Building detection unmanned aerial vehicle hollow area calculation method and system

Abstract

The application discloses a building detection unmanned aerial vehicle hollow area calculation method and system, and belongs to the technical field of unmanned aerial vehicle application; the method adopts a method of equally spacing knocking from up to down at standard operation rectangular surface to complete the whole standard operation rectangular surface knocking detection (the number of knocking points is unlimited), three hollow points close to each other are used to determine a triangular area, then the hollow areas in the standard operation rectangular surface are accumulated and positioned, and the whole wall hollow area can be calculated by combining and counting the small hollow areas in N standard operation rectangular surfaces.

Description

Technical Field

[0001] This invention relates to the field of unmanned aerial vehicle (UAV) application technology, and in particular to a method for calculating the area of ​​voids in a building inspection UAV. Background Technology

[0002] Currently, there is a need for quality inspection and maintenance during the construction and use of buildings, thus requiring quality inspection and maintenance work. Traditional inspection and maintenance methods involve personnel working at heights, carrying equipment to inspect and maintain buildings. For detecting hollow areas in walls, the method generally involves manually tapping and listening to the sound, using a hammer to tap the exterior wall surface and relying on the inspector's experience to make a judgment. This method is limited by the inspection conditions and cannot inspect a large area at once, resulting in high labor intensity and low efficiency. Summary of the Invention

[0003] The purpose of this invention is to address the above-mentioned problems by providing a method for calculating the area of ​​voids on building surfaces using a building inspection drone, which employs grid-based tapping detection to calculate the area of ​​voids on building surfaces.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A method for calculating the void area of ​​a building inspection drone includes the following:

[0006] Step S1: Construct the drone flight operation coordinate plane: Construct an operation coordinate plane parallel to the building surface at a certain safe distance outside the building surface to be inspected for air bubbles, so that the drone will hover and fly over the operation coordinate plane.

[0007] Step S2: Set the knocking detection operation standard, including: Step S21: Define the square coverage area that the UAV can perform knocking detection on the building surface at each hovering flight point as the standard operation rectangle, set the length and width of the standard operation rectangle and the spacing between knocking points, and arrange each knocking point along the horizontal and vertical directions of the standard operation rectangle according to the knocking point spacing; Step S22: Use a pre-built coordinate transformation model to determine the extension length and angle of the robotic arm under each knocking point, and update the corresponding transformed coordinate relationship between the coordinate parameters of each knocking point and the spatial coordinate parameters of the UAV flight.

[0008] Step S3: Plan the hovering points and flight paths of the UAV on the working coordinate plane. Use the length of the standard working rectangle as the horizontal spacing between hovering points and the width of the standard working rectangle as the vertical spacing. Perform hovering flight tasks at each hovering point one by one according to the preset flight path. At each hovering point, perform a tapping detection operation to obtain the coordinate data and hollow points of each tapping point. Then, calculate the area of ​​the hollow points enclosed by the hollow points. The specific processing flow of the tapping detection operation is as follows:

[0009] Determine the current tapping point: Based on the initial tapping point of the standard operation rectangle and the current hovering point, skip the previous tapping points that have already been tapped at the previous hovering point on the outer perimeter of the standard operation rectangle, and determine the current tapping point where the tapping operation will be performed at the current hovering point.

[0010] Obtain the coordinates of the current tapping point: Based on the coordinates of the current hovering point, use the coordinate transformation model to obtain the coordinates of each current tapping point;

[0011] Tapping point detection and judgment: At the current hovering point, tapping trajectory is followed horizontally row by row or vertically column by column. Tapping detection is performed on the current tapping point of the standard working rectangle one by one. Tapping data of each current tapping point is obtained in sequence, and it is determined whether the current tapping point is a hollow point.

[0012] Calculate the hollow area of ​​the standard operation rectangular surface: Based on the coordinate data of the hollow points at the current hovering point, as the tapping operation is performed, the area of ​​the triangle enclosed by the three adjacent hollow points is calculated step by step, and then the areas are accumulated to obtain the hollow area of ​​the standard operation rectangular surface at the current hovering point.

[0013] Step S4: Calculate and merge the hollow areas of the standard working rectangular surfaces at each hovering point to obtain the hollow area of ​​the building surface to be inspected.

[0014] The processing procedure of the coordinate transformation model in step S2 is as follows: Based on the set length and width of the standard working rectangle and the safe distance of the working coordinate plane, the extension length and angle of the UAV robotic arm under the condition that the four vertices of the standard working rectangle are used as striking points are determined; then, based on the set spacing between striking points, the extension length and angle of the robotic arm under each striking point are determined; then, based on the extension length and angle of the robotic arm under each striking point and the safe distance of the working coordinate plane, the corresponding transformed coordinate relationship between the coordinate parameters of each striking point and the spatial coordinate parameters of the UAV flight is obtained.

[0015] Based on the aforementioned scheme, in an improved scheme, the processing of the coordinate transformation model in step S2 further includes the following: using one of the four vertices of the standard work rectangle as a reference point, the extension length and angle of the robotic arm under each striking point condition are checked, and the checked transformed coordinate relationship of each striking point is updated. This achieves the purpose of checking and improving accuracy.

