Automatic driving vehicle control method and vehicle

Abstract

The invention provides an automatic driving vehicle control method and a vehicle. The method comprises the steps that the actual vehicle speed and the actual time interval of the vehicle, the actual relative speed of the vehicle and a target vehicle located in front of the vehicle and the actual relative distance between the vehicle and the target vehicle are obtained; determining a basic expected distance according to the actual vehicle speed and the actual time interval of the vehicle; determining a final expected distance according to the basic expected distance, the curvature compensation coefficient and the gradient compensation coefficient; determining a critical value of a preset distance interval according to the final expected distance and the preset speed interval; determining an interval condition corresponding to the actual relative distance, and determining an expected relative speed according to the interval condition and a critical value of a preset speed interval; according to the actual relative speed, the expected relative speed and the actual time interval, the target acceleration of the vehicle is determined, and the vehicle is controlled to run at the target acceleration. According to the invention, the relative distance between the vehicle and the target vehicle is automatically adjusted according to the target acceleration, and the driving efficiency is improved.

Description

Technical Field

[0001] The present application relates to the field of automobile control technology, and more specifically, to an autonomous driving vehicle control method and a vehicle. Background Art

[0002] Currently, during the process of autonomous driving, vehicles need to dynamically adjust acceleration instructions according to different scenarios. The current adaptive cruise control (ACC) system is mainly based on a fixed following distance for control, which lacks flexibility and adaptability.

[0003] Traditional adaptive cruise control (ACC) systems often perform less than ideally in different scenarios. For example, the following distance setting is too rigid and cannot be dynamically adjusted according to actual road conditions, and the acceleration and deceleration control strategy is single, resulting in poor passenger comfort. Summary of the invention

[0004] In view of this, the purpose of the present application is to provide an autonomous driving vehicle control method and a vehicle to overcome at least one of the above-mentioned defects.

[0005] In a first aspect, an embodiment of the present application provides a method for controlling an autonomous driving vehicle, the method comprising: obtaining an actual vehicle speed and actual time distance of the vehicle, an actual relative speed between the vehicle and a target vehicle located in front of the vehicle, and an actual relative distance between the vehicle and the target vehicle; determining a basic expected distance based on the actual vehicle speed and actual time distance of the vehicle; determining a final expected distance based on the basic expected distance, a curvature compensation coefficient, and a slope compensation coefficient; determining a critical value of a preset distance interval based on the final expected distance and a preset speed interval, each preset speed interval corresponding to each preset distance interval; determining an interval situation corresponding to the actual relative distance, determining an expected relative speed based on the interval situation and the critical value of the preset speed interval, different interval situations corresponding to different expected relative speeds; determining a target acceleration of the vehicle based on the actual relative speed, the expected relative speed, and the actual time distance, and controlling the vehicle to travel at the target acceleration.

[0006] In an optional embodiment of the present application, the preset distance interval includes a far-away distance interval and a close-in distance interval, the preset speed interval includes a far-away speed interval and a close-in speed interval, the far-away distance interval corresponds to the far-away speed interval, and the close-in distance interval corresponds to the close-in speed interval, wherein the critical value of the preset distance interval of the vehicle is determined by: determining a comparison result between the actual relative distance and the final expected distance; judging whether the vehicle is in the far-away distance interval based on the comparison result; if the vehicle is in the far-away distance interval, judging whether the vehicle is in the far-away distance interval based on the lower limit value of the far-away speed interval, the first preset penalty speed interval, and the final expected distance; The vehicle is determined according to the speed and the final expected distance, and the upper limit of the distance away interval is determined; the lower limit of the distance away interval is determined according to the upper limit of the distance away interval, the upper limit of the speed away interval, the lower limit of the speed away interval, the second preset penalty speed and the final expected distance; if the vehicle is not in the distance away interval, the lower limit of the distance approaching interval is determined according to the upper limit of the speed approaching interval, the third preset penalty speed and the final expected distance, and the upper limit of the distance approaching interval is determined according to the lower limit of the distance approaching interval, the lower limit of the speed approaching interval, the upper limit of the speed approaching interval, the fourth preset penalty speed and the final expected distance.

[0007] In an optional embodiment of the present application, the target acceleration of the vehicle is determined in the following manner: based on the distance range of the actual relative distance of the vehicle, the distance situation between the vehicle and the target vehicle is determined; for each distance situation, the expected relative speed of the vehicle in the distance situation is determined, and the target acceleration of the vehicle is determined based on the expected relative speed.

[0008] In an optional embodiment of the present application, the distance situation includes a first distance situation, a second distance situation, a third distance situation, a fourth distance situation and a fifth distance situation, wherein the distance situation between the vehicle and the target vehicle is determined according to the distance range in which the actual relative distance of the vehicle is located, including: if the actual relative distance of the vehicle is greater than a preset constant and less than the lower limit of the far distance interval, the distance situation between the vehicle and the target vehicle is determined to be the first distance situation; if the actual relative distance of the vehicle is greater than or equal to the lower limit of the far distance interval and less than or equal to the upper limit of the far distance interval, the distance situation between the vehicle and the target vehicle is determined to be the second distance situation; if the actual relative distance of the vehicle is greater than the upper limit of the far distance interval and less than or equal to the final expected distance, the distance situation between the vehicle and the target vehicle is determined to be the third distance situation; if the actual relative distance of the vehicle is greater than the final expected distance and less than or equal to the lower limit of the approaching distance, the distance situation between the vehicle and the target vehicle is determined to be the fourth distance situation; if the actual relative distance of the vehicle is greater than the lower limit of the approaching distance, the distance situation between the vehicle and the target vehicle is determined to be the fifth distance situation.

[0009] In an optional embodiment of the present application, the target acceleration of the vehicle when the distance between the vehicle and the target vehicle is a first distance condition is determined in the following manner: when it is detected that the actual relative speed is less than the lower limit of the moving-away speed interval, a first difference between the actual relative speed and the lower limit of the moving-away speed interval is calculated, and a ratio of the first difference to the actual time distance is determined, and the ratio of the first difference to the actual time distance is determined as the target acceleration of the vehicle; when it is detected that the actual relative speed is greater than or equal to the lower limit of the moving-away speed interval and less than or equal to the upper limit of the moving-away speed interval, a preset constant is determined as the target acceleration of the vehicle; when it is detected that the actual relative speed is greater than the upper limit of the moving-away speed interval, a second difference between the actual relative speed and the upper limit of the moving-away speed interval is calculated, and a ratio of the second difference to the actual time distance is determined, and the ratio of the second difference to the actual time distance is determined as the target acceleration of the vehicle.

[0010] In an optional embodiment of the present application, the target acceleration of the vehicle when the distance between the vehicle and the target vehicle is the second distance condition is determined in the following manner: the first expected relative speed is calculated according to the lower limit of the away speed interval, the second preset penalty speed, the actual relative distance, the upper limit of the away distance interval and the final expected distance; when it is detected that the actual relative speed is less than the lower limit of the away speed interval, the third difference between the actual relative speed and the lower limit of the away speed interval is calculated, and the ratio of the third difference to the actual time distance is determined, and the ratio of the third difference to the actual time distance is determined as the target acceleration of the vehicle; when it is detected that the actual relative speed is greater than or equal to the lower limit of the away speed interval and less than or equal to the first expected relative speed, a preset constant is determined as the target acceleration of the vehicle; when it is detected that the actual relative speed is greater than the first expected relative speed, the fourth difference between the actual relative speed and the first expected relative speed is calculated, and the ratio of the fourth difference to the actual time distance is determined, and the ratio of the fourth difference to the actual time distance is determined as the target acceleration of the vehicle.

