Shock excitation system and method for testing dynamic characteristics of footbridge

Abstract

The invention discloses an excitation system and method for testing the dynamic characteristics of a footbridge, and the system comprises a plurality of humanoid robots, one of which is provided with a data collection and analysis module; wherein one or more humanoid robots are provided with balancing weights; the control terminal is in communication connection with the humanoid robots and the data acquisition and analysis module and is used for controlling the stride frequency, stride and moving path of the humanoid robots; the monitoring device comprises a plurality of monitoring units, and the monitoring units are distributed on the foot bridge and used for monitoring the vibration acceleration and vibration displacement of the foot bridge; and each monitoring unit is in communication connection with the data acquisition and analysis module. According to the invention, effective excitation of the foot bridge, especially a large-span foot bridge, can be realized, compared with a traditional mode, pedestrian excitation can be simulated more truly, the safety risk caused by adopting pedestrian excitation is avoided, and the test result is accurate and reliable.

Description

Technical Field

[0001] The present invention relates to the field of bridge dynamic characteristics testing, and more particularly to a vibration excitation system and method for testing the dynamic characteristics of a pedestrian bridge. Background Art

[0002] Currently, there are an increasing number of long-span pedestrian bridges spanning highways, railways, and rivers, placing higher demands on the safety and comfort of these bridges, which combine pedestrian passage with scenic features. For example, there are pedestrian landscape suspension bridges with a main span of 369 meters, curved-beam inclined-arch pedestrian bridges with a main arch span of 198 meters, and cable-stayed pedestrian bridges with a main span of 175 meters. These types of pedestrian bridges or pedestrian landscape bridges far exceed the span records and structural forms of traditional beam-type pedestrian bridges. These long-span pedestrian bridges have low natural frequencies and large acceleration responses under pedestrian loads, generally requiring special comfort control research, such as the installation of mass-tuned dampers. Both comfort evaluation and mass-tuned damper design require field measurements to obtain the bridge's true dynamic characteristics, such as acceleration, natural frequency, mode shape, and damping ratio.

[0003] Currently, the excitation methods for obtaining the true dynamic characteristics of pedestrian bridges include: pedestrian excitation, which does not require additional equipment, but the excitation force of a single person is small, and it is difficult to ensure the synchronization of multiple people when cooperating. The frequency and amplitude cannot be accurately controlled, and there are obvious personnel safety hazards; environmental excitation, which is low-cost and does not affect the normal use of the bridge, and is suitable for long-term monitoring, but the excitation force is small, the signal is weak, and it is difficult to control the frequency and amplitude. The data acquisition time is long and the data analysis is complex; artificial excitation, the impact excitation equipment is simple, the excitation force is large, and it is suitable for rapid testing, but it is difficult to simulate the real pedestrian movement effect. The large random error makes it difficult to form the pulse force, and the frequency range is limited due to the inability to control the excitation force and the excitation period. Multi-point synchronous excitation cannot be performed, which cannot meet the requirements for the number and location of measuring points when measuring structural modal vibration shapes, and may also cause local damage to the bridge. Summary of the Invention

[0004] An object of the present invention is to solve at least the above problems and to provide at least the advantages which will be described hereinafter.

[0005] In order to achieve these purposes and other advantages according to the present invention, a vibration excitation system for testing the dynamic characteristics of a pedestrian bridge is provided, comprising: A plurality of humanoid robots, wherein one of the humanoid robots is provided with a data acquisition and analysis module; wherein one or more of the humanoid robots are provided with a counterweight; a control terminal, which is in communication with each of the humanoid robots and the data acquisition and analysis module, and is used to control the step frequency, stride length, and movement path of each of the humanoid robots; The monitoring device includes a plurality of monitoring units, each of which is distributed on the pedestrian bridge and is used to monitor the vibration acceleration and vibration displacement of the pedestrian bridge; each of the monitoring units is communicatively connected to the data acquisition and analysis module.