[0016] The aforementioned solution, which improves work efficiency by performing large-interval single tapping, is improved in an enhanced solution. To further improve the accuracy of hollow detection, step S3 includes a re-inspection mode. In this mode, the process for calculating the hollow area of ​​the standard rectangular surface is as follows: It is determined whether a hollow boundary exists within the right-angled triangle formed by three of the four current tapping points (two adjacent rows and two columns). If a hollow boundary exists, tapping is performed at re-inspection intervals in the area between the hollow and solid points of the current right-angled triangle. Then, based on the coordinates of the hollow points at the current hovering point, the area of ​​the triangle formed by the three adjacent hollow points is calculated progressively as the tapping operation continues. Otherwise, the area of ​​the current right-angled triangle is calculated progressively, and then these calculations are accumulated to obtain the hollow area of ​​the standard rectangular surface at the current hovering point. This allows for small-interval secondary tapping re-inspection of the area between the hollow and solid points, effectively improving the overall accuracy of hollow detection. In step S3, the tapping detection operation, under the re-inspection processing mode, involves the following specific processing flow for calculating the hollow area of ​​the standard rectangular surface:

[0017] Determine the boundary of hollow areas: Mark each current tapping point as either a hollow point or a solid point. In real time, determine whether there is a hollow boundary in the right triangle formed by three of the four current tapping points covered by two adjacent rows and two columns. If both hollow and solid points exist in the three current tapping points of the right triangle, it is determined that there is a hollow boundary in the current right triangle and the hollow area of ​​the hollow boundary is calculated. Otherwise, there is no hollow boundary and the hollow area of ​​the non-hollow boundary is calculated.

[0018] Calculate the area of ​​the hollow area at the boundary of the hollow area: Arrange preliminary inspection points along the horizontal and vertical directions at re-inspection intervals on the edge and inner perimeter of the current right-angled triangle face. Then, determine the preliminary inspection points on the line connecting the vertices of the hollow points and the solid points of the right-angled triangle face as the tapping re-inspection points. Perform tapping detection on each preliminary inspection point or tapping re-inspection point of the current right-angled triangle face, sequentially acquiring the tapping data of each preliminary inspection point or tapping re-inspection point, and determine whether the preliminary inspection point or tapping re-inspection point is a hollow point based on this data. Based on the current hovering point coordinate data, use a coordinate transformation model to obtain the coordinate data of each preliminary inspection point or tapping re-inspection point. Based on the re-inspection point coordinate data, as the tapping operation is performed, progressively calculate the area of ​​the triangle enclosed by the three adjacent hollow points of the current right-angled triangle face, and then sum them to obtain the area of ​​the hollow area of ​​the current right-angled triangle face. The tapping point spacing is an integer multiple of the re-inspection interval.

[0019] Calculate the area of ​​the hollow area at the non-hollow boundary: Based on the coordinate data of the three hollow points of the right-angled triangle face, the area of ​​the current right-angled triangle face is calculated step by step as the tapping operation is performed;

[0020] Accumulated calculation of void area: The void areas at the void boundary and the void areas at the non-void boundary are accumulated to obtain the void area of ​​the standard working rectangular surface at the current hovering point.

[0021] By adopting the above technical solution, the present invention has the following beneficial effects:

[0022] 1. This invention uses a method of tapping at equal distances between the upper and lower tapping points within a standard rectangular surface to complete the tapping detection of the entire standard rectangular surface (the number of tapping points is unlimited). The triangular area is determined by the three adjacent hollow points, and then the hollow areas within the standard rectangular surface are accumulated. The total hollow area of ​​the wall can be calculated by merging the small hollow areas within N standard rectangular surfaces to obtain the large hollow area identification calculation for the entire wall surface. Attached Figure Description

[0023] Figure 1 This is a flowchart of the calculation method of the present invention.

[0024] Figure 2 This is a layout diagram of the striking path for the standard rectangular surface of this invention.

[0025] Figure 3 This is a layout diagram of the hovering tapping route for the building surface to be tested for hollowness according to the present invention.

[0026] Figure 4 This is a system block diagram of the computing system of the present invention. Detailed Implementation

[0027] The specific implementation of the invention will be further described below with reference to the accompanying drawings.

[0028] It should be noted that the drone and the knocking detection technology used in this invention are existing technologies, and reference can be made to the applicant's prior applications for drone knocking detection technology for identifying voids. Based on the design of the drone and the knocking detection technology for identifying voids, it can be designed to allow only a single knocking point at each hovering point; it can also be designed with a vertical angle adjustment mechanism to allow only multiple horizontal knocking points in a single row at each hovering point; it can also be designed with a horizontal angle adjustment mechanism to allow only multiple vertical knocking points in a single column at each hovering point; and it can also be designed with both horizontal and vertical angle adjustment mechanisms to allow multiple rows and columns of knocking points (rectangular surface coverage) at each hovering point. To reduce drone hovering points and minimize positioning interference, this invention preferably uses a standard rectangular surface with multiple rows and columns of knocking points as an example for explanation.

[0029] Example 1

[0030] like Figures 1-3 As shown in Embodiment 1, a method for calculating the void area of ​​a building inspection drone includes the following:

[0031] Step S1: Construct the drone flight operation coordinate plane: Construct an operation coordinate plane parallel to the building surface at a certain safe distance outside the building surface to be inspected, so that the drone will hover and fly over the operation coordinate plane.

[0032] The on-site survey determined the safe distance setting for this drone to detect hollow areas on the wall. For example, if the safe distance is 0.5 meters, the parallel plane of the wall surface at 0.5 meters from the wall is defined as the working coordinate plane, which is the drone's spatial safe coordinate plane.

