A lever-type excitation system and excitation method

Abstract

This invention discloses a lever-type vibration excitation system and method, including an excitation component, a detection component, and a control system. The excitation component includes a first base, a servo actuator, a first lever, a second lever, a mass block, and a second base. The first base is fixedly mounted on the top of the bridge deck, with its top end rotatably connected to one end of the first and second levers. Mass blocks are fixedly attached to the other ends of both the first and second levers. Second bases are fixedly installed on the bridge deck on both sides of the first base, with their tops fixedly connected to the fixed ends of the servo actuators. The output ends of the servo actuators on both sides are hinged to the first and second levers, respectively. The detection component is located on the excitation component and the main bridge structure. The control system is connected to the servo actuator and the detection component. This invention uses the extension and retraction of the servo actuator to drive the first and second levers to rotate around the first base, causing the mass block to move periodically. By leveraging the lever principle, the excitation force is amplified, achieving efficient and precise vibration of the bridge.

Description

Technical Field

[0001] This invention belongs to the field of bridge inspection technology, and more specifically, relates to a lever-type vibration excitation system and vibration excitation method. Background Technology

[0002] In the field of bridge engineering, dynamic characteristic testing of bridge structures (covering core aspects such as modal analysis and seismic performance assessment) is a key technical means to ensure the safe operation of bridges throughout their entire life cycle. As the core execution equipment for dynamic characteristic testing, the excitation system's performance parameters, such as excitation frequency, amplitude control accuracy, dynamic response speed, and diversity of excitation modes, directly determine the accuracy and reliability of the test data, thus affecting the conclusions drawn from the assessment of the bridge structure's dynamic characteristics.

[0003] Currently, the commonly used vibration excitation technologies in the field of bridge engineering mainly include three types: direct excitation, eccentric wheel excitation, and conventional servo actuator excitation. However, all of these solutions have significant drawbacks in practical engineering applications and are difficult to meet the high-precision dynamic characteristic testing requirements of long-span bridges and complex irregular-shaped bridges.

[0004] For both direct excitation and eccentric wheel excitation schemes, the excitation force is generated by the reciprocating or rotational motion of the mechanical structure. Due to the limitations of mechanical transmission characteristics, the range of excitation frequency adjustment is narrow, and they are usually only suitable for low-frequency excitation scenarios. They cannot output the high-frequency, stable sinusoidal excitation signal required for testing long-span bridges and complex bridge structures. At the same time, it is difficult to achieve precise control of the excitation amplitude and waveform of such schemes, resulting in poor consistency of excitation output. In addition, additional vibration interference is easily generated during mechanical transmission, leading to a low signal-to-noise ratio of the collected test data, which seriously affects the accuracy of the analysis results of the dynamic characteristics of the bridge structure.

[0005] For conventional servo actuator excitation solutions, large-stroke servo actuators are required to achieve large-amplitude excitation. However, large-stroke actuators have inherent drawbacks such as large size and high weight, which not only increases the difficulty of installation and transportation in space-constrained scenarios such as bridge decks, but also increases the manufacturing cost and operating energy consumption of the equipment. More importantly, the dynamic response speed of large-stroke actuators is slow, making it difficult to maintain stable output performance under high-frequency excitation conditions, and thus failing to meet the dual technical requirements of "large amplitude" and "high response speed".

[0006] In addition, most existing vibration systems have a relatively simple vibration mode, usually only able to achieve one of vertical or torsional vibration. When it is necessary to simultaneously complete the dynamic characteristic test of the bridge in both vertical and torsional directions, different types of vibration equipment need to be replaced. This not only leads to cumbersome operation procedures and a significant extension of the test cycle, but also causes inconsistencies in test benchmarks due to repeated disassembly and assembly, reducing the reliability of comparative analysis of test data in different directions. Summary of the Invention

