A process control based road detection system and method

Abstract

The application discloses a road detection system and method based on process control, which comprises a paving variable automatic leveling algorithm and a final-pressing road roller online flatness detection technology. The technology and method realize the final road surface flatness after compaction by carrying out inverse paving after carrying out grid processing on the road surface and calculating the average height of the road surface in each grid. In the final-pressing process, the road surface fluctuation and flatness are more accurately measured by using multi-line laser and positioning technology, and relevant information is displayed in real time, so that the operator can operate the road roller conveniently. The application has the beneficial effects of improving the efficiency and construction quality of road construction, reducing the operation difficulty and labor intensity of the operator, and realizing intelligent and automatic control.

Description

Technical Field

[0001] This invention relates to a road inspection system and method based on process control, belonging to the field of intelligent application technology of engineering machinery. Background Technology

[0002] Existing road paving and leveling technologies mainly employ two methods: manual benchmarks and virtual benchmarks. Manual benchmarks are established by setting up steel cables, and then a leveling beam is used to slide along the cables for paving. Virtual benchmarks utilize millimeter-wave radar to measure the average elevation of three locations and use this as the paving benchmark. However, both methods can only ensure a smooth surface after paving, not after compaction. Therefore, an automatic paving leveling algorithm is needed to address this issue.

[0003] Furthermore, the unevenness that occurs during final compaction is mainly due to road surface bulges. During the day, people can usually identify road surface unevenness by sight, but it is often difficult to detect during nighttime construction. Current asphalt and water-stabilized pavement compaction processes use a method of compaction before testing. Once the road surface smoothness test fails, with the passage of time and the drop in temperature, it becomes difficult for the road roller to smooth out the uneven road surface. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a road inspection system and method based on process control, which solves the problem of the inability to automatically level the road during the paving process in existing technologies.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A process-controlled road detection system includes a paver, a roller, a multi-line laser, an on-board processor, a positioning base station, and an on-board positioning mobile station;

[0007] A paver is used to spread road construction materials evenly and smoothly.

[0008] A road roller is used to compact the road surface laid by a paver.

[0009] Multi-line lasers are used to measure the distance from multiple target points on a plane to the laser mounting point.

[0010] The positioning base station, based on real-time dynamic differential positioning technology, is used to receive satellite positioning signals, provide reference points for vehicle-mounted positioning mobile stations, and transmit positioning signals to vehicle-mounted positioning mobile stations.

[0011] A vehicle-mounted positioning mobile station is used to receive signals from a positioning base station to determine the location of the vehicle on which the positioning device is installed.

[0012] The vehicle-mounted processor is used to receive measurement data from multi-line lasers and vehicle-mounted positioning mobile stations, process the data, and output the predetermined paving thickness.

[0013] A road detection method based on process control includes the following steps:

[0014] During the paving process, the construction area is scanned in real time, and the road surface within the scanned area is divided into several grids of the same size;

[0015] Determine the height and position of each grid cell;

[0016] The paving thickness is determined based on the grid height, and the screed is controlled to reach the grid position for reverse paving.

[0017] Furthermore, the aforementioned steps for determining the grid height include:

[0018] The height h of each grid in the scanning area is calculated as follows: h = h_laser - bsin(α), where α is the angle between the multi-line laser corresponding to the center point of the grid and the horizontal, b is the distance from the center point N of the grid measured by the laser on the paver to the multi-line laser, and h_laser is the height from the installation position of the multi-line laser on the paver to the plane where the paver track is located.

[0019] Furthermore, the formula for calculating each grid position is as follows:

[0020]

[0021]

[0022] In the formula, (N) x N y Let (x0, y0) be the positioning coordinates of the grid center point N, (x1, y1) be the position coordinates of the two vehicle-mounted positioning mobile stations on the paver, l be the length of the line connecting the left laser on the paver to the two vehicle-mounted positioning mobile stations, a be the lateral distance from the left laser on the paver to (x0, y0), b be the distance from the multi-line laser on the paver to the grid center point N, δ be the scattering angle, and α be the angle between the multi-line laser corresponding to the grid center point N and the horizontal.

[0023] Furthermore, the aforementioned steps for determining the paving thickness based on grid height include:

[0024] Based on the height of each grid cell, the average height of the grid cells in the same column is calculated, and the calculated average height is recorded as the height h0 of the road surface in that column relative to the plane where the paver track is located.

[0025] Calculate the paving thickness:

[0026] h tp =h0+(hset -h0)·k sp

[0027] In the formula, h tp For paving thickness, h set k is the preset thickness of the paved surface after compaction. sp This is the loose paving coefficient.

