Truck height intelligent detection and height limit mark linkage early warning system

Abstract

The invention discloses a freight car height intelligent detection and height limit sign linkage early warning system, which belongs to the technical field of detection early warning, and comprises a gantry support with a laser sensing device, an acquisition machine, an early warning system and a height limit sign with a display screen and an acousto-optic broadcaster, the laser sensing devices on the gantry support are arranged to be a detection point a directly facing a detection area and a detection point b inclining towards the driving direction, the angle between the detection point a and the detection point b is alpha, and the height limiting mark is located behind the detection area. Detection data which are recorded, stored, converted and separated are calculated through a height detection algorithm and a length detection algorithm to obtain the height, the length and the width of a corresponding vehicle passing through a detection area, and then the height, the length and the width of the vehicle are compared and judged according to a pre-passing height limiting area to meet passing limitation. And a display screen and an acousto-optic broadcaster are adopted to warn a driver of the vehicle to detour timely according to the result.

Description

Technical Field

[0001] The invention discloses a detection and early warning technology, and in particular relates to an intelligent truck height detection and height limit sign linkage early warning system. Background Art

[0002] Many highway tunnels and bridges have height restrictions, but accidents often occur due to the lack of warning effect of traditional height restriction signs, drivers' lack of concentration or unfamiliarity with height restriction sections, etc. These accidents often lead to traffic congestion, public property losses and casualties.

[0003] For this purpose, a height limit warning system has emerged. When a passing vehicle passes through a tunnel or a highway bridge with a restricted height, the height limit warning system promptly reminds the driver to react and take action. However, most existing height limit warning systems only use voice broadcasts or strong lights to remind passing vehicles that the next section of the road is a restricted height area. However, this method can only have a reminder function, and cannot distinguish vehicles that cannot pass and avoid them by detours. In addition, for areas with narrow lanes such as culverts and bridge holes, not only is it necessary to limit the height, but it is also difficult for trucks with long bodies to pass and turn due to the narrow corner exits. However, the existing height limit warning system does not have this function. Summary of the invention

[0004] The purpose of the present invention is to solve the above-mentioned problems and to provide a truck height intelligent detection and height limit sign linkage warning system.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a truck height intelligent detection and height limit sign linkage warning system, comprising a gantry bracket with a laser sensor device, a collector, a warning system and a height limit sign with a display screen and an audio and video announcer, the lower part of the gantry bracket is set as a vehicle detection area, the laser sensor device on the gantry bracket is arranged as a detection point a facing the detection area and a detection point b inclined in the driving direction, the angle between the detection point a and the detection point b is α, the height limit sign is located behind the detection area, and a height detection algorithm and a length detection algorithm are provided between the laser sensor device and the collector, and the detection steps are as follows: Ⅰ. The laser sensor device collects the detection data of the vehicle passing by in a pulsed manner. In the height detection algorithm, a height threshold is set As the judgment test value, when the test data detected at the a test point is greater than When a vehicle enters the detection area, the acquisition machine converts and separates the multiple groups of detection data collected by the laser sensor device into multiple groups of height sequence values ​​and relative displacement sequence values, extracts the maximum value in each height sequence, takes the maximum value in the multiple groups of height sequences as the final height output, and records and saves each group of height sequence values ​​and relative displacement sequence values; Ⅱ, when the detection data detected by detection point b and detection point a are both greater than When the vehicle has passed the detection area, it is determined that the vehicle has passed the detection area. In the length detection algorithm, the height waveforms in the detection data collected by the pulse are intelligently compared, and the span time T with the largest degree of similarity in the height waveforms compared pairwise is obtained. The largest span time T is used as the search period to reversely search for the relative displacement value of the vehicle in the span time in multiple groups of relative displacement sequence values, and the multiple relative displacement values ​​found are accumulated as the final length output; III. The warning system compares the output final height and final length with the preset limit height and limit length. If the limit height and limit length are exceeded, the display screen and the sound and light announcer are controlled to warn the driver of the vehicle.

