Port automatic driving vehicle control method

Abstract

The present disclosure relates to a port automatic driving vehicle control method, comprising the following steps: step 1: obtaining a global path planning of the vehicle; step 2: calculating control information of the vehicle according to the global path planning of the vehicle, the control information comprising a target pedal opening, a target steering wheel turning angle and a target gear of the vehicle; step 3: controlling the vehicle based on the control information; the front wheel turning angle of the vehicle is in a symmetrical relationship with the rear wheel turning angle, a positioning system is installed at the center position of the vehicle, the head direction of the vehicle is the positive direction by default, in step 2, when calculating the target steering wheel turning angle, the closest point of the vehicle on the global path is calculated according to the global path planning, the included angle between the positive direction of the vehicle and the tangent direction of the closest point is calculated, and if the included angle is greater than 90°, the positive direction of the vehicle is rotated by 180°. According to the actual working condition, the driving gear of the vehicle is adjusted, the operation efficiency is effectively improved, the operation difficulty and the collision risk are reduced, and the simplicity of the target steering wheel turning angle calculation is improved.

Description

Technical Field

[0001] This disclosure relates to the field of autonomous driving technology, and in particular to a method for controlling autonomous vehicles in ports. Background Technology

[0002] As transportation hubs, ports play a crucial role in promoting international trade and regional development. With approximately 90% of global trade carried by sea, operational efficiency is paramount for ports. In the era of rapid development of "Industry 4.0" and "Internet Plus," ports are also undergoing digital and fully automated transformation and upgrading. Today, port operations are moving towards automation, with the increasing number of automated terminals and the accelerating pace of automated operations. This not only adds new vitality to ports but also saves labor costs. In the future, advancements in automation technology will further promote the intelligentization of port operations.

[0003] As ports transition towards automation, they are increasingly introducing unmanned trucks for operations. In recent years, to improve vehicle flexibility, some ports have begun introducing Intelligent Guided Vehicles (IGVs) with four-wheel steering capabilities. Related technologies include... Figure 1 and Figure 2 As shown, most IGVs in automatic driving mode only have the D gear forward function. When an IGV receives a work task, if the target starting point is behind the IGV, the IGV needs to detour around the work area (e.g., Figure 1 (As shown by the dotted line in the image) Proceed to the target starting point or drive to a more open area to make a U-turn (such as...) Figure 2 (As shown by the dotted line in the diagram) to the target starting point. This results in a longer travel distance for the unmanned truck, which is particularly noticeable in areas with large work sites, reducing the operational efficiency of the unmanned truck to some extent. Furthermore, turning around the unmanned truck increases the operational difficulty and collision risk.

[0004] In some related technologies, although unmanned trucks have a reverse gear function in autonomous driving mode, the algorithm for the steering wheel angle of unmanned trucks is complicated, making its development difficult and reducing the resource utilization of chips.

[0005] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0006] To overcome the problems existing in related technologies, this disclosure provides a method for controlling automated vehicles in ports.

[0007] According to an embodiment of this disclosure, a method for controlling an automated driving vehicle in a port is provided, comprising the following steps: Step 1: obtaining the vehicle's global path planning; Step 2: calculating the vehicle's control information based on the vehicle's global path planning, the control information including the vehicle's target pedal opening, target steering wheel angle, and target gear; Step 3: controlling the vehicle based on the control information; wherein, the vehicle's front wheel steering angle and rear wheel steering angle are symmetrical, a positioning system is installed at the center of the vehicle, and the vehicle's front direction is assumed to be the positive direction. In Step 2, when calculating the target steering wheel angle, the nearest point of the vehicle on the global path is calculated based on the vehicle's global path planning, and the angle between the vehicle's positive direction and the tangent direction of the nearest point is calculated. If the angle is greater than 90°, the vehicle's positive direction is rotated by 180°.