[0007] To address the aforementioned deficiencies or improvement needs of existing technologies, this invention provides a lever-type vibration excitation system and method. Through precise coordinated control of the movement directions of the servo actuators on both sides by the main control module, rapid switching between vertical and torsional vibration modes can be achieved. During vertical vibration, the main control module outputs synchronous, same-direction commands to drive the actuators to extend and retract synchronously, causing the lever to rise and fall synchronously to achieve concentrated vertical vibration. During torsional vibration, a synchronous, reverse command is used, causing the lever to move in the opposite direction to generate a torsional torque. No equipment components need to be replaced, significantly reducing disassembly, assembly, and debugging costs and testing cycles. Furthermore, both modes share the same installation and testing benchmark, effectively avoiding benchmark offset errors and ensuring the uniformity and reliability of test data, providing precise support for the comprehensive dynamic characteristic analysis of bridges. The system optimizes the lever fulcrum position and overall structural parameters, relying on the lever amplification principle to achieve efficient displacement amplification, amplifying the servo actuators'... The system transforms small-stroke displacement into large-stroke motion of the mass block, overcoming the technical bottleneck that "large-amplitude excitation requires large-stroke actuators." This allows the system to use conventional small-stroke servo actuators, reducing the procurement cost of core components, shrinking the overall system size and weight, lowering on-site installation space requirements, reducing installation time, and improving adaptability and convenience in complex bridge testing environments. Utilizing a full-link closed-loop control system, the system achieves dynamic and precise control of the excitation process. The data acquisition and processing module collects the excitation system's operating parameters and the bridge's vibration response parameters in real time, processes them, and feeds them back to the main control module. The main control module, combined with comparative analysis of preset target parameters, generates correction commands in real time to adjust the actuator output parameters, effectively offsetting interference from lever transmission clearance, mass block inertial force, and environmental vibration. This fully meets the requirements of high-precision dynamic characteristic testing of bridges for excitation stability and accuracy.

[0008] To achieve the above objectives, according to one aspect of the present invention, a lever-type vibration excitation system is provided, comprising an excitation component, a detection component, and a control system; wherein... The vibration excitation assembly includes a first base, a servo actuator, a first lever, a second lever, a mass block, and a second base. The first base is fixedly mounted on the top of the bridge deck, and its top end is rotatably connected to one end of the first lever and the second lever. The other end of the first lever and the second lever are both fixedly connected to a mass block. The second base is fixedly installed on the bridge deck on both sides of the first base. The top of the second base is fixedly connected to the fixed end of the servo actuator. The output ends of the two servo actuators are respectively hinged to the first lever and the second lever. The extension and retraction of the servo actuator drives the first lever and the second lever to rotate around the top end of the first base, thereby causing the mass block to form a periodic motion. The vibration force is amplified by lever principle, thereby improving excitation efficiency. The detection component is installed on the excitation component and the main structure of the bridge, and is used to collect the vibration parameters of the excitation component and the bridge in real time. The control system is connected to the servo actuator and the detection component. It receives vibration parameters fed back by the detection component and outputs control commands to the servo actuator according to the preset control strategy, driving the mass block to move up and down reciprocally, thereby applying an efficient and precise excitation force to the bridge.

[0009] Furthermore, the fixed ends of the servo actuators on both sides of the first base are hinged to both sides of the first base via hinge seats.

[0010] Furthermore, by adjusting the placement of the excitation components, bridge dynamic characteristic tests in different directions can be achieved. When a vertical excitation test is required on the bridge, the excitation components are placed and positioned along the longitudinal direction of the bridge. When a torsional vibration test is required on a bridge, the vibration excitation assembly is arranged and positioned along the transverse direction of the bridge.

[0011] Furthermore, in the vertical excitation mode, the servo actuators on both sides move synchronously, thereby driving the first lever and the second lever to move synchronously upward or downward, so that the mass blocks on both sides move synchronously and in the same direction with the corresponding first lever and the second lever, so as to apply a concentrated vertical excitation force to the bridge deck.

[0012] Furthermore, in the torsional excitation mode, the two servo actuators extend and retract with the same motion frequency and opposite motion directions. One servo actuator pushes the first lever upward, while the other servo actuator pulls the second lever downward, thereby causing the mass blocks on both sides to reciprocate synchronously in opposite directions with the first and second levers. The opposite motion of the mass blocks on both sides forms a torsional torque around the center of the bridge surface.

