Intelligent transport vehicle steering speed control method and device, medium and electronic equipment

Abstract

Embodiments of the present application disclose a kind of intelligent transport vehicle steering speed control method, device, medium and electronic equipment.The method comprises: according to the current speed of intelligent transport vehicle, from the road image where the intelligent transport vehicle is located, select safe speed regulation road area;Calculate the lane line curvature of the safe speed regulation road area;According to the lane line curvature, determine the direction of travel and steering speed of the intelligent transport vehicle.The present application provides sufficient buffer distance for the intelligent transport vehicle to adjust the current speed to the speed suitable for turning by setting safe speed regulation road area, and realizes smooth speed regulation;The embodiments of the present application also accurately determine the direction of travel and steering speed of the intelligent transport vehicle according to lane line curvature, while taking into account the transport speed, ensure the stability of intelligent transport vehicle turning.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of computer application, and particularly relate to a steering speed control method and device for an intelligent transport vehicle, a medium and an electronic device. BACKGROUND

[0002] With the continuous development of the economy and society, the tooling manufacturing industry is gradually transforming from the traditional pure mechanical mode to digital manufacturing, and the intelligence and automation of the equipment used in the tooling manufacturing site are also gradually improving.

[0003] In the tooling production process, material transportation is usually involved. Currently, most tooling manufacturing companies use material transfer devices such as AGV (Automated Guided Vehicle) transport vehicles to transport materials instead of the traditional manual material transfer method, which greatly promotes the industrial upgrading of tooling production. The AGV transport vehicle used by the tooling manufacturing company mainly uses magnetic strip navigation, electromagnetic navigation, optical navigation, or visual navigation to navigate during material transportation. The above-mentioned methods can only provide route navigation for the AGV transport vehicle and cannot control the speed of the transport vehicle. Once working in a tooling production site with many bends, it is difficult for the AGV transport vehicle to balance the transportation speed while smoothly turning. SUMMARY

[0004] Embodiments of the present application provide a steering speed control method and device for an intelligent transport vehicle, a medium and an electronic device, which can control the speed of the intelligent transport vehicle turning to achieve the purpose of balancing the transportation speed while ensuring the stability of the intelligent transport vehicle turning.

[0005] In a first aspect, embodiments of the present application provide a steering speed control method for an intelligent transport vehicle, the method comprising:

[0006] selecting a safe speed regulation road area from a road image in which the intelligent transport vehicle is located according to a current speed of the intelligent transport vehicle;

[0007] calculating a lane line curvature of the safe speed regulation road area;

[0008] determining a traveling direction and a steering speed of the intelligent transport vehicle according to the lane line curvature.

[0009] In a second aspect, embodiments of the present application provide a steering speed control device for an intelligent transport vehicle, the device comprising:

[0010] a safe speed regulation road area determination module configured to select a safe speed regulation road area from a road image in which the intelligent transport vehicle is located according to a current speed of the intelligent transport vehicle;

[0011] a lane line curvature calculation module configured to calculate a lane line curvature of the safe speed regulation road region;

[0012] an intelligent transport vehicle traveling direction and steering speed determination module configured to determine a traveling direction and a steering speed of the intelligent transport vehicle according to the lane line curvature.

[0013] In a third aspect, an embodiment of the present application provides a computer readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the intelligent transport vehicle steering speed control method according to the embodiments of the present application.

[0014] In a fourth aspect, an embodiment of the present application provides an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable by the processor, and the processor implements the intelligent transport vehicle steering speed control method according to the embodiments of the present application when executing the computer program.

[0015] The technical solution provided by the embodiments of the present application selects a safe speed regulation road region from a road image in which the intelligent transport vehicle is located according to a current speed of the intelligent transport vehicle, calculates a lane line curvature of the safe speed regulation road region, and determines a traveling direction and a steering speed of the intelligent transport vehicle according to the lane line curvature. The technical solution provides a sufficient buffer distance for adjusting the current speed of the intelligent transport vehicle to a speed suitable for turning by setting the safe speed regulation road region, and realizes smooth speed regulation. The embodiments of the present application also accurately determine the traveling direction and the steering speed of the intelligent transport vehicle according to the lane line curvature, which guarantees the turning stability of the intelligent transport vehicle while taking into account the transport speed. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1A is a flowchart of the intelligent transport vehicle steering speed control method provided by an embodiment of the present application;

[0017] Figure 1B is a road image in which an intelligent transport vehicle is located according to an embodiment of the present application;

[0018] Figure 1C is a schematic diagram of a safe speed regulation road region selected from a road image in which an intelligent transport vehicle is located according to an embodiment of the present application;

[0019] Figure 1D is a lane line extracted from a bird's eye view corresponding to a safe speed regulation road region according to an embodiment of the present application;

[0020] Figure 2 is a flowchart of another intelligent transport vehicle steering speed control method provided by an embodiment of the present application;

[0021] Figure 3is a flow chart of another intelligent transport vehicle steering speed control method provided in Embodiment Three of the present application;

[0022] Figure 4A is a flow chart of another intelligent transport vehicle steering speed control method provided in Embodiment Four of the present application;

[0023] Figure 4B is a schematic diagram of a horizontal distance determination process between a road image center and a lane center provided in the present application.

[0024] Figure 5 is a structural schematic diagram of an intelligent transport vehicle steering speed control device provided in Embodiment Five of the present application;

[0025] Figure 6 is a structural schematic diagram of an electronic device provided in Embodiment Seven of the present application. DETAILED DESCRIPTION

[0026] The present application will be further described below in conjunction with the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application. In addition, it should be noted that, for the convenience of description, only the parts related to the present application are shown in the drawings, but not all the structures.

