Method for dynamically adjusting straight steering angle of automatic driving vehicle

Abstract

The invention relates to the technical field of vehicle automatic driving, and provides a method for dynamically adjusting a straight steering angle of an automatic driving vehicle, which comprises the following steps of: determining a driving route and a plurality of target path points corresponding to the driving route, determining a current coordinate point of the vehicle, and calculating distances from the current coordinate point to all the target path points; determining a reference point and a reference course and a reference curvature of the vehicle; calculating transverse deviation and course deviation of the vehicle; judging whether the speed, the lateral deviation, the course deviation and the reference curvature of the current vehicle meet set conditions or not, if the set conditions are met, recording the numerical value and the quantity of the lateral deviation, and after the quantity meets an accumulated lateral deviation quantity threshold value of the vehicle, calculating an average lateral deviation according to the recorded lateral deviation data and quantity; the average transverse deviation is not smaller than the transverse deviation threshold value, the straight steering angle is adjusted according to the average transverse deviation, and the path following precision under the working conditions of different load distribution, different road roll angles, uneven tire pressure and the like is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle automatic driving, and in particular to a method for dynamically adjusting the straight-ahead steering angle of an automatic driving vehicle. Background Art

[0002] In recent years, autonomous driving technology has developed rapidly. Assisted driving technologies such as cruise control, adaptive cruise control, and lane keeping have gradually entered people's daily traffic life, with huge development potential and broad application prospects. Lateral control technology is one of the key technologies in the field of unmanned driving. It changes the vehicle's heading and yaw rate by controlling the steering system, while ensuring comfort, safety, and following accuracy. Following accuracy is an important indicator for measuring lateral control technology.

[0003] Current research focuses on vehicle dynamics modeling, optimization of solution algorithms, and other aspects, with an emphasis on solving upper-level control algorithm problems. However, as the actuator of the upper-level control algorithm, the steering system's accurate measurement of the straight-line steering angle directly affects the following accuracy of the autonomous vehicle under high-speed conditions. The current method for determining the straight-line steering angle of an autonomous vehicle mainly uses a comprehensive judgment of yaw rate sensors, wheel angle sensors, and expected wheel angles. A large number of sensors are used, and the cost is high. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the related art. To this end, the present invention provides a method for dynamically adjusting the steering angle of an autonomous driving vehicle in a straight line, so as to improve the path following accuracy under different load distribution, different road roll angles, uneven tire pressure and other working conditions.

[0005] The present invention provides a method for dynamically adjusting the steering angle of an automatic driving vehicle, comprising the following steps: S1: Determine the driving route and multiple target path points corresponding to the driving route P j ,in, P j For the j target waypoints, j The value is an integer greater than or equal to 1; S2: Determine the current coordinate point of the vehicle Q , calculate the current coordinate point Q and each target path point P j The distance between l j ; S3: Identify the current coordinate point Q and each target path point P j The distance between lj The minimum value in l i And determine the target path point corresponding to the minimum value P j As a reference point P i , the driving heading corresponding to the reference point is used as the reference heading of the vehicle, and the curvature of the driving route corresponding to the reference point is used as the current coordinate point on the driving route of the vehicle Q The reference curvature at ; S4: Calculate the lateral deviation and heading deviation of the vehicle according to the coordinates and heading of the vehicle and the reference point; S5: obtaining the current speed of the vehicle, determining whether the current speed of the vehicle, the lateral deviation, the heading deviation and the reference curvature meet the set conditions, and returning to step S2 if the set conditions are not met; S6: if the set conditions are met, the lateral deviation value of the vehicle and the cumulative lateral deviation amount of the vehicle are recorded, and it is determined whether the cumulative lateral deviation amount reaches the cumulative lateral deviation amount threshold of the vehicle, and if not, the process returns to step S2; S7: after reaching the cumulative lateral deviation threshold of the vehicle, calculating the average lateral deviation according to the recorded lateral deviation value of the vehicle and the cumulative lateral deviation of the vehicle, when the absolute value of the average lateral deviation is less than the lateral deviation threshold, returning to step S2; S8: When the absolute value of the average lateral deviation is not less than the lateral deviation threshold, the straight-ahead steering angle of the vehicle is adjusted according to the average lateral deviation. After the adjustment is completed, the vehicle starts to travel.