[0013] Furthermore, the detection component includes an accelerometer and a displacement sensor. The accelerometer is respectively deployed at preset test positions on the mass block and the bridge deck to collect the motion acceleration parameters of the mass block and the vibration acceleration parameters of the bridge deck in real time. The displacement sensor includes a contact-type wire displacement sensor, whose fixed end is fixed to the bridge deck and whose movable end is hinged to the mass block. It is used to accurately measure the real-time relative displacement parameters of the mass block relative to the bridge deck. Each sensor is electrically connected to the control system to transmit the collected parameter signals to the control system for data processing in real time.

[0014] Furthermore, the excitation component amplifies displacement based on the lever amplification principle, and the displacement amplification relationship is defined by the following formula: ; In the formula: L1 is the length of the lever power arm, specifically the straight-line distance from the top hinge point of the first base to the hinge point of the servo actuator; L2 is the length of the lever resistance arm, specifically the straight-line distance from the top hinge point of the first base to the connection point of the mass block; k is the displacement amplification factor of the lever; S1 is the output stroke of the servo actuator; S2 is the output displacement of the mass block after being amplified by the lever.

[0015] According to a second aspect of the present invention, a lever-type excitation method is provided, implemented using the aforementioned lever-type excitation system, comprising the following steps: S100: Assemble and deploy the excitation and detection components to the bridge inspection area, complete the hinge and fixation of each component, and establish the electrical connection between the detection components and the control system. S200: By inputting preset parameters through the control system, and sending motion commands to the servo actuators on both sides through the control system, the servo actuators are driven to perform extension and retraction movements, which drive the first lever and the second lever to move, and drive the mass block to perform up and down reciprocating movements by means of the lever amplification principle. S300: The detection component collects the operating parameters of the excitation component and the vibration response parameters of the bridge in real time, and transmits the collected raw signals to the data acquisition and processing module of the control system. After processing, the data is fed back to the main control module. S400: The control system compares the feedback data with the preset target parameters. If they are inconsistent, the control system controls the output parameters of the servo actuator to ensure that the excitation force stably matches the test requirements and completes the bridge dynamic characteristic test.

[0016] Furthermore, if it is necessary to conduct vertical dynamic characteristic tests on the bridge, the excitation components are arranged and positioned along the longitudinal direction of the bridge. According to the bridge test requirements, the frequency and output stroke of the servo actuators are input, and the main control module of the control system outputs synchronous and unidirectional motion control commands to the servo actuators on both sides, driving the servo actuators on both sides to perform precise synchronous extension and retraction movements, thereby driving the first lever and the second lever to move synchronously upward or downward, so that the mass blocks on both sides perform synchronous and unidirectional reciprocating movements with the corresponding first lever and the second lever, so as to apply a concentrated vertical excitation force to the bridge deck.

[0017] Furthermore, if it is necessary to conduct torsional dynamic characteristic tests on the bridge, the excitation assembly is arranged and positioned along the transverse direction of the bridge. According to the bridge test requirements, the frequency and output stroke of the servo actuator are input, and the main control module of the control system outputs synchronous reverse motion control commands to the servo actuators on both sides, driving the servo actuators on both sides to extend and retract with the same motion frequency and opposite motion directions. One servo actuator pushes the first lever upward, and the other servo actuator pulls the second lever downward, thereby causing the mass blocks on both sides to reciprocate synchronously in the opposite direction with the first lever and the second lever. The reverse motion of the mass blocks on both sides forms a torsional torque around the center of the bridge deck, applying a uniform and continuous torsional excitation to the bridge deck.

[0018] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects: 1. The lever-type vibration excitation system of the present invention achieves precise coordinated control of the movement direction of the servo actuators on both sides through the main control module. When it is necessary to change the excitation direction, only the arrangement direction of the excitation components needs to be changed. When vertical vibration test is required, the main control module outputs synchronous same-direction movement command to drive the servo actuators on both sides to extend and retract synchronously, and drive the first lever and the second lever to rise and fall synchronously, so as to realize the vertical concentrated vibration of the mass block on the bridge deck. When torsional vibration test is required, the main control module switches to synchronous reverse movement command, controls the servo actuators on both sides to move at the same frequency and in opposite directions, and drives the first lever and the second lever to move in opposite directions, forming a torsional torque around the center of the bridge deck. No equipment components need to be replaced, which can significantly reduce the time cost of equipment disassembly, assembly and debugging, and significantly shorten the overall test cycle. At the same time, the two excitation modes share the same base 1 installation benchmark and the detection component layout benchmark, which effectively avoids the system error caused by benchmark offset under different test modes, ensures the benchmark uniformity of vertical and torsional test data, and thus improves the reliability of comparison between the two types of data, providing more accurate data support for the comprehensive dynamic characteristics analysis of bridges.

