Cable force detection method of bridge inhaul cable based on unmanned aerial vehicle and millimeter wave radar

Abstract

The invention relates to a cable force detection method for a bridge cable based on an unmanned aerial vehicle and a millimeter-wave radar, and the method comprises the following steps: providing the unmanned aerial vehicle and the millimeter-wave radar, and installing the provided millimeter-wave radar on the unmanned aerial vehicle; controlling the unmanned aerial vehicle to fly and stop at a position close to a to-be-detected bridge cable; adjusting the measurement angle of the millimeter-wave radar, enabling the measurement range of the millimeter-wave radar and the to-be-detected bridge cable to form a set angle, and detecting the to-be-detected bridge cable by using the millimeter-wave radar to obtain detection data; and processing the detection data to obtain the cable force of the bridge cable. The non-contact cable force detection of the bridge cable is realized, the unmanned aerial vehicle carries the millimeter wave radar to fly and stop in the air to realize detection, so that the bridge traffic does not need to be closed, the normal use of the bridge is not influenced, the detection process is simple and convenient, and the detection efficiency can be effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of cable force detection, and in particular to a cable force detection method for a bridge cable based on an unmanned aerial vehicle and a millimeter wave radar. Background Art

[0002] The existing bridge cable force detection method mostly uses the vibration frequency method for detection, using a high-precision vibration pickup sensor, which is installed on the corresponding bridge cable, contacts the bridge cable, picks up the vibration response of the bridge cable, and then calculates the bridge cable force result. This measurement method requires the bridge cables to be measured one by one, and each measurement requires the vibration pickup sensor to be installed on the bridge cable. After the detection is completed, the vibration pickup sensor is removed, making the detection process more complicated. For a bridge in use, the above detection method also requires the traffic on the bridge to be closed, which brings inconvenience to the use of the bridge. Summary of the invention

[0003] The purpose of the present invention is to overcome the defects of the prior art and provide a method for detecting the cable force of a bridge cable based on an unmanned aerial vehicle and a millimeter-wave radar, so as to solve the problems that the existing method of detecting the cable force of a bridge cable by a vibration pickup sensor has the disadvantages of complex operation, low detection efficiency and the need to close the bridge for traffic.

[0004] The technical solution to achieve the above purpose is:

[0005] The present invention provides a method for detecting the cable force of a bridge cable based on an unmanned aerial vehicle and a millimeter wave radar, comprising the following steps:

[0006] Providing a drone and a millimeter-wave radar, and installing the provided millimeter-wave radar on the drone;

[0007] Controlling the UAV to fly and stop at a position close to the bridge cable to be inspected;

[0008] Adjusting the measuring angle of the millimeter wave radar so that the measuring range of the millimeter wave radar forms a set angle with the bridge cable to be detected, and using the millimeter wave radar to detect the bridge cable to be detected to obtain detection data;

[0009] The detection data is processed to obtain the cable force of the bridge cable.

[0010] A further improvement of the bridge cable force detection method based on a drone and a millimeter wave radar of the present invention is that the step of controlling the drone to fly and stop at a position close to the bridge cable to be detected comprises:

[0011] The UAV is controlled to fly and stop above the bridge cables, and the millimeter wave radar is allowed to detect all the bridge cables to be detected at an oblique downward measurement angle.

[0012] A further improvement of the bridge cable force detection method based on an unmanned aerial vehicle and a millimeter wave radar of the present invention is that before the bridge cable is detected by the millimeter wave radar, an inclined reflector is arranged at a corresponding position on the bridge panel.

[0013] The present invention further improves the bridge cable force detection method based on drone and millimeter wave radar, and further includes:

[0014] Providing an acceleration sensor, and installing the provided acceleration sensor on the drone;

[0015] During the flying and stopping process of the UAV, the acceleration sensor is used to detect the vibration of the UAV to obtain vibration data;

[0016] When processing the detection data, the influence of the vibration data is removed from the detection data, and then the cable force of the bridge cable is calculated.