[0011] In an optional embodiment of the present application, the target acceleration of the vehicle when the distance between the vehicle and the target vehicle is a third distance condition is determined in the following manner: a second expected relative speed is calculated based on the first preset penalty speed, the actual relative distance and the final expected distance; a fifth difference between the actual relative speed and the second expected relative speed is calculated, and a ratio of the fifth difference to the actual time distance is determined, and the ratio of the fifth difference to the actual time distance is determined as the target acceleration of the vehicle.

[0012] In an optional embodiment of the present application, the target acceleration of the vehicle when the distance between the vehicle and the target vehicle is the fourth distance condition is determined in the following manner: a third expected relative speed is calculated based on the third preset penalty speed, the actual relative distance and the final expected distance; a sixth difference between the actual relative speed and the third expected relative speed is calculated, and a ratio of the sixth difference to the actual time distance is determined, and the ratio of the sixth difference to the actual time distance is determined as the target acceleration of the vehicle.

[0013] In an optional embodiment of the present application, the target acceleration of the vehicle when the distance between the vehicle and the target vehicle is the fifth distance condition is determined in the following manner: according to the upper limit of the approaching speed interval, the fourth preset penalty speed, the actual relative distance, the lower limit of the approaching distance interval and the final expected distance, the fourth expected relative speed is calculated; when it is detected that the actual relative speed is less than the fourth expected relative speed, the seventh difference between the actual relative speed and the fourth expected relative speed is calculated, and the ratio of the seventh difference to the actual time distance is determined, and the ratio of the seventh difference to the actual time distance is determined as the target acceleration of the vehicle; when it is detected that the actual relative speed is greater than or equal to the fourth expected relative speed and less than or equal to the upper limit of the approaching speed interval, a preset constant is determined as the target acceleration of the vehicle; when it is detected that the actual relative speed is greater than the upper limit of the approaching speed interval, the eighth difference between the actual relative speed and the upper limit of the approaching speed interval is calculated, and the ratio of the eighth difference to the actual time distance is determined, and the ratio of the eighth difference to the actual time distance is determined as the target acceleration of the vehicle.

[0014] In a second aspect, an embodiment of the present application also provides a vehicle, which includes the autonomous driving vehicle control method as described above.

[0015] The automatic driving vehicle control method and vehicle provided by the embodiment of the present application obtain the actual speed and actual headway of the vehicle, the actual relative speed between the vehicle and the target vehicle located in front of the vehicle, and the actual relative distance between the vehicle and the target vehicle; determine the basic expected distance according to the actual speed and actual headway of the vehicle; determine the final expected distance according to the basic expected distance, the curvature compensation coefficient, and the slope compensation coefficient; determine the critical value of the preset distance interval according to the final expected distance and the preset speed interval; determine the interval situation corresponding to the actual relative distance, and determine the expected relative speed according to the interval situation and the critical value of the preset speed interval; determine the target acceleration of the vehicle according to the actual relative speed, the expected relative speed, and the actual headway, and control the vehicle to travel at the target acceleration. Through this application, the relative distance between the vehicle and the target vehicle is automatically adjusted according to the target acceleration to improve driving efficiency.

[0016] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A flowchart of the automatic driving vehicle control method provided in an embodiment of the present application;

[0019] Figure 2 A flow chart for determining a target acceleration of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0020] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application usually described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, each other embodiment obtained by those skilled in the art without making creative work belongs to the scope of protection of the present application.

[0021] First, the application scenarios to which the present application is applicable are introduced. The present application can be applied in the field of automobile control technology.

[0022] Research has found that during the process of autonomous driving, the vehicle needs to dynamically adjust the acceleration command according to different scenarios. The current adaptive cruise control (ACC) system is mainly based on a fixed following distance for control, which lacks flexibility and adaptability.

[0023] In addition, the performance of traditional adaptive cruise control (ACC) systems in different scenarios is often not ideal. For example, the following distance setting is too rigid and cannot be dynamically adjusted according to actual road conditions, and the acceleration and deceleration control strategy is single, resulting in poor passenger comfort.

[0024] Based on this, the embodiments of the present application provide an autonomous driving vehicle control method and a vehicle, which obtain the actual speed and actual time distance of the vehicle, the actual relative speed of the vehicle and a target vehicle located in front of the vehicle, and the actual relative distance between the vehicle and the target vehicle; determine the basic expected distance according to the actual speed and actual time distance of the vehicle; determine the final expected distance according to the basic expected distance, a curvature compensation coefficient, and a slope compensation coefficient; determine the critical value of the preset distance interval according to the final expected distance and the preset speed interval; determine the interval situation corresponding to the actual relative distance, and determine the expected relative speed according to the interval situation and the critical value of the preset speed interval; determine the target acceleration of the vehicle according to the actual relative speed, the expected relative speed, and the actual time distance, and control the vehicle to travel at the target acceleration. Through this application, the relative distance between the target vehicle and the target vehicle is automatically adjusted according to the target acceleration to improve driving efficiency. This application can dynamically adapt to real-time road conditions and vehicle status, intelligently adjust acceleration planning, improve the flexibility and accuracy of cruise control, and can adapt to different driving modes and environments to ensure stable and reliable cruise control in all situations. By accurately calculating the acceleration instructions at different relative distances and relative speeds, the riding comfort is enhanced. This application can also consider the path curvature and slope, appropriately increase the following distance, and effectively prevent the occurrence of safety accidents such as rear-end collisions. The fuel and electricity economy and traffic efficiency are optimized. This application can improve driving efficiency as much as possible while ensuring safety, reduce unnecessary acceleration and braking through intelligent control, thereby optimizing fuel or electricity economy. At the same time, by optimizing the cruise strategy, the system also improves traffic efficiency and reduces congestion and waiting time.

[0025] See also Figure 1 , Figure 1 This is a flow chart of the automatic driving vehicle control method provided in the embodiment of the present application. Figure 1 As shown in the figure, the automatic driving vehicle control method provided by the embodiment of the present application includes:

[0026] S101. Acquire the actual speed and actual headway of the vehicle, the actual relative speed between the vehicle and a target vehicle located in front of the vehicle, and the actual relative distance between the vehicle and the target vehicle.

[0027] Among them, the vehicle is usually equipped with wheel speed sensors, GPS sensors, etc. to determine the actual speed of the vehicle.

[0028] For example, the vehicle speed can be calculated by measuring the rotation speed of the wheel through a wheel speed sensor, and the vehicle speed and position can be calculated by receiving satellite signals using the global positioning system through a GPS sensor. The accuracy of the vehicle speed calculation can be improved by combining multiple sensor data and using filtering and fusion algorithms.

[0029] Here, the actual time distance refers to the time distance between the current vehicle and the target vehicle, which is usually defined as the time required for the current vehicle to reach the current position of the preceding vehicle. Here, the target vehicle is the vehicle located in front of the current vehicle and closest to the current vehicle.

[0030] Preferably, radar, laser radar (LiDAR), camera, etc. can be used to detect the position and speed of the vehicle in front. Radar transmits radio waves and receives reflected signals to measure distance and speed. LiDAR calculates distance by emitting laser beams and measuring reflection time. The camera can also use image processing technology to identify the vehicle in front and calculate the distance and speed through image analysis.