[0027] Before the example embodiments are discussed in more detail, it should be mentioned that some of the example embodiments are described as processes or methods depicted as flow charts. Although the flow charts describe the steps in a sequential order, many of the steps can be performed in parallel, concurrently or at the same time. In addition, the order of the steps can be rearranged. The processes can be terminated when their operations are completed, but can also have additional steps not included in the flow charts. The processes can correspond to methods, functions, routines, subroutines, subprograms, etc.

[0028] Embodiment One

[0029] Figure 1A is a flow chart of an intelligent transport vehicle steering speed control method provided in Embodiment One of the present application. The present embodiment can be applicable to control the steering speed of the intelligent transport vehicle when the intelligent transport vehicle is steering, to ensure that the intelligent transport vehicle steers stably. The method can be executed by the intelligent transport vehicle steering speed control device provided in the present application. The device can be realized by software and / or hardware, and can be integrated in an electronic device running the system.

[0030] As shown in Figure 1A the intelligent transport vehicle steering speed control method comprises:

[0031] S110, selecting a safe speed adjusting road region from a road image in which the intelligent transportation vehicle is located according to a current speed of the intelligent transportation vehicle.

[0032] The intelligent transportation vehicle refers to a vehicle that can automatically operate according to a set mode without supervision. For example, the intelligent transportation vehicle is an intelligent trolley used for transporting materials in an industrial site. The current speed refers to the driving speed of the intelligent transportation vehicle at the current time. For example, the current speed can be collected by a sensor configured on the vehicle.

[0033] The road image in which the intelligent transportation vehicle is located refers to an image including a lane in which the intelligent transportation vehicle is scheduled to travel, which is taken at a same angle as a driving direction of the intelligent transportation vehicle with the intelligent transportation vehicle as a first view. Specifically, the road image is collected by an image collection device such as a camera configured on the intelligent transportation vehicle. To ensure the quality of the road image, the image collection device can be calibrated before collecting an original road image. Specifically, the horizontal and lateral positions of the camera are calibrated to ensure that the installation position of the camera is fixed. The distortion coefficient of the camera is obtained by using a function cv2.calibrateCamera() provided by OPENCV. The image is corrected for distortion by using a function cv2.undistort() provided by OPENCV and inputting the calculated distortion parameters. Figure 1B The road image in which the intelligent transportation vehicle is located provided by the embodiment of the present application.

[0034] The safe speed adjusting road region refers to a transition region corresponding to a world coordinate system in which the intelligent transportation vehicle is scheduled to travel at a target speed, which is set in the road image. The target speed refers to the maximum driving speed that can ensure smooth turning of the intelligent transportation vehicle. In the case where the installation position of the image collection device is fixed, the size of the safe speed adjusting road region is related to the driving speed of the intelligent transportation vehicle at the current time. Generally, the speed of the intelligent transportation vehicle in the case of turning is lower than the speed of the intelligent transportation vehicle in the case of driving on a straight road. To improve the driving safety of the intelligent transportation vehicle, the speed is adjusted in the safe speed adjusting road region, and the current speed is generally reduced to the target speed. To realize smooth speed adjustment of the intelligent transportation vehicle, the safe speed adjusting road region with a longer longitudinal distance is set in the case where the speed is higher.

[0035] The safe speed adjusting road region is selected from the road image in which the intelligent transportation vehicle is located according to the current speed of the intelligent transportation vehicle. For example, the safe speed adjusting road region can be determined by the following formula in the world coordinate system:

[0036] D = V * k

[0037] Wherein, k refers to the relationship coefficient, k is an empirical value determined by the relevant technical personnel according to the actual situation, which is not limited here; V represents the current vehicle speed, and D represents the safe speed regulation distance.

[0038] After obtaining the safe speed regulation distance, the current position of the intelligent transportation vehicle is taken as the starting point, and the road region with the same length as the safe speed regulation distance is determined as the safe speed regulation road region in the world coordinate system along the driving direction of the intelligent transportation vehicle. Then, the safe speed regulation road region is mapped from the world coordinate system to the camera coordinate system, and the safe speed regulation road region is determined in the road image. It should be noted that the following safe speed regulation road regions refer to the safe speed regulation road regions in the road image in the camera coordinate system. Figure 1C A schematic diagram of the safe speed regulation road region selected in the road image of the intelligent transportation vehicle provided by the embodiment of the present application is shown in FIG. 2. Figure 1C As shown in FIG. 2, the safe speed regulation road region is a white dotted quadrilateral region.

[0039] Optionally, after determining the safe speed regulation road region in the road image, perspective transformation is performed on the road image in the safe speed regulation road region. Specifically, the function cv2.getPerspectiveTransform() provided by OPENCV is used to perform perspective transformation on the safe speed regulation road region, which is converted into a bird's eye view, and the lane line in the road image is extracted in the bird's eye view. Figure 1D The lane line extracted in the bird's eye view corresponding to the safe speed regulation road region provided by the embodiment of the present application is shown in FIG. 3. In extracting the lane line, any existing lane line extraction method can be used, which is not limited here. For example, the edge algorithm of the function cv2.Sobel() provided by OPENCV can be used to set the feature block of lane edge mutation, extract the lane edge mutation, and obtain the lane line.

[0040] S120, calculating the lane line curvature of the safe speed regulation road region.

[0041] Wherein, the lane line curvature refers to the curvature of the lane line in the safe speed regulation road region. Specifically, the curve fitting method such as the least square method can be used to fit the lane line in the road region, obtain the fitting curve, and calculate the curvature of the fitting curve as the lane line curvature of the safe speed regulation road region. The lane line curvature reflects the bending degree of the lane. The greater the lane line curvature, the more curved the lane. The greater the possibility of the intelligent transportation vehicle deviating from the lane when driving into the road section.

[0042] S130, determining the driving direction and steering speed of the intelligent transportation vehicle according to the lane line curvature.