[0019] 2. The lever-type vibration excitation system of the present invention, through the fulcrum positions (i.e., the hinge points on the upper part of the base) of the first and second levers and the overall structural parameters of the levers, based on the lever amplification principle, amplifies the small-stroke displacement output of the servo actuator into a large-displacement motion of the mass block, realizing "small-stroke actuator output of large-amplitude vibration". It eliminates the need for expensive and bulky large-stroke servo actuators, and only conventional small-stroke servo actuators are needed to meet the requirements of large-amplitude testing. This not only significantly reduces the procurement cost of actuators, but also significantly reduces the overall size and weight of the system. At the same time, the compact structural design reduces the space requirements for on-site installation, reduces installation time, and further improves the ease of installation of the system in the complex testing environment of bridges.

[0020] 3. The lever-type vibration excitation system of the present invention achieves dynamic and precise control of the excitation process by constructing a full-link closed-loop control system of "main control module - servo actuator - data acquisition and processing module". The data acquisition and processing module collects the operating parameters of the excitation system and the vibration response parameters of the bridge in real time, and feeds back the collected raw signals to the main control module in real time after processing. The main control module compares and analyzes the feedback data in conjunction with the preset test target parameters, generates correction commands in real time, and dynamically adjusts the output parameters of the servo actuator, effectively avoiding deviations caused by lever transmission clearance, mass block inertial force, and environmental vibration. Through this closed-loop control mechanism, it can ensure that the mass block always outputs a stable sinusoidal vibration waveform, and the system has a wide excitation frequency adjustment range and the amplitude control accuracy error is controlled within a very small range, which can fully meet the requirements of high-precision dynamic characteristic testing of bridges for excitation stability and accuracy.

[0021] 4. The lever-type vibration excitation system of the present invention is convenient to implement, highly adaptable, and applicable to a wide range of scenarios. Its structural design follows the principles of lightweight and compactness, with each component adopting a modular design for easy transportation, loading and unloading, and on-site assembly. The entire system can be disassembled into a base, a first lever, a second lever, a servo actuator, a mass block, a control system, and detection components. This saves storage space during transportation. On-site installation only requires hinged and fixed connections, electrical connections, and simple debugging of each module before it can be put into use. Dismantling is equally simple, significantly reducing the labor intensity and time cost of on-site construction. The system has strong environmental adaptability; a base of suitable specifications can be selected according to the width of different bridge decks. By adjusting the lever arm ratio of the first and second levers, it can match the different vibration amplitude requirements of different bridges, making it suitable for dynamic characteristic testing scenarios of various types of bridges. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a lever-type excitation system according to an embodiment of the present invention; Figure 2 This is a schematic diagram of vertical excitation of a lever-type excitation system according to an embodiment of the present invention; Figure 3 This is a schematic diagram of torsional excitation of a lever-type excitation system according to an embodiment of the present invention; Figure 4 This is a schematic diagram of a lever-type excitation system according to Embodiment 2 of the present invention; Figure 5 This is a schematic diagram of the vertical excitation of a lever-type excitation system according to Embodiment 2 of the present invention; Figure 6 This is a schematic diagram of torsional excitation of a lever-type excitation system according to Embodiment 2 of the present invention; Figure 7 This is a schematic flowchart of a lever-type excitation method according to an embodiment of the present invention.