[0006] As a preferred embodiment, in the acquisition machine and the early warning system, the acquisition machine performs coordinate system conversion on the collected detection data, and the conversion method is as follows: S1, when the laser sensor device outputs detection data in the form of a coordinate system (x, y, z), the rotation matrix R and the translation matrix t are used to describe the transformation between the coordinate system and the real world coordinate system. Suppose any point p in space, the transposed matrix of the homogeneous coordinates of p in the world coordinate system is , in the collector it is , the conversion relationship is as follows: ; Among them, R is a 3×3 unit orthogonal transformation matrix, t is a 3×1 translation matrix, is a 3×1 zero matrix, is a 4×4 matrix; S2, let the projection coordinates of point p be (u, v), and assume a projection o, whose projection coordinates are , the corresponding projection coordinates in the pixel coordinate sizes of the output graphic data are dx and dy respectively. The relationship between the pixel coordinates and the coordinate system is as follows: ; ; ; in, , is the relevant lens angle parameter of the laser sensor device; Substituting the relations in S3, S1 and S2, we can get the coordinate relation between the coordinates of point p in the real world coordinate system and the projection point of point p as follows: ; Where s is the proportional constant factor, M is the 3×3 projection matrix, is the focal length parameter of the relevant lens of the laser sensor device.

[0007] Preferably, in the early warning system, the calculation steps of the height detection algorithm are as follows: K1, let the polar diameter of each scanning point reflected back from the surface of the measured vehicle be ρ, and the corresponding polar angle θ∈ , where m is the number of scanning points of the laser sensor device in one scanning cycle, is the starting angle value output by the laser sensor device, is the end angle value output by the laser sensor device, the coordinate system relationship conversion formula is x=ρcosθ, y=ρsinθ, then the horizontal distance calculation formula from the scanning point to the laser sensor device is x(m)=|ρ(m)cosθ|, the vertical distance from the scanning point to the laser sensor is calculated as y(m)=ρ(m)sinθ; Among them, ρ (m) is the polar diameter corresponding to each scanning point; K2, if y(m) is less than , the collected test data is deemed valid and saved until the multiple sets of test data detected are simultaneously greater than Stop saving the collected test data; K3, the vehicle height value is calculated as follows: h(m)=Hy(m); l(m)=lx(m); Wherein, H is the vertical distance from the scanning point of the laser sensor device to the ground of the detection area, h (m) is the height value of the scanning point on the detection vehicle, l is the horizontal distance of the laser sensor device within the initial angle range, and l (m) is the horizontal distance of the laser sensor device within the α angle range; K4, select the maximum value of the height component within a scanning cycle to obtain the height of the vehicle.

[0008] Preferably, in the early warning system, the calculation formula of the length detection algorithm is as follows: ; Where K is the number of scan crosses, the number of translations of the midpoint of the pixel coordinates generated by the laser sensor scanning point, and each translation component angle corresponds to 0.5°; is the relative displacement sequence value corresponding to the i-th group α angle scan, The relative displacement sequence value corresponding to the α+0.5*K angle scan in the i+1th group of relative displacement sequence values ​​is accumulated to obtain the length of the vehicle.

[0009] Compared with the prior art, the present invention has the following beneficial effects: By setting up laser sensors and detection areas, vehicles that are expected to pass through height-restricted areas such as culverts or bridge tunnels are pre-detected. The detection data collected by the laser sensor is converted and separated into multiple groups of height sequence values ​​and relative displacement sequence values ​​by a data collector, and the maximum value in each height sequence is extracted. The maximum value in the multiple groups of height sequences is taken as the final output height, and each group of height sequence values ​​and relative displacement sequence values ​​is recorded and saved. The height detection algorithm and the length detection algorithm are enabled to calculate the recorded and converted detection data to obtain the corresponding vehicle height, length and width passing through the detection area. The height, length and width of the vehicle are then compared with the height-restricted area that is expected to pass through to determine whether it meets the traffic restrictions. According to the results, a display screen and an audio-visual announcer are used to warn the driver of the vehicle to take a detour in time. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a schematic diagram showing the positions of the gantry bracket, laser sensor device and height limit sign; Figure 2 It is a schematic diagram showing the principle of the height detection algorithm; Figure 3 This is a simplified diagram to illustrate the situation when the exit road of the culvert or bridge tunnel for vehicles to pass through is a narrow curve and the culvert or bridge tunnel is narrow.

