Elastic cantilever beam active vibration reduction demonstration device based on closed-loop control
By designing an active vibration damping demonstration device for elastic cantilever beams based on closed-loop control, using DC motors and strain gauge to measure vibration signals, the active vibration damping effect with a simple structure and low cost is achieved, and the existing device has complex structure and high cost is solved, and it is suitable for teaching demonstration and principle verification.
Patent Information
- Application Number
- CN202422183352.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-06
- Publication Date
- 2025-06-06
- Estimated Expiration
- 2034-09-06
AI Technical Summary
The existing active vibration damping devices are complex in structure and expensive, and are not suitable for teaching demonstration and principle research, resulting in a lack of intuitive and easy-to-operate active vibration damping principle demonstration devices in the fields of education and research.
An active vibration-absorbing demonstration device for elastic cantilever beams based on closed-loop control is designed, and vibration suppression is achieved through the closed-loop control principle.
It realizes active vibration damping effect with simple structure, low cost and easy to operate. It is suitable for teaching demonstration and principle verification, with concise principles and intuitive effects.
Smart Images
Figure CN222952789U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of active vibration reduction, in particular to an elastic cantilever beam active vibration reduction demonstration device based on closed-loop control. Background Art
[0002] In the fields of construction, transportation, aerospace, etc., engineering machinery and equipment often face the problem of excessive vibration during operation, which has a negative impact on their work quality and efficiency. The vibration reduction methods for dealing with vibration hazards in engineering can be divided into two categories: passive vibration reduction and active vibration reduction. The traditional passive vibration reduction method achieves vibration reduction by adding springs and damping elements. Although it has the advantages of simple structure and easy application, the vibration reduction effect is limited and it is difficult to adapt to the diverse vibration reduction needs. In contrast, active vibration reduction technology uses modules such as sensors, controllers and actuators to accelerate the attenuation of vibration by inputting energy into the system, which can more effectively suppress vibration. However, the existing active vibration reduction devices are often complex in structure and expensive, and are not suitable for teaching demonstrations and principle research. In the field of education and research, there is currently a lack of intuitive and easy-to-operate active vibration reduction principle demonstration devices, which makes it difficult for students and researchers to intuitively understand the working principle and effect of active vibration reduction technology. Utility Model Content
[0003] The purpose of the utility model is to provide an elastic cantilever beam active vibration reduction demonstration device based on closed-loop control which has a simple structure, low cost and is easy to operate. The device actuates a DC motor according to the closed-loop control principle to achieve vibration suppression of a single-degree-of-freedom elastic cantilever beam. The device has a simple design and intuitive effects and is suitable for teaching demonstrations and principle verification.
[0004] The single-degree-of-freedom active vibration reduction demonstration device based on closed-loop control provided by the utility model comprises: an elastic cantilever beam, a clamping fixture, a closed-loop control switch, a counterweight, a DC motor, a strain gauge, a strain amplification module, a motor driver, a mounting base, and a fixed base; wherein:
[0005] The clamping fixture, closed-loop control switch and mounting base are arranged on a fixed base;
[0006] One end of the elastic cantilever beam is fixed on the clamping fixture, and the balancer is located on the other end of the elastic cantilever beam;
[0007] The DC motor is fixed on the counterweight;
[0008] The strain gauges are adhered to the surfaces of both sides of the elastic cantilever beam;
[0009] The strain amplification module and the motor driver are placed on the mounting base plate;
[0010] The strain gauge is connected to the strain amplification module, and the strain amplification module is connected to the motor driver; the DC motor is connected to the motor driver through a closed-loop control switch;
[0011] The strain amplification module includes a signal amplification function and a zero point calibration function;
[0012] The motor driver realizes the regulation of the speed and direction of the DC motor by inputting a differential analog signal.
[0013] In the utility model, the strain gauge is connected in a full-bridge circuit to ensure that the measurement of the bending strain of the elastic cantilever beam has sufficient accuracy. The total number of strain gauges is 4, which are symmetrically pasted on the two side surfaces of one end of the elastic cantilever beam close to the clamping tooling, and the two strain gauges on one side are arranged up and down (that is, symmetrically distributed along the width direction of the elastic cantilever beam and the two side surfaces).