[0008] In one implementation, the calculation process for the target steering wheel angle includes the following steps: Step 2.1.1: Detect whether the vehicle's current gear is D or R. If so, proceed to step 2.1.2; otherwise, skip directly to the end. Step 2.1.2: Calculate the nearest point of the vehicle on the global path based on the vehicle's global path planning, and calculate the angle between the vehicle's positive direction and the tangent direction of the nearest point. Step 2.1.3: Determine whether the angle between the vehicle's positive direction and the tangent direction of the nearest point is greater than 90°. If the angle is greater than 90°, proceed to step 2.1.4; otherwise, proceed to step 2.1.6. Step 2.1.4: Set the current steering wheel angle of the vehicle... Step 2.1.5: Rotate 180° and set the reverse flag Reverse_Flg to 1; Step 2.1.6: Determine if the reverse flag Reverse_Flg is zero. If it is, proceed to step 2.1.6; otherwise, maintain the current determination state; Step 2.1.6: Based on the vehicle's positioning information and the global path, convert the global route into a local route relative to the vehicle's body; Step 2.1.7: Based on the local route and the vehicle's positioning information, calculate the target steering wheel angle using the Stanley algorithm; Step 2.1.8: Determine if the vehicle's current gear is R. If it is, the target steering wheel angle is negative; otherwise, it is positive, and the calculation of the current cycle is completed.

[0009] In one embodiment, in step 2.1.7, the target steering wheel angle is calculated using the following formulas: θ = atan(e * K_stanley / (1 + |vspd|)); δ = θ + β; where θ is the compensation value obtained from the distance e between the center of the vehicle's front axle and the nearest point, K_stanley is the adjustment gain of θ, vspd is the actual speed of the current vehicle, β is the angle between the positive direction of the vehicle and the tangent direction of the nearest point on the local route, and δ is the target steering wheel angle.

[0010] In one implementation, K_stanley takes the value 0.1.

[0011] In one implementation, the calculation process for the target gear includes the following steps: Step 2.2.1: When the vehicle first switches to autonomous driving mode, its target gear is D gear by default, and the initialized target gear is the target gear from the previous moment; Step 2.2.2: Determine whether the vehicle's actual gear is D gear or R gear. If yes, proceed to step 2.2.3; otherwise, jump directly to the end; Step 2.2.3: Determine whether the reverse flag Reverse_Flg is 1. If yes, proceed to step 2.2.4; otherwise, jump to the end; Step 2.2.4: Set the vehicle's target speed to zero; Step 2.2.5: Determine whether the absolute value of the current speed Vspd is less than the preset speed V. If yes, proceed to step 2.2.6; otherwise, jump back to step 2.2. 4; Step 2.2.6: Determine if the vehicle is currently in D gear. If yes, proceed to step 2.2.7; otherwise, jump to step 2.2.8; Step 2.2.7: Set the target gear of the vehicle to R gear and jump to step 2.2.9; Step 2.2.8: Set the target gear of the vehicle to D gear and jump to step 2.2.10; Step 2.2.9: Determine if the vehicle is currently in R gear. If yes, proceed to step 2.2.11; otherwise, jump to step 2.2.7; Step 2.2.10: Determine if the vehicle is currently in D gear. If yes, proceed to step 2.2.11; otherwise, jump to step 2.2.8; Step 2.2.11: Set the reverse flag Reverse_Flg to zero and complete the calculation of the current cycle.

[0012] In one embodiment, the preset speed V is 0.5 m / s.

[0013] In one implementation, the vehicle is an intelligent guided transport vehicle.

[0014] In one implementation, in step 1, an intelligent transportation system is used to complete the global path planning of the vehicle based on the vehicle's location information and task requirements.

[0015] In one implementation, in step 2, the autonomous driving module receives the global path plan and calculates the target pedal opening, the target steering wheel angle, and the target gear position of the vehicle based on the global path plan.

[0016] In one embodiment, in step 3, a vehicle control unit receives the target pedal opening, the target steering wheel angle, and the target gear position of the vehicle to control the vehicle speed and driving direction.

[0017] The technical solutions provided by the embodiments of this disclosure may include the following beneficial effects:

[0018] 1. The port autonomous driving vehicle control method provided in this embodiment can adjust the vehicle's driving gear according to the actual working conditions, that is, adjust the vehicle's D gear or R gear, thereby adjusting the vehicle's driving direction, effectively shortening the time and distance for the vehicle to travel to the target starting point, improving work efficiency, and reducing the difficulty of operating the vehicle and the risk of collision.

[0019] 2. By setting the steering angles of the front and rear wheels of the vehicle to be symmetrical, the minimum turning radius of the vehicle can be reduced, thereby improving steering efficiency;

[0020] 3. When calculating the target steering wheel angle, calculate the angle between the vehicle's positive direction and the tangent direction at the nearest point, and when the angle is greater than 90°, rotate the vehicle's positive direction by 180° to improve the ease of calculating the target steering wheel angle;

[0021] 4. Based on the Stanley algorithm and vehicle steering characteristics, a positioning system is designed to be installed at the center of the vehicle. It is also proposed that when driving in reverse gear, the positive direction of the positioning system be rotated by 180° to ensure the vehicle's route following in D and R gears and to simplify the calculation of the target steering wheel angle in reverse gear, thereby reducing the difficulty of algorithm development and improving the chip's resource utilization.