[0028] Furthermore, after the aforementioned reverse paving is completed, the following steps are also included:

[0029] During the final compaction process, the construction area is re-scanned, and the road surface within the scanned area is divided into several grids of the same size;

[0030] Determine the flatness and location of each grid cell;

[0031] Control the road roller to reach the grid position and start vibration based on the flatness.

[0032] Furthermore, the formula for calculating the flatness σ of each grid cell is as follows:

[0033]

[0034] In the formula, x i is the elevation of each point within the grid, μ is the average elevation of all points within the grid, and n is the number of points within the grid.

[0035] Furthermore, in the aforementioned final pressing process, the calculation formula for each grid position is as follows:

[0036]

[0037]

[0038] In the formula, (N) x ',N y (x0', y0') represents the positioning coordinates of the grid center point N', (x1', y1') represent the position coordinates of the two vehicle-mounted positioning mobile stations on the road roller, l1 represents the length of the line connecting the left laser on the road roller to the two vehicle-mounted positioning mobile stations, b1 represents the distance from the laser on the road roller to the center point N' of a certain grid on the ground, δ1 represents the scattering angle, and α1 represents the angle between the multi-line laser corresponding to the grid center point and the horizontal.

[0039] Furthermore, after determining the flatness of each grid cell, the following steps are also included:

[0040] Based on the flatness value, the grid is divided into layers, and the grids at different levels are marked with different colors.

[0041] The beneficial effects achieved by this invention are as follows:

[0042] 1. By processing the road surface into a grid and calculating the average height of the road surface within each grid, automatic leveling is achieved, and reverse paving is performed to achieve a smooth final road surface after compaction.

[0043] 2. During the final compaction process, multi-line laser and positioning technology are used to more accurately measure the undulation and smoothness of the road surface and display relevant information in real time. This makes it easier for operators to handle the road roller, improves the efficiency and quality of road construction, reduces the difficulty and labor intensity of operators, and realizes intelligent and automated control. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the reverse paving method of the present invention;

[0045] Figure 2 This is a schematic diagram of the UI interface of the on-board display for the road roller of the present invention;

[0046] Figure 3 This is a schematic diagram of the installation position (left view) and distance measurement of the multi-line laser on the paver of the present invention;

[0047] Figure 4 This is a top view and a schematic diagram of the multi-line laser installation position and ranging of the paver of the present invention;

[0048] Figure 5 This is a schematic diagram (left view) of the multi-line laser installation position on the road roller of the present invention;

[0049] Figure 6 This is a top view showing the installation position of the multi-line laser on the road roller of the present invention.

[0050] Figure 7 This is a schematic diagram of road surface gridding. Detailed Implementation

[0051] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments and specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations thereof. In the absence of conflict, the embodiments and technical features in the embodiments can be combined with each other.

[0052] Example 1:

[0053] This embodiment discloses a road detection system based on process control, including a paver, a road roller, a multi-line laser, a positioning base station, a vehicle-mounted positioning mobile station, and a vehicle-mounted processor.

[0054] The paver is a type of road construction machinery and equipment that can spread road construction materials evenly and flat.

[0055] The road roller is a type of road construction machinery and equipment that can compact the road surface laid by the paver.

[0056] The multi-line laser can measure the distance from multiple target points on a plane to the laser mounting location.

[0057] The positioning base station uses real-time dynamic differential positioning technology, which can receive satellite positioning signals, provide a reference point for the vehicle-mounted positioning mobile station, and transmit the positioning signal to the vehicle-mounted positioning mobile station.

[0058] The vehicle-mounted positioning mobile station can receive signals from the positioning base station to determine the location of the vehicle on which the positioning device is installed.

[0059] The on-board processor is an electronic device with storage and processing functions. It can process data from various data acquisition devices of the road roller (multi-line laser, positioning base station, and on-board positioning mobile station), install programs, process data, and display the input data.

[0060] Example 2

[0061] This embodiment discloses a road inspection method based on process control, specifically including two parts: a variable automatic leveling method for paving and an online smoothness detection method using a final compaction roller. The implementation steps of the variable automatic leveling method for paving are as follows:

[0062] Step 1: Install a multi-line laser. The paver is equipped with a vehicle-mounted positioning mobile station, which can obtain the paver's location information and vehicle direction information. For example... Figure 3 , Figure 4 As shown, supports are erected on the left and right sides in front of the hopper, with one multi-line laser mounted on each support. Using the plane where the paver's tracks are located as the reference plane, the undulations of the unpaved area in front of the paver relative to the reference plane can be scanned. The two multi-line lasers transmit data via a bus, maintaining a consistent baud rate, with the other end of the bus connected to the onboard processor.

