] From Equation (12), the turning radius when the center of the rear axle of the first trailer section reaches a steady state can be obtained and the steady-state tracking deviation d1:

[0117]

[0118] At this time, the speed at the center of the rear axle of the first trailer section (i.e., the steady-state speed) is:

[0119]

[0120] Generally, determining the first turning radius between the center of the front axle of each trailer section and the center of the reference trajectory, and the second turning radius between the center of the rear axle of each trailer section and the center of the reference trajectory according to the reference distance R0, the reference speed v0, the yaw rate of the tractor also includes:

[0121] According to the steady-state speed of the center of the front axle of the first trailer section when the front axle of the first trailer section reaches a steady state and the steady-state included angle determine the steady-state speed of the center of the rear axle of the first trailer section The steady-state speed of the center of the rear axle of the first trailer section is used to determine the fourth turning radius of the front axle of the second trailer section at the first discrete point k

[0122] Specifically, extend the above derivation process to the nth trailer section. When l b,n ≠l h,n-1 the expression of the steady state is:

[0123]

[0124] When l b,n =l h,n-1 the expression of the steady state is:

[0125]

[0126] When the speed and the yaw rate of the front axle of the nth trailer section reach a steady state, they are:

[0127]

[0128] According to Equation (17), the steady-state tracking deviation d of the front axle of the nth trailer section relative to the reference trajectory can be obtained when it reaches the steady state. nf . If R n-1 ≥R thresh When this is the case, the steady-state tracking deviation d of the front axle of the nth trailer section nf is 0:

[0129]

[0130] If R n-1 <R thresh , then the turning radius of the front axle of the nth trailer section and the steady-state tracking deviation d nf are respectively:

[0131]

[0132] When the center of the front axle of the nth full trailer reaches the steady state, it can be obtained that:

[0133]

[0134] From Equation (20), the turning radius and the steady-state tracking deviation d n of the center of the rear axle of the nth trailer section when it reaches the steady state can be obtained:

[0135]

[0136] At this time, the speed at the center of the rear axle of the nth trailer section is:

[0137]

[0138] It can be seen from Equation (9), Equation (10), Equation (13), Equation (18), Equation (19), and Equation (21) that the steady-state tracking deviation of each trailer relative to the reference trajectory is only related to the trailer size, as well as the reference radius and reference speed at discrete points on the reference trajectory. The evaluation of vehicle driving safety is realized without the need to determine the poses of each trailer section. This method is applicable to vehicles with trailers of different sizes and / or different numbers of trailers.

[0139] In summary, assuming that the tractor is towing 10 trailer sections, for the nth trailer section (n = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10), there are respectively the steady-state tracking deviation d nf of the front axle (i.e., the first deviation) and the steady-state tracking deviation d n of the rear axle (i.e., the second deviation). The steady-state tracking deviation d nf of the front axle and the steady-state tracking deviation d nThe larger value among them is determined as the steady - state tracking deviation of the n - th section of the trailer, or the steady - state tracking deviation d of the front axle nf and the steady - state tracking deviation d n of the rear axle are averaged to be determined as the steady - state tracking deviation of the n - th section of the trailer. The target tracking deviation is the maximum value among the n steady - state tracking deviations (i.e., the steady - state tracking deviations corresponding to each section of the trailer).

[0140] Generally speaking, determining the steady - state tracking deviation between the driving trajectories of each section of the trailer and the driving trajectory of the tractor based on the first turning radius, the second turning radius, and the reference distance includes:

[0141] Respectively determine the first deviation between the first turning radius and the reference distance, and the second deviation between the second turning radius and the reference distance; determine the larger value among the first deviation and the second deviation corresponding to the same trailer as the steady - state tracking deviation between the driving trajectory of the same trailer and the driving trajectory of the tractor.

[0142] The above gives the determination process of the first turning radius and the steady - state tracking deviation of the front axle of a full - trailer, and the second turning radius and the steady - state tracking deviation of the rear axle. For a semi - trailer, the determination method is similar to that of a full - trailer. The difference is that a semi - trailer has no front axle. Therefore, only the third turning radius and the steady - state tracking deviation of its rear axle need to be determined.

[0143] Specifically, for a semi - trailer, referring to the schematic diagram of the motion model of a tractor towing a semi - trailer moving along a curve as shown in Figure 10 、 Figure 11 and Figure 12 , where delta_f is the front - wheel steering angle of the tractor, v0 is the speed at the center of the rear axle of the tractor, and θ0 is the heading angle of the tractor.

[0144] For the first section of the semi - trailer, θ1 is the heading angle of the rear axle of the trailer. At this time, the included angle between the heading of the tractor and the heading of the rear axle of the first section of the trailer is v1 is the speed at the center of the rear axle of the first section of the trailer.

[0145] For the n - th section of the trailer, θ n is the heading angle of the rear axle of the trailer. At this time, the included angle between the heading of the (n - 1) - th section of the trailer and the heading of the rear axle of the n - th section of the trailer is vn is the speed at the center of the rear axle of the n - th section of the trailer.