[0022] 5. The target steering wheel angle can be calculated using the formulas θ=atan(e*K_stanley / (1+|vspd|)) and δ=θ+β. The addition of 1+|vspd| in the denominator of these formulas ensures that the target steering wheel angle calculated at low speeds fluctuates less.

[0023] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0025] Figure 1 It is a schematic diagram of a driving route when a vehicle moves to a target starting point in autonomous driving mode, based on existing technology.

[0026] Figure 2 This is a schematic diagram of an alternative driving route for a vehicle in autonomous driving mode to reach a target starting point, based on existing technologies.

[0027] Figure 3 This is a schematic diagram illustrating the driving route of a vehicle when it moves to a target starting point using a port autonomous driving vehicle control method, according to an exemplary embodiment.

[0028] Figure 4 This is a schematic diagram illustrating the driving route of a vehicle when it moves to a target starting point using a port autonomous driving vehicle control method, according to yet another exemplary embodiment.

[0029] Figure 5 This is a flowchart illustrating a port autonomous vehicle control method according to an exemplary embodiment.

[0030] Figure 6 This is a schematic diagram of a vehicle in a port automated vehicle control method according to an exemplary embodiment.

[0031] Figure 7 This is a flowchart illustrating the calculation of the target steering wheel angle in step 2 of a port autonomous vehicle control method according to an exemplary embodiment.

[0032] Figure 8 This is a schematic diagram illustrating the formula for calculating the steering wheel angle of a target in a port autonomous vehicle control method according to an exemplary embodiment.

[0033] Figure 9 This is a flowchart illustrating the calculation of the target gear in step 2 of a port autonomous vehicle control method according to an exemplary embodiment. Detailed Implementation

[0034] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0035] To address related technical issues, this disclosure provides a port automated driving vehicle control method. Based on the IGV structure, it develops a control method that allows the vehicle to intelligently select forward or reverse gear based on actual working conditions. This method can optimize the vehicle's travel path relative to the target starting point (e.g., ...). Figure 3 As shown by the straight line in the diagram, this method effectively improves the operational efficiency of vehicles and reduces their operational difficulty and collision risk. In the port automated driving vehicle control method provided in this embodiment, the vehicle is an intelligent guided transport vehicle (i.e., IGV).

[0036] Example

[0037] Figure 3 This is a schematic diagram illustrating the driving route of a vehicle when it moves to a target starting point using a port autonomous driving vehicle control method, according to an exemplary embodiment. Figure 4 This is a schematic diagram illustrating the driving route of a vehicle when it moves to a target starting point using a port autonomous driving vehicle control method, according to yet another exemplary embodiment. Figure 5 This is a flowchart illustrating a port autonomous vehicle control method according to an exemplary embodiment. Figure 6 This is a schematic diagram of a vehicle in a port automated vehicle control method according to an exemplary embodiment.

[0038] like Figures 3 to 6 As shown, the port autonomous driving vehicle control method provided in this disclosure achieves vehicle control by combining an Intelligent Transport System (ITS), an autonomous driving module, and a Vehicle Control Unit (VCU). The front wheel steering angle and rear wheel steering angle are symmetrical, a positioning system is installed at the center of the vehicle, and the vehicle's front direction is assumed to be positive. Specifically, the method includes the following steps: Step 1: Obtain the vehicle's global path plan; Step 2: Calculate the vehicle's control information based on the global path plan, including the target pedal opening, target steering wheel angle, and target gear position; Step 3: Control the vehicle based on the control information.

[0039] In step 1, the intelligent transportation system completes global path planning for the vehicle based on vehicle information and task requirements, and sends it to the autonomous driving module. Vehicle information includes the vehicle's location information. In step 2, the autonomous driving module receives the global path plan and calculates the required target pedal opening, target steering wheel angle, and target gear position, then sends corresponding control commands to the vehicle control unit. Furthermore, when calculating the target steering wheel angle, the system calculates the closest point on the global path based on the global path plan and calculates the angle between the vehicle's positive direction and the tangent direction of the closest point. If the angle is greater than 90°, the vehicle's positive direction is rotated 180°. In step 3, the vehicle control unit executes corresponding controls based on the control commands, controlling the vehicle's speed and direction of travel, thereby moving the vehicle to the target starting position.