[0043] The lane line curvature represents the degree of lane deviation from a straight line. In order to ensure that the intelligent transport vehicle stably enters a curved road section and does not deviate from the predetermined lane, the steering speed and the travel direction of the intelligent transport vehicle need to be determined according to the lane line curvature.

[0044] The technical scheme provided in the embodiments of the present application selects a safe speed regulation road region from a road image in which the intelligent transport vehicle is located according to the current speed of the intelligent transport vehicle, calculates the lane line curvature of the safe speed regulation road region, and determines the travel direction and the steering speed of the intelligent transport vehicle according to the lane line curvature. The safe speed regulation road region provides sufficient buffer distance for the intelligent transport vehicle to adjust the current speed to a speed suitable for turning, and smooth speed regulation is achieved. The embodiments of the present application also accurately determine the travel direction and the steering speed of the intelligent transport vehicle according to the lane line curvature, which ensures the stability of the intelligent transport vehicle while taking into account the transport speed.

[0045] Embodiment Two

[0046] Figure 2 FIG. 2 is a flowchart of another intelligent transport vehicle steering speed control method provided in Embodiment Two of the present application. The present embodiment is further optimized on the basis of the above-mentioned embodiments. Specifically, the determination of the steering speed of the intelligent transport vehicle according to the lane line curvature includes: determining the maximum steering speed of the intelligent transport vehicle according to the lane line curvature, the road surface friction coefficient and the vehicle body weight; and determining the safe steering speed of the intelligent transport vehicle according to the maximum steering speed and a preset safety speed coefficient, as the steering speed of the intelligent transport vehicle.

[0047] As shown in FIG. 2, the intelligent transport vehicle steering speed control method includes: Figure 2

[0048] S210, selecting a safe speed regulation road region from a road image in which the intelligent transport vehicle is located according to the current speed of the intelligent transport vehicle.

[0049] S220, calculating the lane line curvature of the safe speed regulation road region.

[0050] In order to improve the calculation accuracy of the lane line curvature, in an optional embodiment, the calculation of the lane line curvature of the safe speed regulation road region includes: dividing the lane line in the safe speed regulation road region to obtain at least two lane line sub-regions; calculating the curvature of the lane line in each lane line sub-region as a candidate lane line curvature; and selecting the lane line curvature of the safe speed regulation road region from the at least two candidate lane line curvatures.

[0051] ​The lane line sub-region is a part of the safe speed regulation road region including a lane line, and the number of the lane line sub-regions is at least two. It can be known that the more the number of the lane line sub-regions is, the higher the accuracy of the calculated lane line curvature is, and the more the calculation resources required are occupied. The specific number of the lane line sub-regions is not limited here and is determined according to actual conditions. For example, the number of the lane line sub-regions is 6.

[0052] The lane line in the safe speed regulation road region is divided to obtain at least two lane line sub-regions. For example, the lane line in the safe speed regulation road region can be equally divided in a direction parallel to the vertical boundary of the road image to obtain the lane line sub-regions. The curvatures of the lane lines in the respective lane line sub-regions are calculated. Specifically, a curve fitting algorithm can be used to fit the lane line in the lane line sub-region to calculate the curvature of the fitted curve as a candidate lane line curvature. There is a corresponding candidate lane line curvature for each lane line sub-region. The lane line curvature of the safe speed regulation road region is selected from the at least two candidate lane line curvatures. Preferably, the largest one in the numerical value among all the candidate lane line curvatures is selected as the lane line curvature of the safe speed regulation road region.

[0053] S230, determining the maximum steering speed of the intelligent transportation vehicle according to the lane line curvature, the road surface friction coefficient, and the vehicle body weight.

[0054] The road surface friction coefficient can reflect the lateral braking performance provided by the road surface during the driving of the intelligent transportation vehicle. The road surface friction coefficient is related to the material of the road. For example, the road surface friction coefficient of an asphalt road is 0.9. In the embodiments of the present application, the road surface friction coefficient is a constant that remains unchanged. The specific value of the road surface friction coefficient is not limited here and is determined according to actual conditions. The vehicle body weight refers to the weight of the intelligent transportation vehicle itself. The maximum steering speed refers to the maximum driving speed allowed by the intelligent transportation vehicle when turning.

[0055] The maximum steering speed of the intelligent transportation vehicle is determined according to the lane line curvature, the road surface friction coefficient, and the vehicle body weight. Specifically, the maximum steering speed of the intelligent transportation vehicle can be determined according to the following formula:

[0056]

[0057] wherein V is the current speed, u represents the ground friction coefficient, g is the vehicle body weight, R is the reciprocal of the lane line curvature, and indicates the steering radius. In the case where u, g, and R are known, the above formula is transformed to obtain

[0058] S240, determining a safe steering speed of the intelligent transport vehicle as the steering speed of the intelligent transport vehicle according to the maximum steering speed and a preset safe speed coefficient.

[0059] The preset safe speed coefficient is an experience value determined by a relevant technical person according to an actual situation, specifically, the preset safe speed coefficient is a number between 0 and 1, and the safe steering speed of the intelligent transport vehicle is determined according to the maximum steering speed and the preset safe speed coefficient, specifically, the product of the maximum steering speed and the preset safe speed coefficient can be taken as the safe steering speed of the intelligent transport vehicle. In this way, the intelligent transport vehicle can be ensured to turn stably.