[0033] Step S2: Set the knocking detection operation standard, including: Step S21: Define the square coverage area that the UAV can perform knocking detection on the building surface at each hovering flight point as the standard operation rectangle. Set the length and width of the standard operation rectangle and the spacing between knocking points. Arrange each knocking point (one knocking point) on the standard operation rectangle along the horizontal and vertical directions according to the knocking point spacing. Step S22: Use a pre-built coordinate transformation model to determine the extension length and angle of the robotic arm under each knocking point condition, and update the corresponding transformation coordinate relationship between the coordinate parameters of each knocking point and the spatial coordinate parameters of the UAV flight.

[0034] The processing steps of the coordinate transformation model in step S2 are as follows: Based on the set length and width of the standard working rectangle and the safe distance of the working coordinate plane, the extension length and angle of the UAV robotic arm are determined when the four vertices of the standard working rectangle are used as striking points; then, based on the set spacing between striking points, the extension length and angle of the robotic arm are determined for each striking point; finally, based on the extension length and angle of the robotic arm for each striking point and the safe distance of the working coordinate plane, the corresponding transformed coordinate relationships between the coordinate parameters of each striking point and the spatial coordinate parameters of the UAV flight are obtained. Finally, by combining the real-time spatial coordinate data of the UAV hovering flight points, the coordinate data of each striking point can be obtained.

[0035] The standard operating rectangle (defined as the standard operating rectangle) is defined as the rectangular (or square) surface that the drone's robotic arm can tap at a distance of 0.5 meters, through left-right and up-down adjustments. The length and width of the standard operating rectangle are determined (corresponding to the extension angle and length on the robotic arm; this length and width have maximum values, so the area can be selected based on the maximum value). The four right-angle points (single tapping points) of the standard operating rectangle are A, B, C, and D. Under the current attitude of the drone, the extension angle and length on the robotic arm corresponding to these four right-angle points and each tapping point within them will be determined.

[0036] Step S3: Plan the hovering points and flight paths of the UAV on the operational coordinate plane. Use the length of the standard operational rectangle as the horizontal spacing between hovering points and the width of the standard operational rectangle as the vertical spacing. Perform hovering flight tasks at each hovering point one by one according to the preset flight path. At each hovering point, perform a tapping detection operation to obtain the coordinate data and hollow points of each tapping point. Then, calculate the area of ​​the hollow points enclosed by these hollow points. The specific processing flow of the tapping detection operation is as follows:

[0037] Determine the current tapping point: Based on the initial tapping point m of the standard operation rectangle and the current hovering point, skip the previous tapping point m1 (previous tapping point) where tapping has already been performed on the outer perimeter of the standard operation rectangle at the previous hovering point, and determine the current tapping point m2 where tapping will be performed at the current hovering point (m, m1, and m2 are auxiliary explanations to distinguish the tapping point at different times).

[0038] Obtain the coordinate data of the current tapping point: Based on the coordinate data of the current hovering point, use the coordinate transformation model to obtain the m2 coordinate data of each current tapping point;

[0039] Tapping point detection and judgment: At the current hovering point, tapping trajectory is followed horizontally row by row or vertically column by column. Tapping detection is performed on the current tapping point m2 of the standard working rectangle one by one. Tapping data of each current tapping point m2 is obtained in sequence, and it is determined whether the current tapping point m2 is a hollow point.

[0040] Calculate the area of ​​the hollow area of ​​the standard operation rectangular surface: Based on the coordinate data of the hollow point at the current hovering point, as the tapping operation is performed, the area of ​​the triangle enclosed by the three adjacent hollow points is calculated step by step, and then the areas are accumulated to obtain the area of ​​the hollow area of ​​the standard operation rectangular surface at the current hovering point.

[0041] With the assistance of a back-end computer or ground control station, the drone's flight path is planned and optimized. Hovering points are set at certain horizontal and vertical intervals, allowing the drone to complete the task of hovering and covering all the aerial parallel plane coordinates of the corresponding wall. At the same time, in-progress avoidance of inaccessible areas and areas where the robotic arm cannot reach improve the overall safety of the drone. During each hovering point, the robotic arm will extend to tap hollow spots according to the above-set standards to detect hollow spots and calculate the area of ​​hollow spots. If the coordinates are displaced due to wind or other reasons, they can be reset before continuing to complete the tapping at the designated point.

[0042] The standard operating procedure and calculation process for the hollow detection of the extended robotic arm are as follows: The robotic arm of the drone extends and taps to detect hollow areas. It uses the method of tapping at equal distances between the upper and lower tapping points within the standard working rectangular surface to complete the grid-like tapping detection of the entire standard working rectangular surface (the number of tapping points is unlimited); then the standard triangle area is determined by the three adjacent hollow points, and then the hollow points and hollow areas within the standard working rectangular surface are accumulated.

[0043] Step S4: Calculate and merge the hollow areas of the standard working rectangular surfaces at each hovering point to obtain the hollow area of ​​the building surface to be inspected. The hollow area of ​​the entire wall surface is calculated and merged by the back-end computer or drone from the local hollow areas within N standard working rectangular surfaces to complete the global hollow area identification and calibration calculation for the entire wall surface.