[0017] A further improvement of the bridge cable force detection method based on an unmanned aerial vehicle and a millimeter wave radar of the present invention is that when the bridge cable to be detected is detected by using the millimeter wave radar, the detection time of the millimeter wave radar is controlled to be 5 minutes.

[0018] A further improvement of the bridge cable force detection method based on an unmanned aerial vehicle and a millimeter-wave radar of the present invention is that when adjusting the measurement angle of the millimeter-wave radar, the setting direction of the bridge cable located in the middle is used as a reference, so that the measurement angle of the millimeter-wave radar is perpendicular to the setting direction of the bridge cable located in the middle.

[0019] A further improvement of the bridge cable force detection method based on an unmanned aerial vehicle and a millimeter wave radar of the present invention is that when the millimeter wave radar is used for detection, the measurement range of the millimeter wave radar covers all bridge cables.

[0020] A further improvement of the bridge cable force detection method based on a drone and a millimeter wave radar of the present invention is that the step of controlling the drone to fly and stop at a position close to the bridge cable to be detected comprises:

[0021] The UAV is controlled to fly and stop below the bridge cables, and the millimeter wave radar is allowed to detect all the bridge cables to be detected at an oblique upward measurement angle.

[0022] The beneficial effects of the bridge cable force detection method based on drone and millimeter wave radar of the present invention are:

[0023] The present invention realizes non-contact cable force detection of bridge cables through unmanned aerial vehicles and millimeter wave radars. The unmanned aerial vehicles carry millimeter wave radars and fly and stop in the air to realize detection, so that the bridge traffic does not need to be closed and the normal use of the bridge is not affected. The detection process is simple and convenient, which can effectively improve the detection efficiency.

[0024] The UAV of the present invention carries a millimeter-wave radar and flies and stops above the bridge cables to detect the bridge cables from top to bottom. The millimeter-wave radar is used to directly observe the dynamic displacement of the bridge cables, that is, the displacement of the bridge cables on the vertical plane. The bridge cables located at the upper part are longer and their dynamic displacement changes are also larger. The detection is carried out from above the millimeter-wave radar, which is closer to the upper bridge cables, and can improve the accuracy of the detection results.

[0025] The present invention realizes one-time measurement of a fixed point through the millimeter wave radar, and can complete the detection of all bridge cables at one time, with convenient operation and high efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the detection process in the bridge cable force detection method based on unmanned aerial vehicle and millimeter wave radar of the present invention.

[0027] Figure 2 It is a structural schematic diagram of another detection process of the bridge cable force detection method based on unmanned aerial vehicle and millimeter wave radar of the present invention.

[0028] Figure 3 This is an architectural diagram of the detection data transmission in the bridge cable force detection method based on drone and millimeter wave radar of the present invention.

[0029] Figure 4 The present invention is a flow chart of a bridge cable force detection method based on an unmanned aerial vehicle and a millimeter wave radar. DETAILED DESCRIPTION

[0030] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0031] See also Figure 1 The present invention provides a bridge cable force detection method based on an unmanned aerial vehicle and a millimeter-wave radar. The unmanned aerial vehicle carrying the millimeter-wave radar is used to perform non-contact cable force detection on the bridge cable at high altitude. The millimeter-wave radar can directly observe the dynamic displacement of the bridge cable, and then obtain the corresponding spectrum diagram by processing the dynamic displacement data, thereby realizing the cable force detection of the bridge cable. The detection method of the present invention does not need to close the bridge to traffic, and its detection will not affect the normal use of the bridge. The detection method of the present invention has high detection efficiency and high detection accuracy. The cable force detection method of the bridge cable based on an unmanned aerial vehicle and a millimeter-wave radar of the present invention is described below in conjunction with the accompanying drawings.

[0032] See also Figure 4 , showing a flow chart of the bridge cable force detection method based on drone and millimeter wave radar of the present invention. Figure 4 , the cable force detection method of the bridge cable based on the UAV and the millimeter wave radar of the present invention is explained.