[0011] Figure numerals: 1. gantry bracket; 2. height limit sign; 3. laser sensor device. DETAILED DESCRIPTION

[0012] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0013] A truck height intelligent detection and height limit sign linkage warning system, such as Figure 1As shown, it includes a gantry support 1 with a laser sensor device 3, a collector, an early warning system and a height limit sign 2 with a display screen and an audio and video announcer. The lower part of the gantry support 1 is set as a vehicle detection area. The laser sensor device 3 on the gantry support 1 is arranged as a detection point a facing the detection area and a detection point b inclined in the driving direction. The angle between the detection point a and the detection point b is α. The height limit sign 2 is located behind the detection area. There is a height detection algorithm and a length detection algorithm between the laser sensor device 3 and the collector. The detection steps are as follows: Ⅰ. The laser sensor device 3 collects the detection data of the vehicle passing by in a pulsed manner. In the height detection algorithm, a height threshold is set As the judgment test value, when the test data detected at the a test point is greater than When it is determined that a vehicle has entered the detection area, the acquisition machine converts and separates the multiple groups of detection data collected by the laser sensor device 3 into multiple groups of height sequence values ​​and relative displacement sequence values, extracts the maximum value in each height sequence, takes the maximum value in the multiple groups of height sequences as the final height output, and records and saves each group of height sequence values ​​and relative displacement sequence values; like Figure 2 As shown, in the early warning system, the calculation steps of the height detection algorithm are as follows: K1, let the polar diameter of each scanning point reflected back from the surface of the measured vehicle be ρ, and the corresponding polar angle θ∈ , where m is the number of scanning points of the laser sensor device 3 in one scanning cycle, is the starting angle value output by the laser sensor device 3, is the end angle value output by the laser sensor device 3, the coordinate system relationship conversion formula is x=ρcosθ, y=ρsinθ, then the horizontal distance calculation formula from the scanning point to the laser sensor device 3 is x(m)=|ρ(m)cosθ|, the vertical distance from the scanning point to the laser sensor device 3 is calculated as y(m)=ρ(m)sinθ; Among them, ρ (m) is the polar diameter corresponding to each scanning point; K2, if y(m) is less than , the collected test data is deemed valid and saved until the multiple sets of test data detected are simultaneously greater than Stop saving the collected test data; K3, the vehicle height value is calculated as follows: h(m)=Hy(m); l(m)=lx(m); Wherein, H is the vertical distance from the scanning point of the laser sensor device 3 to the ground of the detection area, h (m) is the height value of the scanning point on the detection vehicle, l is the horizontal distance of the laser sensor device 3 within the initial angle range, and l (m) is the horizontal distance of the laser sensor device 3 within the α angle range; K4, select the maximum value of the height component within a scanning cycle to obtain the height of the vehicle; Ⅱ, when the detection data detected by detection point b and detection point a are both greater than When the vehicle has passed the detection area, it is determined that the vehicle has passed the detection area. In the length detection algorithm, the height waveforms in the detection data collected by the pulse are intelligently compared, and the span time T with the largest degree of similarity in the height waveforms compared pairwise is obtained. The largest span time T is used as the search period to reversely search for the relative displacement value of the vehicle in the span time in multiple groups of relative displacement sequence values, and the multiple relative displacement values ​​found are accumulated as the final length output; In the early warning system, Figure 1 As shown, the calculation formula of the length detection algorithm is as follows: ; Wherein, K is the number of scanning crosses, the number of translations of the midpoint of the pixel coordinates generated by the scanning point of the laser sensor device 3, and each translation component angle corresponds to 0.5°; is the relative displacement sequence value corresponding to the i-th group α angle scan, is the relative displacement sequence value corresponding to the α+0.5*K angle scan in the i+1th group of relative displacement sequence values, and the length of the vehicle is obtained by accumulating the multiple relative displacement values ​​found; like Figure 3 As shown, if the culvert or bridge tunnel exit road is a narrow curve and the culvert or bridge tunnel is narrow, even if the height of the vehicle does not exceed the height limit, the vehicle cannot pass because the length and width of the vehicle body limit the turning angle range of the vehicle. Therefore, it is necessary to detect the length and width of the vehicle as well, wherein the width detection can be improved in the same way as the length detection algorithm, but another set of laser sensor devices 3 (not shown in the figure) are installed on both sides of the gantry to obtain the width data of the vehicle. Then, the early warning system simulates that the vehicle body can reach the narrow curve exit road through the culvert or bridge tunnel within the limited width and length while meeting the height limit.