[0040] The port autonomous driving vehicle control method provided in this disclosure can adjust the vehicle's driving gear according to actual working conditions, i.e., adjust the vehicle to D or R gear, thereby adjusting the vehicle's driving direction. This effectively shortens the time and distance for the vehicle to reach the target starting point, improves operational efficiency, and reduces the difficulty of vehicle operation and the risk of collision. Furthermore, by setting the front wheel steering angle and rear wheel steering angle to be symmetrical, the minimum turning radius of the vehicle is reduced, improving steering efficiency. When calculating the target steering wheel angle, the angle between the vehicle's positive direction and the tangent direction of the nearest point is calculated. When this angle is greater than 90°, the vehicle's positive direction is rotated by 180° to improve the simplicity of the target steering wheel angle calculation, reduce the difficulty of algorithm development, and improve chip resource utilization.

[0041] It should be noted that in step 2 of the port autonomous vehicle control method provided in this embodiment, the target pedal opening depends on the target vehicle speed, and its algorithm is similar to that of the prior art, so it will not be described in detail here.

[0042] Figure 7 This is a flowchart illustrating the calculation of the target steering wheel angle in step 2 of a port autonomous vehicle control method according to an exemplary embodiment.

[0043] like Figure 7As shown, in step 2, the calculation process for the target steering wheel angle includes the following steps: Step 2.1.1: Detect whether the vehicle's current gear is D or R. If so, proceed to step 2.1.2; otherwise, skip directly to the end. Step 2.1.2: Calculate the vehicle's closest point on the global path based on the vehicle's global path planning, and calculate the angle between the vehicle's positive direction and the tangent direction of the closest point. Step 2.1.3: Determine whether the angle between the vehicle's positive direction and the tangent direction of the closest point is greater than 90°. If the angle is greater than 90°, proceed to step 2.1.4; otherwise, proceed to step 2.1.6. Step 2.1.4: Rotate the current vehicle's positive direction by 18 degrees. 0°, set the reverse flag Reverse_Flg to 1; Step 2.1.5: Determine if the reverse flag Reverse_Flg is zero. If it is, proceed to step 2.1.6; otherwise, maintain the current determination state; Step 2.1.6: Based on the vehicle's positioning information and global path, convert the global route into a local route relative to the vehicle's body; Step 2.1.7: Based on the local route and the vehicle's positioning information, calculate the target steering wheel angle using the Stanley algorithm; Step 2.1.8: Determine if the vehicle's current gear is R. If it is, the target steering wheel angle is negative; otherwise, it is positive, and the calculation of the current cycle is completed.

[0044] Figure 8 This is a schematic diagram illustrating the formula for calculating the steering wheel angle of a target in a port autonomous vehicle control method according to an exemplary embodiment.

[0045] In step 2.1.7, the target steering wheel angle is calculated using the following formula:

[0046] θ=atan(e*K_stanley / (1+|vspd|)) and δ=θ+β; where, as Figure 8 As shown, θ is the compensation value obtained from the distance e between the center of the vehicle's front axle and the nearest point, K_stanley is the adjustment gain of θ, vspd is the actual speed of the current vehicle, β is the angle between the positive direction of the vehicle and the tangent direction of the nearest point on the local route, and δ is the target steering wheel angle. In this embodiment, K_stanley is set to 0.1. It can be seen that the calculation formula for the target steering wheel angle is simple. When the vehicle is moved to the target starting point, the target steering wheel angle δ is calculated using this formula. It is only necessary to determine whether the vehicle's current gear is R (reverse). If the vehicle is in R, the target steering wheel angle δ is negative; if the vehicle is not in R (e.g., D), the target steering wheel angle δ is positive. This effectively improves the simplicity of calculating the target steering wheel angle δ, improves the vehicle's steering efficiency, effectively reduces the development difficulty of the target steering wheel angle algorithm, and improves the resource utilization of the chip.

[0047] Furthermore, in the above relationship, by using 1+|vspd| in the denominator, we can ensure that the target steering wheel angle calculated when the vehicle is traveling at low speed fluctuates less.

[0048] Figure 9 This is a flowchart illustrating the calculation of the target gear in step 2 of a port autonomous vehicle control method according to an exemplary embodiment.