[0014] In the utility model, the counterweight is two counterweight blocks with an L-shaped top cross-section, which are symmetrically arranged on both sides of the elastic cantilever beam to clamp and fix the elastic cantilever beam; the two counterweight blocks are symmetrically arranged to form a semi-enclosed square inner cavity, and the DC motor is arranged in the inner cavity and clamped and fixed by the two counterweight blocks.
[0015] In the utility model, the strain amplification module and the motor driver share an external DC power supply.
[0016] When the utility model is used, the counterweight is moved, and the elastic cantilever beam drives the counterweight at the end and the DC motor to have a slowly decaying free vibration (left-right vibration); during the free vibration of the elastic cantilever beam, the strain amplification module measures the voltage signal of the Wheatstone bridge composed of strain gauges in real time, thereby completing the measurement of the vibration signal of the elastic cantilever beam, and outputs a differential analog signal after zero point calibration and signal amplification. The greater the vibration, the stronger the measured voltage signal, and the stronger the converted differential analog signal; during the free vibration of the elastic cantilever beam, the motor driver converts the differential analog signal output by the strain amplification module into a corresponding motor drive current, and outputs it to the DC motor through a closed-loop control switch; during the free vibration of the elastic cantilever beam, the closed-loop control switch is pressed, the DC motor is connected to the motor driver, and the DC motor adjusts the speed according to the size of the converted motor drive current, thereby generating reaction torques of different sizes on the elastic cantilever beam at different vibration amplitudes, and the free vibration of the elastic cantilever beam is effectively suppressed.
[0017] The utility model adopts an elastic cantilever beam and a counterweight as vibration reduction objects, and utilizes a DC motor to actuate and suppress the free vibration of the elastic cantilever beam. The whole device has a simple structure, low cost, and is easy to assemble and operate. The demonstration device adopts a resistance strain measurement method to collect the vibration signal of the vibration reduction object, and actuates the DC motor based on the closed-loop control principle to generate a reaction torque to achieve vibration suppression. The principle is simple and the effect is intuitive, and the utility model is suitable for teaching demonstrations and principle verification related to active vibration reduction. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 It is a structural schematic diagram of the elastic cantilever beam active vibration reduction demonstration device based on closed-loop control described in the utility model.
[0019] Figure 2 The utility model is a schematic diagram of the assembly of the elastic cantilever beam, the clamping fixture, the counterweight and the DC motor of the elastic cantilever beam active vibration reduction demonstration device based on closed-loop control.
[0020] Figure 3 It is a circuit diagram of the elastic cantilever beam active vibration reduction demonstration device based on closed-loop control described in the utility model.
[0021] Figure 4 This is a strain gauge bridge circuit diagram of the elastic cantilever beam active vibration reduction demonstration device based on closed-loop control described in the utility model.
[0022] The numbers in the figure are: 1 is an elastic cantilever beam, 2 is a clamping fixture, 3 is a closed-loop control switch, 4 is a counterweight, 5 is a DC motor, 6 is a strain gauge, 7 is a strain amplification module, 8 is a motor driver, 9 is a mounting base, and 10 is a fixed base. DETAILED DESCRIPTION
[0023] The utility model comprises an elastic cantilever beam 1, a clamping tool 2, a closed-loop control switch 3, a counterweight 4, a DC motor 5, a strain gauge 6, a strain amplification module 7, a motor driver 8, a mounting base 9 and a fixed base 10; wherein:
[0024] The clamping fixture 2, the closed-loop control switch 3 and the mounting base 9 are placed on the fixed base 10; one end of the elastic cantilever beam 1 is fixed on the clamping fixture 2, and the counterweight 4 is placed on the other end of the elastic cantilever beam 1; the DC motor 5 is fixed on the counterweight 4; the strain gauge 6 is pasted on the two side surfaces of the elastic cantilever beam 1; the strain amplification module 7 and the motor driver 8 are placed on the mounting base 9; Figure 1 shown.
[0025] The elastic cantilever beam 1 is cut from spring steel sheets, and there is no special restriction on its shape. Preferably, the two ends of the elastic cantilever beam 1 are rectangular structures that match the clamping fixture 2 and the counterweight 4, with through holes dug for fixing and assembly, and the middle deformation section is an elongated rectangle with through holes dug for threading or fixing wires. There is no special restriction on the size of the elastic cantilever beam 1. Preferably, the middle deformation section of the elastic cantilever beam 1 is 200-400 mm long, 20-30 mm wide, and 0.3-1.0 mm thick. More preferably, the middle deformation section of the elastic cantilever beam 1 is 250 mm long, 20 mm wide, and 0.5 mm thick.