[0146] Determine the reference radius at the reference trajectory point k as the reference distance R0 of the tractor at the reference trajectory point k, and determine the reference speed at the reference trajectory point k as the driving speed v0 of the tractor at the reference trajectory point k. That is, for any discrete reference trajectory point k, there is the following relational expression (23):

[0147] R0 = R r,k , v0 = v r,k (23)

[0148] At this time, the yaw rate of the tractor is as follows:

[0149]

[0150] On this basis, determining the third turning radius between the center of the rear axle of each trailer and the center of the reference trajectory circle when the tractor is towing each trailer along the reference trajectory includes the following steps:

[0151] (1) According to the reference speed v0, the yaw rate of the tractor the included angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer the distance l from the center of the rear axle of the tractor to the connection point H0 with the first trailer h and the distance l from the center of the rear axle of the first trailer to the connection point H0 fr1 determine the speed v1 of the center of the rear axle of the first trailer and the yaw rate of the rear axle of the first trailer

[0152] Refer to Figure 12 As shown, the speed v1 of the center of the rear axle of the first trailer can be determined by the following relational expression (25):

[0153]

[0154] The yaw rate of the rear axle of the first trailer can be determined by the following relational expression (26):

[0155]

[0156] (2) According to the yaw rate of the tractor and the yaw rate of the rear axle of the first trailer determine the change rate of the included angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer

[0157] According to Equation (24) and Equation (26), the change rate of can be obtained

[0158]

[0159] (3) According to the included angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer Rate of change Determine the steady-state angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer when the first trailer reaches a steady state

[0160] It can be seen from Equation (27) that if \(v_0\) and \(R_0\) are kept constant, then for any initial state It will gradually converge to a steady state The corresponding

[0161] When \(l\) fr1 ≠ \(l\) h , the steady state The expression is:

[0162]

[0163] When \(l\) fr1 = \(l\) h , the steady state The expression is:

[0164]

[0165] (4) According to the reference speed \(v_0\), the steady-state angle The rate of change of the heading angle of the tractor The distance \(l\) from the center of the rear axle of the tractor to the connection point \(H_0\) with the first trailer h And the distance \(l\) from the center of the rear axle of the first trailer to the connection point \(H_0\) fr1 Determine the steady-state speed of the first trailer when it reaches a steady state And the steady-state rate of change of the heading angle

[0166] (5) If the reference distance \(R_0\) is less than the set threshold, according to the steady-state speed And the steady-state rate of change of the heading angle Determine the third turning radius of the rear axle of the first trailer at the first discrete point \(k\)

[0167] Combining the above Equations (25), (26) and (28), (29), the steady-state speed when the first trailer reaches a steady state can be obtained And the steady-state rate of change of the heading angle

[0168]

[0169]

[0170] The steady-state tracking deviation of the first trailer section with respect to the reference trajectory when it reaches the steady state can be obtained according to Equation (30).

[0171] Let R thresh be the set threshold, which is used to determine whether the reference trajectory is a straight line. When the reference trajectory is a straight line, i.e., R0≥R thresh , it is considered that both the tractor and the trailer can travel along the reference trajectory relatively accurately. At this time, it is considered that at the first discrete point k, the third turning radius of the rear axle of the first trailer section is thresh equal to the turning radius of the rear axle of the tractor at the first discrete point k, i.e., the reference distance R0 = R

[0172]

[0173] The difference between the reference radius and the first turning radius is 0. That is, at this time, the steady-state tracking deviation d1 of the rear axle of the first trailer section is 0: thresh When the reference trajectory is a circular arc trajectory with a certain curvature, i.e., R0 < R , according to the above Equation (30), the third turning radius

[0174]

[0175] and the steady-state tracking deviation d1 of the rear axle of the first trailer section at the first discrete point k are respectively: frn ≠l h,h-1 When l , the expression of the stable state

[0176]

[0177] When l frn = l h,n-1 When l , the expression of the stable state

[0178]

[0179] When the steady-state speed and the steady-state heading angle change rate of the rear axle of the nth trailer section reach the steady state are:

[0180]

[0181] According to Equation (35), the steady-state tracking deviation of the nth trailer section with respect to the reference trajectory when it reaches the steady state can be obtained. If R n-1 ≥R thresh , the steady-state tracking deviation of the nth trailer section is 0:

[0182]

[0183] If R n-1 <R thresh , then the third turning radius and the steady-state tracking deviation of the nth trailer are respectively:

[0184]

[0185] Furthermore, considering that there may be curvature mutations in the reference trajectory, the reference radii at each discrete point on the reference trajectory may be different from each other, resulting in uneven corresponding data. Therefore, it is necessary to post-process the steady-state tracking deviation of the above-mentioned trailer to improve the smoothness of the data, and further improve the determination accuracy of vehicle driving safety.

[0186] Among them, the post-processing of the steady-state tracking deviation of each of the above-mentioned trailers can be performed using a sliding window filtering algorithm. Correspondingly, the vehicle driving safety determination method further includes:

[0187] Based on the sliding window filtering algorithm, perform filtering processing on the steady-state tracking deviation corresponding to each section of the trailer to obtain the filtered steady-state tracking deviation; correspondingly, the target tracking deviation is the maximum value in the filtered steady-state tracking deviation.

[0188] In the actual algorithm, in order to distinguish the left turn and right turn of the tractor along the reference trajectory, the reference radius and the steady-state tracking deviation can be set as signed variables. Along the forward direction of the tractor, if the reference trajectory is a counterclockwise arc, the reference radius and the steady-state tracking deviation are positive values, otherwise the reference radius and the steady-state tracking deviation are negative values. As Figure 13 shown.