[0049] like Figure 9 As shown, in step 2, the calculation process for the target gear includes the following steps: Step 2.2.1: When the vehicle first switches to autonomous driving mode, its target gear is D gear by default, and the initialized target gear is the target gear from the previous moment; Step 2.2.2: Determine whether the vehicle's actual gear is D gear or R gear. If yes, proceed to step 2.2.3; otherwise, jump directly to the end; Step 2.2.3: Determine whether the reverse flag Reverse_Flg is 1. If yes, proceed to step 2.2.4; otherwise, jump to the end; Step 2.2.4: Set the vehicle's target speed to zero; Step 2.2.5: Determine whether the absolute value of the current speed Vspd is less than the preset speed V. If yes, proceed to step 2.2.6; otherwise, jump to step 2.2.4. Step 2.2.6: Determine if the vehicle is currently in D gear. If yes, proceed to step 2.2.7; otherwise, jump to step 2.2.8. Step 2.2.7: Set the target gear of the vehicle to R gear and jump to step 2.2.9. Step 2.2.8: Set the target gear of the vehicle to D gear and jump to step 2.2.10. Step 2.2.9: Determine if the vehicle is currently in R gear. If yes, proceed to step 2.2.11; otherwise, jump to step 2.2.7. Step 2.2.10: Determine if the vehicle is currently in D gear. If yes, proceed to step 2.2.11; otherwise, jump to step 2.2.8. Step 2.2.11: Set the reverse flag Reverse_Flg to zero and complete the calculation of the current cycle.

[0050] It should be noted that in this embodiment of the present disclosure, when the angle between the vehicle's positive direction and the tangent direction of the nearest point is greater than 90°, the current positive direction of the vehicle will be rotated by 180° and the reverse flag Reverse_Flg will be set to 1 until the gear shifting action is completed and the reverse flag Reverse_Flg will be set to zero.

[0051] In the calculation process of the target gear, the preset speed V in step 2.2.5 is set to 0.5m / s. Step 2.2.5 ensures the reliability and safety of the vehicle's 180° forward rotation.

[0052] In summary, the port autonomous driving vehicle control method provided in this disclosure adopts an IGV (Intelligent Guided Vehicle) structure. By using a vehicle with a symmetrical relationship between the front and rear wheel steering angles (i.e., dual-axle or four-wheel steering), the minimum turning radius of the vehicle is reduced, improving steering efficiency. The vehicle can intelligently select either D or R gear according to actual working conditions to move the vehicle to the target starting point with the shortest travel distance, effectively improving operational efficiency, reducing operational difficulty and collision risk, and enhancing driving safety. Based on the Stanley algorithm and vehicle steering characteristics, the positioning system is designed to be installed at the center of the vehicle. Furthermore, when driving in reverse gear, the vehicle's forward direction is rotated 180° by the positioning system, ensuring the vehicle's route following accuracy in both D and R gears and simplifying the calculation of the target steering wheel angle in reverse gear. Therefore, when the vehicle is in R gear (reverse gear), the target steering wheel angle calculated using the formula can be taken as a negative value, effectively reducing the algorithm development difficulty and improving chip resource utilization.

[0053] It is understood that in this disclosure, "multiple" refers to two or more, and other quantifiers are similar. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. The singular forms "a," "the," and "the" are also intended to include the plural forms unless the context clearly indicates otherwise.

[0054] It is further understood that the terms "first," "second," etc., are used to describe various types of information, but this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another, and do not indicate a specific order or degree of importance. In fact, the expressions "first," "second," etc., are completely interchangeable. For example, without departing from the scope of this disclosure, first information can also be referred to as second information, and similarly, second information can also be referred to as first information.

[0055] It is further understood that the terms “center,” “longitudinal,” “lateral,” “front,” “rear,” “up,” “down,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” and “outer,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this embodiment and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation.

[0056] It can be further understood that, unless otherwise specified, "connection" includes both direct connections where no other components exist between the two parties and indirect connections where other components exist between them.

[0057] It is further understood that although operations are described in a specific order in the accompanying drawings in the embodiments of this disclosure, this should not be construed as requiring these operations to be performed in the specific order or serial order shown, or requiring all of the shown operations to be performed to obtain the desired result. In certain environments, multitasking and parallel processing may be advantageous.