[0014] III. The warning system compares the output final height and final length with the preset limit height and limit length. If the limit height and limit length are exceeded, the display screen and the sound and light announcer are controlled to warn the driver of the vehicle; In the acquisition machine and early warning system, the acquisition machine performs coordinate system conversion on the collected detection data. The conversion method is as follows: S1, when the laser sensor device 3 outputs the detection data in the form of a coordinate system (x, y, z), the rotation matrix R and the translation matrix t are used to describe the transformation between the coordinate system and the real world coordinate system. Suppose that the homogeneous coordinates of any point p in the space, the transposed matrix of p in the world coordinate system is , in the collector it is , the conversion relationship is as follows: ; Among them, R is a 3×3 unit orthogonal transformation matrix, t is a 3×1 translation matrix, is a 3×1 zero matrix, is a 4×4 matrix; S2, let the projection coordinates of point p be (u, v), and assume a projection o, whose projection coordinates are , the corresponding projection coordinates in the pixel coordinate sizes of the output graphic data are dx and dy respectively. The relationship between the pixel coordinates and the coordinate system is as follows: ; ; ; in, , is the relevant lens angle parameter of the laser sensor device 3; Substituting the relations in S3, S1 and S2, we can get the coordinate relation between the coordinates of point p in the real world coordinate system and the projection point of point p as follows: ; Where s is the proportional constant factor, M is the 3×3 projection matrix, is the relevant lens focal length parameter of the laser sensor device 3.

[0015] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0016] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A truck height intelligent detection and height limit sign linkage warning system, characterized by: The invention comprises a gantry support (1) with a laser sensor device (3), a collection machine, an early warning system and a height limit sign (2) with a display screen and an audio and video announcer, wherein the lower part of the gantry support (1) is set as a vehicle detection area, the laser sensor device (3) on the gantry support (1) is arranged as a detection point a facing the detection area and a detection point b inclined in the driving direction, the angle between the detection point a and the detection point b is α, the height limit sign (2) is located behind the detection area, and a height detection algorithm and a length detection algorithm are provided between the laser sensor device (3) and the collection machine, and the detection steps are as follows: Ⅰ. The laser sensor device (3) collects the detection data of the vehicle passing by in a pulsed manner. In the height detection algorithm, a height threshold is set. As the judgment test value, when the test data detected at the a test point is greater than When a vehicle enters the detection area, the acquisition machine converts and separates the multiple groups of detection data collected by the laser sensor device (3) into multiple groups of height sequence values ​​and relative displacement sequence values, extracts the maximum value in each height sequence, takes the maximum value in the multiple groups of height sequences as the final height output, and records and stores each group of height sequence values ​​and relative displacement sequence values; Ⅱ, when the detection data detected by detection point b and detection point a are both greater than When the vehicle has passed the detection area, it is determined that the vehicle has passed the detection area. In the length detection algorithm, the height waveforms in the detection data collected by the pulse are intelligently compared, and the span time T with the largest degree of similarity in the height waveforms compared pairwise is obtained. The largest span time T is used as the search period to reversely search for the relative displacement value of the vehicle in the span time in multiple groups of relative displacement sequence values, and the multiple relative displacement values ​​found are accumulated as the final length output; III. The warning system compares the output final height and final length with the preset limit height and limit length. If the limit height and limit length are exceeded, the display screen and the sound and light announcer are controlled to warn the driver of the vehicle.