[0189] Assume that K sampling points are obtained at equal intervals on the reference trajectory, and two arrays of size K are set, namely the left array Dl and the right array Dr, which respectively store the steady-state tracking deviations when turning left and right at each sampling point along the reference trajectory.

[0190] To sum up, for the kth sampling point (k = 1, 2,..., K) on the reference trajectory, there are steady-state tracking deviations of the front axle and rear axle of N trailers relative to this point, that is, d 1f , d1, d 2f , d2... d Nf , d N . Usually, the absolute value of the steady-state tracking deviation at the center of the rear axle of the last trailer is the largest. Therefore, the steady-state tracking deviation of the rear axle of the last trailer is used as the steady-state tracking deviation at the kth sampling point, that is, D k = d N . Then store D k into the left array Dl or the right array Dr. Specifically, if D k ≥ 0, then Dk Store it into the left array Dl, that is, Dl[k]=D k , Dr[k]=0; if D k <0, then store D k into the right array Dr, that is, Dl[k]=0, Dr[k]=|D k |.

[0191] Considering the steady-state tracking deviation of the trailer and the influence of the trailer size on the passability, conduct a collision safety assessment on the reference trajectory of the tractor towing multiple trailers. First, obtain the maximum values of the widths of N trailers and the width of the tractor body, that is:

[0192] Initial width w max =max(w0, w1, w2...w N ), where w0 represents the width of the tractor body, w1 represents the width of the first trailer, w2 represents the width of the second trailer, w N represents the width of the Nth trailer. That is, if the trailer width is greater than the tractor body width, expand the tractor body width to make it equal to the width of the widest trailer.

[0193] Then, superimpose the steady-state tracking deviation at the discrete points of the reference trajectory on the width of the tractor body after the above expansion, and superimpose an artificially set safety distance on the width of the tractor body to consider the influence of factors such as tracking error, positioning error, and trailer tracking deviation prediction error.

[0194] For any discrete point k of the reference trajectory, there is

[0195] W k,left =w max / 2+w s Dl[k]+D s

[0196] W k,right =w max / 2+w s Dr[k]+D s

[0197] In the formula, w s is the weight of the steady-state tracking deviation of the trailer, which can be given artificially or obtained according to the actual vehicle data, D s represents the safety distance, W k,left represents the width on the left side of the center of the tractor after expansion, W k,right represents the width on the right side of the center of the tractor after expansion. As Figure 14 shown in the schematic diagram of expanding the width of the tractor body.

[0198] Finally, perform collision detection using the vehicle body width after synthesizing the above three factors. If no collision occurs with obstacles near the reference trajectory, the reference trajectory is considered to meet the requirements for safe driving. Otherwise, the reference trajectory has a collision risk.

[0199] A vehicle driving safety determination method provided in this embodiment realizes the evaluation of vehicle driving safety without determining the poses of each trailer section, and this method is applicable to vehicles composed of trailers with different sizes and / or different numbers of trailers.

[0200] Figure 15 It is a schematic structural diagram of a vehicle driving safety determination device in an embodiment of the present disclosure. As Figure 15 shown: The device includes: a first determination module 1510, a second determination module 1520, and a third determination module 1530.

[0201] The first determination module 1510 is configured to determine the maximum value among the body width of the tractor and the widths of each trailer section towed by the tractor as the initial width; the second determination module 1520 is configured to process the body width of the tractor based on a reference dimension and / or the initial width to obtain the target width of the tractor, where the target width is greater than the initial width, and the reference dimension includes at least one of a preset safety distance and a target tracking deviation, and the target tracking deviation is the maximum value of the steady-state tracking deviation between the driving trajectories of each trailer section and the driving trajectory of the tractor when the tractor travels along the reference trajectory; the third determination module 1530 is configured to determine whether the tractor can tow each trailer section to drive safely along the reference trajectory according to the target width.

[0202] Optionally, it further includes: a fourth determination module, configured to, when each trailer section is a full-trailer, determine a first turning radius between the front axle center of each trailer section and the center of the circle of the reference trajectory, and a second turning radius between the rear axle center of each trailer section and the center of the circle of the reference trajectory based on the kinematic model when the tractor tows each trailer section to travel along the reference trajectory; determine the steady-state tracking deviation between the driving trajectories of each trailer section and the driving trajectory of the tractor based on the first turning radius, the second turning radius, and a reference distance; when each trailer section is a semi-trailer, determine a third turning radius between the rear axle center of each trailer section and the center of the circle of the reference trajectory based on the kinematic model when the tractor tows each trailer section to travel along the reference trajectory; determine the steady-state tracking deviation between the driving trajectories of each trailer section and the driving trajectory of the tractor based on the third turning radius and the reference distance.

[0203] Optionally, it further includes: a fifth determination module, configured to determine the speed at the first discrete point on the reference trajectory as the reference speed of the center of the rear axle of the tractor, and determine the reference radius corresponding to the first discrete point as the reference distance between the center of the rear axle of the tractor and the center of the circle corresponding to the first discrete point, where the reference trajectory is composed of multiple discrete points, and the first discrete point is one of the multiple discrete points; determine the yaw rate of change of the tractor according to the reference speed and the reference distance.