[0060] The technical scheme provided by the embodiment of the application selects a safe speed regulation road area from a road image in which the intelligent transport vehicle is located according to the current speed of the intelligent transport vehicle, calculates the lane line curvature of the safe speed regulation road area, determines the maximum steering speed of the intelligent transport vehicle according to the lane line curvature, a road surface friction coefficient and a vehicle body weight, and determines a safe steering speed of the intelligent transport vehicle according to the maximum steering speed and a preset safe speed coefficient, as the steering speed of the intelligent transport vehicle. The maximum steering speed of the intelligent transport vehicle is determined according to the curvature of the road on which the intelligent transport vehicle travels, and the safe steering speed is determined according to the maximum steering speed, which avoids the situation that differential steering deviates from a predetermined lane, and at the same time ensures transport efficiency.

[0061] Embodiment three

[0062] Figure 3 is a flowchart of another intelligent transport vehicle steering speed control method provided by the embodiment three of the application. The embodiment is further optimized on the basis of the above-mentioned embodiments. Specifically, the optimization is that the traveling direction of the intelligent transport vehicle is determined according to the lane line curvature, including: determining a maximum curvature position in the road image according to the lane line curvature; wherein the road image includes at least two parallel lane lines; determining a midpoint of a horizontal line connecting two adjacent lane lines as a lane center according to the maximum curvature position; wherein a straight line determined by the lane center and the maximum curvature position is parallel to the horizontal boundary of the road image; and determining the traveling direction of the intelligent transport vehicle according to the center of the road image, the lane center and a preset steering reference value.

[0063] As shown in Figure 3 , the intelligent transport vehicle steering speed control method includes:

[0064] S310, selecting a safe speed regulation road area from a road image in which the intelligent transport vehicle is located according to the current speed of the intelligent transport vehicle.

[0065] S320, calculate lane line curvatures of the safe speed regulation road region.

[0066] S330, determine a maximum curvature position in the road image according to the lane line curvatures; wherein the road image comprises at least two parallel lane lines.

[0067] The maximum curvature position is a position where the lane line curvatures in the safe speed regulation road region in the road image are maximum. It can be known that two parallel lane lines can determine a lane, and the road image comprises at least two parallel lane lines, and the road image at least comprises a predetermined lane where the intelligent transportation vehicle is located.

[0068] S340, determine a midpoint of a horizontal line connecting two adjacent lane lines as a lane center according to the maximum curvature position; wherein a straight line determined by the lane center and the maximum curvature position is parallel to a horizontal boundary of the road image.

[0069] The two adjacent lane lines can determine a lane, and the lane is the predetermined lane where the intelligent transportation vehicle is located. The midpoint of the horizontal line connecting the two adjacent lane lines is the midpoint of the lane where the intelligent transportation vehicle is located. Specifically, a straight line passing through the maximum curvature position and parallel to the horizontal boundary of the road image can be drawn according to the coordinate value of the maximum curvature position in the image coordinate system. The straight line has one intersection point with each of the two adjacent lane lines that determine the lane. The midpoint of the line segment determined by the two intersection points is the lane center.

[0070] S350, determine a traveling direction of the intelligent transportation vehicle according to the center of the road image, the lane center, and a preset steering reference value.

[0071] The preset steering reference value is a standard for judging whether the intelligent transportation vehicle deviates from the lane, and is an empirical value determined by a relevant technical person according to lane properties such as lane width and lane curvature degree, and actual driving conditions of the intelligent transportation vehicle, which is not limited here and is determined according to actual conditions. Exemplarily, the preset steering reference value can be 0.7 meters.

[0072] Since the road image is collected by the image collection device arranged on the intelligent transportation vehicle, the center of the road image can reflect the current position of the intelligent transportation vehicle. The lane center is the center position of the lane where the intelligent transportation vehicle is located. According to the lane center and the center of the road image, the deviation of the intelligent transportation vehicle relative to the lane center can be determined, and then the traveling direction of the intelligent transportation vehicle can be determined.

[0073] The embodiment of the present application calculates the lane line curvature of the safe speed regulation road region, then determines the lane center according to the maximum curvature position, determines the offset of the intelligent transportation vehicle relative to the lane center according to the road image center and the lane center, and then determines the travel direction of the intelligent transportation vehicle according to the offset and the preset steering reference value, so as to correct the travel direction of the intelligent transportation vehicle. The travel direction of the intelligent transportation vehicle is determined according to the actual driving condition of the intelligent transportation vehicle, so that the intelligent transportation vehicle is prevented from deviating from the predetermined lane.

[0074] Embodiment four

[0075] Figure 4A is a flowchart of another intelligent transportation vehicle steering speed control method provided by the fourth embodiment of the present application. The present embodiment is further optimized on the basis of the above-mentioned embodiments. The specific optimization is that the travel direction of the intelligent transportation vehicle is determined according to the center of the road image, the lane center and the preset steering reference value, which includes: calculating the horizontal distance between the center of the road image and the lane center, and if the absolute value of the horizontal distance is less than or equal to the preset steering reference value, then the travel direction of the intelligent transportation vehicle is determined according to the relative position of the center of the road image and the lane center; otherwise, a route offset warning is generated and the intelligent transportation vehicle is controlled to stop.

[0076] As shown in Figure 4A , the intelligent transportation vehicle steering speed control method includes:

[0077] S410, according to the current speed of the intelligent transportation vehicle, selecting a safe speed regulation road region from the road image where the intelligent transportation vehicle is located.

[0078] S420, calculating the lane line curvature of the safe speed regulation road region.

[0079] S430, determining the maximum curvature position in the road image according to the lane line curvature; wherein the road image includes at least two parallel lane lines.

[0080] S440, determining the midpoint of the horizontal connecting line between the two adjacent lane lines as the lane center according to the maximum curvature position; wherein the straight line determined by the lane center and the maximum curvature position is parallel to the horizontal boundary of the road image.

[0081] S450, calculating the horizontal distance between the center of the road image and the lane center, and if the absolute value of the horizontal distance is less than or equal to the preset steering reference value, then the travel direction of the intelligent transportation vehicle is determined according to the relative position of the center of the road image and the lane center.