[0044] like Figure 2 As shown, a sample layout diagram of the tapping points and tapping routes for each single tapping operation on a standard rectangular surface is given. The tapping points are represented by large circles, arranged in four rows and four columns. The row and column spacing represents the tapping point spacing. Tapping is performed from top to bottom and left to right. The initial tapping point m in row j and column i is denoted by Qij. First, tapping Q11-Q14 is completed by moving downwards, then Q24-Q21 is completed by moving upwards back, then Q31-Q34 is completed by moving downwards again, and finally Q44-Q41 is completed by moving upwards back. For example... Figure 3As shown, a sample layout diagram of the hovering tapping route for a building surface to be inspected for hollow areas is given. Let the actual hollow area be K0. Large circles represent tapping points, small circles with a center line represent hovering points (center of the standard operating rectangle), and diagonal dashed lines represent the size of the standard operating rectangle. The building surface to be inspected includes four standard operating rectangles. The drone hovering route is P1-P2-P3-P4. After tapping inspection in standard mode, the standard hollow area is identified as K1. Furthermore, as... Figure 3 The diagram shows the calculation of the area of ​​the right triangle formed by three of the four current tapping points (m2) covering two adjacent rows and two columns. Alternatively, in other cases (where adjacent tapping points extend beyond the two-row, two-column coverage area, such as two rows and three columns, or two columns and three rows), the area of ​​the triangle formed by three adjacent current tapping points is calculated and then accumulated to obtain the area of ​​the hollow area of ​​the standard operating rectangular surface. Specifically, at P1, tapping is completed according to the standard operating rectangular surface. Since the length of the standard operating rectangular surface is the horizontal spacing between the hovering points, the tapping points on the left side of P2 overlap. The rectangular dashed frame in the diagram represents the overlapping area. Therefore, it is necessary to first determine the tapping points to be tapped. At P2, skip columns Q11-Q14, directly proceed upwards to complete tapping Q24-Q21, then downwards to complete tapping Q31-Q34, and then upwards again to complete tapping Q44-Q21. Q41; Similarly, at P3, skip the single row Q11-Q41, proceed downwards to complete the tapping of Q12-Q14, upwards to complete the tapping of Q24-Q22, then downwards to complete the tapping of Q32-Q34, then upwards back to complete the tapping of Q44-Q42; Similarly, at P4, skip the single row Q11-Q41 and the single column Q41-Q44, proceed downwards to complete the tapping of Q12-Q14, upwards to complete the tapping of Q24-Q22, then downwards to complete the tapping of Q32-Q34. When the building surface is vertical, the distance between hollow points can be directly calculated by adding or subtracting coordinate data in the same direction; when the building surface is inclined, the distance between hollow points can be calculated by combining coordinate data with the inclination angle of the building surface; then, the area of ​​the triangle enclosed by the hollow points can be calculated based on the distance between the hollow points.

[0045] Example 2

[0046] Based on the aforementioned Embodiment 1, in this Embodiment 2, the processing procedure of the coordinate transformation model in step S2 is further as follows: taking one of the four vertices of the standard work rectangular surface as a reference point, the extension length and angle of the robotic arm under each striking point condition are checked, and the checked transformed coordinate relationship of each striking point is updated.

[0047] For example, a building inspection drone flies at a safe distance of 0.5 meters parallel to the wall, using a point on the wall as the work reference point (point A). The extension length and angle of the robotic arm at point A are restored, and the extension length and angle of the robotic arm under various tapping points are calibrated. Then, the drone can obtain the spatial coordinate point parameters of the drone on the work surface corresponding to the 0.5-meter distance from the wall.

[0048] In this way, it plays a role in calibrating and improving accuracy under the current attitude of the drone.

[0049] Example 3

[0050] As mentioned above, in order to improve work efficiency, the first hollow detection in Embodiment 1 or Embodiment 2 can adopt a large spacing of tapping points (e.g., 15cm). At this time, the error in judging the hollow boundary (the spacing of the tapping points) is relatively large. In order to further improve the accuracy of hollow detection, this Embodiment 3 sets a secondary re-inspection mode. The secondary re-inspection can be carried out under the guidance of ground control station or background calculation and UAV control center, targeting the area between the hollow point and the solid point with small-spacing tapping re-inspection (e.g., 5cm, or even 3cm), reducing the error in judging the hollow boundary and improving the overall accuracy of hollow detection. The details are as follows:

[0051] To further improve the accuracy of hollow detection, in this embodiment 3, in addition to the standard processing mode of the tapping detection operation in embodiment 1, the tapping detection operation in step S3 also includes a re-inspection processing mode. In this case, the processing flow for calculating the hollow area of ​​the standard operation rectangular surface in step S3 is as follows: Determine whether there is a hollow boundary in the right-angled triangle (isosceles right-angled triangle) formed by three of the four current tapping points m2 covered by two adjacent rows and two columns. If a hollow boundary exists, tapping detection is performed in the area between the hollow points and solid points of the current right-angled triangle surface according to the re-inspection interval. Then, based on the coordinate data of the hollow points at the current hovering point, as the tapping operation is executed, the area of ​​the triangle formed by the three adjacent hollow points of the current right-angled triangle surface is gradually calculated; otherwise, the area of ​​the current right-angled triangle surface is gradually calculated, and then accumulated to obtain the hollow area of ​​the standard operation rectangular surface at the current hovering point. In the re-inspection processing mode of the tapping detection operation in step S3, the specific processing flow for calculating the hollow area of ​​the standard operation rectangular surface is preferably as follows:

[0052] Determine the hollow boundary: Mark each current tapping point m2 as a hollow point (a hollow point from a single tap) or a solid point. In real time, determine whether there is a hollow boundary in the right triangle formed by 3 of the 4 current tapping points m2 covered by two adjacent rows and two columns. When the 3 current tapping points m2 of the right triangle have both hollow points and solid points, it is determined that there is a hollow boundary in the current right triangle and the hollow area of ​​the hollow boundary is calculated. Otherwise, there is no hollow boundary and the hollow area of ​​the non-hollow boundary is calculated.