[0204] Optionally, the fourth determination module includes:

[0205] a first determination unit, configured to determine the speed of the center of the front axle of the first trailer and the yaw rate of change of the front axle of the first trailer according to the reference speed, the yaw rate of change of the tractor, the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer, the distance from the center of the rear axle of the tractor to the connection point with the first trailer, and the distance from the center of the front axle of the first trailer to the connection point;

[0206] a second determination unit, configured to determine the rate of change of the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer according to the yaw rate of change of the tractor and the yaw rate of change of the front axle of the first trailer;

[0207] a third determination unit, configured to determine the steady-state speed of the center of the front axle of the first trailer and the steady-state yaw rate of change of the center of the front axle of the first trailer when the front axle of the first trailer reaches a steady state according to the rate of change of the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer, the speed of the center of the front axle of the first trailer, and the yaw rate of change of the front axle of the first trailer;

[0208] a fourth determination unit, configured to determine the first turning radius at the first discrete point according to the steady-state speed of the center of the front axle of the first trailer and the steady-state yaw rate of change of the center of the front axle of the first trailer if the reference distance is less than a set threshold;

[0209] a fifth determination unit, configured to determine the steady-state angle between the heading of the front axle of the first trailer and the heading of the rear axle of the first trailer when the front axle of the first trailer reaches a steady state according to the first turning radius and the wheelbase of the first trailer;

[0210] a sixth determination unit, configured to determine the second turning radius at the first discrete point according to the wheelbase of the first trailer and the steady-state angle; where the distance from the center of the rear axle of the tractor to the connection point with the first trailer, the distance from the center of the front axle of the first trailer to the connection point, and the wheelbase of the first trailer are determined based on the kinematic model when the tractor is towing each trailer along the reference trajectory.

[0211] Optionally, the first determining unit is specifically configured to: determine the speed of the center of the front axle of the first trailer according to the reference speed, the yaw rate of the tractor, the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer, and the distance from the center of the rear axle of the tractor to the connection point with the first trailer; determine the yaw rate of the center of the front axle of the first trailer according to the reference speed, the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer, the yaw rate of the tractor, the distance from the center of the rear axle of the tractor to the connection point with the first trailer, and the distance from the center of the front axle of the first trailer to the connection point. The third determining unit is specifically configured to: determine the steady-state change rate when the front axle of the first trailer reaches a steady state according to the change rate of the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer; determine the steady-state speed of the center of the front axle of the first trailer and the steady-state yaw rate of the center of the front axle of the first trailer according to the steady-state change rate, the speed of the center of the front axle of the first trailer, and the yaw rate of the center of the front axle of the first trailer.

[0212] Optionally, the fourth determining module further includes: a seventh determining unit, configured to determine the steady-state speed of the center of the rear axle of the first trailer according to the steady-state speed of the center of the front axle of the first trailer when the front axle of the first trailer reaches a steady state and the steady-state angle, where the steady-state speed of the center of the rear axle of the first trailer is used to determine the fourth turning radius from the center of the front axle of the second trailer to the center of the circle corresponding to the first discrete point k.

[0213] Optionally, the fourth determining module further includes: an eighth determining unit, configured to determine the speed of the center of the rear axle of the first trailer and the yaw rate of the center of the rear axle of the first trailer according to the reference speed, the yaw rate of the tractor, the angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer, the distance from the center of the rear axle of the tractor to the connection point with the first trailer, and the distance from the center of the rear axle of the first trailer to the connection point; determine the change rate of the angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer according to the yaw rate of the tractor and the yaw rate of the center of the rear axle of the first trailer; determine the steady-state angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer when the first trailer reaches a steady state according to the change rate of the angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer; determine the steady-state speed and the steady-state yaw rate when the first trailer reaches a steady state according to the reference speed, the steady-state angle, the yaw rate of the tractor, the distance from the center of the rear axle of the tractor to the connection point with the first trailer, and the distance from the center of the rear axle of the first trailer to the connection point; if the reference distance is less than the set threshold, determine the third turning radius at the first discrete point according to the steady-state speed and the steady-state yaw rate.

[0214] Optionally, the fourth determination module further includes: a ninth determination unit configured to respectively determine a first deviation between the first turning radius and a reference distance, and a second deviation between the second turning radius and the reference distance; and determine the larger value among the first deviation and the second deviation corresponding to the same trailer as the steady-state tracking deviation between the driving trajectory of the same trailer and the driving trajectory of the tractor.

[0215] Optionally, it further includes a filtering module configured to perform filtering processing on the steady-state tracking deviations corresponding to each trailer based on a sliding window filtering algorithm to obtain the filtered steady-state tracking deviations; correspondingly, the target tracking deviation is the maximum value among the filtered steady-state tracking deviations.

[0216] Optionally, if the reference dimension includes a preset safety distance and a target tracking deviation, and the reference trajectory is a clockwise circular arc trajectory with a set curvature, the second determination module is specifically configured to: use the center of the vehicle body width of the tractor as a reference point, and expand the same width on both sides of the reference point transversely to obtain a first width of the expanded tractor, where the first width is the sum of the initial width and the preset safety distance; and continue to expand the first width in the direction close to the center of the reference trajectory to obtain a second width of the expanded tractor, where the second width is the sum of the initial width, the preset safety distance, and the target tracking deviation.

[0217] The vehicle driving safety determination device provided in the embodiments of the present disclosure can execute the steps in the vehicle driving safety determination method provided in the method embodiments of the present disclosure, and the implementation steps and beneficial effects are not described herein again.