[0033] like Figure 4 As shown, the bridge cable force detection method based on drone and millimeter wave radar of the present invention comprises the following steps:

[0034] Execute step S101, provide a drone and a millimeter wave radar, and install the provided millimeter wave radar on the drone; then execute step S102;

[0035] Execute step S102 to control the drone to fly and stop at a position close to the bridge cable to be inspected; then execute step S103;

[0036] Execute step S103, adjust the measurement angle of the millimeter wave radar, make the measurement range of the millimeter wave radar and the bridge cable to be detected form a set angle, use the millimeter wave radar to detect the bridge cable to be detected, and obtain detection data; then execute step S104;

[0037] Step S104 is executed to process the detection data to obtain the cable force of the bridge cable.

[0038] like Figure 1 As shown, the present invention uses a millimeter wave radar 30 to detect the vibration displacement of the bridge cable 13 at a fixed point in the air. The detection data obtained is the vibration displacement data of the bridge cable 13. The vibration displacement data is processed by an FFT algorithm to obtain a corresponding frequency spectrum of the bridge cable, thereby realizing non-contact and long-distance monitoring of the bridge cable force.

[0039] A column 12 is erected on the bridge deck 11, and bridge cables 13 are arranged on both sides of the column 12. There are many bridge cables 13, and they are all arranged in an inclined shape. If the column 12 is erected in the middle of the bridge deck 11, the other ends of the bridge cables 13 on both sides of the column 12 are connected to the bridge deck 11. If the column 12 is erected at one end of the bridge deck 11, the other end of the bridge cable 13 on one side of the column 12 is connected to the bridge deck 11, and the other end of the bridge cable 13 on the other side of the column 12 is connected to the ground at the end of the bridge deck 11.

[0040] The detection method of the present invention can be used to detect the bridge cables 13 on both sides of the column 12. During the detection, the drone 20 is used to fly and stop in the air, and the millimeter-wave radar 30 is used to scan and detect the bridge cables 13 on one side of the column 12. The millimeter-wave radar 30 transmits radar waves to the bridge cables 13. After encountering the bridge cables 13, the radar waves are reflected back to the millimeter-wave radar 30 and are received by the receiving device on the millimeter-wave radar 30. Therefore, the distance between the millimeter-wave radar 30 and the corresponding bridge cable 13 can be obtained through the emission and return of the radar waves. The vibration of the bridge cable 13, that is, the vibration on the vertical plane, can be obtained through the distance data over a period of time. Then, the cable force of the bridge cable can be calculated based on the vibration condition, thereby realizing the monitoring of the cable force.

[0041] In a specific embodiment of the present invention, the step of controlling the drone 20 to fly and stop at a position close to the bridge cable 13 to be inspected includes:

[0042] The drone 20 is controlled to fly and stop above the bridge cables 13, and the millimeter wave radar 30 is allowed to detect all the bridge cables 13 to be detected at an oblique downward measurement angle.

[0043] The drone 20 flies to the top of the bridge cable 13 and hovers, and then adjusts the measuring angle of the probe of the millimeter wave radar 30 so that the measuring range of the millimeter wave radar 30 is at a set angle with the bridge cable to be detected, and the set angle range is between 60° and 120°.

[0044] Furthermore, the measurement range of the millimeter wave radar 30 is in a cone shape, and when the millimeter wave radar 30 is used for detection, the measurement range of the millimeter wave radar 30 covers all bridge cables 13. The measurement of the bridge cables 13 is completed at one time, and the measurement efficiency is improved.

[0045] Furthermore, the drone 20 is provided with a gimbal, and the millimeter-wave radar 30 is installed on the gimbal, and the detection angle of the probe of the millimeter-wave radar 30 is adjusted by the gimbal.