2. According to claim 1, a truck height intelligent detection and height limit sign linkage warning system is characterized by: In the acquisition machine and early warning system, the acquisition machine performs coordinate system conversion on the collected detection data. The conversion method is as follows: S1, when the laser sensor device (3) outputs detection data in the form of a coordinate system (x, y, z), the rotation matrix R and the translation matrix t are used to describe the transformation between the coordinate system and the real world coordinate system. Suppose that the homogeneous coordinates of any point p in the space, the transposed matrix of p in the world coordinate system is , in the collector it is , the conversion relationship is as follows: ； Among them, R is a 3×3 unit orthogonal transformation matrix, t is a 3×1 translation matrix, is a 3×1 zero matrix, is a 4×4 matrix; S2, let the projection coordinates of point p be (u, v), and assume a projection o, whose projection coordinates are , the corresponding projection coordinates in the pixel coordinate sizes of the output graphic data are dx and dy respectively. The relationship between the pixel coordinates and the coordinate system is as follows: ； ； ； in, , is the relevant lens angle parameter of the laser sensor device (3); Substituting the relations in S3, S1 and S2, we can get the coordinate relation between the coordinates of point p in the real world coordinate system and the projection point of point p as follows: ； Where s is the proportional constant factor, M is the 3×3 projection matrix, is the relevant lens focal length parameter of the laser sensor device (3).

3. The intelligent truck height detection and height limit sign linkage warning system according to claim 2 is characterized by: In the early warning system, the calculation steps of the height detection algorithm are as follows: K1, let the polar diameter of each scanning point reflected back from the surface of the measured vehicle be ρ, and the corresponding polar angle θ∈ , where m is the number of scanning points of the laser sensor device (3) in one scanning cycle, is the starting angle value output by the laser sensor device (3), is the end angle value output by the laser sensor device (3), the coordinate system relationship conversion formula is x=ρcosθ, y=ρsinθ, then the horizontal distance calculation formula from the scanning point to the laser sensor device (3) is x(m)=|ρ(m)cosθ|, the vertical distance from the scanning point to the laser sensor device (3) is calculated as y(m)=ρ(m)sinθ; Among them, ρ (m) is the polar diameter corresponding to each scanning point; K2, if y(m) is less than , the collected test data is deemed valid and saved until the multiple sets of test data detected are simultaneously greater than Stop saving the collected test data; K3, the vehicle height value is calculated as follows: h(m)=Hy(m); l(m)=lx(m); Wherein, H is the vertical distance from the scanning point of the laser sensor device (3) to the ground of the detection area, h (m) is the height value of the scanning point on the detection vehicle, l is the horizontal distance of the laser sensor device (3) within the initial angle range, and l (m) is the horizontal distance of the laser sensor device (3) within the α angle range; K4, select the maximum value of the height component within a scanning cycle to obtain the height of the vehicle.

4. The intelligent truck height detection and height limit sign linkage warning system according to claim 3 is characterized by: In the early warning system, the calculation formula of the length detection algorithm is as follows: ； Wherein, K is the number of scanning crosses, the number of translations of the midpoint of the pixel coordinates generated by the scanning point of the laser sensor device (3), and each translation component angle corresponds to 0.5°; is the relative displacement sequence value corresponding to the i-th group α angle scan, The relative displacement sequence value corresponding to the α+0.5*K angle scan in the i+1th group of relative displacement sequence values ​​is accumulated to obtain the length of the vehicle.

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