Automatic vehicle speed limiting device and method

Abstract

The application discloses an automatic driving vehicle speed limiting device and method, and relates to the technical field of automatic driving. The device comprises a brake system, a driving system, a control system and a vehicle controller. The brake system comprises a brake controller and a brake execution mechanism, the brake controller can control the brake execution mechanism to realize vehicle braking. The driving system comprises a driving controller and a driving motor, the driving controller can control the driving motor to realize vehicle driving and braking. The control system is used for determining vehicle speed limiting demand according to road conditions and road speed limit signs. The vehicle controller is used for determining a vehicle speed limiting target value according to vehicle gear, vehicle state and speed limiting demand, and controlling the driving system to perform vehicle acceleration control and speed control or controlling the brake system to brake according to the speed limiting target value, so as to realize vehicle speed limiting. The automatic driving vehicle speed limiting device according to the embodiment of the application can realize vehicle speed limiting demand under different working conditions.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automatic driving, in particular to an automatic driving vehicle speed limiting device and method. BACKGROUND

[0002] At present, the speed limiting of the automatic driving vehicle is mainly motor automatic speed limiting, however, the motor automatic speed limiting can only calibrate a fixed forward speed limiting point, cannot flexibly limit the speed according to different situations, cannot respond to the speed limiting demand of each working condition in real time, and when downhill or motor failure occurs, the vehicle speed loss occurs. SUMMARY

[0003] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application provides an automatic driving vehicle speed limiting device and method, which can limit the speed of the automatic driving vehicle according to different situations.

[0004] In one aspect, the automatic driving vehicle speed limiting device according to the embodiment of the present application comprises:

[0005] A brake system comprising a brake controller and a brake actuator, wherein the brake controller can control the brake actuator to realize vehicle braking;

[0006] A drive system comprising a drive controller and a drive motor, wherein the drive controller can control the drive motor to realize vehicle driving and braking;

[0007] A control system for determining the speed limiting demand of the vehicle according to the road condition and the speed limiting sign of the road;

[0008] A vehicle controller for determining the speed limiting target value of the vehicle according to the vehicle gear, the vehicle state and the speed limiting demand, and controlling the drive system to realize vehicle acceleration control and speed control, or controlling the brake system to realize braking, so as to realize the speed limiting of the vehicle according to the speed limiting target value.

[0009] The automatic driving vehicle speed limiting device according to the embodiment of the present application, wherein the control system comprises:

[0010] A camera for identifying the speed limiting sign of the road;

[0011] A radar sensor for identifying the obstacle around the vehicle, the distance between the vehicle and the front vehicle, and the speed of the front vehicle;

[0012] A processor for calculating the speed limiting demand of the vehicle according to the identification results of the camera and the radar sensor.

[0013] In another aspect, the automatic driving vehicle speed limiting method according to the embodiment of the present application comprises the following steps:

[0014] The control system determines a speed limit demand of the vehicle according to road conditions and a speed limit sign of the road;

[0015] The vehicle controller determines a speed limit target value of the vehicle according to a gear of the vehicle, a state of the vehicle, and the speed limit demand;

[0016] According to the speed limit target value, the vehicle controller controls the driving system to perform vehicle acceleration control and vehicle speed control, or controls the brake system to brake, so as to achieve redundant control of the speed limit of the vehicle.

[0017] According to the automatic driving vehicle speed limit method, the control system determines a speed limit demand of the vehicle according to road conditions and a speed limit sign of the road, including:

[0018] The speed limit sign of the road is recognized by a camera;

[0019] Obstacles around the vehicle, a distance between the vehicle and a preceding vehicle, and a speed of the preceding vehicle are recognized by a radar sensor;

[0020] The speed limit demand of the vehicle is calculated according to the recognition results of the camera and the radar sensor.

[0021] According to the automatic driving vehicle speed limit method, the vehicle controller determines a speed limit target value of the vehicle according to a gear of the vehicle, a state of the vehicle, and the speed limit demand, including:

[0022] The vehicle controller determines a first speed limit value of the vehicle according to the gear of the vehicle;

[0023] The vehicle controller determines a second speed limit value of the vehicle according to the state of the vehicle;

[0024] The vehicle controller determines a third speed limit value of the vehicle according to the speed limit demand;

[0025] The minimum value among the first speed limit value, the second speed limit value, and the third speed limit value is taken as the speed limit target value of the vehicle.