[0063] Step 2: Grid-based road surface. For example... Figure 7 As shown, the area scanned by multi-line laser is rasterized, that is, the road surface is divided into small areas of a certain size, each of which is called a grid. Based on the elevation information of the area scanned by multi-line laser, the average value is taken as the actual height data of the grid, thereby describing the overall and local undulation of the road surface.

[0064] Step 3: Determine the grid height and its position. (Combined with...) Figure 3The grid height h is calculated as h = h - laser - b sin(α), where h - laser is the height from the multi-line laser installation position to the plane where the paver track is located, b is the distance from the center point N of the ground grid measured by the multi-line laser to the multi-line laser, and α is the angle between the multi-line laser corresponding to the grid center point and the horizontal plane. The heights of each column of grids are compared, and the average value of that column of grids is used as the actual height data of the road surface in that column, thereby describing the undulation of the road surface in that column relative to the reference plane.

[0065] The current paver position is determined by positioning data provided by the positioning base station and the vehicle-mounted positioning mobile station. Based on the installation location of the multi-line laser and the distance information from the multi-line laser to the scanned road surface, the position information of the center point of each road grid can be determined. Specifically, the position information of the grid center point can be determined by the following method:

[0066] Based on the positioning information, let the coordinates of the two vehicle-mounted positioning mobile stations used for positioning and orientation on the paver be A(x0,y0) and B(x1,y1), respectively. Let the length of the line connecting the left laser L to AB be l, and the lateral distance to point A be a. Let the distance from the center point N of a certain grid on the ground to the laser be b, and the scattering angle be δ. Let the angle between the laser corresponding to the grid center point and the horizontal be α. The equation of the line containing AB can be obtained as follows:

[0067]

[0068] The coordinates C of the left laser beam perpendicular to point AB are:

[0069]

[0070] The coordinates of the center point of the grid are:

[0071]

[0072]

[0073] Step 4: Determine the paving thickness. Based on the positioning data and the paver's structure, the location of the screed can be determined. When the screed reaches the designated grid position, i.e., the aforementioned (N) x N y At point ), adjust the height of the screed to achieve a reverse paving state. The reverse paving state is characterized by, considering the loose paving coefficient during the paving process, paving materials of different thicknesses are laid according to different degrees of undulation of the original road surface; that is, more material is laid in areas with lower original road surfaces and less material is laid in areas with higher original road surfaces.

[0074] like Figure 1 As shown, let h0 be the height of the original road surface relative to the reference plane (i.e., the plane where the paver tracks are located), and let h be the preset compacted paving thickness.set The loose paving coefficient is k sp The required paving thickness h tp for:

[0075] h tp =h0+(h set -h0)·k sp

[0076] The steps for implementing the online flatness detection method using a final-compaction roller are as follows:

[0077] Step 1: Install a multi-line laser. (For example...) Figure 6 , Figure 7 As shown, final compaction is completed by a single-drum roller, which is equipped with a vehicle-mounted positioning mobile station to obtain the roller's location and vehicle direction information. Two multi-line lasers are used, one installed at the center of the front side of the roller's front frame and the other at the center of the rear side of the rear frame, to scan the road undulations in front of and behind the roller.

[0078] Step 2: Rasterizing the road surface. The area scanned by the multi-line laser is rasterized, that is, the road surface is divided into small areas of a certain size, each of which is called a grid.

[0079] Step 3: Determine the grid flatness and its location. Based on the elevation information of the area obtained by multi-line laser scanning, calculate the flatness information within each grid and between it and its longitudinally adjacent grids. The flatness information within the grid is calculated using the following formula:

[0080]

[0081] Where, x i is the elevation of each point within the grid, μ is the average elevation of all points within the grid, and n is the number of points within the grid.

[0082] The flatness of the longitudinally adjacent grids is determined by averaging the flatness of two adjacent grids.

[0083] The current location of the road roller is determined by positioning data provided by the positioning base station and the vehicle-mounted positioning mobile station. Based on the laser installation location and the distance from the laser to the scanned road surface, the location information of the center point of each road grid can be determined. The location information of the grid center point can be determined by the following method:

[0084] Based on the positioning information, let the positioning coordinates of the two vehicle-mounted mobile positioning stations used for positioning and orientation on the road roller be A'(x0',y0') and B'(x1',y1') respectively. Let l1 be the length of the line connecting laser L to the center point of A'B'. Let b1 be the distance from the center point N' of a certain grid on the ground to the laser, and let δ1 be the scattering angle. Let α1 be the angle between the laser and the horizontal plane corresponding to the grid center point. Then the positioning coordinates of the grid center point are:

[0085]

[0086]

[0087] Step Four: Data Display. Different areas with varying smoothness are marked with different colors. For example, grids with a smoothness greater than 1 are marked in red, grids with a smoothness between 0.8 and 1 are marked in orange, and grids with a smoothness less than 0.8 are marked in green. These markings are displayed in the cab to facilitate the operator's vibration testing of the road roller on uneven surfaces. After the road roller has passed over an uneven area, a multi-line laser mounted on the rear frame scans the road surface again using the same steps to provide feedback on the surface finishing effect.