[0082] The horizontal distance between the center of the road image and the center of the lane reflects the offset of the intelligent transportation vehicle from the center of the lane. If the absolute value of the horizontal distance is less than or equal to a preset steering reference value, it indicates that the intelligent transportation vehicle is not offset from the predetermined lane.

[0083] Specifically, according to the relative position of the center of the road image and the center of the lane, it can be determined whether the intelligent transportation vehicle is close to the left lane line or the right lane line, and then it can be determined whether the intelligent transportation vehicle should move left or right to ensure that the intelligent transportation vehicle does not deviate from the predetermined lane. The left and right orientation concepts of the left lane line, the right lane line, moving left and moving right appearing in the examples of the present application are determined based on the driving direction of the intelligent transportation vehicle.

[0084] Figure 4B A schematic diagram of the process of determining the horizontal distance between the center of the road image and the center of the lane is provided for the embodiments of the present application. As shown in Figure 4B Dp is the center of the lane, Dps is the center of the road image, and S is the horizontal distance between the center of the road image and the center of the lane.

[0085] In an optional embodiment, the driving direction of the intelligent transportation vehicle is determined according to the relative position of the center of the road image and the center of the lane, which includes: taking a straight line passing through the center of the road image and parallel to the vertical boundary of the road image as a dividing line; and determining the rotational speeds of the left and right motors of the intelligent transportation vehicle according to the relative position relationship between the center of the lane and the dividing line to control the steering of the intelligent transportation vehicle.

[0086] The speed of the intelligent transportation vehicle is controlled by the rotational speed of the motor. Specifically, the left and right drive wheels of the intelligent transportation vehicle are controlled by the left and right motors, respectively. The steering of the intelligent transportation vehicle is specifically achieved by controlling the rotational speeds of the left and right motors to control the wheel speeds of the left and right drive wheels, respectively. Optionally, the output voltage of the left and right motors is controlled by adjusting the PWM (Pulse Width Modulation) frequency of the left and right motors, thereby achieving the effect of controlling the wheel speeds of the left and right drive wheels, and then completing the differential steering.

[0087] The driving direction of the intelligent transportation vehicle is determined according to the relative position of the center of the lane and the dividing line, wherein the relative position of the center of the lane and the dividing line includes that the center of the lane is on the dividing line, the center of the lane is on the left side of the dividing line, or the center of the lane is on the right side of the dividing line. The relative position of the center of the lane and the dividing line is the relative position of the center of the road image and the center of the lane, that is, the relative position of the intelligent transportation vehicle in the lane and the center of the lane.

[0088] In an optional embodiment, the motor rotating speeds of the left and right sides of the intelligent transportation vehicle are determined according to the relative position relationship between the lane center and the dividing line to control the steering of the intelligent transportation vehicle, including: if the lane center is located on the left side of the dividing line, the motor rotating speed of the left side of the intelligent transportation vehicle is determined as a first rotating speed, and the motor rotating speed of the right side of the intelligent transportation vehicle is determined as a second rotating speed to control the intelligent transportation vehicle to steer to the left; if the lane center is located on the right side of the dividing line, the motor rotating speed of the left side of the intelligent transportation vehicle is determined as the second rotating speed, and the motor rotating speed of the right side of the intelligent transportation vehicle is determined as the first rotating speed to control the intelligent transportation vehicle to steer to the right; wherein the first rotating speed is greater than the second rotating speed; and the first rotating speed is the motor rotating speed corresponding to the steering speed.

[0089] If the lane center is located on the left side of the dividing line, it indicates that the intelligent transportation vehicle is currently close to the left lane line, and the intelligent transportation vehicle is controlled to drive to the right to ensure that the intelligent transportation vehicle does not deviate from the predetermined lane. Specifically, the motor rotating speed of the left side of the intelligent transportation vehicle is determined as a first rotating speed, and the motor rotating speed of the right side of the intelligent transportation vehicle is determined as a second rotating speed. The first rotating speed is greater than the second rotating speed, the wheel speed of the left drive wheel of the intelligent transportation vehicle is greater than the wheel speed of the right drive wheel, the intelligent transportation vehicle drives to the right, and approaches the lane center.

[0090] Correspondingly, if the lane center is located on the right side of the dividing line, it indicates that the intelligent transportation vehicle is currently close to the right lane line, and the intelligent transportation vehicle is controlled to drive to the left to ensure that the intelligent transportation vehicle does not deviate from the predetermined lane. Specifically, the motor rotating speed of the right side of the intelligent transportation vehicle is determined as a first rotating speed, and the motor rotating speed of the left side of the intelligent transportation vehicle is determined as a second rotating speed. The first rotating speed is greater than the second rotating speed, the wheel speed of the right drive wheel of the intelligent transportation vehicle is greater than the wheel speed of the left drive wheel, the intelligent transportation vehicle drives to the left, and approaches the lane center.

[0091] For example, the first rotating speed is the motor rotating speed corresponding to the steering speed, and the PWM frequency corresponding to the first rotating speed is denoted as P t The second rotating speed can be represented as P t -m×S i , wherein S i represents the horizontal distance between the center lane center of the road image. m represents a frequency scaling coefficient between 0 and 1, which is an empirical value determined by a technician according to actual conditions.

[0092] S460, otherwise, a route deviation warning is generated and the intelligent transportation vehicle is controlled to stop.

[0093] If the absolute value of the horizontal distance is greater than the preset steering reference value, it indicates that the intelligent transportation vehicle has deviated from the predetermined lane, and if the intelligent transportation vehicle continues to travel, danger may occur, at which time the intelligent transportation vehicle needs to be controlled to stop, and a route deviation warning is generated and sent to the user for the user to take over the intelligent transportation vehicle in time.

