A method for controlling automatic loading of a vehicle using point cloud slope

Abstract

The application provides a method for controlling automatic loading of a vehicle using a point cloud slope, which comprises the following steps: determining whether an incoming vehicle is a loading vehicle according to point cloud data of the incoming vehicle identified by a laser radar; determining whether a minimum difference between an x coordinate of a front baffle of a vehicle compartment and an x coordinate of a discharge port is greater than a set threshold value and whether a vehicle compartment skew angle is less than or equal to a preset threshold value when the loading vehicle is parked; controlling discharge of the discharge port according to a preset loading time; obtaining a Y direction material slope and an X direction material slope; determining whether the Y direction material slope reaches a maximum slope and whether the X direction material slope reaches a maximum slope; then the front side of the loading vehicle compartment reaches a preset loading requirement; loading the middle side of the loading vehicle compartment and the rear side of the loading vehicle compartment according to the loading time or the material amount; after loading is completed, prompting a driver to drive away; and through real-time measurement of a material level, the real-time state of vehicle loading is timely controlled, and problems such as bulk material are avoided.

Description

Technical Field

[0001] This invention relates to the field of unmanned vehicle loading technology, specifically a method for automatically loading vehicles using point cloud slope control. Background Technology

[0002] In the field of automated loading of bulk materials onto trucks, there are several intractable problems:

[0003] Material height monitoring equipment during loading, such as ultrasonic radar and lidar, is easily affected by dust suppression and material flow disturbances. This means that monitoring equipment installed near the discharge port struggles to reliably obtain accurate real-time material level information. Conversely, if the equipment is moved far from the discharge port, the real-time data often differs significantly from the discharge port height, rendering the data meaningless. Furthermore, the tie rods or ropes often installed inside truck beds to secure the side panels can interfere with the material level determination by monitoring equipment, and these devices are difficult to completely shield using conventional methods.

[0004] Furthermore, automated loading systems for automobiles often lack precise vehicle location information. Both the vehicle's deviation and forward distance are controlled by the driver, making it difficult for conventional control methods to predict accurate loading information. If a vehicle deviates or fails to travel the required distance, a single monitoring device near the discharge port is insufficient for timely and effective adjustments, potentially leading to unexpected situations. Adding more monitoring equipment, however, increases production costs and system complexity. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for controlling automatic vehicle loading using point cloud slope, which helps solve the problems of automatic vehicle loading systems being unable to accurately grasp vehicle location information and the susceptibility of material monitoring equipment to interference during loading.

[0006] To achieve the above objectives, the present invention provides a method for controlling automatic vehicle loading using point cloud slope, comprising the following steps:

[0007] The system uses a lidar unit installed on one side of the carriage to identify point cloud data of the vehicles entering the carriage and to determine whether the vehicle is the loading vehicle.

[0008] If so, when the loading vehicle stops, determine whether the minimum difference between the x-coordinate of the front baffle of the truck bed and the x-coordinate of the unloading port is greater than the set threshold, and whether the tilt angle of the truck bed is less than or equal to the preset threshold.

[0009] If so, the discharge from the feeding port is controlled according to the preset filling time;

[0010] Obtain point cloud data of the loading compartment, and obtain the material slope in the Y direction and the material slope in the X direction based on the point cloud data of the front side of the loading compartment;

[0011] Determine whether the material slope in the Y direction has reached its maximum slope, and whether the material slope in the X direction has reached its maximum slope.

[0012] If so, the front of the loading compartment meets the preset loading requirements;

[0013] Calculate the loading time or material quantity required for the front of the loading compartment to reach the preset loading requirements;

[0014] Loading is carried out on the middle and rear sides of the loading compartment according to the loading time or the amount of material;

[0015] Once loading is complete, instruct the driver to leave.

[0016] By adopting the above technical solution, material point cloud data is acquired through LiDAR, and then the point cloud slope is used to control the automatic loading method. The maximum slope value in the X direction, the maximum slope value in the Y direction, and the maximum height in the Y direction can be used to realize the real-time measurement of material level. Based on this, the threshold of the material level height at the discharge port and the vehicle baffle can also be calculated. It can even estimate the volume of loaded material in a better way, so as to control the real-time status of vehicle loading in a timely manner and avoid problems such as material spillage.

[0017] Optionally, the offset angle of the carriage is calculated using point cloud data of the carriage and point cloud data of the carriage's standard parking position.

[0018] Optionally, the preset filling time is set by the actual on-site environment. The filling time of the first pile of material is observed by auxiliary tools or by manpower, and the parameters are set accordingly.

[0019] Optionally, the height of the material is lower than the height of the carriage baffle minus a difference, the difference being determined by the type of material being filled.

[0020] Optionally, when the slope is abnormal, the maximum slope of the material in the Y direction and the maximum slope of the material in the X direction can be obtained by changing the point cloud sampling range to avoid the obstruction at the discharge port.

[0021] Optionally, the vehicle travel distance is obtained by acquiring the point cloud coordinates of the rear panel of the cargo compartment before and after the vehicle moves.