[0006] Preferably, the monitoring device includes a plurality of displacement monitoring devices and a plurality of acceleration sensors, and the plurality of displacement monitoring devices and the plurality of acceleration sensors are distributed on the bridge deck in a matrix manner.

[0007] Preferably, it further includes an environmental monitoring device arranged on the pedestrian bridge, the environmental monitoring device includes a temperature and humidity sensor and an anemometer, and the temperature and humidity sensor and the anemometer are respectively communicatively connected to the data acquisition and analysis module.

[0008] Another object of the present invention is to provide a vibration excitation method for testing the dynamic characteristics of a pedestrian bridge, using the vibration excitation system for testing the dynamic characteristics of a pedestrian bridge, comprising the following steps: S1. Install the monitoring device on the footbridge, install the data acquisition and analysis module on one of the humanoid robots, and set the counterweight on one or more of the humanoid robots; S2. setting a moving path for each of the humanoid robots on the footbridge; S3, placing each of the humanoid robots at a starting position of its moving path to perform a static bridge test, and obtaining data measured by the monitoring device; S4. Control each of the humanoid robots to move along the movement path set in step S2 through the control terminal, and continuously monitor the vibration of the bridge through the monitoring device.

[0009] Preferably, in step S2, the humanoid robots are set to walk in a queue along the length direction of the footbridge with synchronized amplitude and frequency.

[0010] Preferably, in step S2, the humanoid robots are set to walk in a queue along the width direction of the footbridge with synchronized amplitude and frequency.

[0011] Preferably, in step S2, when setting the initial state, the humanoid robots are randomly distributed on the pedestrian bridge and are set to walk in different directions, synchronous amplitudes, and synchronous frequencies.

[0012] Preferably, in step S2, when setting the initial state, the humanoid robots are randomly distributed on the pedestrian bridge and are set to walk in different directions, with different step amplitudes and different step frequencies.

[0013] Preferably, the method further includes step S5, repositioning each of the humanoid robots to the starting position of the moving path set in step S2, changing the stride and frequency of each of the humanoid robots, and then continuously monitoring the vibration of the bridge through the monitoring device during the movement.

[0014] Preferably, the method further includes step S5, re-positioning each of the humanoid robots at the starting position of the moving path set in step S2, setting each of the humanoid robots to alternately jump and walk while moving along the moving path, and then continuously monitoring the vibration of the bridge through the monitoring device during the movement.

[0015] The present invention has at least the following beneficial effects: 1. The vibration excitation system for testing the dynamic characteristics of pedestrian bridges provided by this invention uses the humanoid structure of a humanoid robot to realistically simulate the vertical excitation force generated by a person walking, as well as the lateral excitation force and torsional excitation effects generated by the alternating movement of the left and right feet. Furthermore, by adjusting the mass of the humanoid robot using a counterweight, it realistically simulates the load of pedestrians of varying weights. This effectively excites pedestrian bridges, especially long-span ones, and avoids the safety risks associated with using pedestrian excitation. The synchronization of multiple humanoid robots in a group far exceeds that of multiple people working together, resulting in higher excitation efficiency and more accurate test results. This provides accurate and reliable technical support for the decision-making of vibration reduction measures, the design of vibration control dampers, and the high-precision evaluation of pedestrian bridge comfort.

[0016] 2. The vibration excitation method for testing the dynamic characteristics of a pedestrian bridge provided by the present invention can simulate various states when actually walking across the pedestrian bridge, giving full play to the characteristics and advantages of humanoid robots, making the vibration excitation and dynamic performance parameter testing of the pedestrian bridge safe, accurate and efficient, improving the accuracy of the parameter design values and layout positions of the subsequent vibration suppression dampers, comprehensively improving the vibration excitation efficiency of the dynamic characteristics test, reducing the cost of project implementation, and having good environmental adaptability.