[0218] Figure 16 It is a schematic structural diagram of an electronic device in the embodiments of the present disclosure. Specifically refer to Figure 16 below, which shows a schematic structural diagram of an electronic device 500 suitable for implementing the embodiments of the present disclosure. Figure 16 The electronic device shown is only an example and should not impose any limitation on the functions and usage scope of the embodiments of the present disclosure.

[0219] Such as Figure 16As shown, the electronic device 500 may include a processing device (such as a central processing unit, a graphics processing unit, etc.) 501, which may perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 502 or the program loaded from the storage device 508 into the random access memory (RAM) 503 to implement the method of the embodiments as described in the present disclosure. In the RAM 503, various programs and data required for the operation of the electronic device 500 are also stored. The processing device 501, the ROM 502, and the RAM 503 are connected to each other through a bus 504. The input / output (I / O) interface 505 is also connected to the bus 504.

[0220] Specifically, according to an embodiment of the present disclosure, the process described above with reference to the flowchart may be implemented as a computer software program. For example, an embodiment of the present disclosure includes a computer program product, which includes a computer program carried on a non-transitory computer-readable medium, and the computer program includes program codes for executing the method shown in the flowchart, so as to implement the vehicle driving safety determination method as described above. In such an embodiment, the computer program may be downloaded and installed from the network through the communication device 509, or installed from the storage device 508, or installed from the ROM 502. When the computer program is executed by the processing device 501, the above functions defined in the method of the embodiment of the present disclosure are executed.

[0221] Solution 1. A vehicle driving safety determination method, the method comprising:

[0222] Determine the maximum value of the body width of the tractor and the widths of each trailer towed by the tractor as the initial width;

[0223] Process the body width of the tractor based on a reference dimension and / or the initial width to obtain a target width of the tractor, wherein the target width is greater than the initial width, and the reference dimension includes at least one of a preset safety distance and a target tracking deviation, and the target tracking deviation is the maximum value of the steady-state tracking deviation between the driving trajectories of each trailer and the driving trajectory of the tractor when the tractor travels along a reference trajectory;

[0224] Determine whether the tractor towing each trailer can safely travel along the reference trajectory according to the target width.

[0225] Solution 2. According to the method of Solution 1, when each trailer is a full trailer, based on the kinematic model when the tractor tows each trailer along the reference trajectory, determine the first turning radius between the center of the front axle of each trailer and the center of the circle of the reference trajectory, and the second turning radius between the center of the rear axle of each trailer and the center of the circle of the reference trajectory; based on the first turning radius, the second turning radius and the reference distance, determine the steady-state tracking deviation between the driving trajectory of each trailer and the driving trajectory of the tractor.

[0226] When each trailer is a semi-trailer, based on the kinematic model when the tractor tows each trailer along the reference trajectory, determine the third turning radius between the center of the rear axle of each trailer and the center of the circle of the reference trajectory; based on the third turning radius and the reference distance, determine the steady-state tracking deviation between the driving trajectory of each trailer and the driving trajectory of the tractor.

[0227] Solution 3. According to the method of Solution 2, determine the reference speed at the first discrete point on the reference trajectory as the reference speed of the center of the rear axle of the tractor, and determine the reference radius corresponding to the first discrete point as the reference distance between the center of the rear axle of the tractor and the center of the circle corresponding to the first discrete point. The reference trajectory consists of multiple discrete points, and the first discrete point is one of the multiple discrete points;

[0228] Determine the yaw rate change of the tractor according to the reference speed and the reference distance.

[0229] Solution 4. According to the method of Solution 3, the step of determining the first turning radius between the center of the front axle of each trailer and the center of the circle of the reference trajectory, and the second turning radius between the center of the rear axle of each trailer and the center of the circle of the reference trajectory based on the kinematic model when the tractor tows each trailer along the reference trajectory includes:

[0230] Determine the speed of the center of the front axle of the first trailer and the yaw rate change of the front axle of the first trailer according to the reference speed, the yaw rate change of the tractor, the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer, the distance from the center of the rear axle of the tractor to the connection point with the first trailer, and the distance from the center of the front axle of the first trailer to the connection point;

[0231] Determine the change rate of the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer according to the yaw rate change of the tractor and the yaw rate change of the front axle of the first trailer;

[0232] Determine the steady-state speed of the center of the front axle of the first trailer section and the steady-state yaw rate of the center of the front axle of the first trailer section when the front axle of the first trailer section reaches a steady state based on the rate of change of the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer section, the speed of the center of the front axle of the first trailer section, and the yaw rate of the front axle of the first trailer section;

[0233] If the reference distance is less than the set threshold, determine the first turning radius at the first discrete point based on the steady-state speed of the center of the front axle of the first trailer section and the steady-state yaw rate of the center of the front axle of the first trailer section;

[0234] Determine the steady-state angle between the heading of the front axle of the first trailer section and the heading of the rear axle of the first trailer section when the front axle of the first trailer section reaches a steady state based on the first turning radius and the wheelbase of the first trailer section;

[0235] Determine the second turning radius at the first discrete point based on the wheelbase of the first trailer section and the steady-state angle;

[0236] Wherein, the distance from the center of the rear axle of the tractor to the connection point with the first trailer section, the distance from the center of the front axle of the first trailer section to the connection point, and the wheelbase of the first trailer section are determined based on the kinematic model when the tractor towes each trailer section along the reference trajectory.