[0023] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically: 1-first base, 2-servo actuator, 3-first lever, 4-second lever, 5-mass block, 6-second base. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0025] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0026] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0027] In this patent, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0028] Example 1 like Figure 1-3As shown, this embodiment of the invention provides a lever-type vibration excitation system, including an excitation component, a detection component, and a control system. The excitation component includes a first base 1, a servo actuator 2, a first lever 3, a second lever 4, a mass block 5, and a second base 6. The first base 1 is fixedly mounted on the top of the bridge deck, with its top end rotatably connected to one end of the first lever 3 and the second lever 4. Mass blocks 5 are fixedly connected to the other ends of both the first lever 3 and the second lever 4. Second bases 6 are fixedly installed on the bridge deck on both sides of the first base 1. The top of the second base 6 is fixedly connected to the fixed end of the servo actuator 2. The output ends of the two servo actuators 2 are hinged to the first lever 3 and the second lever 4, respectively. The system operates via a servo actuator... The extension and retraction of actuator 2 drives the first lever 3 and the second lever 4 to rotate around the top of the first base 1, thereby causing the mass block 5 to form a periodic motion. This leverage principle amplifies the excitation force and improves excitation efficiency. The detection component is installed on the excitation component and the main bridge structure to collect vibration parameters of the bridge in real time. The control system is connected to the servo actuator 2 and the detection component. It receives the vibration parameters fed back by the detection component and, according to a preset control strategy, outputs control commands to the servo actuator 2 to drive the mass block 5 to reciprocate up and down, thus applying a highly efficient and precise excitation force to the bridge and ensuring the accuracy and reliability of bridge vibration testing. The excitation system of this invention, through the coordinated operation of the lever structure and servo drive, can achieve flexible adjustment and precise control of the excitation force, providing efficient and precise excitation of the bridge and ensuring that the excitation parameters are precisely matched with the bridge's dynamic characteristic testing requirements. Compared with traditional excitation devices, it has the advantages of compact structure, high excitation efficiency, and excellent control precision, and is suitable for dynamic characteristic testing of various bridge structures.

[0029] Furthermore, by adjusting the orientation of the excitation components, bridge dynamic characteristic tests in different directions can be achieved. When a vertical excitation test is required, the excitation components are positioned along the longitudinal direction of the bridge; when a torsional excitation test is required, the excitation components are positioned along the transverse direction of the bridge, so that the direction of the excitation force or torsional moment is precisely matched with the test target, ensuring the effectiveness and reliability of different types of excitation tests.

[0030] Furthermore, the control system is electrically connected to the servo actuator 2 and the detection component, and includes a main control module and a data acquisition and processing module. The main control module is used to output precise control commands to regulate the movement direction of the servo actuator 2, thereby achieving precise driving of the excitation operation. The data acquisition and processing module is used to receive test data collected by the detection component in real time, and to filter, convert, and analyze the data to provide high-precision data support for the command optimization of the main control module, ensuring the timeliness and accuracy of closed-loop control, thereby improving the control accuracy of the excitation system and the reliability of the test data.

[0031] Furthermore, in the vertical excitation mode, the control system outputs synchronous and unidirectional motion control commands to the servo actuators 2 on both sides, driving the servo actuators 2 to precisely and synchronously extend and retract, thereby driving the first lever 3 and the second lever 4 to move synchronously upward or downward, so that the mass blocks 5 on both sides reciprocate synchronously and in the same direction with the corresponding first lever 3 and second lever 4, so as to apply a concentrated vertical excitation force to the bridge deck. Through this coordinated control method, the direction of action of the vertical excitation force is concentrated and the amplitude is stable, effectively improving the consistency of the bridge's vertical vibration response and the reliability of the test data, and ensuring the accuracy of the bridge's vertical dynamic characteristic test.

[0032] Furthermore, in the torsional excitation mode, the control system outputs synchronous reverse motion control commands to the two servo actuators 2, driving the two servo actuators 2 to extend and retract with the same motion frequency and opposite motion directions. One servo actuator 2 pushes the first lever 3 upward, while the other servo actuator 2 pulls the second lever 4 downward, thereby causing the two mass blocks to reciprocate synchronously in the opposite direction with the first lever 3 and the second lever 4. The reverse motion of the two mass blocks 5 generates a torsional torque around the center of the bridge deck, applying a uniform and continuous torsional excitation to the bridge deck, ensuring the symmetry and stability of the torsional vibration response, and effectively improving the data accuracy and reliability of the bridge torsional dynamic characteristics test.