[0031] The difference between the actual speed of the vehicle and the speed of the target vehicle in front is the actual relative speed.

[0032] Here, sensors such as radar, LiDAR and cameras can be used to measure distance. Radar and LiDAR calculate the distance by measuring the round-trip time of the signal. The camera uses image processing technology to identify the vehicle in front and calculate the distance using the proportional relationship in the image.

[0033] In order to improve the accuracy and reliability of data, data from different sensors are usually fused. For example, GPS and wheel speed sensor data are combined to calculate vehicle speed, and radar and camera data are combined to measure distance and speed. At the same time, sensor data is verified and filtered to remove noise and outliers. For example, algorithms such as Kalman filters are used to smooth data.

[0034] In the autonomous driving system, these parameters are crucial to achieving safe and efficient autonomous driving. By monitoring and calculating these parameters in real time, the autonomous driving system can make correct decisions, such as maintaining a safe distance and avoiding collisions. For example, the adaptive cruise control (ACC) system needs to obtain information such as vehicle speed and relative distance in real time to automatically adjust the vehicle speed and distance according to the speed and distance of the vehicle in front.

[0035] In summary, obtaining the vehicle's actual speed, actual time interval, actual relative speed and actual relative distance requires the use of a variety of sensors and data processing technologies. Through multi-sensor fusion and verification and filtering algorithms, the accuracy and reliability of the data can be improved, providing strong support for applications such as autonomous driving and ADAS.

[0036] S102: Determine a basic expected distance based on the actual vehicle speed and actual time distance, and expand it.

[0037] Here, the actual vehicle speed is the current speed of the vehicle, usually in kilometers per hour (km / h) or miles per hour (mph).

[0038] The actual time distance is the time distance between the vehicle and the target vehicle, that is, the time required for the current vehicle to reach the current position of the front vehicle, usually in seconds (s).

[0039] The actual time distance is divided into different gears according to factors such as road conditions, traffic conditions and driver preferences. For example, the time distance can be divided into three gears: short, medium and long, corresponding to different safety distance requirements. These gears may be defined by preset thresholds.

[0040] According to the actual vehicle speed and actual time distance t gap The basic expected distance d is obtained from the table base Generally, the higher the speed, the greater the expected distance. In addition, the actual time distance can be set according to the driver's habits, for example: the time distance t for following a vehicle at close range gap_near =1.2s, medium distance following time t gap_mid =1.8s, original distance following time t gap_far =2.4s.

[0041] The basic expected distance is usually determined by multiplying the actual vehicle speed by the actual time distance. This formula can be expressed as: basic expected distance = actual vehicle speed × actual time distance.

[0042] The product here gives a relative distance based on time and speed, which reflects how much distance the vehicle needs to maintain at the current speed to ensure that there is enough time to brake or avoid in an emergency.

[0043] The Adaptive Cruise Control (ACC) system needs to calculate and adjust the distance to the vehicle in front in real time to maintain a safe following distance. The basic expected distance can be used as a benchmark for the ACC system to adjust the distance. Determining the basic expected distance is a process that comprehensively considers vehicle speed, time distance and other related factors. Through precise calculation and flexible adjustment, it can ensure that the vehicle maintains a safe and efficient driving state in autonomous driving or ADAS applications.

[0044] S103: Determine a final expected distance according to the basic expected distance, the curvature compensation coefficient, and the slope compensation coefficient.

[0045] In autonomous driving systems and advanced driver assistance systems (ADAS), the final expected distance is not only determined by the basic expected distance, but also needs to take into account dynamic environmental factors such as road curvature and slope. These factors are adjusted through curvature compensation coefficients and slope compensation coefficients to ensure that the vehicle can maintain a safe and comfortable driving distance under various road conditions.

[0046] The curvature compensation coefficient is used to adjust the additional safety distance required due to road curvature. The greater the road curvature, the greater the safety distance required when the vehicle is driving, in order to avoid the risk of collision caused by turning too sharply.

[0047] The curvature compensation coefficient can be calculated by measuring the road curvature (such as the radius of curvature). Different curvature values ​​correspond to different compensation coefficients, which are usually determined by preset rules or algorithms.

[0048] In this step, the curvature compensation coefficient is calculated by using a hyperbolic tangent function in this application to achieve a smooth transition of the curvature compensation coefficient at different curvatures. The curvature compensation coefficient is determined by the following method:

[0049]

[0050] Among them, C curve (k) is the curvature compensation coefficient of the vehicle, K high is the high curvature compensation gain value, α is the curvature high threshold smoothing factor, k is the actual curvature of the vehicle, k high is the high curvature threshold, K low is the low curvature compensation gain value, β is the curvature low threshold smoothing factor, k low is the low isocurvature threshold.

[0051] Specifically, the slope compensation coefficient is also calculated using a hyperbolic tangent function with a smooth transition, and the slope compensation coefficient is determined by the following formula:

[0052]

[0053] Among them, C slope (θ) is the vehicle's slope compensation coefficient, K up is the uphill compensation gain value, γ is the slope smoothing factor, θ is the actual slope value of the vehicle, and θ up is the uphill threshold, K down is the downhill compensation gain value, θ down is the downhill threshold.

[0054] The slope compensation coefficient is used to adjust the safety distance that needs to be adjusted due to changes in road slope. When going uphill, the vehicle requires greater power to maintain speed, so the safety distance may need to be increased to cope with potential braking needs; when going downhill, the vehicle may accelerate due to gravity acceleration, and the safety distance also needs to be increased to ensure safety.

[0055] The slope compensation coefficient can be calculated by the actual measured value of the road slope (such as slope percentage or inclination angle). Different slope values ​​correspond to different compensation coefficients, which are also determined by preset rules or algorithms.

[0056] By calculating the product of the curvature compensation coefficient, the slope compensation coefficient and the basic expected distance, the safety distance that needs to be adjusted due to road curvature and road slope changes can be obtained.

[0057] When going uphill, the vehicle needs to overcome gravity to do work, resulting in a relatively weaker power output. This means that the vehicle may need a longer distance and time to accelerate or maintain the current speed, especially in heavily loaded or high-altitude areas. Therefore, appropriately increasing the following distance can provide the driver with sufficient reaction time and braking distance to prevent rear-end collisions caused by insufficient power.

[0058] Here, the slope compensation scheme calculates the compensation factor when going uphill by monitoring the vehicle's real-time speed and acceleration data, as well as the road slope information. This factor will dynamically increase the basic expected distance to adapt to the power requirements when going uphill.

[0059] When going downhill, the vehicle is accelerated by gravity and the speed tends to increase. Although the power demand of the vehicle is reduced when going downhill, the braking distance will increase significantly, especially on slippery or uneven roads. Therefore, it is necessary to significantly increase the following distance to ensure that there is enough time and space to brake in an emergency.

[0060] Similar to the uphill situation, the slope compensation scheme will calculate the compensation coefficient for the downhill situation based on the road slope, vehicle speed and acceleration data when going downhill. This coefficient will be larger than when going uphill to further increase the basic expected distance and ensure safety when going downhill.

[0061] When driving on a flat road or a road with a small slope, the vehicle's power output and braking performance are relatively stable, and no additional following distance is required. Maintaining a normal following distance can improve road traffic efficiency and ensure driving safety.

[0062] The slope compensation scheme monitors the road slope information in real time and keeps the compensation coefficient close to 1 (i.e. no additional compensation) when the slope changes little, thereby maintaining the basic expected distance unchanged.