[0026] According to the automatic driving vehicle speed limit method, according to the speed limit target value, the vehicle controller controls the driving system to perform vehicle acceleration control and vehicle speed control, or controls the brake system to brake, so as to achieve the speed limit of the vehicle, including:

[0027] According to the speed limit target value, a speed limit difference value is determined; the speed limit difference value is used to represent a difference between the speed limit target value and a current speed of the vehicle;

[0028] determining a target acceleration coefficient according to the speed limit difference value, the target acceleration coefficient decreasing with the decrease of the speed limit difference value, and the target acceleration coefficient being zero when the speed limit difference value decreases to zero;

[0029] obtaining a current acceleration of the vehicle, and taking a product of the target acceleration coefficient and the current acceleration as a target acceleration of the vehicle;

[0030] obtaining a first target torque demand of the vehicle through PI regulation by taking a current torque demand of the vehicle as a P value of the PI regulation, taking a difference between the target acceleration and the current acceleration as an acceleration difference value, and taking the acceleration difference value as an I value of the PI regulation, and setting the I value of the PI regulation to zero when the current acceleration of the vehicle is less than the target acceleration;

[0031] controlling the vehicle according to the first target torque demand, so that an acceleration of the vehicle when the speed of the vehicle reaches the speed limit target value is not greater than the target acceleration.

[0032] According to the vehicle speed limiting method of the automatic driving vehicle, the vehicle controller controls the driving system to perform vehicle acceleration control and speed control, or controls the brake system to brake, so as to limit the speed of the vehicle, and the method comprises the following steps:

[0033] obtaining a second target torque demand of the vehicle through PI regulation by taking a current torque demand of the vehicle as a P value of the PI regulation, and taking the speed limit difference value as an I value of the PI regulation when the speed limit difference value is less than zero and greater than a first preset value, wherein the first preset value is less than zero;

[0034] controlling the speed of the vehicle to reach the speed limit target value according to the second target torque demand.

[0035] According to the vehicle speed limiting method of the automatic driving vehicle, the vehicle controller controls the driving system to perform vehicle acceleration control and speed control, or controls the brake system to brake, so as to limit the speed of the vehicle, and the method comprises the following steps:

[0036] controlling the brake system to linearly output a brake force to brake the vehicle when the speed limit difference value is less than the first preset value and greater than a second preset value, the brake force decreasing with the decrease of an absolute value of the speed limit difference value, so that the speed of the vehicle reaches the speed limit target value, wherein the second preset value is less than the first preset value.

[0037] According to the automatic driving vehicle speed limiting method, the vehicle controller controls the driving system to perform vehicle acceleration control and vehicle speed control or controls the brake system to brake according to the speed limiting target value, so as to realize speed limiting of the vehicle.

[0038] When the speed limiting difference value is less than the second preset value, the brake system outputs the maximum brake force to brake until the speed limiting difference value reaches a third preset value, at this time, the brake force output by the brake system is linearly decreased to zero, so that the speed of the vehicle reaches the speed limiting target value, wherein the third preset value is greater than zero.

[0039] According to the automatic driving vehicle speed limiting device and method, as long as any one of the brake system and the driving system works normally, the speed limiting of the vehicle can be realized, the speed limiting demand of the vehicle under different working conditions can be realized, and the driving safety can be ensured.

[0040] Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following and / or can be learned by practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0041] The above and / or additional aspects and advantages of the application will become apparent and be readily understood by considering the following detailed description, from which the singular aspects become apparent.

[0042] Figure 1 The structure schematic diagram of the automatic driving vehicle speed limiting device of the embodiment of the application is shown in the figure.

[0043] Figure 2 The step flow chart of the automatic driving vehicle speed limiting method of the embodiment of the application is shown in the figure.

[0044] Reference signs:

[0045] The brake system 100, the driving system 200, the control system 300, and the vehicle controller 400. DETAILED DESCRIPTION

[0046] The specific embodiments of the present application will be described in detail in this part, the preferred embodiments of the present application are shown in the drawings, the role of the drawings is to supplement the description of the text part of the description with graphics, so that people can intuitively and visually understand each technical feature and the overall technical scheme of the present application, but it cannot be understood as a limitation on the protection scope of the present application.