[0033] Furthermore, the detection component includes an accelerometer and a displacement sensor. The accelerometer is respectively deployed at the mass block 5 and the preset test position on the bridge deck to collect the motion acceleration parameters of the mass block 5 and the vibration acceleration parameters of the bridge deck in real time. The displacement sensor includes a contact-type wire displacement sensor, whose fixed end is fixed to the bridge deck and whose movable end is hinged to the mass block 5. It is used to accurately measure the real-time relative displacement parameters of the mass block 5 relative to the bridge deck. Each sensor is electrically connected to the control system to transmit the collected parameter signals to the control system for data processing in real time.

[0034] Furthermore, the excitation component amplifies displacement based on the lever amplification principle, and the displacement amplification relationship is defined by the following formula: ; In the formula: L1 is the length of the lever power arm, specifically the straight-line distance from the top hinge point of the first base 1 to the hinge point of the servo actuator 2; L2 is the length of the lever resistance arm, specifically the straight-line distance from the top hinge point of the first base 1 to the connection point of the mass block 5; k is the displacement amplification factor of the lever; S1 is the output stroke of servo actuator 2; S2 is the output displacement of mass block 5 after being amplified by the lever.

[0035] Specifically, the lever arm ratio of the first lever 3 and the second lever 4 can be adjusted according to the bridge tonnage and test amplitude requirements to match the different requirements of different bridges for excitation amplitude, making it suitable for dynamic characteristic testing scenarios of various types of bridges.

[0036] Furthermore, the total mass of the mass block 5 is precisely set according to the target excitation force requirement, and its center of mass always coincides with the motion trajectory of the lever end during the reciprocating motion, so as to avoid additional interference torque caused by the displacement of the center of mass; the sinusoidal displacement, maximum acceleration, peak excitation force and torsional excitation torque of the mass block 5 are calculated by the following formulas.

[0037] The sinusoidal displacement of the mass block is: ; The maximum acceleration is: ; The peak excitation force is: ; The torsional excitation torque is: ; In the formula: m is the total mass of the two mass blocks 5; f is the excitation frequency of servo actuator 2; The center-to-center distance between the two mass blocks 5 on both sides of D.

[0038] Example 2 like Figure 4-6 As shown, this embodiment of the invention provides another lever-type vibration system. In this embodiment, all other contents are the same as those in Embodiment 1, the only difference being that the fixed ends of the servo actuators 2 on both sides of the first base 1 are hinged to both sides of the first base 1 via hinge seats.

[0039] Example 3 Combination Figure 1-6 ,like Figure 7 As shown, this invention provides a lever-type excitation method, implemented using the aforementioned lever-type excitation system, with the following specific steps: S100: Assemble and deploy the excitation and detection components to the bridge inspection area, complete the hinge and fixation of each component, and establish the electrical connection between the detection components and the control system. S200: Input preset parameters through the control system and send motion commands to the servo actuators 2 on both sides through the control system to drive the servo actuators 2 to extend and retract, drive the first lever 3 and the second lever 4 to move, and drive the mass block 5 to move up and down by means of the lever amplification principle. S300: The detection component collects the operating parameters of the excitation component and the vibration response parameters of the bridge in real time, and transmits the collected raw signals to the data acquisition and processing module of the control system. After processing, the data is fed back to the main control module. S400: The control system compares the feedback data with the preset target parameters. If they are inconsistent, the control system controls the output parameters of the servo actuator 2 to ensure that the excitation force stably matches the test requirements and completes the bridge dynamic characteristic test.

[0040] Furthermore, if a vertical dynamic characteristic test of the bridge is required, the excitation assembly is positioned along the longitudinal direction of the bridge. Based on the bridge testing requirements, the frequency f and output stroke S2 ​​of the servo actuator 2 are input. The main control module of the control system outputs synchronous and unidirectional motion control commands to the servo actuators 2 on both sides, driving them to precisely and synchronously extend and retract. This, in turn, drives the first lever 3 and the second lever 4 to move synchronously upwards or downwards, causing the mass blocks 5 on both sides to reciprocate synchronously and in the same direction with the corresponding first lever 3 and second lever 4, thus applying a concentrated vertical excitation force to the bridge deck. The direction of the excitation force changes periodically with the sinusoidal motion of the mass blocks, ultimately forming a stable vertical sinusoidal excitation. To ensure the stability of the vibration, i.e., to avoid deviations caused by lever transmission gaps, mass block inertia, and environmental vibrations, the control system collects data from the detection assembly in real time and compares the collected data with a preset target. If the data is inconsistent with the target parameters, the control system controls the output parameters of the servo actuator 2 to achieve the vertical dynamic characteristic test of the bridge.