[0006] According to a method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention, S2 comprises the following steps: Calculate the current coordinate point Q and each target path point P j The distance between l j , the formula is as follows: in, The current coordinate point of the vehicle Q Arrive at j The distance to the target path point, Indicates the current coordinate point of the vehicle Q The horizontal axis of Indicates the current coordinate point of the vehicle Q The vertical coordinate of Indicates the target path point P j The horizontal axis of Indicates the target path pointP j The vertical coordinate of .

[0007] According to a method for dynamically adjusting the steering angle of an autonomous driving vehicle in a straight line provided by the present invention, the current coordinate point is identified. Q and each target path point P j The distance between l j The minimum value in l i Use the following formula: in, The current coordinate point of the vehicle Q The distance to the last target waypoint, As reference point P i The sequence number of the corresponding target path point, The value is an integer greater than or equal to 1.

[0008] According to a method for dynamically adjusting the steering angle of an autonomous driving vehicle traveling straight ahead provided by the present invention, the lateral deviation is calculated using the following formula: in, Indicates the lateral deviation of the vehicle, Indicates the current coordinate point of the vehicle Q The vertical coordinate of y i Indicates reference point P i The vertical coordinate of Indicates reference point P i The heading angle, X Indicates the current coordinate point of the vehicle Q The horizontal axis of x i Indicates reference point P i The horizontal axis of .

[0009] According to a method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention, the heading deviation is calculated using the following formula: in, Indicates the vehicle's heading deviation, Indicates the current heading angle of the vehicle. Indicates reference point P i The heading angle.

[0010] According to a method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention, S5 comprises the following steps: Determine a vehicle speed threshold lower limit, a lateral deviation threshold lower limit, a heading deviation threshold upper limit, and a reference curvature threshold upper limit, and set conditions to simultaneously satisfy the following conditions: the current speed of the vehicle is not less than the vehicle speed threshold lower limit, the lateral deviation is not less than the lateral deviation threshold lower limit, the heading deviation is not greater than the heading deviation threshold upper limit, and the reference curvature is not greater than the reference curvature threshold upper limit.

[0011] According to a method for dynamically adjusting the steering angle of an autonomous driving vehicle traveling straight ahead provided by the present invention, the average lateral deviation is calculated using the following formula: in, is the average lateral deviation, For the record r The lateral deviation value, r To record the cumulative lateral deviation of the vehicle, is the cumulative lateral deviation threshold of the vehicle.

[0012] According to a method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention, adjusting the straight-ahead steering angle of the vehicle comprises the following steps: The basic adjustment value is set. If the average lateral deviation is a positive value, the basic adjustment value is added to the straight-ahead steering angle. If the average lateral deviation is a negative value, the basic adjustment value is subtracted from the straight-ahead steering angle.

[0013] According to a method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention, the basic adjustment value ranges from 0.01% to 0.05% of the straight-ahead steering angle.

[0014] According to a method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention, S7 includes the following steps: after calculating the average lateral deviation, deleting the recorded lateral deviation data, and recording the current lateral deviation data.

[0015] The above one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects: According to the method for dynamically adjusting the straight-line steering angle of an autonomous driving vehicle in an embodiment of the present invention, the straight-line steering angle of the autonomous driving vehicle is dynamically adjusted by adopting a feedback-correction method, thereby improving the path following accuracy of the vehicle.

[0016] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic flow chart of the method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention.

[0019] FIG2 (a) is a diagram showing the relationship between the lateral deviation of an 8-ton uniform load condition and the current speed and travel distance of the method for dynamically adjusting the steering angle of an autonomous driving vehicle in a straight line provided by the present invention.

[0020] FIG2( b ) is a diagram showing the relationship between the central angle correction value of the 8-ton load uniform working condition and the current speed and driving distance of the automatic driving vehicle straight-ahead steering angle dynamic adjustment method provided by the present invention.