[0053] Calculate the area of ​​the hollow area at the boundary of the hollow area: Arrange preliminary inspection points along the horizontal and vertical directions on the edge and inner perimeter of the current right-angled triangle face at inspection intervals (in other examples). Then, determine the preliminary inspection points on the line connecting the hollow point vertex and the solid point vertex of the right-angled triangle face as the tapping inspection points (secondary tapping points). Perform tapping detection on each tapping inspection point of the current right-angled triangle face, sequentially acquiring the tapping data for each tapping inspection point, and determine whether the tapping inspection point is a hollow point (secondary tapping hollow point) based on this data. Based on the current hovering point coordinate data, use a coordinate transformation model to obtain the coordinate data of each tapping inspection point. Based on the inspection point coordinate data, as the tapping operation is performed, progressively calculate the area of ​​the triangle formed by the three adjacent hollow points (first-time tapping hollow point and second-time tapping hollow point) of the current right-angled triangle face, and then sum them to obtain the area of ​​the hollow area of ​​the current right-angled triangle face; where the tapping point spacing is an integer multiple of the inspection interval.

[0054] Calculate the area of ​​the hollow area at the non-hollow boundary: Based on the coordinate data of the three hollow points of the right-angled triangle face, the area of ​​the current right-angled triangle face is calculated step by step as the tapping operation is performed;

[0055] Accumulated calculation of void area: The void areas at the void boundary and the void areas at the non-void boundary are accumulated to obtain the void area of ​​the standard working rectangular surface at the current hovering point.

[0056] like Figure 3 As shown, an example layout diagram of the hovering tapping route for a building surface to be inspected for hollowness is given. Small circles represent re-inspection points. When it is determined that the three current tapping points m2 on the right-angled triangular surface simultaneously contain both hollow and solid points, preliminary re-inspection points with a spacing of 5cm are added to the square surface with a tapping point spacing of 15cm. This determines the tapping re-inspection points. Then, tapping is performed along the horizontal, vertical, and diagonal sides from the hollow point to the solid point until all re-inspection points are tapped, or until the re-inspection point on the route is determined to be a solid point. Only then is the next tapping point m2 tapped. The actual hollow area is K0. The standard detection hollow area obtained through tapping in the standard mode is K1, and the re-inspection detection hollow area obtained through tapping in the re-inspection mode is K2.

[0057] As described above, the preliminary re-inspection points and tapping points of this invention are arranged in an equidistant square grid, although other grid shapes can also be used. Of course, compared to the aforementioned example of tapping the re-inspection points, in another example with better detection accuracy but lower efficiency, the preliminary re-inspection points are directly tapped. In this case, the process of calculating the hollow area of ​​the hollow boundary is as follows: Preliminary re-inspection points are arranged along the horizontal and vertical directions at re-inspection intervals on the edge and inner periphery of the current right-angled triangle face; tapping detection is performed on the preliminary re-inspection points of the current right-angled triangle face one by one, obtaining the tapping data of each preliminary re-inspection point sequentially, and determining whether the preliminary re-inspection point is a hollow point; based on the current hovering point coordinate data, the coordinate data of each preliminary re-inspection point is obtained using a coordinate transformation model; based on the re-inspection point coordinate data, as the tapping operation is performed, the area of ​​the triangle enclosed by the three adjacent hollow points of the current right-angled triangle face is gradually calculated, and then accumulated to obtain the hollow area of ​​the current right-angled triangle face.

[0058] In this way, a small-interval secondary tapping test can be performed on the area between the hollow and solid points after a single tapping, effectively improving the overall accuracy of hollow detection.

[0059] Example 4

[0060] Based on the calculation methods of the aforementioned Embodiment 1, Embodiment 2, or Embodiment 3, the hollow area calculation system of this Embodiment 4 is constructed. Please refer to the aforementioned Embodiments 1-3 for examples of combinations of technical features and their specific solutions.

[0061] like Figure 4 As shown in Embodiment 4, a system for calculating the void area of ​​a building inspection drone includes the following:

[0062] Module: Used to construct the drone flight operation coordinate plane: Construct an operation coordinate plane parallel to the building surface at a certain safe distance outside the building surface to be inspected for air bubbles, so that the drone will hover and fly over the operation coordinate plane;

[0063] Setting module: Used to set the standards for the tapping detection operation, including: Step S21, defining the square coverage area that the UAV can perform tapping detection on the building surface at each hovering flight point as the standard operation rectangle, setting the length and width of the standard operation rectangle and the spacing between tapping points, and arranging each tapping point along the horizontal and vertical directions of the standard operation rectangle according to the spacing between tapping points; Step S22, using a pre-built coordinate transformation model, determining the extension length and angle of the robotic arm under each tapping point condition, and updating the corresponding transformation coordinate relationship between the coordinate parameters of each tapping point and the spatial coordinate parameters of the UAV flight.