[0063] This smooth-transition slope compensation solution is widely used in autonomous driving and ADAS functions such as adaptive cruise control (ACC), forward collision warning (FCW) and automatic emergency braking (AEB).

[0064] By dynamically adjusting the following distance to adapt to changes in different road conditions, this solution can significantly improve driving safety, comfort and road efficiency. At the same time, it can also reduce the risk of traffic accidents caused by driver misjudgment or untimely response.

[0065] The final desired distance is determined by the following formula:

[0066] d desired＝d base ×C curve (κ)×C slope (θ)

[0067] Among them, d desired is the final expected distance, d base is the basic expected distance, C curve (k) is the curvature compensation coefficient of the vehicle, C slope (θ) is the slope compensation coefficient of the vehicle.

[0068] S104: Determine a critical value of the preset distance interval according to the final expected distance and the preset speed interval.

[0069] Here, each preset speed interval corresponds to each preset distance interval, the preset distance interval includes a far distance interval and a near distance interval, the preset speed interval includes a far speed interval and a near speed interval, the far distance interval corresponds to the far speed interval, and the near distance interval corresponds to the near speed interval.

[0070] Distance interval and speed interval: When the actual relative distance of the vehicle is less than the final expected distance, the vehicle is considered to be in the distance interval. At this time, the vehicle should take action to increase the distance from the target vehicle, but it does not necessarily need to brake or slow down, as long as the distance between the two vehicles can be gradually increased. Correspondingly, the speed interval defines the upper and lower limits of the speed interval that the vehicle can use in such situations.

[0071] Preferably, the range of the distance interval corresponding to the speed interval is [v openLow , v openHigh ], that is, the relative speed required to move away from the vehicle in front, for example: [3, 5].

[0072] Approaching distance interval and approaching speed interval: When the actual relative distance of the vehicle is greater than or equal to the final expected distance, the vehicle is considered to be in the approaching distance interval. At this time, the vehicle should take measures to close the distance with the target vehicle, but it does not necessarily need to step on the accelerator to accelerate, as long as the distance between the two vehicles can be gradually reduced to the expected level. The approaching speed interval specifies the upper and lower limits of the approaching speed interval that the vehicle can use in such situations.

[0073] Preferably, the approaching speed interval corresponding to the approaching distance interval has a value range of [v closeLow , v closeHigh ], that is, the relative speed required to approach the vehicle in front, for example: [-5, -3].

[0074] Specifically, the critical value of the preset distance interval of the vehicle is determined by:

[0075] Determine the actual relative distance and the comparison result of the final expected distance;

[0076] Here, the comparison result is determined in the following way:

[0077] Determine whether the actual relative distance is less than the final expected distance;

[0078] If the actual relative distance is less than the final expected distance, the comparison result is determined to be that the distance between the vehicle and the target vehicle is in the far distance interval; if the actual relative distance is not less than the final expected distance, the comparison result is determined to be that the distance between the vehicle and the target vehicle is in the close distance interval.

[0079] According to the comparison result, it is determined whether the vehicle is in a far distance interval;

[0080] If the vehicle is in the away distance interval, the away distance interval upper limit is determined according to the away speed interval lower limit, the first preset penalty speed and the final expected distance, and the away distance interval lower limit is determined according to the away distance interval upper limit, the away speed interval upper limit, the away speed interval lower limit, the second preset penalty speed and the final expected distance;

[0081] Here, the critical value of the distance interval is determined as follows:

[0082] When the vehicle is in the distance interval, we first calculate the upper limit of the distance interval according to the lower limit of the speed interval, the first preset penalty speed and the final expected distance. Here, the first preset penalty speed is a speed limit set to prevent the vehicle from pulling away from the vehicle ahead too quickly.

[0083] In an optional embodiment, all penalty speed settings of the present application are intended to provide a certain speed limit when the distance is too far to avoid potential safety hazards caused by an excessively fast approach speed. The value of the penalty speed can be an empirical value or defined according to demand, which will not be elaborated later.

[0084] The upper limit of the distance interval is calculated using the following formula:

[0085]

[0086] Among them, d openUp is the upper limit of the distance interval, v openLow To stay away from the lower limit of the speed range, v openLowPunish is the first preset penalty speed, d desired is the final expected distance.

[0087] Preferably, wherein v openLowPunishWhen the threshold is low, the penalty speed for increasing the distance between the two vehicles is, for example, -10 m / s. In addition, the lower limit of the speed interval is used to calculate the upper limit of the distance interval, so the first preset penalty speed corresponds to the low threshold.

[0088] Next, we use the upper limit of the distance interval, the upper and lower limits of the speed interval, the second preset penalty speed, and the final expected distance to calculate the lower limit of the distance interval. The second preset penalty speed is to ensure that the vehicle will not be too slow in the process of pulling away, so as not to affect the smooth flow of traffic.

[0089] The lower limit of the distance interval is calculated by the following formula:

[0090]

[0091] Among them, d openLow is the lower limit of the distance interval, d openUp is the upper limit of the distance interval, v openHigh To be far away from the upper limit of the speed range, v openLow To stay away from the lower limit of the speed range, v openUpPunish is the second preset penalty speed, d desired is the final expected distance.

[0092] Preferably, wherein v openUpPunish The penalty speed for increasing the distance between the two vehicles when the threshold is high, for example: -5m / s. Similarly, the upper limit of the speed interval is used to calculate the lower limit of the distance interval, so the second preset penalty speed corresponds to the high threshold.

[0093] If the vehicle is not in the far distance interval, it means that the vehicle is in the approaching distance interval. The lower limit value of the approaching distance interval is determined according to the upper limit value of the approaching speed interval, the third preset penalty speed and the final expected distance. The upper limit value of the approaching distance interval is determined according to the lower limit value of the approaching distance interval, the lower limit value of the approaching speed interval, the upper limit value of the approaching speed interval, the fourth preset penalty speed and the final expected distance.

[0094] Here, the critical value of the proximity distance interval is determined:

[0095] When the vehicle is not in the far distance interval, that is, in the approaching distance interval, we calculate the lower limit of the approaching distance interval according to the upper limit of the approaching speed interval, the third preset penalty speed and the final expected distance. The third preset penalty speed is a speed limit set to prevent the vehicle from approaching the front vehicle too quickly.

[0096] The lower limit of the approach distance interval is calculated using the following formula:

[0097]

[0098] Among them, d closeLow To approach the lower limit of the distance interval, v closeHigh is close to the upper limit of the speed range, v closeLowPunish is the third preset penalty speed, d desired is the final expected distance.

[0099] Preferably, wherein v closeLowPunish The penalty speed for closing the distance between the two vehicles when the threshold is low, for example: -5m / s. Here, the upper limit of the approaching speed interval is used to calculate the lower limit of the approaching distance interval. Correspondingly, the third preset penalty speed corresponds to the low threshold.

[0100] Then, we use the lower limit of the approach distance interval, the lower and upper limits of the approach speed interval, the fourth preset penalty speed, and the final expected distance to calculate the upper limit of the approach distance interval. The fourth preset penalty speed is to ensure that the vehicle will not be too cautious in the process of closing the distance, so as not to reduce the road traffic efficiency.

[0101] The upper limit of the approach distance interval is calculated using the following formula:

[0102]

[0103] Among them, d closeUp is close to the upper limit of the distance interval, d closeLow To approach the lower limit of the distance interval, v closeLow is the lower limit of the approaching speed range, v closeHigh is close to the upper limit of the speed range, v closeUpPunish The fourth preset penalty speed, d desired is the final expected distance.