[0094] In an optional embodiment, a top-left corner vertex of a road image can be taken as an origin, and a horizontal direction and a vertical direction of the road image can be taken as an x-axis and a y-axis direction respectively to construct a road image coordinate system. A center of the road image and a lane center are represented respectively in the image coordinate system. A difference value in the horizontal direction between the center of the road image and the lane center is calculated according to coordinate values of the center of the road image and the lane center. The travel direction of the intelligent transportation vehicle is determined according to the positive and negative and the value of the difference value.

[0095] The embodiment of the present application determines the positional relationship between the intelligent transportation vehicle and the predetermined lane by calculating the horizontal distance between the center of the road image and the lane center, and determines the travel direction of the intelligent transportation vehicle according to the relative position of the center of the road image and the lane center when the absolute value of the horizontal distance is less than or equal to the preset steering reference value, and generates a route deviation warning and controls the intelligent transportation vehicle to stop when the absolute value of the horizontal distance is greater than the preset steering reference value. The embodiment of the present application can timely adjust the travel direction of the intelligent transportation vehicle according to the positional relationship between the intelligent transportation vehicle and the predetermined lane, and avoid the intelligent transportation vehicle from deviating from the lane. In addition, the embodiment of the present application can early discover the situation that the intelligent transportation vehicle deviates from the predetermined lane by comparing the horizontal distance between the center of the road image and the lane center with the preset steering reference value, and generates a route deviation warning and controls the intelligent transportation vehicle to stop when the intelligent transportation vehicle deviates from the predetermined lane, thereby reducing the probability of safety accidents.

[0096] Embodiment Five

[0097] Figure 5 The device is a steering speed control device for an intelligent transportation vehicle provided by the embodiment of the present application. The device can be applied to control the steering speed of the intelligent transportation vehicle when the intelligent transportation vehicle is steering, and ensure that the intelligent transportation vehicle steers stably. The device can be realized by software and / or hardware, and can be integrated into an electronic device such as an intelligent terminal.

[0098] As shown in Figure 5 the device can include a safe speed adjusting road region determination module 510, a lane line curvature calculation module 520, and an intelligent transportation vehicle travel direction and steering speed determination module 530.

[0099] The safe speed adjusting road region determination module 510 is configured to select a safe speed adjusting road region from a road image in which the intelligent transportation vehicle is located according to a current speed of the intelligent transportation vehicle.

[0100] The lane line curvature calculation module 520 is configured to calculate a lane line curvature of the safe speed regulation road region.

[0101] The intelligent transport vehicle traveling direction and turning speed determination module 530 is configured to determine a traveling direction and a turning speed of the intelligent transport vehicle according to the lane line curvature.

[0102] The technical scheme provided in the embodiments of the present application selects a safe speed regulation road region from a road image in which the intelligent transport vehicle is located according to a current speed of the intelligent transport vehicle, calculates a lane line curvature of the safe speed regulation road region, and determines a traveling direction and a turning speed of the intelligent transport vehicle according to the lane line curvature. The safe speed regulation road region provides sufficient buffer distance for the intelligent transport vehicle to adjust the current speed to a speed suitable for turning, and smooth speed regulation is achieved. The embodiments of the present application also accurately determine the traveling direction and the turning speed of the intelligent transport vehicle according to the lane line curvature, which ensures the turning stability of the intelligent transport vehicle while taking into account the transport speed.

[0103] Optionally, the lane line curvature calculation module 520 includes a safe speed regulation road region segmentation sub-module configured to segment lane lines in the safe speed regulation road region to obtain at least two lane line sub-regions, a candidate lane line curvature determination sub-module configured to calculate curvatures of the lane lines in each lane line sub-region as candidate lane line curvatures, and a lane line curvature determination sub-module configured to select the lane line curvature of the safe speed regulation road region from the at least two candidate lane line curvatures.

[0104] Optionally, the intelligent transport vehicle traveling direction and turning speed determination module 530 includes an intelligent transport vehicle traveling direction determination sub-module and an intelligent transport vehicle turning speed determination sub-module. The intelligent transport vehicle traveling direction determination sub-module is specifically configured to determine the traveling direction of the intelligent transport vehicle according to the lane line curvature. The intelligent transport vehicle turning speed determination sub-module is specifically configured to determine the turning speed of the intelligent transport vehicle according to the lane line curvature.

[0105] The intelligent transport vehicle turning speed determination sub-module includes a maximum turning speed determination unit configured to determine a maximum turning speed of the intelligent transport vehicle according to the lane line curvature, a road surface friction coefficient, and a vehicle body weight, and a safe turning speed determination unit configured to determine a safe turning speed of the intelligent transport vehicle according to the maximum turning speed and a preset safety speed coefficient, as the turning speed of the intelligent transport vehicle.

[0106] Optionally, the intelligent transport vehicle running direction determining sub-module comprises: a curvature maximum position determining unit, configured to determine a curvature maximum position in the road image according to the lane line curvature; wherein the road image comprises at least two parallel lane lines; a lane center determining unit, configured to determine a midpoint of a horizontal line between two adjacent lane lines as a lane center at the curvature maximum position; wherein a straight line determined by the lane center and the maximum curvature position is parallel to a horizontal boundary of the road image; and a running direction determining unit, configured to determine a running direction of the intelligent transport vehicle according to a center of the road image, the lane center and a preset steering reference value.

[0107] Optionally, the running direction determining unit comprises: a running direction determining first sub-unit, configured to calculate a horizontal distance between the center of the road image and the lane center, and determine the running direction of the intelligent transport vehicle according to relative positions of the center of the road image and the lane center if an absolute value of the horizontal distance is less than or equal to the preset steering reference value; and a running direction determining second sub-unit, configured to generate a route deviation warning and control the intelligent transport vehicle to stop if not.