[0026] The clamping fixture 2 is composed of a steel L-shaped bracket and a steel pressing block. The L-shaped bracket and the pressing block are provided with through holes for clamping the elastic cantilever beam 1. Other conventional clamps of different types may also be used.
[0027] The counterweight 4 is two metal counterweight blocks with an L-shaped top cross section, which are symmetrically arranged on both sides of the elastic cantilever beam 1, clamping and fixing the elastic cantilever beam 1; the two counterweight blocks are symmetrically arranged to form a semi-enclosed square inner cavity, and the DC motor 5 is arranged in the inner cavity and clamped and fixed by the two metal blocks; the counterweight blocks are respectively provided with threaded holes and through holes for fixing with the elastic cantilever beam 1 and the DC motor 5; Figure 2 shown.
[0028] The type of the closed-loop control switch 3 is not limited. Preferably, the closed-loop control switch 3 is a self-resetting button switch.
[0029] The strain gauge 6 is connected in a full-bridge circuit to ensure that the bending strain of the elastic cantilever beam 1 is measured with sufficient accuracy. The total number of strain gauges is 4, which are symmetrically attached to the surfaces of both sides of one end of the elastic cantilever beam close to the clamping fixture, and the two strain gauges on one side are arranged up and down (i.e., symmetrically distributed along the width direction of the elastic cantilever beam and the surfaces of both sides); the full-bridge circuit is a conventional setting in the art, and the connection method can refer to the following. Figure 4 shown.
[0030] The strain amplification module 7 includes a signal amplification function and a zero point calibration function, and the specific model is not limited. Preferably, the strain amplification module 7 adopts the MV-20B of Kemei Intelligent Control. The working voltage of the strain amplification module 7 is not limited. Preferably, the working voltage of the strain amplification module 7 is 9-30 V. More preferably, the working voltage of the strain amplification module 7 is 9V.
[0031] The motor driver 8 controls the speed and direction of the DC motor 5 by inputting a differential analog signal, and the specific model is not limited. Preferably, the motor driver 8 adopts the AQMD_NS series motor driver of Acecon. More preferably, the motor driver 8 adopts AQMD2410NS-B3. The working voltage of the motor driver 8 is not limited. Preferably, the working voltage of the motor driver 8 is 9-24 V. More preferably, the working voltage of the motor driver 8 is 9 V.
[0032] The material and size of the mounting base plate 9 are not limited. Preferably, the mounting base plate 9 is made of an acrylic plate or an aluminum alloy plate, with a length of 200-300 mm, a width of 60-90 mm, and a thickness of 5-15 mm. More preferably, the mounting base plate 9 is made of an acrylic plate, with a length of 250 mm, a width of 75 mm, and a thickness of 9 mm. In some embodiments, the mounting base plate 9 is provided with a through hole, and the strain amplification module 7 and the motor driver 8 are connected to the mounting base plate 9 by screws.
[0033] The material and size of the fixed base 10 are not limited. Preferably, the fixed base 10 is made of a steel or aluminum flat plate with a length of 250-500 mm, a width of 150-250 mm, and a thickness of 9-15 mm. More preferably, the fixed base 10 is made of a steel flat plate with a length of 300 mm, a width of 200 mm, and a thickness of 13 mm. In some embodiments, the fixed base 10 is provided with a threaded hole, and the clamping fixture 2, the closed-loop control switch 3, and the mounting base 9 are connected to the fixed base 10 by screws.
[0034] In some embodiments, the fixed base 10 can be fixed in the aluminum alloy box shell by screws, so that the demonstration device is easy to carry and place.
[0035] The full-bridge circuit composed of the strain gauges 6 is connected to the strain amplification module 7. The strain amplification module 7 converts the millivolt voltage signal generated by the full-bridge circuit composed of the strain gauges 6 into a differential analog signal within the range of -3.3 ~ +3.3 V after zero point adjustment and signal amplification, and outputs the signal.
[0036] The strain amplification module 7 is connected to the motor driver 8. The motor driver 8 converts the differential analog signal output by the strain amplification module 7 into a corresponding motor driving current and outputs it.