[0058] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0059] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A method for controlling automated vehicles in ports, characterized in that, Includes the following steps: Step 1: Obtain the vehicle's global path plan; Step 2: Calculate the control information of the vehicle based on the global path planning of the vehicle. The control information includes the target pedal opening, target steering wheel angle, and target gear position of the vehicle. Step 3: Control the vehicle based on the control information; The front wheel steering angle and the rear wheel steering angle of the vehicle are symmetrical. A positioning system is installed at the center of the vehicle. The vehicle's front direction is the default positive direction. In step 2, when calculating the target steering wheel angle, the nearest point of the vehicle on the global path is calculated based on the vehicle's global path planning. The angle between the vehicle's positive direction and the tangent direction of the nearest point is calculated. If the angle is greater than 90°, the vehicle's positive direction is rotated by 180°. The calculation process for the target steering wheel angle includes the following steps: Step 2.1.1: Detect whether the vehicle is currently in D or R gear. If so, proceed to step 2.1.2; otherwise, skip directly to the end. Step 2.1.2: Calculate the nearest point of the vehicle on the global path based on the global path planning of the vehicle, and calculate the angle between the positive direction of the vehicle and the tangent direction of the nearest point; Step 2.1.3: Determine whether the angle between the positive direction of the vehicle and the tangent direction of the nearest point is greater than 90°. If the angle is greater than 90°, proceed to step 2.1.4; otherwise, proceed to step 2.1.

6. Step 2.1.4: Rotate the current vehicle's forward direction by 180° and set the reverse flag Reverse_Flg to 1; Step 2.1.5: Determine if the reverse flag Reverse_Flg is zero. If it is, proceed to step 2.1.6; otherwise, maintain the current determination state. Step 2.1.6: Based on the vehicle's location information and the global path, convert the global route into a local route relative to the vehicle's body. Step 2.1.7: Based on the local route and the vehicle's positioning information, the target steering wheel angle is calculated using the Stanley algorithm; Step 2.1.8: Determine whether the current gear of the vehicle is R gear. If it is, the target steering wheel angle is set to a negative value; otherwise, it is set to a positive value, and the calculation of the current cycle is completed. The calculation process for the target gear includes the following steps: Step 2.2.1: When the vehicle is first switched to autonomous driving mode, its target gear is set to D gear by default. The target gear after initialization is the target gear set at the previous moment. Step 2.2.2: Determine whether the vehicle is actually in D or R gear. If so, proceed to step 2.2.3; otherwise, skip directly to the end. Step 2.2.3: Determine if the reverse flag Reverse_Flg is 1. If it is, proceed to step 2.2.4; otherwise, jump to the end. Step 2.2.4: Set the target speed of the vehicle to zero; Step 2.2.5: Determine whether the absolute value of the current vehicle speed Vspd is less than the preset speed V. If it is, proceed to step 2.2.6; otherwise, jump to step 2.2.

4. Step 2.2.6: Determine if the vehicle is currently in Drive (D) gear. If yes, proceed to Step 2.2.7; otherwise, proceed to Step 2.2.

8. Step 2.2.7: Set the target gear of the vehicle to R gear, and proceed to step 2.2.9; Step 2.2.8: Set the target gear of the vehicle to D gear, and proceed to step 2.2.10; Step 2.2.9: Determine if the vehicle is currently in reverse (R). If so, proceed to step 2.2.11; otherwise, proceed to step 2.2.

7. Step 2.2.10: Determine if the vehicle is currently in D gear. If so, proceed to step 2.2.11; otherwise, proceed to step 2.2.

8. Step 2.2.11: Set the reverse flag Reverse_Flg to zero and complete the calculation for the current loop cycle; In step 2.1.7, the target steering wheel angle is calculated using the following formula: θ=atan(e*K_stanley / (1+|vspd|)); δ = θ + β; Where θ is the compensation value obtained from the distance e between the center of the vehicle's front axle and the nearest point, K_stanley is the adjustment gain of θ, vspd is the actual speed of the current vehicle, β is the angle between the positive direction of the vehicle and the tangent direction of the nearest point on the local route, and δ is the target steering wheel angle. The value of K_stanley is 0.

1.

2. The port automated driving vehicle control method according to claim 1, characterized in that: The preset speed V is 0.5 m / s.

3. The port automated driving vehicle control method according to claim 1, characterized in that: The vehicle in question is an intelligent guided transport vehicle.

4. The port automated driving vehicle control method according to claim 1, characterized in that: In step 1, an intelligent transportation system is used to complete the global path planning for the vehicle based on its location information and task requirements.

5. The port automated driving vehicle control method according to claim 1, characterized in that: In step 2, the autonomous driving module receives the global path plan and calculates the target pedal opening, the target steering wheel angle, and the target gear position of the vehicle based on the global path plan.

6. The port automated driving vehicle control method according to claim 1, characterized in that: In step 3, the vehicle control unit receives the target pedal opening, the target steering wheel angle, and the target gear position of the vehicle to control the vehicle speed and driving direction.

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