[0047] In the description of the present application, one or more is the meaning of one or more, the meaning of multiple is more than two, greater than, less than, more than, etc. is understood as not including the number, above, below, within, etc. is understood as including the number. If it is described as first, second, it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or implicitly indicating the sequence of indicated technical features.

[0048] In the description of the present application, unless otherwise explicitly limited, the words such as setting, installing, connecting, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical scheme.

[0049] On the one hand, as Figure 1 shown, the present application proposes a kind of automatic driving vehicle speed limiting device, including brake system 100, drive system 200, control system 300 and whole vehicle controller 400;Brake system 100 includes brake controller and brake actuating mechanism, brake controller can control brake actuating mechanism realizes vehicle brake;Drive system 200 includes drive controller and drive motor, drive controller can control drive motor realizes the drive and brake of vehicle;Control system 300 is used to determine the speed limit demand of vehicle according to road condition and the speed limit sign of road;Whole vehicle controller 400 is used to determine the speed limit target value of vehicle according to vehicle gear, vehicle state and speed limit demand, and according to the speed limit target value, control drive system carries out vehicle acceleration control and vehicle speed control, when drive system cannot realize speed limit control, control brake system carries out brake speed limit, realizes the redundancy control of vehicle speed limit.

[0050] Specifically, control system 300 is used for the control of vehicle automatic driving, control system 300 includes camera, radar sensor and processor, control system 300 can identify the speed limit sign of road through camera, can identify the obstacle around vehicle, identify the distance from front vehicle, the vehicle speed of front vehicle, etc. through radar sensor (including millimeter wave radar sensor and laser radar sensor), calculate the speed limit requirement of keeping safe distance from front vehicle;The processor obtains the speed limit demand of vehicle by comprehensive calculation, and sends to whole vehicle controller 400.

[0051] Whole vehicle controller 400 can determine the speed limit target value of vehicle according to the following several aspects:

[0052] (1) The speed limit requirement of the vehicle gear; for example, the speed limit of the forward gear is 80km / h, and the speed limit of the reverse gear is 15km / h, and the specific speed limit of different gears can be adjusted according to actual needs;

[0053] (2) The speed limit requirement of the vehicle state; for example, when the vehicle is in a secondary fault state, the speed limit is 40km / h or other values; when the vehicle is in a crawling mode, the speed limit is 5km / h or other values; different speed limit values are set in advance according to different states that the vehicle may have;

[0054] (3) The speed limit requirement calculated by the control system 300 according to the road condition and the speed limit sign of the road.

[0055] The vehicle controller 400 selects the speed limit target value with the minimum vehicle speed from the speed limit requirements determined in the above aspects as the speed limit target value, compares the speed limit target value with the current vehicle speed, and controls the speed limit of the vehicle through the acceleration control and torque speed limit of the driving system 200 and the brake force speed limit of the brake system 100 in a redundant manner to ensure the safety of the vehicle.

[0056] The automatic driving vehicle speed limiting device according to the embodiment of the application can realize the speed limit of the vehicle as long as any one of the brake system 100 and the driving system 200 works normally, and ensures the safety of driving; moreover, the vehicle controller 400 can automatically detect the vehicle speed and the vehicle state, determine the speed limit requirement of the current vehicle, and control the driving motor of the driving system 200 to perform torque speed limit, and when the torque speed limit cannot limit the vehicle speed, the vehicle controller 400 controls the brake system 100 to perform brake speed limit, thereby realizing the speed limit requirement of the vehicle in different working conditions.

[0057] On the other hand, as shown in Figure 2 illustrated, based on the above automatic driving vehicle speed limiting device, the application further provides an automatic driving vehicle speed limiting method, which comprises the following steps:

[0058] Step S100: The control system 300 determines the speed limit requirement of the vehicle according to the road condition and the speed limit sign of the road;

[0059] Step S200: The vehicle controller 400 determines the speed limit target value of the vehicle according to the vehicle gear, the vehicle state, and the speed limit requirement;

[0060] Step S300: According to the speed limit target value, the vehicle controller 400 controls the driving system 200 to perform vehicle acceleration control and vehicle speed control, or controls the brake system 100 to brake, thereby realizing the speed limit of the vehicle.