[0064] The detection and calculation module is used to plan the hovering points and flight paths of the UAV on the operational coordinate plane. The horizontal spacing between hovering points is based on the length of the standard operational rectangle, and the vertical spacing is based on the width of the standard operational rectangle. Hovering flight tasks are performed on each hovering point one by one according to the preset flight path. At each hovering point, a tapping detection operation is performed to obtain the coordinate data and hollow points of each tapping point. The area of ​​the hollow points is then calculated by summing these data. The specific processing flow of the tapping detection operation is as follows:

[0065] Determine the current tapping point: Based on the initial tapping point m of the standard operation rectangle and the current hovering point, skip the previous tapping point m1 that has already performed tapping operations on the outer periphery of the standard operation rectangle at the previous hovering point, and determine the current tapping point m2 where the tapping operation will be performed at the current hovering point.

[0066] Obtain the coordinate data of the current tapping point: Based on the coordinate data of the current hovering point, use the coordinate transformation model to obtain the m2 coordinate data of each current tapping point;

[0067] Tapping point detection and judgment: At the current hovering point, tapping trajectory is followed horizontally row by row or vertically column by column. Tapping detection is performed on the current tapping point m2 of the standard working rectangle one by one. Tapping data of each current tapping point m2 is obtained in sequence, and it is determined whether the current tapping point m2 is a hollow point.

[0068] Calculate the hollow area of ​​the standard operation rectangular surface: Based on the coordinate data of the hollow points at the current hovering point, as the tapping operation is performed, the area of ​​the triangle enclosed by the three adjacent hollow points is calculated step by step, and then the areas are accumulated to obtain the hollow area of ​​the standard operation rectangular surface at the current hovering point.

[0069] Statistics module: Used to calculate and merge the hollow areas of the standard rectangular surfaces at each hovering point to obtain the hollow area of ​​the building surface to be inspected.

[0070] The processing procedure of the coordinate transformation model in the setting module is as follows: Based on the set length and width of the standard working rectangle and the safe distance of the working coordinate plane, the extension length and angle of the UAV robotic arm under the condition that the four vertices of the standard working rectangle are used as striking points are determined; then, based on the set spacing between striking points, the extension length and angle of the robotic arm under each striking point are determined; finally, based on the extension length and angle of the robotic arm under each striking point and the safe distance of the working coordinate plane, the corresponding transformed coordinate relationship between the coordinate parameters of each striking point and the spatial coordinate parameters of the UAV flight is obtained.

[0071] It should be noted that the examples of the above embodiments can preferably be combined with one or more of each other according to actual needs, and the accompanying drawings of multiple examples adopt a set of combined technical features, which will not be described in detail here.

[0072] It should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation.

[0073] The above description is a detailed explanation and illustration of the preferred embodiments of the present invention. However, these descriptions are not intended to limit the scope of protection claimed by the present invention. All equivalent changes or modifications made under the technical teachings of the present invention should fall within the patent protection scope covered by the present invention.

Claims

1. A method for calculating the void area of ​​a building inspection drone, characterized in that, Includes the following: Step S1: Construct the drone flight operation coordinate plane: Construct an operation coordinate plane parallel to the building surface at a certain safe distance outside the building surface to be inspected for air bubbles, so that the drone will hover and fly over the operation coordinate plane. Step S2: Set the knocking detection operation standard, including: Step S21: Define the square coverage area that the UAV can perform knocking detection on the building surface at each hovering flight point as the standard operation rectangle, set the length and width of the standard operation rectangle and the spacing between knocking points, and arrange each knocking point along the horizontal and vertical directions of the standard operation rectangle according to the knocking point spacing; Step S22: Use a pre-built coordinate transformation model to determine the extension length and angle of the robotic arm under each knocking point, and update the corresponding transformed coordinate relationship between the coordinate parameters of each knocking point and the spatial coordinate parameters of the UAV flight. Step S3: Plan the hovering points and flight paths of the UAV on the working coordinate plane. Use the length of the standard working rectangle as the horizontal spacing between hovering points and the width of the standard working rectangle as the vertical spacing. Perform hovering flight tasks at each hovering point one by one according to the preset flight path. At each hovering point, perform a tapping detection operation to obtain the coordinate data and hollow points of each tapping point. Then, calculate the area of ​​the hollow points enclosed by the hollow points. The specific processing flow of the tapping detection operation is as follows: Determine the current tapping point: Based on the initial tapping point of the standard operation rectangle and the current hovering point, skip the previous tapping points that have already been tapped at the previous hovering point on the outer perimeter of the standard operation rectangle, and determine the current tapping point where the tapping operation will be performed at the current hovering point. Obtain the coordinates of the current tapping point: Based on the coordinates of the current hovering point, use the coordinate transformation model to obtain the coordinates of each current tapping point; Tapping point detection and judgment: At the current hovering point, tapping trajectory is followed horizontally row by row or vertically column by column. Tapping detection is performed on the current tapping point of the standard working rectangle one by one. Tapping data of each current tapping point is obtained in sequence, and it is determined whether the current tapping point is a hollow point. Calculate the hollow area of ​​the standard operation rectangular surface: Based on the coordinate data of the hollow points at the current hovering point, as the tapping operation is performed, the area of ​​the triangle enclosed by the three adjacent hollow points is calculated step by step, and then the areas are accumulated to obtain the hollow area of ​​the standard operation rectangular surface at the current hovering point. Step S4: Calculate and merge the hollow areas of the standard working rectangular surfaces at each hovering point to obtain the hollow area of ​​the building surface to be inspected.