[0104] Preferably, wherein v closeUpPunish The penalty speed for closing the distance between the two vehicles when the threshold is high, for example: -5m / s. Here, the lower limit of the approaching speed interval is used to calculate the upper limit of the approaching distance interval. Correspondingly, the third preset penalty speed corresponds to the low threshold.

[0105] S105: Determine the interval situation corresponding to the actual relative distance, and determine the expected relative speed according to the interval situation and the critical value of the preset speed interval.

[0106] Different interval conditions correspond to different expected relative speeds.

[0107] Here, the expected relative speed is calculated according to the actual relative distance, and then the target acceleration can be calculated by the difference between the actual relative speed and the expected relative speed and the actual time interval.

[0108] S106: Determine a target acceleration of the vehicle according to the actual relative speed, the expected relative speed, and the actual time interval, and control the vehicle to travel at the target acceleration.

[0109] See also Figure 2 , Figure 2 This is a flow chart for determining the target acceleration of a vehicle provided in an embodiment of the present application. Figure 2 As shown in the figure, the automatic driving vehicle control method provided by the embodiment of the present application includes:

[0110] Specifically, the target acceleration of the vehicle is determined by:

[0111] S201. Determine the distance between the vehicle and the target vehicle according to the distance range of the actual relative distance of the vehicle.

[0112] S202: For each distance condition, determine an expected relative speed of the vehicle in the distance condition, and determine a target acceleration of the vehicle based on the expected relative speed.

[0113] Here, the distance situation includes a first distance situation, a second distance situation, a third distance situation, a fourth distance situation, and a fifth distance situation.

[0114] First, if the actual relative distance of the vehicle is greater than a preset constant and less than a lower limit of the distance interval, the distance condition between the vehicle and the target vehicle is determined to be a first distance condition;

[0115] When 0<d actual <d openLow , that is, in (0, ), within this distance range, the two vehicles are close to each other, and measures need to be taken to increase the distance between the two vehicles to ensure safety. At this time, we further determine the target acceleration based on the actual relative speed of the vehicles, that is, the two vehicles are close to each other, and the distance between the two vehicles needs to be increased, and further distinguish them based on the actual relative distance.

[0116] The target acceleration of the vehicle when the distance condition between the vehicle and the target vehicle is the first distance condition is determined by:

[0117] (1) when it is detected that the actual relative speed is less than the lower limit of the away speed interval, calculating a first difference between the actual relative speed and the lower limit of the away speed interval, and determining a ratio of the first difference to the actual time distance, and determining the ratio of the first difference to the actual time distance as the target acceleration of the vehicle;

[0118] Here, the actual relative speed is less than the lower limit of the speed range (v actual <v openLow ).

[0119] When the actual relative speed is less than the lower limit of the away speed interval, it means that the speed of the vehicle is relatively slow or the speed is not much different from that of the vehicle in front, and it is necessary to slow down to increase the distance between the two vehicles. At this time, we calculate the first difference between the actual relative speed and the lower limit of the away speed interval, and determine the ratio of the first difference to the actual time interval as the target acceleration. Here, in order to decelerate the actual relative speed to the lower limit of the away speed interval within the actual time interval, the vehicle needs to accelerate at a target Target acceleration for deceleration.

[0120] (2) when it is detected that the actual relative speed is greater than or equal to the lower limit of the speed interval and less than or equal to the upper limit of the speed interval, a preset constant is determined as the target acceleration of the vehicle;

[0121] Here, the actual relative speed is within the speed range (v openLow ≤v actual ≤v openHigh ).

[0122] When the actual relative speed is within the speed range, it means that the relative speed of the two vehicles is already within a safe and efficient range, and no acceleration or deceleration is required. At this time, we can set the target acceleration to 0, which means that the vehicle can maintain the current speed, and the preset constant is 0.

[0123] (3) When it is detected that the actual relative speed is greater than the upper limit of the speed interval, a second difference between the actual relative speed and the upper limit of the speed interval is calculated, and a ratio of the second difference to the actual time distance is determined. The ratio of the second difference to the actual time distance is determined as the target acceleration of the vehicle. Here, the actual relative speed of the vehicle is within the speed interval, and the vehicle does not need to accelerate or decelerate, and the vehicle ahead will naturally increase the distance from the vehicle.

[0124] Here, the actual relative speed is greater than the upper limit of the speed interval (v actual >v openHigh ).

[0125] When the actual relative speed is greater than the upper limit of the speed interval, it means that the speed of the vehicle in front is much faster. The vehicle needs to accelerate and accelerate to the expected relative speed interval according to the target acceleration. At this time, we calculate the second difference between the actual relative speed and the upper limit of the speed interval, and determine the ratio of the second difference to the actual time distance as the target acceleration. The acceleration operation here should be to increase the efficiency of following the vehicle.

[0126] The target acceleration of the vehicle in the first distance case is determined by the following formula:

[0127]

[0128] Among them, a target is the target acceleration, vactual is the actual relative speed, v openHigh To be far away from the upper limit of the speed range, v openLow To stay away from the lower limit of the speed range, t gap The actual time interval.

[0129] Formula (1-1) assumes that the actual relative speed is small at this time, that is, the speed of the vehicle is similar to or much faster than the speed of the vehicle in front. The vehicle needs to slow down so that the actual relative speed converges to the expected relative speed range to increase the distance between the two vehicles and ensure safety.

[0130] Formula (1-2), take 0, that is, it is considered that in [v openLow , v openHigh ] Within the interval, the actual relative distance is safe and efficient, and there is no need to accelerate or decelerate. The vehicle ahead will increase the distance from the vehicle, so that the actual relative distance converges to the distance point;

[0131] Formula (1-3) assumes that the actual relative speed is relatively large, that is, the speed of the preceding vehicle is much faster, and the vehicle accelerates, so that the actual relative speed converges to the expected relative speed range to increase the following efficiency.

[0132] Second, if the actual relative distance of the vehicle is greater than or equal to the lower limit of the distance interval, and less than or equal to the upper limit of the distance interval, then the distance situation between the vehicle and the target vehicle is determined to be the second distance situation;

[0133] When d is satisfied openLow ≤d actual ≤d openUp , that is, in That is, the two vehicles are close to each other and need to be separated. Each actual relative distance corresponds to an expected relative speed. Here, the upper limit of the relative speed is recalculated, and the upper limit of the relative speed is the first expected relative speed.

[0134] The target acceleration of the vehicle when the distance condition between the vehicle and the target vehicle is the second distance condition is determined by:

[0135] Calculate a first expected relative speed according to the lower limit of the away speed interval, the second preset penalty speed, the actual relative distance, the upper limit of the away distance interval, and the final expected distance;

[0136] Here, we introduce a dynamically changing upper limit of the relative speed, which is the first expected relative speed. The calculation formula of the first expected relative speed is as follows:

[0137]

[0138] Among them, v openHighNew is the first expected relative velocity, v openLowTo stay away from the lower limit of the speed range, v openUpPunish is the second preset penalty speed, d actual is the actual relative distance, d openUp is the upper limit of the distance interval, d desired is the final expected distance.