[0061] Further, in some embodiments of the present application, the step S100 is specifically: the control system 300 identifies the speed limit sign of the road through the camera, identifies the obstacles around the vehicle, the distance to the front vehicle, the speed of the front vehicle, etc. through the radar sensor (including the millimeter wave radar sensor and the laser radar sensor), and finally calculates the speed limit demand of the vehicle through the identification results of the camera and the radar sensor.

[0062] Further, in some embodiments of the present application, the step S200 specifically includes the following four steps:

[0063] Step S210: The first speed limit value of the vehicle is determined by the vehicle controller 400 according to the gear of the vehicle; for example, when the vehicle is in the forward gear, the first speed limit value can be set to 80km / h or other values, and when the vehicle is in the reverse gear, the first speed limit value can be set to 15km / h or other values. According to different vehicle gears, the corresponding first speed limit value is set;

[0064] Step S220: The second speed limit value of the vehicle is determined by the vehicle controller 400 according to the state of the vehicle; for example, when the vehicle is in the second fault state, the second speed limit value can be set to 40km / h or other values; when the vehicle is in the crawling mode, the second speed limit value can be set to 5km / h or other values; different second speed limit values are set according to different possible states of the vehicle in advance;

[0065] Step S230: The third speed limit value of the vehicle is determined by the vehicle controller 400 according to the speed limit demand;

[0066] Step S240: The minimum value of the first speed limit value, the second speed limit value and the third speed limit value is taken as the speed limit target value of the vehicle.

[0067] Further, in some embodiments of the present application, the step S300 specifically includes the following steps:

[0068] Step S310: The speed limit difference value is determined according to the speed limit target value; the speed limit difference value is used to represent the difference between the speed limit target value and the current speed of the vehicle;

[0069] Step S320: When the speed limit difference value is greater than zero, the target acceleration coefficient is determined according to the speed limit difference value; the target acceleration coefficient decreases with the decrease of the speed limit difference value, and when the speed limit difference value decreases to zero, the target acceleration coefficient is zero;

[0070] Step S330: The current acceleration of the vehicle is obtained, and the product of the acceleration and the target acceleration coefficient is taken as the target acceleration of the vehicle;

[0071] Step S340: taking the current torque demand of the vehicle as a P value of PI regulation, taking the difference between the target acceleration and the current acceleration as an acceleration difference value, and taking the acceleration difference value as an I value of PI regulation, obtaining a first target torque demand of the vehicle through PI regulation; when the current vehicle acceleration is less than the target acceleration, setting the I value of PI regulation to zero;

[0072] Step S350: controlling the acceleration of the vehicle according to the first target torque demand, so that the acceleration of the vehicle when the speed of the vehicle reaches the speed limit target value is not greater than the target acceleration.

[0073] Specifically, after the vehicle controller 400 obtains the speed limit target value, first, the difference between the speed limit target value and the current speed of the vehicle, i.e., the speed limit difference ΔV, is calculated; when the speed limit difference ΔV>0, the speed limit target value is greater than the current speed of the vehicle at this time, and assuming that the speed limit difference ΔV is 5km / h at this time, the target acceleration coefficient Aα that makes the speed limit difference ΔV decrease from 5km / h to 0 is set; the vehicle controller 400 can read the target acceleration coefficient Aα according to the speed limit difference ΔV, and when the speed limit difference ΔV is smaller, the target acceleration coefficient Aα is smaller, and when the speed limit difference ΔV is zero, the target acceleration coefficient Aα is also zero. Subsequently, the vehicle controller 400 calculates the current acceleration α of the vehicle according to the current speed of the vehicle and the speed of the vehicle at the last time, and takes the product of the acceleration α and the target acceleration coefficient Aα as the target acceleration α limit of the vehicle; the vehicle controller 400 takes the current torque demand of the vehicle as a proportional regulation P value of PI regulation, takes the acceleration difference Δα=α limit -α as an integral regulation I value of PI regulation, obtains a first target torque demand of the vehicle through PI regulation, and controls the acceleration of the vehicle to approach the target acceleration according to the first target torque demand, so that the speed of the vehicle reaches the speed limit target value, and the speed limit of the vehicle is realized.