2. The method for calculating the void area of ​​a building inspection drone according to claim 1, characterized in that: The processing procedure of the coordinate transformation model in step S2 is as follows: Based on the set length and width of the standard working rectangle and the safe distance of the working coordinate plane, the extension length and angle of the UAV robotic arm under the condition that the four vertices of the standard working rectangle are used as striking points are determined; then, based on the set spacing between striking points, the extension length and angle of the robotic arm under each striking point are determined; then, based on the extension length and angle of the robotic arm under each striking point and the safe distance of the working coordinate plane, the corresponding transformed coordinate relationship between the coordinate parameters of each striking point and the spatial coordinate parameters of the UAV flight is obtained.

3. The method for calculating the void area of ​​a building inspection drone according to claim 2, characterized in that: The processing steps of the coordinate transformation model in step S2 also include the following: taking one of the four vertices of the standard operation rectangular surface as a reference point, the extension length and angle of the robotic arm under each striking point are checked, and the checked transformed coordinate relationship of each striking point is updated.

4. The method for calculating the void area of ​​a building inspection drone according to claim 1, characterized in that: Step S3 of the tapping detection operation also includes a re-inspection processing mode. In this mode, the processing flow for calculating the hollow area of ​​the standard operation rectangular surface is as follows: determine whether there is a hollow boundary in the right-angled triangle formed by three of the four current tapping points covered by two adjacent rows and two columns; if there is a hollow boundary, tapping detection is performed in the area between the hollow points and solid points of the current right-angled triangle surface according to the re-inspection interval. Then, based on the coordinate data of the hollow points of the current hovering point, as the tapping operation is performed, the area of ​​the triangle formed by the three adjacent hollow points of the current right-angled triangle surface is calculated step by step; otherwise, the area of ​​the current right-angled triangle surface is calculated step by step, and then the results are accumulated to obtain the hollow area of ​​the standard operation rectangular surface at the current hovering point.

5. The method for calculating the void area of ​​a building inspection drone according to claim 4, characterized in that: In step S3, the tapping test operation, under the re-inspection processing mode, involves calculating the hollow area of ​​the standard rectangular surface. The specific processing flow is as follows: Determine the boundary of hollow areas: Mark each current tapping point as either a hollow point or a solid point. In real time, determine whether there is a hollow boundary in the right triangle formed by three of the four current tapping points covered by two adjacent rows and two columns. If both hollow and solid points exist in the three current tapping points of the right triangle, it is determined that there is a hollow boundary in the current right triangle and the hollow area of ​​the hollow boundary is calculated. Otherwise, there is no hollow boundary and the hollow area of ​​the non-hollow boundary is calculated. Calculate the area of ​​the hollow area at the boundary of the hollow area: Arrange preliminary inspection points along the horizontal and vertical directions at re-inspection intervals on the edge and inner perimeter of the current right-angled triangle face. Then, determine the preliminary inspection points on the line connecting the vertices of the hollow points and the solid points of the right-angled triangle face as the tapping re-inspection points. Perform tapping detection on each preliminary inspection point or tapping re-inspection point of the current right-angled triangle face, sequentially acquiring the tapping data of each preliminary inspection point or tapping re-inspection point, and determine whether the preliminary inspection point or tapping re-inspection point is a hollow point based on this data. Based on the current hovering point coordinate data, use a coordinate transformation model to obtain the coordinate data of each preliminary inspection point or tapping re-inspection point. Based on the re-inspection point coordinate data, as the tapping operation is performed, progressively calculate the area of ​​the triangle enclosed by the three adjacent hollow points of the current right-angled triangle face, and then sum them to obtain the area of ​​the hollow area of ​​the current right-angled triangle face. The tapping point spacing is an integer multiple of the re-inspection interval. Calculate the area of ​​the hollow area at the non-hollow boundary: Based on the coordinate data of the three hollow points of the right-angled triangle face, the area of ​​the current right-angled triangle face is calculated step by step as the tapping operation is performed; Accumulated calculation of void area: The void areas at the void boundary and the void areas at the non-void boundary are accumulated to obtain the void area of ​​the standard working rectangular surface at the current hovering point.

6. A system for calculating the void area of ​​a building inspection drone, characterized in that, Includes the following: Module: Used to construct the drone flight operation coordinate plane: Construct an operation coordinate plane parallel to the building surface at a certain safe distance outside the building surface to be inspected for air bubbles, so that the drone will hover and fly over the operation coordinate plane; Setting module: Used to set the standards for the tapping detection operation, including: Step S21, defining the square coverage area that the UAV can perform tapping detection on the building surface at each hovering flight point as the standard operation rectangle, setting the length and width of the standard operation rectangle and the spacing between tapping points, and arranging each tapping point along the horizontal and vertical directions of the standard operation rectangle according to the spacing between tapping points; Step S22, using a pre-built coordinate transformation model, determining the extension length and angle of the robotic arm under each tapping point condition, and updating the corresponding transformation coordinate relationship between the coordinate parameters of each tapping point and the spatial coordinate parameters of the UAV flight. The detection and calculation module is used to plan the hovering points and flight paths of the UAV on the operational coordinate plane. The horizontal spacing between hovering points is based on the length of the standard operational rectangle, and the vertical spacing is based on the width of the standard operational rectangle. Hovering flight tasks are performed on each hovering point one by one according to the preset flight path. At each hovering point, a tapping detection operation is performed to obtain the coordinate data and hollow points of each tapping point. The area of ​​the hollow points is then calculated by summing these data. The specific processing flow of the tapping detection operation is as follows: Determine the current tapping point: Based on the initial tapping point of the standard operation rectangle and the current hovering point, skip the previous tapping points that have already been tapped at the previous hovering point on the outer perimeter of the standard operation rectangle, and determine the current tapping point where the tapping operation will be performed at the current hovering point. Obtain the coordinates of the current tapping point: Based on the coordinates of the current hovering point, use the coordinate transformation model to obtain the coordinates of each current tapping point; Tapping point detection and judgment: At the current hovering point, tapping trajectory is followed horizontally row by row or vertically column by column. Tapping detection is performed on the current tapping point of the standard working rectangle one by one. Tapping data of each current tapping point is obtained in sequence, and it is determined whether the current tapping point is a hollow point. Calculate the hollow area of ​​the standard operation rectangular surface: Based on the coordinate data of the hollow points at the current hovering point, as the tapping operation is performed, the area of ​​the triangle enclosed by the three adjacent hollow points is calculated step by step, and then the areas are accumulated to obtain the hollow area of ​​the standard operation rectangular surface at the current hovering point. Statistics module: Used to calculate and merge the hollow areas of the standard rectangular surfaces at each hovering point to obtain the hollow area of ​​the building surface to be inspected.