[0108] Optionally, the running direction determining first sub-unit comprises: a split line determining sub-unit, configured to determine a straight line passing through the center of the road image and parallel to a vertical boundary of the road image as a split line; and a motor speed determining sub-unit, configured to determine motor speeds of left and right sides of the intelligent transport vehicle according to relative positions of the lane center and the split line, so as to control the intelligent transport vehicle to steer.

[0109] Optionally, the motor speed determining sub-unit comprises: a motor speed determining first sub-unit, configured to determine a left motor speed of the intelligent transport vehicle as a first speed and a right motor speed of the intelligent transport vehicle as a second speed if the lane center is located on a left side of the split line, so as to control the intelligent transport vehicle to steer left; and a motor speed determining second sub-unit, configured to determine the left motor speed of the intelligent transport vehicle as the second speed and the right motor speed of the intelligent transport vehicle as the first speed if the lane center is located on a right side of the split line, so as to control the intelligent transport vehicle to steer right; wherein the first speed is greater than the second speed; and the first speed is a motor speed corresponding to the steering speed.

[0110] The intelligent transport vehicle steering speed control device provided by the embodiment of the present application can execute the intelligent transport vehicle steering speed control method provided by any embodiment of the present application, and has the corresponding performance modules and beneficial effects of executing the intelligent transport vehicle steering speed control method.

[0111] Embodiment six

[0112] The embodiment six of the present application further provides a storage medium containing computer executable instructions, which are used for executing an intelligent transport vehicle steering speed control method when executed by a computer processor, and the method comprises the following steps of:

[0113] selecting a safe speed regulation road area from a road image of a road where the intelligent transport vehicle is located according to a current speed of the intelligent transport vehicle;

[0114] calculating a lane line curvature of the safe speed regulation road area;

[0115] determining a traveling direction and a steering speed of the intelligent transport vehicle according to the lane line curvature.

[0116] The storage medium refers to any various types of memory electronic devices or storage electronic devices. The term "storage medium" is intended to include an installation medium, such as a CD-ROM, a floppy disk, or a tape device; a computer system memory or random access memory, such as a DRAM, a DDR RAM, a SRAM, an EDO RAM, a Rambus RAM, and the like; a non-volatile memory, such as a flash memory, a magnetic medium (for example, a hard disk or a floppy disk), or an optical medium (for example, a CD-ROM); a register or other similar types of memory elements, and the like. The storage medium can further include other types of memories or combinations thereof. In addition, the storage medium can be located in the computer system where the program is executed, or can be located in a different second computer system which is connected to the computer system through a network, such as the Internet. The second computer system can provide the program instructions to the computer for execution. The term "storage medium" can include two or more storage media which can reside in different unknowns (for example, in different computer systems connected through a network). The storage medium can store program instructions (for example, specifically implemented as a computer program) which can be executed by one or more processors.

[0117] Of course, the storage medium containing computer executable instructions provided by the embodiment of the present application is not limited to the intelligent transport vehicle steering speed control operation as described above, and can also execute the related operations in the intelligent transport vehicle steering speed control method provided by any embodiment of the present application.

[0118] Embodiment seven

[0119] The embodiment seven of the present application provides an electronic device, and the intelligent transport vehicle steering speed control device provided by the embodiment of the present application can be integrated in the electronic device. The electronic device can be a device configured in a system, or a device performing part or all of the performance in the system. Figure 6 is a structural schematic diagram of an electronic device provided by the embodiment seven of the present application. As shown in Figure 6As shown, the embodiment provides an electronic device 600, which includes: one or more processors 620; a storage device 610, configured to store one or more programs, when the one or more programs are executed by the one or more processors 620, so that the one or more processors 620 implement the intelligent transport vehicle steering speed control method provided by the embodiments of the present application, the method includes:

[0120] Obtaining a visual recognition result obtained by visual recognition of the target object by the image collector, and obtaining an auxiliary recognition result obtained by recognition of the target object by the auxiliary detection device;

[0121] If the difference between the visual recognition result and the auxiliary recognition result exceeds a set threshold, determining the performance of the image collector according to the visual recognition result and the recognition range of the image collector.

[0122] Of course, those skilled in the art can understand that the processor 620 also implements the technical solutions of the intelligent transport vehicle steering speed control method provided by any embodiment of the present application.

[0123] Figure 6 The electronic device 600 shown is only an example and should not limit the performance and use range of the embodiments of the present application.

[0124] As Figure 6 shown, the electronic device 600 includes a processor 620, a storage device 610, an input device 630 and an output device 640; the number of processors 620 in the electronic device can be one or more, Figure 6 one processor 620 is taken as an example; the processor 620, the storage device 610, the input device 630 and the output device 640 in the electronic device can be connected through a bus or other means, Figure 6 for example, connected through the bus 650.

[0125] The storage device 610 as a kind of computer readable storage medium, it can be used to store software program, computer executable program and module unit, such as the program instruction corresponding to the intelligent transport vehicle steering speed control method in the embodiments of the present application.

[0126] The storage 610 can include a program storage area that can store an operating system, at least one application program required for performance, and a data storage area that can store data created according to use of the terminal, etc. In addition, the storage 610 can include a high-speed random access memory, and can further include a non-volatile memory such as at least one of a magnetic disk storage device, a flash memory device, or other non-volatile solid state memory device. In some examples, the storage 610 can further include a memory disposed remotely with respect to the processor 620, and these remote memories can be connected through a network. Examples of the network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0127] The input device 630 can be used to receive inputted digital, character information or voice information, and to generate key signal input related to user settings and performance control of the electronic device. The output device 640 can include a display screen, a speaker, etc. of the electronic device.