[0139] Here, v openUpPunish It is a preset penalty speed, which is used to adjust the degree of reduction of the upper limit of the relative speed when the actual relative distance is close to the upper limit of the distance interval. openHighNew The value range is between [3,5]m / s, according to d actual Dynamically adjust according to changes in

[0140] (1) when it is detected that the actual relative speed is less than the lower limit of the away speed interval, calculating a third difference between the actual relative speed and the lower limit of the away speed interval, and determining a ratio of the third difference to the actual time distance, and determining the ratio of the third difference to the actual time distance as the target acceleration of the vehicle;

[0141] Here, the actual relative speed is less than the lower limit of the speed range (v actual <v openLow ).

[0142] When the actual relative speed is less than the lower limit of the speed interval, it means that the actual relative speed of the vehicle is slow and needs to be accelerated to approach the expected relative speed. At this time, we calculate v actual With v openLow The third difference between the two, and the ratio of it to the actual time interval is taken as the target acceleration a target .

[0143] (2) when it is detected that the actual relative speed is greater than or equal to the lower limit of the speed interval and less than or equal to the first expected relative speed, a preset constant is determined as the target acceleration of the vehicle;

[0144] Here, the actual relative speed is greater than or equal to the lower limit of the speed interval, and less than or equal to the first expected relative speed (v openLow ≤v actual ≤v openHighNew ).

[0145] When the actual relative speed is greater than or equal to the lower limit of the speed interval and less than or equal to the first expected relative speed, it means that the actual relative speed of the vehicle is already within the expected relative speed interval and no acceleration or deceleration is required. At this time, we can set the target acceleration a target Set to 0 to maintain current speed.

[0146] (3) When it is detected that the actual relative speed is greater than the first expected relative speed, a fourth difference between the actual relative speed and the first expected relative speed is calculated, and a ratio of the fourth difference to the actual time distance is determined, and the ratio of the fourth difference to the actual time distance is determined as the target acceleration of the vehicle.

[0147] Here, the actual relative speed is greater than the first expected relative speed (v actual >v openHighNew ).

[0148] When the actual relative speed is greater than the first expected relative speed, it means that the actual relative speed of the vehicle is too fast and it needs to slow down to avoid collision with the vehicle in front or to maintain a safe distance. At this time, we calculate v actual With v openHighNew and compare it with the actual time interval t gap The ratio of is taken as the target acceleration a target However, it should be noted that the deceleration operation here should follow certain deceleration limits to avoid sudden braking and other situations.

[0149] The target acceleration of the vehicle at the second distance is determined by the following formula:

[0150]

[0151] Among them, a target is the target acceleration, v actual is the actual relative speed, v openLow To stay away from the lower limit of the speed range, v openHighNew is the first expected relative speed, t gap The actual time interval.

[0152] Formula (2-1) assumes that the actual relative speed is large, that is, the speed of the preceding vehicle is much faster, and the vehicle accelerates, so that the actual relative speed converges to the expected relative speed range to increase the following efficiency;

[0153] Formula (2-2) takes 0, which means that in [v openLow , v openHighNew ] Within the interval, the actual relative distance is safe and efficient, and there is no need to accelerate or decelerate. The vehicle ahead will increase the distance from the vehicle, so that the actual relative distance converges to the distance point;

[0154] Formula (2-3) assumes that the actual relative speed is relatively small at this time, that is, the speed of this vehicle is similar to or much faster than the speed of the vehicle in front. This vehicle needs to slow down so that the actual relative speed converges to the expected relative speed range to increase the distance between the two vehicles and ensure safety.

[0155] Third, if the actual relative distance of the vehicle is greater than the upper limit of the distance interval and less than or equal to the final expected distance, the distance situation between the vehicle and the target vehicle is determined to be the third distance situation;

[0156] When d is satisfied openUp <d actual ≤d desired , that is, in That is, the two cars are close to each other and need to be separated. Each actual relative distance corresponds to an expected relative speed.

[0157] The target acceleration of the vehicle when the distance condition between the vehicle and the target vehicle is the third distance condition is determined by:

[0158] Calculating a second expected relative speed according to the first preset penalty speed, the actual relative distance, and the final expected distance;

[0159] The second expected relative speed is to gradually increase the distance between the two vehicles while maintaining safety. The calculation formula of the second expected relative speed is as follows:

[0160]

[0161] Among them, v openNew is the second expected relative velocity, v openLowPunish is the first preset penalty speed, d actual is the actual relative distance, d desired is the final expected distance.

[0162] Here, the value of the second desired relative velocity also changes dynamically, ranging from [0,3] m / s. In the given formula, v openNew The calculation of takes into account the difference between the actual relative distance and the final expected distance, and multiplies it by a coefficient related to the first preset penalty speed (here v openLowPunish However, the specific calculation may involve more factors, such as vehicle performance, road conditions, etc.).

[0163] A fifth difference between the actual relative speed and the second expected relative speed is calculated, and a ratio of the fifth difference to the actual time distance is determined, and the ratio of the fifth difference to the actual time distance is determined as the target acceleration of the vehicle.

[0164] Here, the difference between the actual relative speed and the second expected relative speed, i.e., the fifth difference, is calculated, and the difference is divided by the actual time interval to obtain the target acceleration of the vehicle. The actual time interval may represent the time required for the two vehicles to maintain the current speed difference, or a safe time interval determined according to factors such as road conditions and traffic conditions.

[0165] The target acceleration of the vehicle at the third distance is determined by the following formula:

[0166] a target =(v actual -v openNew )) / t gap

[0167] Among them, a target is the target acceleration, v actual is the actual relative speed, v openNew is the second expected relative speed, t gap The actual time interval.

[0168] Based on the above calculation, the target acceleration of the vehicle is directly obtained. This acceleration will guide the vehicle on how to adjust its speed to gradually increase the distance from the target vehicle in front. When the distance between the vehicle and the target vehicle is at the third distance, the target acceleration of the vehicle can be determined by calculating the second expected relative speed and combining the relationship between the actual relative speed and the actual time distance. This process is designed to ensure a safe distance between the two vehicles and avoid potential collision risks.

[0169] Fourth, if the actual relative distance of the vehicle is greater than the final expected distance and less than or equal to the lower limit of the approach distance, then the distance situation between the vehicle and the target vehicle is determined to be the fourth distance situation;

[0170] When d is satisfied desired <d actual ≤d closeLow , that is, in (d desired , ], that is, the two cars are far apart and need to be shortened. Each actual relative distance corresponds to an expected relative speed.

[0171] The target acceleration of the vehicle when the distance condition between the vehicle and the target vehicle is the fourth distance condition is determined by:

[0172] Calculating a third expected relative speed according to the third preset penalty speed, the actual relative distance, and the final expected distance;

[0173] The third expected relative speed refers to the situation where the distance between the two vehicles is greater than the expected distance but has not reached the threshold of being too close. In this case, the system needs to calculate an appropriate acceleration to safely and efficiently shorten the distance between the two vehicles. The calculation formula for the third expected relative speed is as follows:

[0174]

[0175] Among them, v closeNew is the third expected relative velocity, v closeLowPunishis the third preset penalty speed, d actual is the actual relative distance, d desired is the final expected distance.

[0176] Here, the value of the third desired relative speed also changes dynamically, ranging from [-3,0] m / s.

[0177] A sixth difference between the actual relative speed and the third expected relative speed is calculated, and a ratio of the sixth difference to the actual time distance is determined, and the ratio of the sixth difference to the actual time distance is determined as the target acceleration of the vehicle.

[0178] Specifically, after calculating the expected speed, the difference between the actual relative speed and the expected speed is further calculated, and the ratio of this difference to the actual time interval (i.e., the time interval between the two vehicles) is used as the target acceleration of the vehicle. This design ensures that the vehicle approaches the target vehicle with an appropriate acceleration while maintaining a safe distance.