7. The system for calculating the void area of ​​a building inspection drone according to claim 6, characterized in that: The processing procedure of the coordinate transformation model of the setting module is as follows: Based on the set length and width of the standard working rectangle and the safe distance of the working coordinate plane, the extension length and angle of the UAV robotic arm under the condition that the four vertices of the standard working rectangle are used as the striking points are determined; then, based on the set spacing between the striking points, the extension length and angle of the robotic arm under each striking point are determined; then, based on the extension length and angle of the robotic arm under each striking point and the safe distance of the working coordinate plane, the corresponding transformed coordinate relationship between the coordinate parameters of each striking point and the spatial coordinate parameters of the UAV flight is obtained.

8. The system for calculating the void area of ​​a building inspection drone according to claim 7, characterized in that: The processing steps of the coordinate transformation model of the setting module are as follows: taking one of the four vertices of the standard operation rectangular surface as a reference point, the extension length and angle of the robotic arm under each striking point are checked, and the checked transformed coordinate relationship of each striking point is updated.

9. A system for calculating the void area of ​​a building inspection drone according to claim 6, characterized in that: The tapping detection operation of the detection calculation module also includes a re-inspection mode. In this mode, the processing flow for calculating the hollow area of ​​the standard operation rectangular surface is as follows: determine whether there is a hollow boundary in the right-angled triangle formed by three of the four current tapping points covered by two adjacent rows and two columns; if there is a hollow boundary, tapping detection is performed in the area between the hollow points and solid points of the current right-angled triangle surface according to the re-inspection interval. Then, based on the coordinate data of the hollow points of the current hovering point, as the tapping operation is performed, the area of ​​the triangle formed by the three adjacent hollow points of the current right-angled triangle surface is calculated step by step; otherwise, the area of ​​the current right-angled triangle surface is calculated step by step, and then the results are accumulated to obtain the hollow area of ​​the standard operation rectangular surface at the current hovering point.

10. A system for calculating the void area of ​​a building inspection drone according to claim 9, characterized in that: The specific processing flow for calculating the hollow area of ​​the standard rectangular surface in the tapping test operation of the detection calculation module in the re-inspection mode is as follows: Determine the boundary of hollow areas: Mark each current tapping point as either a hollow point or a solid point. In real time, determine whether there is a hollow boundary in the right triangle formed by three of the four current tapping points covered by two adjacent rows and two columns. If both hollow and solid points exist in the three current tapping points of the right triangle, it is determined that there is a hollow boundary in the current right triangle and the hollow area of ​​the hollow boundary is calculated. Otherwise, there is no hollow boundary and the hollow area of ​​the non-hollow boundary is calculated. Calculate the area of ​​the hollow area at the boundary of the hollow area: Arrange preliminary inspection points along the horizontal and vertical directions at re-inspection intervals on the edge and inner perimeter of the current right-angled triangle face. Then, determine the preliminary inspection points on the line connecting the vertices of the hollow points and the solid points of the right-angled triangle face as the tapping re-inspection points. Perform tapping detection on each preliminary inspection point or tapping re-inspection point of the current right-angled triangle face, sequentially acquiring the tapping data of each preliminary inspection point or tapping re-inspection point, and determine whether the preliminary inspection point or tapping re-inspection point is a hollow point based on this data. Based on the current hovering point coordinate data, use a coordinate transformation model to obtain the coordinate data of each preliminary inspection point or tapping re-inspection point. Based on the re-inspection point coordinate data, as the tapping operation is performed, progressively calculate the area of ​​the triangle enclosed by the three adjacent hollow points of the current right-angled triangle face, and then sum them to obtain the area of ​​the hollow area of ​​the current right-angled triangle face. The tapping point spacing is an integer multiple of the re-inspection interval. Calculate the area of ​​the hollow area at the non-hollow boundary: Based on the coordinate data of the three hollow points of the right-angled triangle face, the area of ​​the current right-angled triangle face is calculated step by step as the tapping operation is performed; Accumulated calculation of void area: The void areas at the void boundary and the void areas at the non-void boundary are accumulated to obtain the void area of ​​the standard working rectangular surface at the current hovering point.

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