[0037] The DC motor 5 is connected to the motor driver 8 via the closed-loop control switch 3 .
[0038] The strain amplification module 7 and the motor driver 8 share a 9 V external DC power supply.
[0039] When doing a teaching demonstration, the operator first moves the counterweight, and the elastic cantilever beam drives the counterweight at the end and the DC motor to have a slowly decaying free vibration (left and right vibration); during the free vibration of the elastic cantilever beam, the strain amplification module measures the voltage signal of the Wheatstone bridge composed of strain gauges in real time, thereby completing the measurement of the vibration signal of the elastic cantilever beam, and outputs a differential analog signal after zero point calibration and signal amplification. The greater the vibration, the stronger the measured voltage signal, and the stronger the converted differential analog signal; during the free vibration of the elastic cantilever beam, the motor driver converts the differential analog signal output by the strain amplification module into a corresponding motor drive current, and outputs it to the DC motor through a closed-loop control switch; during the free vibration of the elastic cantilever beam, the closed-loop control switch is pressed, the DC motor is connected to the motor driver, and the DC motor adjusts the speed according to the size of the converted motor drive current, thereby generating different sizes of reaction torques on the elastic cantilever beam at different vibration amplitudes, and the free vibration of the elastic cantilever beam is effectively suppressed.
[0040] The beneficial effects of the utility model are that the active vibration reduction demonstration device of the utility model adopts an elastic cantilever beam and a counterweight block as vibration reduction objects, and utilizes a DC motor to actuate and suppress the free vibration of the elastic cantilever beam. The whole device has a simple structure, low cost, and is easy to assemble and operate. The demonstration device adopts a resistance strain measurement method to collect the vibration signal of the vibration reduction object, and actuates the DC motor based on the closed-loop control principle to generate a reaction torque to achieve vibration suppression. The principle is simple and the effect is intuitive, and the utility model is suitable for teaching demonstrations and principle verification related to active vibration reduction.
[0041] Although the above methods are illustrated and described as a series of structures for simplicity of explanation, it should be understood and appreciated that these methods are not specifically limited because according to one or more embodiments, some structures may occur in different orders and / or concurrently with other actions from those illustrated and described herein or not illustrated and described herein but understandable to those skilled in the art.
[0042] The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein, but should be granted the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. An elastic cantilever beam active vibration reduction demonstration device based on closed-loop control, characterized in that: include: Elastic cantilever beam, clamping fixture, closed-loop control switch, counterweight, DC motor, strain gauge, strain amplification module, motor driver, mounting base, fixed base; Among them: The clamping fixture, closed-loop control switch and mounting base are arranged on a fixed base; One end of the elastic cantilever beam is fixed on the clamping fixture, and the balancer is located on the other end of the elastic cantilever beam; The DC motor is fixed on the counterweight; The strain gauges are adhered to the surfaces of both sides of the elastic cantilever beam; The strain amplification module and the motor driver are placed on the mounting base plate; The strain gauge is connected to the strain amplification module, and the strain amplification module is connected to the motor driver; the DC motor is connected to the motor driver through a closed-loop control switch; The strain amplification module includes a signal amplification function and a zero point calibration function; The motor driver realizes the regulation of the speed and direction of the DC motor by inputting a differential analog signal.
2. The elastic cantilever beam active vibration reduction demonstration device according to claim 1 is characterized in that: The strain gauges are connected in a full-bridge circuit to ensure sufficient accuracy in measuring the bending strain of the elastic cantilever beam. The total number of strain gauges is 4, which are symmetrically pasted on the surfaces of both sides of one end of the elastic cantilever beam close to the clamping tooling, and the two strain gauges on one side are arranged up and down.
3. The elastic cantilever beam active vibration reduction demonstration device according to claim 2 is characterized in that: The counterweights are two counterweight blocks with an L-shaped top cross-section, which are symmetrically arranged on both sides of the elastic cantilever beam, clamping and fixing the elastic cantilever beam; the two counterweight blocks are symmetrically arranged to form a semi-enclosed square inner cavity, and the DC motor is arranged in the inner cavity and clamped and fixed by the two counterweight blocks.
4. The elastic cantilever beam active vibration reduction demonstration device according to claim 1, characterized in that: The strain amplification module and the motor driver share an external direct current power supply.