[0021] FIG3 (a) is a diagram showing the relationship between the lateral deviation of an 8-ton uneven load condition and the current speed and travel distance of the method for dynamically adjusting the steering angle of an autonomous driving vehicle traveling straight ahead provided by the present invention.

[0022] FIG3( b ) is a diagram showing the relationship between the central angle correction value of the 8-ton uneven load condition and the current speed and driving distance of the method for dynamically adjusting the steering angle of the automatic driving vehicle in straight driving provided by the present invention. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme in the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0024] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0025] Figure 1 It is a schematic flow chart of the method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention.

[0026] The present invention provides a method for dynamically adjusting the steering angle of an automatic driving vehicle, comprising the following steps: S1: Determine the driving route and multiple target path points corresponding to the driving route P j ,in, P j For the j target waypoints, j The value is an integer greater than or equal to 1; S2: Determine the current coordinate point of the vehicle Q , calculate the current coordinate point Q and each target path point P j The distance between l j ; S3: Identify the current coordinate point Q and each target path point P j The distance between l j The minimum value in l i And determine the target path point corresponding to the minimum value P j As a reference point P i , the driving heading corresponding to the reference point is used as the reference heading of the vehicle, and the curvature of the driving route corresponding to the reference point is used as the current coordinate point on the driving route of the vehicle Q The reference curvature at ; S4: Calculate the lateral deviation and heading deviation of the vehicle according to the coordinates and heading of the vehicle and the reference point; S5: obtaining the current speed of the vehicle, determining whether the current speed of the vehicle, the lateral deviation, the heading deviation and the reference curvature meet the set conditions, and returning to step S2 if the set conditions are not met; S6: if the set conditions are met, the lateral deviation value of the vehicle and the cumulative lateral deviation amount of the vehicle are recorded, and it is determined whether the cumulative lateral deviation amount reaches the cumulative lateral deviation amount threshold of the vehicle, and if not, the process returns to step S2; S7: after reaching the cumulative lateral deviation threshold of the vehicle, calculating the average lateral deviation according to the recorded lateral deviation value of the vehicle and the cumulative lateral deviation of the vehicle, when the absolute value of the average lateral deviation is less than the lateral deviation threshold, returning to step S2; S8: When the absolute value of the average lateral deviation is not less than the lateral deviation threshold, the straight-ahead steering angle of the vehicle is adjusted according to the average lateral deviation. After the adjustment is completed, the vehicle starts to travel.

[0027] In this embodiment, the straight-ahead steering angle of the autonomous driving vehicle is dynamically adjusted by adopting a feedback-correction method, thereby improving the path following accuracy of the vehicle.

[0028] According to some embodiments of the present invention, after the starting point and the end point of the vehicle are determined, a plurality of target path points are generated according to the pre-stored data of the vehicle, and the distance from the current coordinate point of the current vehicle to each target path point is calculated according to the current coordinate point of the vehicle, and the target path point corresponding to the minimum value is determined as a reference point, and the lateral deviation and heading deviation of the vehicle are calculated to determine whether the set conditions are met. If the set conditions are not met, the second step is returned to recalculate, and the lateral deviation is not recorded until the set conditions are met to improve the calculation accuracy of the lateral deviation. The data of the lateral deviation are recorded multiple times to obtain the average value to obtain the average lateral deviation, so as to reduce the error of the lateral deviation in the calculation process, thereby improving the control accuracy of the steering angle. If the absolute value of the average lateral deviation is small, the steering angle is not adjusted. After exceeding the lateral deviation threshold, the steering angle is adjusted according to the average lateral deviation.

[0029] According to some preferred embodiments of the present invention, the threshold value of the accumulated lateral deviation quantity of the vehicle is between 100 and 300.

[0030] According to some preferred embodiments of the present invention, the lateral deviation threshold value ranges from 0.1m to 0.12m.

[0031] According to some preferred embodiments of the present invention, the vehicle speed ranges from 20 km / h to 40 km / h.