[0179] The target acceleration of the vehicle in the fourth distance case is determined by the following formula:

[0180] a target =(v actual -v closeNew ) / t gap

[0181] Among them, a target is the target acceleration, v actual is the actual relative speed, v closeNew is the third expected relative speed, t gap The actual time interval.

[0182] Fifth, if the actual relative distance of the vehicle is greater than the lower limit of the approach distance, the distance condition between the vehicle and the target vehicle is determined to be the fifth distance condition.

[0183] When d is satisfied closeLow <d actual , that is, in ( +∞), that is, the two cars are far apart and need to be brought closer. Each actual relative distance corresponds to an expected relative speed. Here, the lower limit of the relative speed v is recalculated. closeLowNew .

[0184] The target acceleration of the vehicle when the distance condition between the vehicle and the target vehicle is the fifth distance condition is determined by:

[0185] Calculating a fourth expected relative speed according to the upper limit of the approaching speed interval, the fourth preset penalty speed, the actual relative distance, the lower limit of the approaching distance interval, and the final expected distance;

[0186] Here, we introduce a dynamically changing lower limit of the relative speed, which is the fourth expected relative speed. The calculation formula of the fourth expected speed is as follows:

[0187]

[0188] Among them, v closeLowNew is the fourth expected relative velocity, v closeHigh is close to the upper limit of the speed range, v closeUpPunish The fourth preset penalty speed, d actual is the actual relative distance, d closeLow is close to the lower limit of the distance interval, d desired is the final expected distance.

[0189] Here, v closeLowNew The value of the fourth expected relative velocity changes dynamically, ranging from (-∞, -3) m / s.

[0190] (1) when it is detected that the actual relative speed is less than the fourth expected relative speed, calculating a seventh difference between the actual relative speed and the fourth expected relative speed, determining a ratio of the seventh difference to the actual time distance, and determining the ratio of the seventh difference to the actual time distance as a target acceleration of the vehicle;

[0191] Here, the actual relative speed is less than the fourth desired relative speed (v actual <v closeLowNew ).

[0192] When the actual relative speed is less than the fourth expected relative speed, the difference between the two is calculated, and the ratio of this difference to the actual time interval (the time interval between the two vehicles) is used as the target acceleration of the vehicle. This ensures that the vehicle does not approach the front vehicle too quickly, thereby maintaining a safe distance.

[0193] (2) when it is detected that the actual relative speed is greater than or equal to the fourth expected relative speed and less than or equal to the upper limit of the approach speed interval, determining a preset constant as the target acceleration of the vehicle;

[0194] Here, the actual relative speed is greater than or equal to the fourth expected relative speed and less than or equal to the upper limit of the approach speed interval (v closeLowNew ≤v actual ≤v closeHigh ).

[0195] When the actual relative speed is greater than or equal to the fourth expected relative speed and less than or equal to the upper limit of the approaching speed range, it means that the actual relative speed of the vehicle is already within the expected relative speed range and no acceleration or deceleration operation is required. At this time, we can set the target acceleration a target Set to 0 to maintain current speed.

[0196] (3) When it is detected that the actual relative speed is greater than the upper limit of the closing speed interval, an eighth difference between the actual relative speed and the upper limit of the closing speed interval is calculated, and a ratio of the eighth difference to the actual time distance is determined, and the ratio of the eighth difference to the actual time distance is determined as the target acceleration of the vehicle.

[0197] Here, the actual relative speed is greater than the upper limit of the approach speed range (v actual >v closeHigh ).

[0198] When the actual relative speed is greater than the upper limit of the approaching speed interval, the difference between the actual relative speed and the upper limit is calculated, and the ratio of this difference to the actual time distance is used as the target acceleration of the vehicle, which can ensure that the vehicle approaches the vehicle in front with an appropriate acceleration.

[0199] The target acceleration of the vehicle in the fifth distance case is determined by the following formula:

[0200]

[0201] Formula (3-1) assumes that the absolute value of the actual relative speed is relatively large (high for the own vehicle and low for the vehicle ahead), and the own vehicle decelerates, so that the actual relative speed converges to the expected relative speed range while ensuring safety.

[0202] Formula (3-2) takes 0, which means that in [v closeLowNew , v closeHigh ] interval, the actual relative distance is safe and efficient, and there is no need to accelerate or decelerate. The front vehicle will close the distance to the vehicle, making the actual relative distance close to the distance point d closeLow convergence;

[0203] Formula (3-3) assumes that the absolute value of the actual relative speed is small (the speed of this vehicle is similar to that of the vehicle in front) or the actual relative speed is large (the vehicle in front is high and this vehicle is low). This vehicle needs to accelerate to approach the vehicle in front in order to increase the following efficiency and make the actual relative speed converge to the expected relative speed range.

[0204] The automatic driving vehicle control method and vehicle provided in the embodiment of the present application obtain the actual speed and actual headway of the vehicle, the actual relative speed between the vehicle and the target vehicle located in front of the vehicle, and the actual relative distance between the vehicle and the target vehicle; determine the basic expected distance according to the actual speed and actual headway of the vehicle; determine the final expected distance according to the basic expected distance, the curvature compensation coefficient, and the slope compensation coefficient; determine the critical value of the preset distance interval according to the final expected distance and the preset speed interval; determine the interval situation corresponding to the actual relative distance, and determine the expected relative speed according to the interval situation and the critical value of the preset speed interval; determine the target acceleration of the vehicle according to the actual relative speed, the expected relative speed, and the actual headway, and control the vehicle to travel at the target acceleration. Through this application, the relative distance between the vehicle and the target vehicle is automatically adjusted according to the target acceleration, which improves the adaptability and intelligence of the cruise control and improves the driving efficiency.

[0205] After determining the target acceleration, the vehicle control system will immediately take action to keep the actual acceleration of the vehicle consistent with the target acceleration by adjusting the engine output power, the braking force of the braking system, and the angle of the steering system, etc. In this way, the vehicle can follow the target vehicle at the optimal speed and distance, maintaining a safe distance and improving driving efficiency.

[0206] This application takes into account road conditions and adaptively adjusts the desired distance from the vehicle in front; divides the following distance into two intervals, "far" and "close", and performs adaptive control based on distance segments; improves the adaptability and intelligence of cruise control; improves ride comfort and safety; and optimizes fuel / electricity economy and traffic efficiency.

[0207] The present invention can dynamically adjust the acceleration planning according to the real-time road conditions and vehicle status. By considering the path curvature and slope to appropriately increase the following distance, and dividing different relative distances and relative speeds, the calculated acceleration instructions are more accurate and can adapt to different driving modes and environments. Under the premise of ensuring safety, the driving efficiency is improved as much as possible.

[0208] An embodiment of the present application also provides a vehicle, which includes the autonomous driving vehicle control method as described above.