[0074] Further, in some embodiments of the present application, the above-mentioned step S300 further includes the following steps:

[0075] Step S360: when the speed limit difference is less than zero and greater than a first preset value, taking the current torque demand of the vehicle as a P value of PI regulation, and taking the speed limit difference as an I value of PI regulation, obtaining a second target torque demand of the vehicle through PI regulation; wherein the first preset value is less than zero;

[0076] Step S370: controlling the speed of the vehicle to reach the speed limit target value according to the second target torque demand.

[0077] Specifically, assuming that the first preset value is -2 km / h (other values less than 0 can also be used), when -2 km / h < ΔV < 0, the current vehicle speed is greater than the speed limit target value, the vehicle enters the speed limit control phase, the current torque demand of the vehicle is input as the P value of the PI regulation, and the speed limit difference ΔV is input as the I value of the PI regulation, the second target torque demand of the vehicle is obtained through PI regulation, so that the speed of the vehicle is controlled to reach the speed limit target value according to the second target torque demand, and the speed limit of the vehicle is realized.

[0078] Further, in some embodiments of the present application, the step S300 further includes the following steps:

[0079] Step S380: When the speed limit difference is less than the first preset value and greater than a second preset value, the vehicle controller 400 controls the brake system 100 to linearly output brake force, brakes the vehicle, and the brake force decreases with the decrease of the absolute value of the speed limit difference, so that the speed of the vehicle reaches the speed limit target value; wherein the second preset value is less than the first preset value.

[0080] Specifically, assuming that the second preset value is -5 km / h (other values can also be used), when -5 km / h < ΔV < -2 km / h, the vehicle controller 400 controls the brake system 100 to linearly output brake force, the greater the absolute value of the speed limit difference ΔV, the greater the brake force output by the brake system 100, and as the absolute value of the speed limit difference ΔV gradually decreases, the brake force output by the brake system 100 also gradually decreases, and finally reaches 0, so that the speed of the vehicle reaches the speed limit target value, and the speed limit of the vehicle is completed.

[0081] Further, in some embodiments of the present application, the step S300 further includes the following steps:

[0082] Step S390: When the speed limit difference is less than the second preset value, the brake system 100 outputs the maximum brake force to brake until the speed limit difference reaches a third preset value, at which time the brake force output by the brake system 100 linearly decreases to zero, so that the speed of the vehicle reaches the speed limit target value.

[0083] Specifically, assuming that the third preset value is 1 km / h (other values can also be used), when the speed limit difference ΔV < -5 km / h, the brake force output by the brake system 100 reaches the maximum, so that the vehicle is decelerated, at this time the speed limit difference ΔV gradually increases, and the brake force output by the brake system 100 remains unchanged; when the speed limit difference ΔV increases to 1 km / h, the brake force output by the brake system 100 linearly decreases to avoid sudden change of the brake force and cause the vehicle to shake, and finally the speed of the vehicle reaches the speed limit target value, and the speed limit of the vehicle is completed.

[0084] According to the automatic driving vehicle speed limiting method, the vehicle controller 400 automatically detects the vehicle speed and the vehicle state, determines the current vehicle speed limiting demand, and controls the driving motor of the driving system 200 to perform acceleration control and torque speed limiting. When the driving system 200 cannot limit the vehicle speed, the vehicle controller 400 controls the brake system 100 to perform brake speed limiting, thereby realizing the vehicle speed limiting demand in different working conditions. Meanwhile, the speed limiting processes of the driving system 200 and the brake system 100 are controlled in stages, including three-stage control of vehicle acceleration limitation and vehicle speed limitation through torque control of the driving system 200, and vehicle speed limitation through brake force output of the brake system 100. First, the vehicle acceleration is controlled, and then the vehicle speed is controlled. During the acceleration control, the vehicle acceleration is reduced as much as possible, and the vehicle torque is adjusted to approach the demand torque for maintaining the vehicle speed limitation. During the vehicle speed control, the vehicle driving torque is fine-tuned to realize the vehicle speed limitation. The shock caused by torque adjustment during the vehicle speed limitation is reduced, and the excessive adjustment of the vehicle speed is reduced. In addition, the driving system 200 and the brake system 100 are controlled in stages. When the torque speed limiting cannot meet the speed limiting requirement, the brake system 100 is controlled to perform brake force speed limiting, thereby ensuring the safety of the vehicle speed limitation.