[0022] Optionally, the formula for calculating the slope in the Y direction is: ky=(z1-z2) / (y1-y2), and the formula for calculating the slope in the Y direction is: kx=(z1-z2) / (x1-x2), where (y1, z1) and (y2, z2) are the coordinates of two points on the straight line with the largest slope perpendicular to the carriage, and (x1, z1) and (x2, z2) are the coordinates of two points on the straight line with the largest slope parallel to the carriage.

[0023] This invention provides a method for controlling automatic vehicle loading using point cloud slope, which has the following beneficial effects:

[0024] This invention provides a method for controlling automatic loading of vehicles using point cloud slope. This method can realize real-time measurement of material level, and can also calculate the threshold of the material level height at the discharge port and the vehicle baffle. It can even estimate the volume of loaded material in a better way, so as to control the real-time status of vehicle loading in a timely manner and avoid problems such as material spillage. Attached Figure Description

[0025] Figure 1 This is a flowchart illustrating a method for controlling automatic vehicle loading using point cloud slope, as shown in an embodiment of the present invention.

[0026] Figure 2 This is a schematic diagram of the Y-direction installation of a method for controlling automatic vehicle loading using point cloud slope, as shown in an embodiment of the present invention.

[0027] Figure 3 This is a schematic diagram of the X-direction installation of a method for controlling automatic vehicle loading using point cloud slope, as shown in an embodiment of the present invention. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are one embodiment of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] like Figure 1 As shown, this embodiment of the invention provides a method for controlling automatic vehicle loading using point cloud slope, comprising:

[0030] The system uses a lidar sensor installed on one side of the vehicle to identify the point cloud data of the entering vehicle and determine whether the entering vehicle is the loading vehicle. It also uses methods such as 3D model matching technology or vehicle number recognition technology to determine whether it is the loading vehicle. 3D model matching is to match the 3D model with the 3D point cloud data of the vehicle.

[0031] If so, when the loaded vehicle stops, it is determined whether the minimum difference between the x-coordinate of the front baffle of the truck bed and the x-coordinate of the discharge port is greater than a set threshold, and whether the truck bed tilt angle is less than or equal to a preset threshold. The truck bed offset angle is calculated using the point cloud data of the truck bed and the point cloud data of the standard parking position of the truck bed. The conditions for the vehicle to meet the parking conditions also include: the radar point cloud collected by the lidar includes the complete point cloud of the highest material position in the Y direction directly opposite and the highest point of the truck bed baffle; the radar point cloud collected by the lidar includes the clear material radar point cloud outside the interference zone on both sides of the discharge port in the direction of vehicle travel; and the distance of the clear material radar point cloud outside the interference zone on both sides from the discharge port is greater than or equal to 30cm. The vehicle must be stationary for more than or equal to 10s.

[0032] If so, the discharge from the discharge port is controlled according to the preset filling time; the preset filling time is set by the actual on-site environment, and the filling time of the first pile of material is observed by auxiliary tools or manual observation, and the parameters are set accordingly.

[0033] The filling time is determined by the specific configuration on site and the height of the carriage. If the height of the carriage changes, the volume change ratio can be calculated based on the height and width of the carriage, and the filling time can be fine-tuned.

[0034] Obtain point cloud data of the loading compartment, and obtain the material slope in the Y direction and the material slope in the X direction based on the point cloud data of the front side of the loading compartment;

[0035] Determine whether the material slope in the Y direction has reached its maximum slope, and whether the material slope in the X direction has reached its maximum slope. The material point cloud on the right side of the feed inlet forms a hilly structure. Among these hilly structures, the structure with the highest height has the maximum slope in the Y direction, which is the smallest tangential angle. At this time, it must correspond to a tilt angle in the horizontal direction, which is the maximum slope of the material in the X direction. The formula for calculating the slope in the Y direction is: ky=(z1-z2) / (y1-y2). The formula for calculating the slope in the Y direction is: kx=(z1-z2) / (x1-x2). Where (y1, z1) and (y2, z2) are the coordinates of two points on the straight line with the maximum slope perpendicular to the carriage, and (x1, z1) and (x2, z2) are the coordinates of two points on the straight line with the maximum slope parallel to the carriage.

[0036] If so, the front of the loading compartment meets the preset loading requirements; specifically, the material height is lower than the height of the compartment side panel minus a certain difference, which is determined by the type of material being loaded. A hazardous material height is set on the compartment side panel, which is equal to the height of the compartment side panel minus a fixed value. The fixed value is set according to the material and its descent speed. For example, coal mines discharge material relatively quickly, so the fixed value is set larger; grain discharges material relatively slowly, so the value is set smaller. The difference is generally less than 5cm. Loading in place means that the height of the material piled at the compartment side panel is less than the height of the hazardous material, but not lower than the height of the hazardous material minus the difference. The specific standard is calculated based on the difference in the loading volume. If the loading is not in place, the loading time is increased, for example, by 1 second.

[0037] Calculate the loading time or material quantity required to reach the preset loading requirements at the front of the loading compartment; when the slope is abnormal, change the point cloud sampling range to avoid the obstruction at the discharge port, and obtain the maximum slope of the material in the Y direction and the maximum slope of the material in the X direction.