[0128] The intelligent transport vehicle steering speed control device, medium and electronic device provided in the above embodiments can execute the intelligent transport vehicle steering speed control method provided in any embodiment of the present application, and have the corresponding performance modules and beneficial effects of executing the method. Technical details not described in detail in the above embodiments can be referred to the intelligent transport vehicle steering speed control method provided in any embodiment of the present application.

[0129] Note that the above are only preferred embodiments of the present application and the technical principles applied. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and those skilled in the art can make various obvious changes, re-adjustments and substitutions without departing from the scope of the present application. Therefore, although the present application has been described in more detail through the above embodiments, the present application is not limited to the above embodiments, and can include more other equivalent embodiments without departing from the concept of the present application, and the scope of the present application is determined by the scope of the appended claims.

Claims

1. A method for controlling the steering speed of an intelligent transport vehicle, characterized by, The method comprises: According to the current speed of the intelligent transport vehicle, a safe speed regulation road area is selected from the road image where the intelligent transport vehicle is located; The curvature of the lane line of the safe speed regulation road area is calculated; According to the curvature of the lane line, the direction of travel and the steering speed of the intelligent transport vehicle are determined; The curvature of the lane line of the safe speed regulation road area is calculated, comprising: The lane line in the safe speed regulation road area is divided to obtain at least two lane line sub-areas; wherein the lane line sub-areas are obtained by equally dividing the lane line in the safe speed regulation road area along a direction parallel to the vertical boundary of the road image; The curvature of the lane line in each lane line sub-area is calculated as a candidate lane line curvature; The curvature of the lane line of the safe speed regulation road area is selected from at least two candidate lane line curvatures.

2. The method of claim 1, wherein, According to the curvature of the lane line, the steering speed of the intelligent transport vehicle is determined, comprising: According to the curvature of the lane line, the road surface friction coefficient and the weight of the vehicle body, the maximum steering speed of the intelligent transport vehicle is determined; According to the maximum steering speed and a preset safety speed coefficient, the safe steering speed of the intelligent transport vehicle is determined as the steering speed of the intelligent transport vehicle.

3. The method of claim 1, wherein, According to the curvature of the lane line, the direction of travel of the intelligent transport vehicle is determined, comprising: According to the curvature of the lane line, the position of maximum curvature in the road image is determined; wherein the road image includes at least two parallel lane lines; According to the position of maximum curvature, the midpoint of the horizontal line between the two adjacent lane lines is determined as the lane center; wherein the straight line determined by the lane center and the position of maximum curvature is parallel to the horizontal boundary of the road image; According to the center of the road image, the lane center and a preset steering reference value, the direction of travel of the intelligent transport vehicle is determined.

4. The method of claim 3, wherein, According to the center of the road image, the lane center and a preset steering reference value, the direction of travel of the intelligent transport vehicle is determined, comprising: The horizontal distance between the center of the road image and the lane center is calculated, and if the absolute value of the horizontal distance is less than or equal to the preset steering reference value, the direction of travel of the intelligent transport vehicle is determined according to the relative position of the center of the road image and the lane center; Otherwise, a route deviation warning is generated and the intelligent transport vehicle is controlled to stop.

5. The method of claim 4, wherein, According to the relative position of the center of the road image and the lane center, the direction of travel of the intelligent transport vehicle is determined, comprising: A straight line passing through the center of the road image and parallel to the vertical boundary of the road image is taken as a dividing line; According to the relative position relationship between the lane center and the dividing line, the motor speeds of the left and right sides of the intelligent transport vehicle are determined to control the steering of the intelligent transport vehicle.

6. The method of claim 5, wherein, According to the relative position relationship between the lane center and the dividing line, the motor speeds of the left and right sides of the intelligent transport vehicle are determined to control the steering of the intelligent transport vehicle, comprising: If the lane center is located on the left side of the split line, the left motor speed of the intelligent transportation vehicle is determined as a first speed, and the right motor speed of the intelligent transportation vehicle is determined as a second speed, so as to control the intelligent transportation vehicle to turn left; If the lane center is located on the right side of the split line, the left motor speed of the intelligent transportation vehicle is determined as the second speed, and the right motor speed of the intelligent transportation vehicle is determined as the first speed, so as to control the intelligent transportation vehicle to turn right; wherein the first speed is greater than the second speed; the first speed is the motor speed corresponding to the turning speed.

7. An intelligent transport vehicle steering speed control apparatus characterized by comprising: The device comprises: A safe speed regulation road region determination module configured to select a safe speed regulation road region from a road image in which the intelligent transportation vehicle is located according to a current speed of the intelligent transportation vehicle; A lane line curvature calculation module configured to calculate a lane line curvature of the safe speed regulation road region; An intelligent transportation vehicle travel direction and turning speed determination module configured to determine a travel direction and a turning speed of the intelligent transportation vehicle according to the lane line curvature; The lane line curvature calculation module comprises a safe speed regulation road region segmentation sub-module, a candidate lane line curvature determination sub-module, and a lane line curvature determination sub-module; The safe speed regulation road region segmentation sub-module is configured to segment lane lines in the safe speed regulation road region to obtain at least two lane line sub-regions; wherein the lane line sub-regions are obtained by equally segmenting the lane lines in the safe speed regulation road region along a direction parallel to a vertical boundary of the road image; The candidate lane line curvature determination sub-module is configured to calculate curvatures of the lane lines in each lane line sub-region as candidate lane line curvatures, respectively; The lane line curvature determination sub-module is configured to select a lane line curvature of the safe speed regulation road region from the at least two candidate lane line curvatures.

8. A computer-readable storage medium having stored thereon a computer program, characterized in that, The program is executed by the processor to implement the intelligent transportation vehicle turning speed control method of any one of claims 1-6.

9. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the computer program to implement the intelligent transportation vehicle turning speed control method of any one of claims 1-6.

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