[0032] According to a method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention, S2 comprises the following steps: Calculate the current coordinate point Qand each target path point P j The distance between l j , the formula is as follows: in, The current coordinate point of the vehicle Q Arrive at j The distance to the target path point, Indicates the current coordinate point of the vehicle Q The horizontal axis of Indicates the current coordinate point of the vehicle Q The vertical coordinate of Indicates the target path point P j The horizontal axis of Indicates the target path point P j The vertical coordinate of j The value is an integer greater than or equal to 1.

[0033] According to a method for dynamically adjusting the steering angle of an autonomous driving vehicle in a straight line provided by the present invention, the current coordinate point is identified. Q and each target path point P j The distance between l j The minimum value in l i Use the following formula: in, The current coordinate point of the vehicle Q The distance to the last target waypoint, As reference point P i The sequence number of the corresponding target path point, The value is an integer greater than or equal to 1.

[0034] According to a method for dynamically adjusting the steering angle of an autonomous driving vehicle traveling straight ahead provided by the present invention, the lateral deviation is calculated using the following formula: in, Indicates the lateral deviation of the vehicle, Indicates the current coordinate point of the vehicle Q The vertical coordinate of y i Indicates reference point P i The vertical coordinate of Indicates reference point Pi The heading angle, X Indicates the current coordinate point of the vehicle Q The horizontal axis of x i Indicates reference point P i The horizontal axis of .

[0035] According to a method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention, the heading deviation is calculated using the following formula: in, Indicates the vehicle's heading deviation, Indicates the current heading angle of the vehicle. Indicates reference point P i The heading angle.

[0036] According to a method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention, S5 comprises the following steps: Determine a vehicle speed threshold lower limit, a lateral deviation threshold lower limit, a heading deviation threshold upper limit, and a reference curvature threshold upper limit, and set conditions to simultaneously satisfy the following conditions: the current speed of the vehicle is not less than the vehicle speed threshold lower limit, the lateral deviation is not less than the lateral deviation threshold lower limit, the heading deviation is not greater than the heading deviation threshold upper limit, and the reference curvature is not greater than the reference curvature threshold upper limit.

[0037] According to some embodiments of the present invention, the expression satisfying the set condition is as follows: in, is the current speed of the vehicle, is the lower threshold of vehicle speed, is the lower limit of the lateral deviation threshold, is the upper limit of the heading deviation threshold, is the upper limit of the reference curvature threshold, As reference point P i Corresponding to the curvature of the driving route.

[0038] According to some preferred embodiments of the present invention, the heading deviation threshold ranges from 0 degrees to 5 degrees.

[0039] According to some preferred embodiments of the present invention, the reference curvature threshold ranges from 0.0005 to 0.001.

[0040] According to a method for dynamically adjusting the steering angle of an autonomous driving vehicle traveling straight ahead provided by the present invention, the average lateral deviation is calculated using the following formula: in, is the average lateral deviation, For the record r The lateral deviation value, r To record the cumulative lateral deviation of the vehicle, is the cumulative lateral deviation threshold of the vehicle.

[0041] According to a method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention, adjusting the straight-ahead steering angle of the vehicle comprises the following steps: The basic adjustment value is set. If the average lateral deviation is a positive value, the basic adjustment value is added to the straight-ahead steering angle. If the average lateral deviation is a negative value, the basic adjustment value is subtracted from the straight-ahead steering angle.

[0042] According to some embodiments of the present invention, the straight-ahead steering angle is calculated using the following formula: in, is the straight-ahead steering angle, is the straight-ahead steering angle before adjustment, is the average lateral deviation, Adjust the value as the base.

[0043] According to a method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention, the basic adjustment value ranges from 0.01% to 0.05% of the straight-ahead steering angle.

[0044] According to a method for dynamically adjusting the straight-ahead steering angle of an autonomous driving vehicle provided by the present invention, S7 includes the following steps: after calculating the average lateral deviation, deleting the recorded lateral deviation data, and recording the current lateral deviation data.

[0045] The technical solution of the present invention is further explained below in conjunction with a specific embodiment. It should be noted that this specific embodiment is only for those skilled in the art to better understand the technical solution of the present invention, and should not be regarded as an unreasonable limitation on the protection scope of the present invention.