[0237] Solution 5. According to the method described in Solution 4, the determining of the speed of the center of the front axle of the first trailer section and the yaw rate of the front axle of the first trailer section based on the reference speed, the yaw rate of the tractor, the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer section, the distance from the center of the rear axle of the tractor to the connection point with the first trailer section, and the distance from the center of the front axle of the first trailer section to the connection point includes:

[0238] Determine the speed of the center of the front axle of the first trailer section based on the reference speed, the yaw rate of the tractor, the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer section, and the distance from the center of the rear axle of the tractor to the connection point with the first trailer section;

[0239] Determine the yaw rate of the front axle of the first trailer section based on the reference speed, the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer section, the yaw rate of the tractor, the distance from the center of the rear axle of the tractor to the connection point with the first trailer section, and the distance from the center of the front axle of the first trailer section to the connection point;

[0240] Determining the steady-state speed of the center of the front axle of the first trailer section and the steady-state yaw rate of the center of the front axle of the first trailer section when the front axle of the first trailer section reaches a steady state according to the rate of change of the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer section, the speed of the center of the front axle of the first trailer section, and the rate of change of the heading angle of the front axle of the first trailer section, includes:

[0241] Determining the steady-state rate of change when the front axle of the first trailer section reaches a steady state according to the rate of change of the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer section;

[0242] Determining the steady-state speed of the center of the front axle of the first trailer section and the steady-state yaw rate of the center of the front axle of the first trailer section according to the steady-state rate of change, the speed of the center of the front axle of the first trailer section, and the rate of change of the heading angle of the front axle of the first trailer section.

[0243] Solution 6. According to the method described in Solution 4, the method for determining the first turning radius between the center of the front axle of each trailer section and the center of the reference trajectory circle, and the second turning radius between the center of the rear axle of each trailer section and the center of the reference trajectory circle according to the reference distance, the reference speed, the rate of change of the heading angle of the tractor, and the kinematic model, further includes:

[0244] Determining the steady-state speed of the center of the rear axle of the first trailer section according to the steady-state speed of the center of the front axle of the first trailer section when the front axle of the first trailer section reaches a steady state and the steady-state angle, and the steady-state speed of the center of the rear axle of the first trailer section is used to determine the fourth turning radius from the center of the front axle of the second trailer section to the center of the circle corresponding to the first discrete point k.

[0245] Solution 7. According to the method described in Solution 3, the method for determining the third turning radius between the center of the rear axle of each trailer section and the center of the reference trajectory circle based on the kinematic model when the tractor is towing each trailer section along the reference trajectory, includes:

[0246] Determining the speed of the center of the rear axle of the first trailer section and the rate of change of the heading angle of the rear axle of the first trailer section according to the reference speed, the rate of change of the heading angle of the tractor, the angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer section, the distance from the center of the rear axle of the tractor to the connection point with the first trailer section, and the distance from the center of the rear axle of the first trailer section to the connection point;

[0247] Determining the rate of change of the angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer section according to the rate of change of the heading angle of the tractor and the rate of change of the heading angle of the rear axle of the first trailer section;

[0248] Determine the steady-state angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer when the first trailer reaches a steady state according to the change rate of the angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer;

[0249] Determine the steady-state speed and the steady-state heading angle change rate of the first trailer when it reaches a steady state according to the reference speed, the steady-state angle, the change rate of the heading angle of the tractor, the distance from the center of the rear axle of the tractor to the connection point with the first trailer, and the distance from the center of the rear axle of the first trailer to the connection point;

[0250] If the reference distance is less than the set threshold, determine the third turning radius at the first discrete point according to the steady-state speed and the steady-state heading angle change rate.

[0251] Solution 8. According to the method described in Solution 3, the method for determining the steady-state tracking deviation between the driving trajectories of each trailer and the driving trajectory of the tractor based on the first turning radius, the second turning radius, and the reference distance includes:

[0252] Respectively determine the first deviation between the first turning radius and the reference distance, and the second deviation between the second turning radius and the reference distance;

[0253] Determine the larger value among the first deviation and the second deviation corresponding to the same trailer as the steady-state tracking deviation between the driving trajectory of the same trailer and the driving trajectory of the tractor.

[0254] Solution 9. According to the method described in Solution 1, the method further includes: performing filtering processing on the steady-state tracking deviation corresponding to each trailer based on a sliding window filtering algorithm to obtain the filtered steady-state tracking deviation;

[0255] Correspondingly, the target tracking deviation is the maximum value in the filtered steady-state tracking deviation.

[0256] Solution 10. According to the method described in any one of Solutions 1-8, if the reference dimension includes a preset safety distance and a target tracking deviation, and the reference trajectory is a circular arc trajectory with a set curvature and in a clockwise direction, process the body width of the tractor based on the reference dimension and the initial width to obtain the target width of the tractor, including:

[0257] Taking the center of the body width of the tractor as a reference point, expand the same width on both sides of the reference point in the horizontal direction to obtain the first width of the expanded tractor, and the first width is the sum of the initial width and the preset safety distance;

[0258] Expand the first width in the direction of the center of the reference trajectory to obtain the second width of the tractor after expansion, where the second width is the sum of the initial width, the preset safety distance, and the target tracking deviation.