[0017] Other advantages, objectives and features of the present invention will be reflected in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a side structural diagram of the vibration excitation system for testing the dynamic characteristics of a pedestrian bridge according to the present invention; Figure 2 for Figure 1 Schematic diagram of the AA cross-section structure; DETAILED DESCRIPTION

[0019] The present invention will be described in further detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0020] It should be noted that the experimental methods described in the following embodiments are conventional methods unless otherwise specified, and the reagents and materials are commercially available unless otherwise specified; in the description of the present invention, the terms "horizontal", "longitudinal", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships 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, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0021] like Figure 1 and Figure 2 As shown, the present invention provides a vibration excitation system for testing the dynamic characteristics of a pedestrian bridge, comprising: A plurality of humanoid robots 4, wherein one of the humanoid robots 4 is provided with a data acquisition and analysis module 3; wherein one or more of the humanoid robots 4 is provided with a counterweight; a control terminal, which is in communication with each of the humanoid robots 4 and the data acquisition and analysis module 3 and is used to control the step frequency, stride length and movement path of each of the humanoid robots 4; The monitoring device 2 includes a plurality of monitoring units, each of which is distributed on the footbridge 1 and is used to monitor the vibration acceleration and vibration displacement of the footbridge 1 ; each of the monitoring units is communicatively connected to the data acquisition and analysis module 3 .

[0022] In this technical solution, the humanoid structure of the humanoid robot 4 can realistically simulate the vertical excitation force generated by a person walking, as well as the lateral excitation force and torsional excitation effect generated by the alternating movement of the left and right feet. Furthermore, the mass of the humanoid robot 4 is adjusted by the counterweight block to realistically simulate the load of pedestrians of different weights. This effectively excites pedestrian bridges, especially long-span ones, avoiding the safety risks of using pedestrian excitation. Furthermore, the control terminal can achieve precise control of each humanoid robot. The synchronization of multiple humanoid robots in a group far exceeds that of multiple people working together, resulting in more accurate test results. The humanoid robot 4 can be a commercially available humanoid robot with high-precision motion control capabilities, a programmable gait, adjustable cadence and stride length, a deadweight of 20-100 kg, a cadence range of 0.5-5 Hz, and a maximum jumping height of 20 cm. The control terminal is a host computer with a built-in control system for the humanoid robots 4. It displays the gait parameters and real-time position of each humanoid robot 4 via a display device and adjusts the gait parameters and movement path of each humanoid robot 4 via the control terminal. Wireless communication is implemented between the control terminal and each humanoid robot 4 and the data acquisition and analysis module 3, as well as between the data acquisition and analysis module 3 and each monitoring unit. The data acquisition and analysis module 3 converts the collected analog signals into digital signals and transmits them to the control terminal for storage and display. The control terminal performs time-domain and frequency-domain analysis on the monitored vibration acceleration and displacement, calculating the root mean square acceleration, peak acceleration, and phase difference of acceleration at each measuring point to assess vibration intensity. It also identifies the natural frequency, damping ratio, and modal shape of the pedestrian bridge, providing accurate and reliable technical support for decision-making on vibration reduction measures, designing vibration control dampers, and accurately evaluating the comfort of pedestrian bridges.

[0023] In another technical solution, the monitoring device 2 includes multiple displacement monitoring devices and multiple acceleration sensors, which are distributed in a matrix on the bridge deck. The acceleration sensors are preferably piezoelectric acceleration sensors with excellent high-frequency response, outputting analog signals, which are then digitized by the ADC module of the data acquisition and analysis module 3. The vibration displacement can be obtained by quadratic integration of the acceleration data monitored by the acceleration sensor. The displacement monitoring device collects vibration data at a preset sampling rate. The displacement monitoring device can use the structural static and dynamic vertical displacement synchronous measurement device disclosed in the invention patent application number CN202411349335.4 and the inertial bridge lateral dynamic deflection measurement device disclosed in the invention patent application number CN202411349080.1 to monitor the lateral and vertical vibration displacement of the bridge. The acceleration data is calculated by performing a quadratic differential on the monitored displacement data. In addition, by comparing the data of the displacement monitoring device with the data monitored by the acceleration sensor, cross-validation is performed to correct errors and ensure the consistency of the test results.