[0046] Embodiment 1 The parameter settings of the present invention are shown in Table 1.

[0047] Table 1

[0048] First, determine the target path point closest to the current vehicle position, then calculate the lateral deviation and heading deviation between the vehicle and the path, and determine the reference curvature; then, based on the above information, determine whether the straight-ahead steering angle needs to be adjusted; if adjustment is required, determine the adjustment direction based on the deviation information and add it to the straight-ahead steering angle history value. The present invention is tested on a real vehicle platform.

[0049] Test results (1) 8 tons uniform load condition Figure 2 (a) is a graph showing the relationship between the lateral deviation of the 8-ton uniform load condition and the current speed and travel distance of the dynamic adjustment method for the straight-line steering angle of the autonomous driving vehicle provided by the present invention. Figure 2 (b) is a graph showing the relationship between the central angle correction of the 8-ton uniform load condition and the current speed and travel distance of the dynamic adjustment method for the straight-line steering angle of the autonomous driving vehicle provided by the present invention.

[0050] 8 tons of cargo was loaded and evenly distributed on both sides of the vehicle. The target speed was set to 70 km / h. The experimental vehicle turned on the automatic driving function and automatically followed the center line of the road. The test results are shown in Figure 2 (a) and Figure 2 (b).

[0051] During the whole process, as shown in Figure 2 (a), the lateral deviation is less than 0.3 m, as shown in Figure 2 (b), but the correction of the center angle changes with the speed. At 70 km / h, the correction value is 1.18%.

[0052] (2) 8 tons uneven load condition Figure 3 (a) is a graph showing the relationship between the lateral deviation of the 8-ton uneven load condition and the current speed and travel distance of the dynamic adjustment method for the steering angle of the automatic driving vehicle in straight driving provided by the present invention. Figure 3 (b) is a graph showing the relationship between the central angle correction of the 8-ton uneven load condition and the current speed and travel distance of the dynamic adjustment method for the steering angle of the automatic driving vehicle in straight driving provided by the present invention.

[0053] 8 tons of cargo was loaded, with 4.5 tons on the left and 3.5 tons on the right. The target speed was set to 70 km / h. The experimental vehicle turned on the automatic driving function and automatically followed the center line of the road. The test results are shown in Figure 3 (a) and Figure 3 (b).

[0054] During the whole process, as shown in Figure 3 (a), the lateral deviation is less than 0.3m, as shown in Figure 3 (b), but the correction amount of the center angle changes with the change of speed. At 70km / h, the correction value is 0.5%. Compared with the uniform load, the correction amount is reduced and converges to the right (positive value is to the left, negative value is to the right), effectively eliminating the problem of the vehicle driving to the left when the load is "heavy on the left and light on the right".

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for dynamically adjusting the steering angle of an autonomous driving vehicle, characterized in that: The steps include: S1: Determine the driving route and multiple target path points corresponding to the driving route P j ,in, P j For the j target waypoints, j The value is an integer greater than or equal to 1; S2: Determine the current coordinate point of the vehicle Q , calculate the current coordinate point Q and each target path point P j The distance between l j ; S3: Identify the current coordinate point Q and each target path point P j The distance between l j The minimum value in l i And determine the target path point corresponding to the minimum value P j As a reference point P i , the reference point P i The corresponding driving heading is used as the reference heading of the vehicle, and the reference point P i The curvature of the corresponding driving route is used as the current coordinate point on the vehicle driving route Q The reference curvature at ; S4: Based on vehicle and reference point P i The coordinates and heading of the vehicle are used to calculate the lateral deviation and heading deviation of the vehicle; S5: obtaining the current speed of the vehicle, determining whether the current speed of the vehicle, the lateral deviation, the heading deviation and the reference curvature meet the set conditions, and returning to step S2 if the set conditions are not met; S6: if the set conditions are met, the lateral deviation value of the vehicle and the cumulative lateral deviation amount of the vehicle are recorded, and it is determined whether the cumulative lateral deviation amount reaches the cumulative lateral deviation amount threshold of the vehicle, and if not, the process returns to step S2; S7: after reaching the cumulative lateral deviation threshold of the vehicle, calculating the average lateral deviation according to the recorded lateral deviation value of the vehicle and the cumulative lateral deviation number of the vehicle, when the absolute value of the average lateral deviation is less than the lateral deviation threshold, returning to step S2; S8: When the absolute value of the average lateral deviation is not less than the lateral deviation threshold, the straight-ahead steering angle of the vehicle is adjusted according to the average lateral deviation. After the adjustment is completed, the vehicle starts to travel.