[0046] The millimeter-wave radar 30 of the present invention scans and measures the bridge cable 13 from top to bottom. The length of the bridge cable 13 at the upper part is longer than that of the bridge cable 13 at the lower part. The cable force of the bridge cable 13 at the upper part is also greater than that of the bridge cable 13 at the lower part. The vibration displacement of the bridge cable 13 at the upper part is greater than that of the bridge cable 13 at the lower part. In this way, the millimeter-wave radar 30 performs detection from top to bottom, and is closer to the bridge cable 13 at the upper part, so that the change of the vibration displacement of the bridge cable 13 at the upper part can be more easily detected, thereby improving the detection accuracy of the bridge cable 13 and making the detection result more accurate.

[0047] Furthermore, before the bridge cable 13 is detected by the millimeter wave radar 30, an inclined reflector 40 is arranged at a corresponding position on the bridge deck 11. The inclined reflector 40 can reflect the radar wave at a set angle, so that the radar wave directed to the bridge deck can be reflected at the set angle and will not be received by the millimeter wave radar 30, thereby avoiding the reflection of the bridge deck 11 from affecting the cable force detection result of the bridge cable 13.

[0048] In a specific embodiment of the present invention, Figure 2 As shown, the steps of controlling the drone 20 to fly and stop at a position close to the bridge cable 13 to be inspected include:

[0049] The drone 20 is controlled to fly and stop below the bridge cables 13, and the millimeter wave radar is allowed to detect all the bridge cables 13 to be detected at an oblique upward measurement angle.

[0050] The drone 20 flies to the bottom of the bridge cable 13 and hovers, and then adjusts the measuring angle of the probe of the millimeter wave radar 30 so that the measuring range of the millimeter wave radar 30 is at a set angle with the bridge cable to be detected, and the set angle range is between 60° and 120°.

[0051] In a specific embodiment of the present invention, the detection method of the present invention further comprises:

[0052] Providing an acceleration sensor, and installing the provided acceleration sensor on the drone 20;

[0053] During the flight and parking of the drone 20, the vibration of the drone 20 is detected by using an acceleration sensor to obtain vibration data;

[0054] When processing the detection data of the millimeter wave radar, the influence of the vibration data is removed from the detection data, and then the cable force of the bridge cable is calculated.

[0055] When the drone 20 is hovering, the rotation of its own wings will cause the drone 20 to vibrate to a certain extent. The displacement change of this vibration phenomenon in the vertical direction will have a certain impact on the detection result of the millimeter-wave radar 30. In order to improve the detection accuracy of the millimeter-wave radar 30, the vibration data of the drone 20 during the flight and landing process is detected by the set acceleration sensor, and then the vibration data is analyzed to obtain the vibration component in the vertical direction. The vibration displacement data detected by the millimeter-wave radar is subtracted from the vibration component in the vertical direction, thereby eliminating the influence of the vibration of the drone itself and improving the detection accuracy.

[0056] In a specific implementation of the present invention, when the millimeter wave radar 30 is used to detect the bridge cable 13 to be detected, the detection time of the millimeter wave radar 30 is controlled to be 5 minutes.

[0057] Furthermore, when adjusting the measuring angle of the millimeter wave radar 30 , the setting direction of the bridge cable 13 located in the middle is taken as a reference, so that the measuring angle of the millimeter wave radar 30 is perpendicular to the setting direction of the bridge cable 13 located in the middle.

[0058] Furthermore, when the drone 20 selects a hovering position, the drone 20 is hovered above the upper 1 / 4 of the topmost bridge cable 13 .

[0059] Furthermore, when the millimeter wave radar 30 is used for detection, the measurement range 31 of the millimeter wave radar 30 covers all bridge cables 31. Here, all bridge cables 31 refer to bridge cables 31 located on the same side.

[0060] If the probe of the millimeter-wave radar 30 is adjusted to be located just within the vertical plane of the bridge cable 31, the millimeter-wave radar 30 can only detect one bridge cable 31 below it. By adjusting the probe of the millimeter-wave radar 30 so that the detection angle or direction of the probe deviates from the vertical plane, the measurement range 31 covers all bridge cables 31, thereby completing the cable force detection of all bridge cables 13 on the same side at one time and improving the detection efficiency.