[0024] In another technical solution, an environmental monitoring device is also included on the pedestrian bridge 1, and the environmental monitoring device includes a temperature and humidity sensor and an anemometer, and the temperature and humidity sensor and the anemometer are respectively connected to the data acquisition and analysis module 3. By collecting temperature, humidity and wind speed, comprehensive analysis is performed to eliminate the interference of environmental factors. The present invention also provides a vibration excitation method for testing the dynamic characteristics of a pedestrian bridge, using the vibration excitation system for testing the dynamic characteristics of a pedestrian bridge, comprising the following steps: S1, installing the monitoring device 2 on the footbridge 1, installing the data acquisition and analysis module 3 on one of the humanoid robots 4, and setting the counterweight on one or more of the humanoid robots 4; The monitoring device 2 is installed at the mid-span, quarter-span, third-quarter-span, and corresponding locations on the piers / supports of the pedestrian bridge 1. Simultaneously, the data acquisition and analysis module 3 is installed on one of the humanoid robots 4 outside the bridge. The data acquisition and analysis module 3 is then activated and put into operation, and wireless communication between the monitoring device 2 and the data acquisition and analysis module 3 is debugged.

[0025] S2, setting a moving path of each of the humanoid robots 4 on the footbridge 1; To simulate the stimulation generated by a real person walking, the following movement paths can be set in step S2: Path 1: The humanoid robots 4 walk in a queue along the length of the footbridge 1 with synchronized amplitude and frequency; Path 2: The humanoid robots 4 walk in a queue along the width direction of the footbridge 1 with synchronized amplitude and frequency; Path three: in an initial state, the humanoid robots 4 are randomly distributed on the footbridge 1 and are set to walk in different directions, synchronous amplitudes, and synchronous frequencies; Path 4: In the initial state, the humanoid robots 4 are randomly distributed on the footbridge 1 and are set to walk in different directions, with different step amplitudes and different step frequencies; The queue-like walking in Path 1 and Path 2 refers to arranging multiple rows of the humanoid robots 4 along the walking direction, with each row including a plurality of the humanoid robots 4 .

[0026] S3. Place each of the humanoid robots 4 at the starting position of its moving path to perform a static test on the bridge and obtain the data measured by the monitoring device; through the static test, record the baseline vibration of the pedestrian bridge 1 under the current natural environment excitation to eliminate the influence of environmental noise.

[0027] S4. Control each of the humanoid robots 4 to move along the path set in step S2 through the control terminal, while continuously monitoring through the monitoring device 2. In actual testing, step S4 may be repeated multiple times to obtain sufficient monitoring data.

[0028] Furthermore, the process further includes step S5, where each humanoid robot 4 is repositioned at the starting position of the movement path set in step S2, and the stride length and cadence of each humanoid robot 4 are adjusted. The humanoid robots 4 are then continuously monitored by the monitoring device 2 during their walking. For paths one and two, the stride length and cadence of each humanoid robot 4 are adjusted by the same amount; for paths three and four, the stride length and cadence of some of the humanoid robots may be randomly adjusted.

[0029] In order to simulate the jumping behavior that may occur when pedestrians walk, in step S5, each of the humanoid robots 4 is placed back at the starting position of the moving path set in step S2, and each of the humanoid robots 4 is set to alternately jump and walk while moving along the moving path, and then continuously monitored by the monitoring device 2 during the movement.

[0030] Through the vibration excitation method for testing the dynamic characteristics of the pedestrian bridge, various states of actual walking through the pedestrian bridge 1 can be simulated, and the characteristics and advantages of the humanoid robot 4 can be fully utilized, so that the vibration excitation and dynamic performance parameter testing of the pedestrian bridge are safe, accurate and efficient, and the monitoring data obtained are accurate and reliable, which improves the accuracy of the subsequent damper parameter design values and layout positions for vibration suppression, comprehensively improves the excitation efficiency of the dynamic characteristics test, reduces the project implementation cost, and has good environmental adaptability.