[0085] The above describes the embodiments of the present application in detail in combination with the drawings, but the present application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the purpose of the present application.

Claims

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The application relates to a vehicle speed limiting method and system. The application relates to a vehicle speed limiting method and system. The application relates to a vehicle speed limiting method and system. The application relates to a vehicle speed limiting When the speed limit difference value is less than the second preset value, the brake system outputs maximum brake force for braking until the speed limit difference value reaches a third preset value, at which time the brake force output by the brake system linearly decreases to zero, so that the speed of the vehicle reaches the speed limit target value; the third preset value is greater than zero; The control system comprises: a camera for identifying a speed limit sign of a road; a radar sensor for identifying an obstacle around the vehicle, a distance between the vehicle and a preceding vehicle, and a speed of the preceding vehicle; a processor for calculating a speed limit demand of the vehicle according to the identification results of the camera and the radar sensor.

2. A method for limiting speed of an autonomous vehicle, the method comprising: The method comprises the following steps: The control system determines a speed limit demand of the vehicle according to a road condition and a speed limit sign of the road; The vehicle control unit determines a speed limit target value of the vehicle according to a gear position of the vehicle, a state of the vehicle, and the speed limit demand; According to the speed limit target value, the vehicle control unit controls a driving system to perform vehicle acceleration control and vehicle speed control, or controls a brake system to brake, so as to limit the speed of the vehicle, specifically comprising: According to the speed limit target value, a speed limit difference value is determined; the speed limit difference value represents a difference between the speed limit target value and a current speed of the vehicle; When the speed limit difference value is greater than zero, a target acceleration coefficient is determined according to the speed limit difference value; the target acceleration coefficient decreases with the decrease of the speed limit difference value, and the target acceleration coefficient is zero when the speed limit difference value decreases to zero; A current acceleration of the vehicle is obtained, and a product of the acceleration and the target acceleration coefficient is taken as a target acceleration of the vehicle; A current torque demand of the vehicle is taken as a P value of PI adjustment, a difference between the target acceleration and the current acceleration of the vehicle is taken as an acceleration difference value, and the acceleration difference value is taken as an I value of PI adjustment, so as to obtain a first target torque demand of the vehicle through PI adjustment; when the current acceleration of the vehicle is less than the target acceleration, the I value of PI adjustment is set to zero; According to the first target torque demand, acceleration control is performed on the vehicle, so that an acceleration of the vehicle when the speed of the vehicle reaches the speed limit target value is not greater than the target acceleration; When the speed limit difference value is less than zero and greater than a first preset value, a current torque demand of the vehicle is taken as a P value of PI adjustment, and the speed limit difference value is taken as an I value of PI adjustment, so as to obtain a second target torque demand of the vehicle through PI adjustment; the first preset value is less than zero; According to the second target torque demand, the speed of the vehicle is controlled to reach the speed limit target value; When the speed limit difference value is less than the first preset value and greater than a second preset value, the vehicle control unit controls the brake system to linearly output brake force for braking, the brake force decreases with the decrease of an absolute value of the speed limit difference value, so that the speed of the vehicle reaches the speed limit target value; the second preset value is less than the first preset value. When the speed limit difference is less than the second preset value, the brake system outputs a maximum brake force for braking until the speed limit difference reaches a third preset value, at which time the brake force output by the brake system linearly decreases to zero, causing the speed of the vehicle to reach the speed limit target value; wherein the third preset value is greater than zero; The control system determines the speed limit requirement of the vehicle according to the road condition and the speed limit sign of the road, including: identifying the speed limit sign of the road through a camera; identifying the obstacles around the vehicle, the distance between the vehicle and the preceding vehicle, and the speed of the preceding vehicle through a radar sensor; calculating the speed limit requirement of the vehicle through the identification results of the camera and the radar sensor; The vehicle control unit determines the speed limit target value of the vehicle according to the gear position of the vehicle, the state of the vehicle, and the speed limit requirement, including: The vehicle control unit determines the first speed limit value of the vehicle according to the gear position of the vehicle; The vehicle control unit determines the second speed limit value of the vehicle according to the state of the vehicle; The vehicle control unit determines the third speed limit value of the vehicle according to the speed limit requirement; The minimum value among the first speed limit value, the second speed limit value, and the third speed limit value is taken as the speed limit target value of the vehicle.

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