2. The method for dynamically adjusting the steering angle of an automatic driving vehicle traveling straight ahead according to claim 1, characterized in that: S2 includes the following steps: Calculate the current coordinate point Q and each target path point P j The distance between l j , the formula is as follows: in, The current coordinate point of the vehicle Q Arrive at j The distance to the target path point, Indicates the current coordinate point of the vehicle Q The horizontal axis of Indicates the current coordinate point of the vehicle Q The vertical coordinate of Indicates the target path point P j The horizontal axis of Indicates the target path point P j The vertical coordinate of .

3. The method for dynamically adjusting the steering angle of an automatic driving vehicle traveling straight ahead according to claim 2, characterized in that: Identify the current coordinate point Q and each target path point P j The distance between l j The minimum value in l i Use the following formula: in, The current coordinate point of the vehicle Q The distance to the last target waypoint, As reference point P i The sequence number of the corresponding target path point, The value is an integer greater than or equal to 1.

4. The method for dynamically adjusting the steering angle of an automatic driving vehicle traveling straight ahead according to claim 3, characterized in that: The following formula is used to calculate the lateral deviation: in, Indicates the lateral deviation of the vehicle, Indicates the current coordinate point of the vehicle Q The vertical coordinate of y i Indicates reference point P i The vertical coordinate of Indicates reference point P i The heading angle, X Indicates the current coordinate point of the vehicle Q The horizontal axis of x i Indicates reference point P i The horizontal axis of .

5. The method for dynamically adjusting the steering angle of an automatic driving vehicle traveling straight ahead according to claim 4, characterized in that: The following formula is used to calculate the heading deviation: in, Indicates the vehicle's heading deviation, Indicates the current heading angle of the vehicle. Indicates reference point P i The heading angle.

6. The method for dynamically adjusting the steering angle of an automatic driving vehicle traveling straight ahead according to claim 5, characterized in that: S5 includes the following steps: Determine a vehicle speed threshold lower limit, a lateral deviation threshold lower limit, a heading deviation threshold upper limit, and a reference curvature threshold upper limit, and set conditions to simultaneously satisfy the following conditions: the current speed of the vehicle is not less than the vehicle speed threshold lower limit, the lateral deviation is not less than the lateral deviation threshold lower limit, the heading deviation is not greater than the heading deviation threshold upper limit, and the reference curvature is not greater than the reference curvature threshold upper limit.

7. The method for dynamically adjusting the steering angle of an automatic driving vehicle traveling straight ahead according to claim 6, characterized in that: The average lateral deviation is calculated using the following formula: in, is the average lateral deviation, For the record r The lateral deviation value, r is the cumulative lateral deviation of the vehicle, is the cumulative lateral deviation threshold of the vehicle.

8. The method for dynamically adjusting the steering angle of an automatic driving vehicle traveling straight ahead according to claim 7, characterized in that: Adjusting the vehicle's straight-ahead steering angle includes the following steps: The basic adjustment value is set. If the average lateral deviation is a positive value, the basic adjustment value is added to the straight-ahead steering angle. If the average lateral deviation is a negative value, the basic adjustment value is subtracted from the straight-ahead steering angle.

9. The method for dynamically adjusting the steering angle of an automatic driving vehicle traveling straight ahead according to claim 8, characterized in that: The basic adjustment value ranges from 0.01% to 0.05% of the straight-ahead steering angle.

10. The method for dynamically adjusting the steering angle of an automatic driving vehicle traveling straight ahead according to claim 1, characterized in that: S7 includes the following steps: after calculating the average lateral deviation, deleting the recorded lateral deviation data, and recording the current lateral deviation data.

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