[0031] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A vibration excitation system for testing the dynamic characteristics of a pedestrian bridge, characterized in that: include: A plurality of humanoid robots, wherein one of the humanoid robots is provided with a data acquisition and analysis module; wherein one or more of the humanoid robots are provided with a counterweight; a control terminal, which is in communication with each of the humanoid robots and the data acquisition and analysis module, and is used to control the step frequency, stride length, and movement path of each of the humanoid robots; The monitoring device includes a plurality of monitoring units, each of which is distributed on the pedestrian bridge and is used to monitor the vibration acceleration and vibration displacement of the pedestrian bridge; each of the monitoring units is communicatively connected to the data acquisition and analysis module.

2. The vibration excitation system for testing the dynamic characteristics of a footbridge according to claim 1, characterized in that: The monitoring device includes a plurality of displacement monitoring devices and a plurality of acceleration sensors, and the plurality of displacement monitoring devices and the plurality of acceleration sensors are distributed on the bridge deck in a matrix manner.

3. The vibration excitation system for testing the dynamic characteristics of a pedestrian bridge according to claim 1, characterized in that: It also includes an environmental monitoring device arranged on the pedestrian bridge, and the environmental monitoring device includes a temperature and humidity sensor and an anemometer. The temperature and humidity sensor and the anemometer are respectively connected to the data acquisition and analysis module for communication.

4. A vibration excitation method for testing the dynamic characteristics of a pedestrian bridge, using the vibration excitation system for testing the dynamic characteristics of a pedestrian bridge according to claim 1, characterized in that: The following steps are involved: S1. Install the monitoring device on the footbridge, install the data acquisition and analysis module on one of the humanoid robots, and set the counterweight on one or more of the humanoid robots; S2. setting a moving path for each of the humanoid robots on the footbridge; S3, placing each of the humanoid robots at a starting position of its moving path to perform a static bridge test, and obtaining data measured by the monitoring device; S4. Control each of the humanoid robots to move along the movement path set in step S2 through the control terminal, and continuously monitor the vibration of the bridge through the monitoring device.

5. The vibration excitation method for testing the dynamic characteristics of a footbridge according to claim 4, characterized in that: In step S2, the humanoid robots are set to walk in a queue along the length direction of the footbridge with synchronized amplitude and frequency.

6. The vibration excitation method for testing the dynamic characteristics of a footbridge according to claim 4, wherein: In step S2, the humanoid robots are set to walk in a queue along the width direction of the footbridge with synchronized amplitude and frequency.

7. The vibration excitation method for testing the dynamic characteristics of a pedestrian bridge according to claim 4, wherein: In step S2, the humanoid robots are randomly distributed on the footbridge in an initial state and are set to walk in different directions, synchronous amplitudes, and synchronous frequencies.

8. The vibration excitation method for testing the dynamic characteristics of a pedestrian bridge according to claim 4, wherein: In step S2, the humanoid robots are randomly distributed on the pedestrian bridge in an initial state and are set to walk in different directions, with different step amplitudes and different step frequencies.

9. The vibration excitation method for testing the dynamic characteristics of a footbridge according to any one of claims 5 to 8, characterized in that: The method further includes step S5, re-placing each of the humanoid robots at the starting position of the moving path set in step S2, changing the stride and frequency of each of the humanoid robots, and then continuously monitoring the vibration of the bridge through the monitoring device during the movement.

10. The vibration excitation method for testing the dynamic characteristics of a footbridge according to any one of claims 5 to 8, wherein: The method also includes step S5, re-placing each of the humanoid robots at the starting position of the moving path set in step S2, setting each of the humanoid robots to alternately jump and walk while moving along the moving path, and then continuously monitoring the vibration of the bridge through the monitoring device during the movement.

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