[0259] Solution 11. A vehicle driving safety determination device includes: a first determination module for determining the maximum value among the body width of the tractor and the widths of each trailer towed by the tractor as the initial width;

[0260] A second determination module for processing the body width of the tractor based on a reference dimension and / or the initial width to obtain the target width of the tractor, where the target width is greater than the initial width, the reference dimension includes at least one of a preset safety distance and a target tracking deviation, and the target tracking deviation is the maximum value among the steady-state tracking deviations between the driving trajectories of each trailer and the driving trajectory of the tractor when the tractor travels along the reference trajectory;

[0261] A third determination module for determining whether the tractor towing each trailer can safely travel along the reference trajectory according to the target width.

[0262] Solution 12. An electronic device, the electronic device includes:

[0263] One or more processors;

[0264] A storage device for storing one or more programs;

[0265] When the one or more programs are executed by the one or more processors, the one or more processors implement the method according to any one of Solutions 1-10.

[0266] Solution 13. A computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, it implements the method according to any one of Solutions 1-10.

[0267] The above description is only a preferred embodiment of the present disclosure and an explanation of the applied technical principles. Those skilled in the art should understand that the scope of disclosure involved in the present disclosure is not limited to the technical solutions formed by the specific combination of the above technical features, and should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above disclosure concept. For example, the technical solutions formed by mutually replacing the above features with the (but not limited to) technical features having similar functions disclosed in the present disclosure.

Claims

1. A method for determining vehicle driving safety, characterized in that, The method includes: Determining the maximum value among the body width of the tractor and the widths of the trailers towed by the tractor as the initial width; Processing the body width of the tractor based on a reference dimension and / or the initial width to obtain the target width of the tractor, where the target width is greater than the initial width, and the reference dimension includes at least one of a preset safety distance and a target tracking deviation, and the target tracking deviation is the maximum value among the steady-state tracking deviations between the travel trajectories of the trailers and the travel trajectory of the tractor when the tractor travels along a reference trajectory; Determining whether the tractor towing the trailers can safely travel along the reference trajectory according to the target width; The method further includes: performing filtering processing on the steady-state tracking deviations respectively corresponding to the trailers based on a sliding window filtering algorithm to obtain the filtered steady-state tracking deviations; Correspondingly, the target tracking deviation is the maximum value among the filtered steady-state tracking deviations.

2. The method according to claim 1, characterized in that The method further includes: When the trailers are full trailers, determining a first turning radius between the front axle center of each trailer and the center of the circle of the reference trajectory, and a second turning radius between the rear axle center of each trailer and the center of the circle of the reference trajectory based on the kinematic model when the tractor tows the trailers and travels along the reference trajectory; determining the steady-state tracking deviation between the travel trajectories of the trailers and the travel trajectory of the tractor based on the first turning radius, the second turning radius, and a reference distance, where the reference distance is determined based on the reference trajectory; When the trailers are semi-trailers, determining a third turning radius between the rear axle center of each trailer and the center of the circle of the reference trajectory based on the kinematic model when the tractor tows the trailers and travels along the reference trajectory; determining the steady-state tracking deviation between the travel trajectories of the trailers and the travel trajectory of the tractor based on the third turning radius and the reference distance.

3. The method according to claim 2, wherein It further includes: Determining the speed at a first discrete point on the reference trajectory as the reference speed of the rear axle center of the tractor, and determining the reference radius corresponding to the first discrete point as the reference distance between the rear axle center of the tractor and the center of the circle corresponding to the first discrete point, where the reference trajectory is composed of multiple discrete points, and the first discrete point is one of the multiple discrete points; Determining the yaw rate change of the tractor according to the reference speed and the reference distance.

4. The method according to claim 3, wherein The determining a first turning radius between the front axle center of each trailer and the center of the circle of the reference trajectory, and a second turning radius between the rear axle center of each trailer and the center of the circle of the reference trajectory based on the kinematic model when the tractor tows the trailers and travels along the reference trajectory includes: Determining the speed of the front axle center of the first trailer and the yaw rate change of the front axle of the first trailer according to the reference speed, the yaw rate change of the tractor, the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer, the distance from the rear axle center of the tractor to the connection point with the first trailer, and the distance from the front axle center of the first trailer to the connection point; Determine the rate of change of the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer according to the rate of change of the heading angle of the tractor and the rate of change of the heading angle of the front axle of the first trailer; Determine the steady-state speed of the center of the front axle of the first trailer and the steady-state rate of change of the heading angle of the center of the front axle of the first trailer when the front axle of the first trailer reaches a steady state according to the rate of change of the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer, the speed of the center of the front axle of the first trailer, and the rate of change of the heading angle of the front axle of the first trailer; If the reference distance is less than the set threshold, determine the first turning radius at the first discrete point according to the steady-state speed of the center of the front axle of the first trailer and the steady-state rate of change of the heading angle of the center of the front axle of the first trailer; Determine the steady-state angle between the heading of the front axle of the first trailer and the heading of the rear axle of the first trailer when the front axle of the first trailer reaches a steady state according to the first turning radius and the wheelbase of the first trailer; Determine the second turning radius at the first discrete point according to the wheelbase of the first trailer and the steady-state angle; Wherein, the distance from the center of the rear axle of the tractor to the connection point with the first trailer, the distance from the center of the front axle of the first trailer to the connection point, and the wheelbase of the first trailer are determined based on the kinematic model when the tractor tows each trailer along the reference trajectory.