[0041] Furthermore, if a torsional dynamic characteristic test of the bridge is required, the excitation assembly is positioned along the transverse direction of the bridge. Based on the bridge testing requirements, the frequency f and output stroke S2 ​​of the servo actuator 2 are input. The main control module of the control system outputs synchronous reverse motion control commands to the servo actuators 2 on both sides, driving them to precisely extend and retract at the same frequency and in opposite directions. One servo actuator 2 pushes the first lever 3 upwards, while the other servo actuator 2 pulls the second lever 4 downwards, thereby causing the mass blocks on both sides to move in the same direction as the first lever 3 and the second lever 4. The reciprocating motion of the two mass blocks 5 in opposite directions generates a torsional torque around the center of the bridge deck, applying a uniform and continuous torsional excitation to the bridge deck. The direction of the torsional torque changes periodically with the sinusoidal motion of the mass blocks 5, eventually forming a stable torsional sinusoidal excitation. To ensure the stability of the vibration, i.e. to avoid deviations caused by lever transmission clearance, mass block inertial force, and environmental vibration, the control system collects data from the detection components in real time and compares the collected data with the preset target. If the data is inconsistent with the target parameters, the control system controls the output parameters of the servo actuator 2 to realize the test of the torsional dynamic characteristics of the bridge.

[0042] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A lever-type excitation system, characterized in that, Includes vibration excitation components, detection components, and a control system; among which, The excitation assembly includes a first base (1), a servo actuator (2), a first lever (3), a second lever (4), a mass block (5), and a second base (6). The first base (1) is fixedly mounted on the top of the bridge deck, and its top end is rotatably connected to one end of the first lever (3) and the second lever (4). The other ends of the first lever (3) and the second lever (4) are both fixedly connected to the mass block (5). The second base (6) is fixedly installed on the bridge deck on both sides of the first base (1). The top of the second base (6) is fixedly connected to the fixed end of the servo actuator (2). The output ends of the two servo actuators (2) are respectively hinged to the first lever (3) and the second lever (4). The first lever (3) and the second lever (4) are driven to rotate around the top end of the first base (1) by the extension and retraction action of the servo actuator (2), thereby driving the mass block (5) to form a periodic motion. The excitation force is amplified by lever principle, and the excitation efficiency is improved. The detection component is installed on the excitation component and the main structure of the bridge, and is used to collect the vibration parameters of the excitation component and the bridge in real time. The control system is connected to the servo actuator (2) and the detection component. It receives the vibration parameters fed back by the detection component and outputs control commands to the servo actuator (2) according to the preset control strategy, driving the mass block (5) to move up and down reciprocally, thereby applying an efficient and precise excitation force to the bridge.

2. The lever-type excitation system according to claim 1, characterized in that, The fixed ends of the servo actuators (2) on both sides of the first base (1) are hinged to both sides of the first base (1) through hinge seats.

3. The lever-type excitation system according to claim 1, characterized in that, By adjusting the placement of the excitation components, bridge dynamic characteristics tests can be performed in different directions. When a vertical excitation test is required on a bridge, the excitation components are placed and positioned along the longitudinal direction of the bridge. When a torsional vibration test is required on a bridge, the vibration excitation assembly is arranged and positioned along the transverse direction of the bridge.

4. A lever-type excitation system according to any one of claims 1-3, characterized in that, In the vertical excitation mode, the two servo actuators (2) move synchronously, thereby driving the first lever (3) and the second lever (4) to move synchronously upward or downward, so that the mass blocks (5) on both sides move synchronously and in the same direction with the corresponding first lever (3) and second lever (4) to apply a concentrated vertical excitation force to the bridge deck.