[0038] If an abnormal slope is encountered during slope calculation, such as a sudden increase in slope or exceeding the maximum slope, the reinforcing ribs can be avoided by changing the point cloud sampling range. If the slope calculation encounters an abnormal situation, there may be obstructions, such as reinforcing ribs, interfering with the point cloud slope calculation. In this case, the reinforcing ribs can be avoided by changing the point cloud sampling range, or the reinforcing rib target can be removed by using a point cloud filtering algorithm.

[0039] Loading is carried out on the middle and rear sides of the loading compartment according to the loading time or the amount of material;

[0040] Once loading is complete, instruct the driver to leave.

[0041] In addition, the vehicle's travel distance is obtained by acquiring the point cloud coordinates of the rear panel of the cargo box before and after the vehicle moves. By measuring the changes in the slope and height of the point cloud, the vehicle's travel distance can also be calculated. If the travel distance is too short, the driver can be reminded to continue picking up the vehicle.

[0042] An electric valve is installed at the discharge port. The electric valve is controlled by an electric valve remote control system. The lidar is connected to a computer, and the lidar and the computer are connected via a remote network. The electric valve remote control system is existing technology.

[0043] The implementation principle of this invention is as follows: In this solution, a lidar device is required and installed on the side of the vehicle in the direction of travel. The installation height of the lidar should be higher than the height of the highest compartment baffle. The lidar detects a point cloud. First, the maximum slope of the material in the Y direction is calculated from the point cloud data. The calculation formula is: ky=(z1-z2) / (y1-y2). Therefore, by backtracking the spatiotemporal point cloud, that is, finding the slope of the point cloud in the horizontal direction when the discharge port is directly above the point cloud with the maximum slope, the maximum slope value of the material in the X direction corresponding to the horizontal direction can be calculated. The calculation formula for the maximum slope of the material in the X direction is: kx=(z1-z2) / (x1-x2). With this value, it is possible to estimate when the material reaches the maximum height during the subsequent loading process. Finally, the height in the Y direction is calculated based on the distance between the discharge port and the front baffle of the compartment and the slope in the Y direction. The height in the Y direction is then compared with the height of the hazardous material. The loading status of the material is determined by the maximum slope value in the X direction, the maximum slope value in the Y direction, and the maximum height in the Y direction.

[0044] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for controlling automatic vehicle loading using point cloud slope, characterized in that, include: The system uses a lidar unit installed on one side of the carriage to identify point cloud data of the vehicles entering the carriage and to determine whether the vehicle is the loading vehicle. If so, when the loading vehicle stops, determine whether the minimum difference between the x-coordinate of the front baffle of the truck bed and the x-coordinate of the unloading port is greater than the set threshold, and whether the tilt angle of the truck bed is less than or equal to the preset threshold. If so, the discharge from the feeding port is controlled according to the preset filling time; The point cloud data of the loading compartment is acquired, and the material slope in the Y direction and the material slope in the X direction are obtained based on the point cloud data of the front side of the loading compartment. The formula for calculating the slope in the Y direction is: ky=(z1-z2) / (y1-y2), and the formula for calculating the slope in the X direction is: kx=(z1-z2) / (x1-x2), where (y1, z1) and (y2, z2) are the coordinates of two points on the straight line with the largest slope perpendicular to the compartment, and (x1, z1) and (x2, z2) are the coordinates of two points on the straight line with the largest slope parallel to the compartment. Determine whether the material slope in the Y direction has reached its maximum slope, and whether the material slope in the X direction has reached its maximum slope. If so, the front of the loading compartment meets the preset loading requirements; Calculate the loading time or material quantity required for the front of the loading compartment to reach the preset loading requirements; Loading is carried out on the middle and rear sides of the loading compartment according to the loading time or the amount of material; Once loading is complete, instruct the driver to leave.

2. The method for controlling automatic vehicle loading using point cloud slope according to claim 1, characterized in that, The offset angle of the carriage is calculated using point cloud data of the carriage and point cloud data of the carriage's standard parking position.

3. The method for controlling automatic vehicle loading using point cloud slope according to claim 1, characterized in that, The preset filling time is set according to the actual on-site environment. The filling time of the first pile of material is observed by auxiliary tools or by manpower, and the parameters are set accordingly.

4. The method for controlling automatic vehicle loading using point cloud slope according to claim 1, characterized in that, The height of the material is lower than the height of the carriage baffle minus a difference, the difference being determined by the type of material being loaded.

5. A method for controlling automatic vehicle loading using point cloud slope according to claim 1, characterized in that, When the slope is abnormal, the maximum slope of the material in the Y direction and the maximum slope of the material in the X direction are obtained by changing the point cloud sampling range to avoid the obstruction at the discharge port.

6. The method for controlling automatic vehicle loading using point cloud slope according to claim 1, characterized in that, The distance traveled by the vehicle was obtained by acquiring the point cloud coordinates of the rear panel of the vehicle before and after the vehicle moved.

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