[0088] Preferably, such as Figure 2 As shown, the display also shows a diagram of the current vehicle position, a diagram of road smoothness, the current lane markings, the distance to the next uneven surface, and information on the smoothness of the compacted road surface. The operator can use this information to operate the roller on the uneven road surface, thus enabling online detection of road smoothness.

[0089] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A road detection method based on process control, characterized in that, Based on a process control-based road detection system, the system includes a paver, a roller, a multi-line laser, an on-board processor, a positioning base station, and an on-board positioning mobile station; The paver is used to spread road construction materials evenly and smoothly. The road roller is used to compact the road surface laid by the paver; The multi-line laser is used to measure the distance from multiple target points on a plane to the laser mounting location; The positioning base station, based on real-time dynamic differential positioning technology, is used to receive satellite positioning signals, provide reference points for the vehicle-mounted positioning mobile station, and transmit positioning signals to the vehicle-mounted positioning mobile station. The vehicle-mounted positioning mobile station is used to receive signals from the positioning base station to determine the location of the vehicle on which the positioning device is installed. The vehicle-mounted processor is used to receive measurement data from multi-line laser and vehicle-mounted positioning mobile station, process the data, and output the predetermined paving thickness. The method includes the following steps: During the paving process, the construction area is scanned in real time, and the road surface within the scanned area is divided into several grids of the same size; Determine the height and position of each grid cell; The paving thickness is determined based on the grid height, and the screed is controlled to reach the grid position for reverse paving. The steps to determine the grid height include: The height of each grid cell within the scanned area Perform the calculation: In the formula The angle between the multi-line laser corresponding to the center point of the grid and the horizontal. The distance from the center point N of the grid measured by laser on the paver to the multi-line laser. The height from the installation position of the multi-line laser on the paver to the plane where the paver tracks are located; The step of determining the paving thickness based on grid height includes: Based on the height of each grid cell, the average height of the grid cells in the same column is calculated, and the calculated average height is recorded as the height of the road surface in that column relative to the plane where the paver track is located. , Calculate the paving thickness: ， In the formula, For paving thickness, This is to preset the actual thickness after compaction. The loose paving coefficient; After the reverse phase paving is completed, the following steps are also included: During the final compaction process, the construction area is re-scanned, and the road surface within the scanned area is divided into several grids of the same size; Determine the flatness and location of each grid cell; Control the road roller to reach the grid position and start vibration based on the flatness.

2. The road detection method based on process control according to claim 1, characterized in that, The formula for calculating the position of each grid cell is: ， In the formula, The coordinates of the grid center point N are: These are the location coordinates of two vehicle-mounted mobile positioning stations on the paver. This refers to the length of the line connecting the left laser on the paver to the two vehicle-mounted positioning mobile stations. For the left laser on the paver lateral distance, To measure the distance from the center point N of a certain grid on the ground to the multi-line laser on the paver, For the scattering angle, The angle between the multi-line laser and the horizontal direction corresponding to the grid center point N.

3. The road detection method based on process control according to claim 1, characterized in that, The flatness of each grid The calculation formula is: ， In the formula, x i is the elevation of each point within the grid, μ is the average elevation of all points within the grid, and n is the number of points within the grid.

4. The road detection method based on process control according to claim 1, characterized in that, During the final pressing process, the calculation formula for each grid position is: ， ， In the formula, The coordinates of the grid center point N' are given. The coordinates of two vehicle-mounted mobile positioning stations are displayed on the road roller. This refers to the length of the line connecting the left laser on the road roller to the two vehicle-mounted positioning mobile stations. To measure the distance from the center point N' of a certain grid on the ground to the laser on the road roller. For the scattering angle, The angle between the multi-line laser corresponding to the center point of the grid and the horizontal.

5. The road detection method based on process control according to claim 1, characterized in that, After determining the flatness of each grid cell, the following steps are also included: Based on the flatness value, the grid is divided into layers, and the grids at different levels are marked with different colors.

Images