5. A lever-type excitation system according to any one of claims 1-3, characterized in that, In the torsional excitation mode, the two servo actuators (2) extend and retract with the same motion frequency and opposite motion direction. One servo actuator (2) pushes the first lever (3) to move upward, and the other servo actuator (2) pulls the second lever (4) to move downward, thereby causing the two mass blocks (5) to move synchronously and in opposite directions with the first lever (3) and the second lever (4). The opposite motion of the two mass blocks (5) forms a torsional torque around the center of the bridge surface.

6. The lever-type excitation system according to claim 1, characterized in that, The detection component includes an acceleration sensor and a displacement sensor. The acceleration sensor is respectively placed at the mass block (5) and the bridge deck at the preset test position, and is used to collect the motion acceleration parameters of the mass block (5) and the vibration acceleration parameters of the bridge deck in real time. The displacement sensor includes a contact-type wire displacement sensor, whose fixed end is fixed to the bridge deck and whose movable end is hinged to the mass block (5). It is used to accurately measure the real-time relative displacement parameters of the mass block (5) relative to the bridge deck. Each sensor is electrically connected to the control system and transmits the collected parameter signals to the control system in real time for data processing.

7. A lever-type excitation system according to any one of claims 1-3, characterized in that, The excitation component amplifies displacement based on the lever amplification principle, and its displacement amplification relationship is defined by the following formula: ； In the formula: L1 is the length of the lever power arm, specifically the straight-line distance from the top hinge point of the first base (1) to the hinge point of the servo actuator (2); L2 is the length of the lever resistance arm, specifically the straight-line distance from the top hinge point of the first base (1) to the connection point of the mass block (5); k is the displacement amplification factor of the lever; S1 is the output stroke of the servo actuator (2); S2 is the output displacement of the mass block (5) after being amplified by the lever.

8. A lever-type excitation method, characterized in that, For implementation of a lever-type excitation system as described in any one of claims 1-7, characterized in that it includes the following steps: S100: Assemble and deploy the excitation and detection components to the bridge inspection area, complete the hinge and fixation of each component, and establish the electrical connection between the detection components and the control system. S200: Input preset parameters through the control system and send motion commands to the servo actuators (2) on both sides through the control system to drive the servo actuators (2) to perform extension and retraction actions, drive the first lever (3) and the second lever (4) to move, and drive the mass block (5) to perform up and down reciprocating motion by means of lever amplification principle; S300: The detection component collects the operating parameters of the excitation component and the vibration response parameters of the bridge in real time, and transmits the collected raw signals to the data acquisition and processing module of the control system. After processing, the data is fed back to the main control module. S400: The control system compares the feedback data with the preset target parameters. If they are inconsistent with the target parameters, the control system controls the output parameters of the servo actuator (2) to ensure that the excitation force is stably matched to the test requirements and completes the bridge dynamic characteristic test.

9. The lever-type excitation method according to claim 8, characterized in that, If it is necessary to conduct a vertical dynamic characteristic test of the bridge, the excitation component is arranged and positioned along the longitudinal direction of the bridge. According to the bridge test requirements, the frequency and output stroke of the servo actuator (2) are input. The main control module of the control system outputs synchronous and unidirectional motion control commands to the servo actuators (2) on both sides, driving the servo actuators (2) on both sides to perform precise synchronous extension and retraction movements, thereby driving the first lever (3) and the second lever (4) to move synchronously upward or downward, so that the mass blocks (5) on both sides perform synchronous and unidirectional reciprocating movements with the corresponding first lever (3) and second lever (4), so as to apply a concentrated vertical excitation force to the bridge deck.

10. A lever-type excitation method according to claim 8, characterized in that, If a torsional dynamic characteristic test of a bridge is required, the excitation assembly is arranged and positioned along the transverse direction of the bridge. The frequency and output stroke of the servo actuator (2) are input according to the bridge test requirements. The main control module of the control system outputs synchronous reverse motion control commands to the two servo actuators (2) to drive the two servo actuators (2) to extend and retract with the same motion frequency and opposite motion direction. One servo actuator (2) pushes the first lever (3) to move upward, and the other servo actuator (2) pulls the second lever (4) to move downward. This causes the mass blocks on both sides to move synchronously and in the opposite direction with the first lever (3) and the second lever (4). The reverse motion of the mass blocks (5) on both sides forms a torsional torque around the center of the bridge surface, which applies a uniform and continuous torsional excitation to the bridge surface.

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