5. The method according to claim 4, characterized in that, The determining the speed of the center of the front axle of the first trailer and the rate of change of the heading angle of the front axle of the first trailer according to the reference speed, the rate of change of the heading angle of the tractor, the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer, the distance from the center of the rear axle of the tractor to the connection point with the first trailer, and the distance from the center of the front axle of the first trailer to the connection point includes: Determine the speed of the center of the front axle of the first trailer according to the reference speed, the rate of change of the heading angle of the tractor, the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer, and the distance from the center of the rear axle of the tractor to the connection point with the first trailer; Determine the rate of change of the heading angle of the front axle of the first trailer according to the reference speed, the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer, the rate of change of the heading angle of the tractor, the distance from the center of the rear axle of the tractor to the connection point with the first trailer, and the distance from the center of the front axle of the first trailer to the connection point; The determining the steady-state speed of the center of the front axle of the first trailer and the steady-state rate of change of the heading angle of the center of the front axle of the first trailer when the front axle of the first trailer reaches a steady state according to the rate of change of the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer, the speed of the center of the front axle of the first trailer, and the rate of change of the heading angle of the front axle of the first trailer includes: Determine the steady-state rate of change when the front axle of the first trailer reaches a steady state according to the rate of change of the angle between the heading of the rear axle of the tractor and the heading of the front axle of the first trailer; Determine the steady-state speed of the center of the front axle of the first trailer and the steady-state rate of change of the heading angle of the center of the front axle of the first trailer according to the steady-state rate of change, the speed of the center of the front axle of the first trailer, and the rate of change of the heading angle of the front axle of the first trailer.

6. The method according to claim 4, characterized in that, Further included are: Determining the steady-state speed of the center of the front axle of the first trailer section when the front axle of the first trailer section reaches a steady state and the steady-state angle, and the steady-state speed of the center of the rear axle of the first trailer section is used to determine the fourth turning radius from the center of the front axle of the second trailer section to the center of the circle corresponding to the first discrete point.

7. The method according to claim 3, characterized in that The determining the third turning radius between the center of the rear axle of each trailer section and the center of the circle of the reference trajectory based on the kinematic model when the tractor is towing each trailer section along the reference trajectory includes: Determining the speed of the center of the rear axle of the first trailer section and the rate of change of the heading angle of the rear axle of the first trailer section according to the reference speed, the rate of change of the heading angle of the tractor, the angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer section, the distance from the center of the rear axle of the tractor to the connection point with the first trailer section, and the distance from the center of the rear axle of the first trailer section to the connection point; Determining the rate of change of the angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer section according to the rate of change of the heading angle of the tractor and the rate of change of the heading angle of the rear axle of the first trailer section; Determining the steady-state angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer section when the first trailer section reaches a steady state according to the rate of change of the angle between the heading of the rear axle of the tractor and the heading of the rear axle of the first trailer section; Determining the steady-state speed and the steady-state rate of change of the heading angle when the first trailer section reaches a steady state according to the reference speed, the steady-state angle, the rate of change of the heading angle of the tractor, the distance from the center of the rear axle of the tractor to the connection point with the first trailer section, and the distance from the center of the rear axle of the first trailer section to the connection point; If the reference distance is less than the set threshold, determining the third turning radius at the first discrete point according to the steady-state speed and the steady-state rate of change of the heading angle.

8. The method according to claim 3, characterized in that, The determining the steady-state tracking deviation between the driving trajectories of each trailer section and the driving trajectory of the tractor based on the first turning radius, the second turning radius, and the reference distance includes: Respectively determining a first deviation between the first turning radius and the reference distance, and a second deviation between the second turning radius and the reference distance; Determining the larger value among the first deviation and the second deviation corresponding to the same trailer section as the steady-state tracking deviation between the driving trajectory of the same trailer section and the driving trajectory of the tractor.

9. The method according to any one of claims 1-8, characterized in that, If the reference dimension includes a preset safety distance and a target tracking deviation, and the reference trajectory is a clockwise circular arc trajectory with a set curvature, processing the body width of the tractor based on the reference dimension and the initial width to obtain the target width of the tractor, including: Taking the center of the body width of the tractor as a reference point, respectively expanding the same width on both sides of the reference point transversely to obtain the first width of the expanded tractor, and the first width is the sum of the initial width and the preset safety distance; Expand the first width in the direction of the center of the reference trajectory to obtain the second width of the tractor after expansion, where the second width is the sum of the initial width, the preset safety distance, and the target tracking deviation.

10. A vehicle driving safety determination device, characterized in that, Comprising: A first determination module, configured to determine the maximum value among the body width of the tractor and the widths of the trailers towed by the tractor as the initial width; A second determination module, configured to process the body width of the tractor based on a reference dimension and / or the initial width to obtain the target width of the tractor, where the target width is greater than the initial width, and the reference dimension includes at least one of a preset safety distance and a target tracking deviation, and the target tracking deviation is the maximum value among the steady-state tracking deviations between the travel trajectories of the trailers and the travel trajectory of the tractor when the tractor travels along the reference trajectory; A third determination module, configured to determine whether the tractor towing the trailers can travel safely along the reference trajectory according to the target width; The vehicle travel safety determination device further includes a filtering module, configured to perform filtering processing on the steady-state tracking deviations respectively corresponding to the trailers based on a sliding window filtering algorithm to obtain the filtered steady-state tracking deviations; correspondingly, the target tracking deviation is the maximum value among the filtered steady-state tracking deviations.

11. An electronic device, characterized in that, The electronic device includes: One or more processors; A storage device, configured to store one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the method according to any one of claims 1-9.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method according to any one of claims 1-9.

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