[0061] In a specific embodiment of the present invention, the detection method of the present invention also includes establishing a data processing system, establishing a local area network between the data processing system and the millimeter wave radar 30 through the Internet of Things system to achieve data transmission, and the detection data detected by the millimeter wave radar 30 in real time can be transmitted to the data processing system in real time through the Internet of Things system.

[0062] The data processing system can process the detection data, for example, by processing the data through the FFT algorithm to obtain the corresponding spectrum diagram, and then display the spectrum diagram in real time through the display, so that the detection personnel can view the spectrum of the bridge cable in real time.

[0063] The detection method of the present invention can solve the problem that the fast lane on the bridge cannot be closed for traffic. It uses drones and millimeter-wave radars to detect the cable tension of the bridge cables, which will not affect the normal use of the bridge, can achieve rapid detection, and improve on-site work efficiency.

[0064] The detection direction of the present invention realizes the extension of low-altitude economy in the field of bridge monitoring.

[0065] The present invention is described in detail above in conjunction with the embodiments of the accompanying drawings. A person skilled in the art can make various variations of the present invention according to the above description. Therefore, certain details in the embodiments should not constitute a limitation of the present invention, and the scope of protection of the present invention shall be defined by the scope of the attached claims.

Claims

1. A bridge cable force detection method based on drone and millimeter wave radar, characterized in that: The steps include: Providing a drone and a millimeter-wave radar, and installing the provided millimeter-wave radar on the drone; Controlling the UAV to fly and stop at a position close to the bridge cable to be inspected; Adjusting the measuring angle of the millimeter wave radar so that the measuring range of the millimeter wave radar forms a set angle with the bridge cable to be detected, and using the millimeter wave radar to detect the bridge cable to be detected to obtain detection data; The detection data is processed to obtain the cable force of the bridge cable.

2. The bridge cable force detection method based on drone and millimeter wave radar as claimed in claim 1 is characterized in that: The steps of controlling the drone to fly and stop at a position close to the bridge cable to be inspected include: The UAV is controlled to fly and stop above the bridge cables, and the millimeter wave radar is allowed to detect all the bridge cables to be detected at an oblique downward measurement angle.

3. The bridge cable force detection method based on drone and millimeter wave radar as claimed in claim 2 is characterized in that: Before using the millimeter wave radar to detect the bridge cables, an inclined reflector is set at the corresponding position on the bridge panel.

4. The bridge cable force detection method based on drone and millimeter wave radar as claimed in claim 1 is characterized in that: Also includes: Providing an acceleration sensor, and installing the provided acceleration sensor on the drone; During the flying and stopping process of the UAV, the acceleration sensor is used to detect the vibration of the UAV to obtain vibration data; When processing the detection data, the influence of the vibration data is removed from the detection data, and then the cable force of the bridge cable is calculated.

5. The bridge cable force detection method based on drone and millimeter wave radar as claimed in claim 1 is characterized in that: When the millimeter wave radar is used to detect the bridge cable to be detected, the detection time of the millimeter wave radar is controlled to be 5 minutes.

6. The bridge cable force detection method based on drone and millimeter wave radar as claimed in claim 1 is characterized in that: When adjusting the measurement angle of the millimeter-wave radar, the setting direction of the bridge cable located in the middle is used as a reference, so that the measurement angle of the millimeter-wave radar is perpendicular to the setting direction of the bridge cable located in the middle.

7. The bridge cable force detection method based on drone and millimeter wave radar as claimed in claim 1 is characterized in that: When the millimeter wave radar is used for detection, the measurement range of the millimeter wave radar is made to cover all bridge cables.

8. The bridge cable force detection method based on drone and millimeter wave radar as claimed in claim 1 is characterized in that: The steps of controlling the drone to fly and stop at a position close to the bridge cable to be inspected include: The UAV is controlled to fly and stop below the bridge cables, and the millimeter wave radar is allowed to detect all the bridge cables to be detected at an oblique upward measurement angle.

Images