[0209] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0210] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0211] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0212] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0213] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application can essentially be embodied in the form of a software product, or in other words, the part that contributes to the prior art or the part of the technical solution. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0214] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the above-mentioned embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-mentioned embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for controlling an automatic driving vehicle, characterized in that: include: Obtaining the actual speed and actual time distance of the vehicle, the actual relative speed between the vehicle and the target vehicle in front of the vehicle, and the actual relative distance between the vehicle and the target vehicle; Determine the basic expected distance according to the actual speed and actual time distance of the vehicle; Determining a final expected distance according to the basic expected distance, the curvature compensation coefficient and the slope compensation coefficient; Determining a threshold value of a preset distance interval according to the final expected distance and the preset speed interval, each preset speed interval corresponding to each preset distance interval; Determine the interval situation corresponding to the actual relative distance, and determine the expected relative speed according to the interval situation and the threshold value of the preset speed interval, where different interval situations correspond to different expected relative speeds; A target acceleration of the vehicle is determined according to the actual relative speed, the expected relative speed, and the actual time interval, and the vehicle is controlled to travel at the target acceleration.

2. The method according to claim 1, characterized in that The preset distance interval includes a far distance interval and a near distance interval, the preset speed interval includes a far speed interval and a near speed interval, the far distance interval corresponds to the far speed interval, and the near distance interval corresponds to the near speed interval, The critical value of the preset distance interval of the vehicle is determined in the following manner: Determine a comparison result of the actual relative distance and the final expected distance; According to the comparison result, determining whether the vehicle is in the distance interval; If the vehicle is in the away distance interval, an upper limit of the away distance interval is determined according to a lower limit of the away speed interval, a first preset penalty speed and the final expected distance, and a lower limit of the away distance interval is determined according to the upper limit of the away distance interval, the upper limit of the away speed interval, the lower limit of the away speed interval, a second preset penalty speed and the final expected distance; If the vehicle is not in the away distance interval, the lower limit value of the approaching distance interval is determined according to the upper limit value of the approaching speed interval, the third preset penalty speed and the final expected distance, and the upper limit value of the approaching distance interval is determined according to the lower limit value of the approaching distance interval, the lower limit value of the approaching speed interval, the upper limit value of the approaching speed interval, the fourth preset penalty speed and the final expected distance.

3. The method according to claim 2, characterized in that The target acceleration of the vehicle is determined by: Determining the distance between the vehicle and the target vehicle according to the distance range of the actual relative distance of the vehicle; For each distance condition, an expected relative speed of the vehicle in the distance condition is determined, and a target acceleration of the vehicle is determined based on the expected relative speed.

4. The method according to claim 3, characterized in that: The distance conditions include a first distance condition, a second distance condition, a third distance condition, a fourth distance condition and a fifth distance condition, Wherein, determining the distance between the vehicle and the target vehicle according to the distance range of the actual relative distance of the vehicle includes: If the actual relative distance of the vehicle is greater than the preset constant and less than the lower limit of the distance interval, the distance condition between the vehicle and the target vehicle is determined to be a first distance condition; If the actual relative distance of the vehicle is greater than or equal to the lower limit of the distance interval, and less than or equal to the upper limit of the distance interval, then the distance situation between the vehicle and the target vehicle is determined to be the second distance situation; If the actual relative distance of the vehicle is greater than the upper limit of the distance interval and less than or equal to the final expected distance, then the distance situation between the vehicle and the target vehicle is determined to be a third distance situation; If the actual relative distance of the vehicle is greater than the final expected distance and less than or equal to the approach distance lower limit, then determining that the distance situation between the vehicle and the target vehicle is a fourth distance situation; If the actual relative distance of the vehicle is greater than the lower limit of the approach distance, it is determined that the distance condition between the vehicle and the target vehicle is the fifth distance condition.

5. The method according to claim 4, characterized in that The target acceleration of the vehicle when the distance condition between the vehicle and the target vehicle is the first distance condition is determined by: When it is detected that the actual relative speed is less than the lower limit of the speed interval away from the vehicle, a first difference between the actual relative speed and the lower limit of the speed interval away from the vehicle is calculated, and a ratio of the first difference to the actual time interval is determined, and the ratio of the first difference to the actual time interval is determined as a target acceleration of the vehicle; When it is detected that the actual relative speed is greater than or equal to the lower limit of the away speed interval and less than or equal to the upper limit of the away speed interval, a preset constant is determined as the target acceleration of the vehicle; When it is detected that the actual relative speed is greater than the upper limit of the speed interval away from the vehicle, a second difference between the actual relative speed and the upper limit of the speed interval away from the vehicle is calculated, and a ratio of the second difference to the actual time distance is determined, and the ratio of the second difference to the actual time distance is determined as the target acceleration of the vehicle.

6. The method according to claim 4, characterized in that The target acceleration of the vehicle when the distance condition between the vehicle and the target vehicle is the second distance condition is determined by: Calculate a first expected relative speed according to the lower limit of the away speed interval, the second preset penalty speed, the actual relative distance, the upper limit of the away distance interval, and the final expected distance; When it is detected that the actual relative speed is less than the lower limit of the speed interval away from the vehicle, a third difference between the actual relative speed and the lower limit of the speed interval away from the vehicle is calculated, and a ratio of the third difference to the actual time distance is determined, and the ratio of the third difference to the actual time distance is determined as the target acceleration of the vehicle; When it is detected that the actual relative speed is greater than or equal to the lower limit of the away speed interval and less than or equal to the first expected relative speed, a preset constant is determined as the target acceleration of the vehicle; When it is detected that the actual relative speed is greater than the first expected relative speed, a fourth difference between the actual relative speed and the first expected relative speed is calculated, and a ratio of the fourth difference to the actual time distance is determined, and the ratio of the fourth difference to the actual time distance is determined as the target acceleration of the vehicle.

7. The method according to claim 4, characterized in that The target acceleration of the vehicle when the distance condition between the vehicle and the target vehicle is the third distance condition is determined by: Calculating a second expected relative speed according to the first preset penalty speed, the actual relative distance and the final expected distance; A fifth difference between the actual relative speed and the second expected relative speed is calculated, and a ratio of the fifth difference to the actual time distance is determined, and the ratio of the fifth difference to the actual time distance is determined as a target acceleration of the vehicle.

8. The method according to claim 4, characterized in that The target acceleration of the vehicle when the distance condition between the vehicle and the target vehicle is the fourth distance condition is determined by: Calculating a third expected relative speed according to the third preset penalty speed, the actual relative distance and the final expected distance; A sixth difference between the actual relative speed and the third expected relative speed is calculated, and a ratio of the sixth difference to the actual time distance is determined, and the ratio of the sixth difference to the actual time distance is determined as a target acceleration of the vehicle.

9. The method according to claim 4, characterized in that The target acceleration of the vehicle when the distance condition between the vehicle and the target vehicle is the fifth distance condition is determined by: Calculating a fourth expected relative speed according to the upper limit of the approaching speed interval, the fourth preset penalty speed, the actual relative distance, the lower limit of the approaching distance interval, and the final expected distance; When it is detected that the actual relative speed is less than the fourth expected relative speed, a seventh difference between the actual relative speed and the fourth expected relative speed is calculated, and a ratio of the seventh difference to the actual time distance is determined, and the ratio of the seventh difference to the actual time distance is determined as a target acceleration of the vehicle; When it is detected that the actual relative speed is greater than or equal to the fourth expected relative speed and less than or equal to the upper limit of the approaching speed interval, a preset constant is determined as the target acceleration of the vehicle; When it is detected that the actual relative speed is greater than the upper limit of the approaching speed interval, an eighth difference between the actual relative speed and the upper limit of the approaching speed interval is calculated, and a ratio of the eighth difference to the actual time distance is determined, and the ratio of the eighth difference to the actual time distance is determined as the target acceleration of the vehicle.

10. A vehicle, characterized in that: The vehicle includes an autonomous driving vehicle control method as described in any one of claims 1-9.

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