Suspension arm deflection detection device

Abstract

The utility model discloses a suspension arm deflection detection device, which comprises a fixed plate, and a laser emitter, a stepping motor, a vacuum chuck, a miniature vacuum air pump, a digital steering engine and a development board which are arranged on the fixed plate, the fixed plate is adsorbed and fixed on a suspension arm through the vacuum chuck, the miniature vacuum air pump is used for exhausting air from the vacuum chuck, and the digital steering engine is used for detecting the deflection of the suspension arm. The stepping motor is connected with the digital steering engine and drives the digital steering engine to rotate in a first plane, the digital steering engine is connected with the laser transmitter and drives the laser transmitter to rotate in a second plane, the first plane is perpendicular to the second plane, and the laser transmitter, the stepping motor, the miniature vacuum air pump and the digital steering engine are all connected with the development board. Based on laser phase difference distance measurement and a curve fitting algorithm, the crane jib curve is accurately fitted, the position of each point on the crane jib is obtained and tracked, the change of each point is monitored in real time, the crane jib curve is used for calculating safety parameters such as deflection and the like, the labor intensity of workers is reduced, the detection efficiency is high, the installation is simple and convenient, and the crane jib and other parts are not damaged.

Description

Technical Field

[0001] The utility model belongs to the technical field of engineering machinery measurement, in particular to a boom deflection detection device. Background Art

[0002] Because giant machines such as wheeled cranes work outdoors for a long time and are exposed to the natural environment, the boom will have a certain deflection. The performance of the boom structure will be greatly affected by temperature changes caused by different sunlight intensities and other factors, and even local damage to the structure will occur, such as cracking of the mechanical structure and lateral bending of the crane boom. The boom of the crane will bend, which is not easy to see with the naked eye. Even under overload working conditions, "broken arm" accidents may occur. In order to ensure the normal operation and safe operation of the crane, it is necessary to measure the deflection of the crane boom regularly. At present, the methods for measuring deflection include manual measurement and measurement using machine vision. The existing boom deflection detection technology generally has the disadvantages of being difficult to install and having low accuracy. For example, the commonly used method currently uses the different positions of the laser beam generated by the position sensitive detector to measure the deflection using the distance difference. This method requires two separate components, the position sensitive detector and the measuring device, and is not suitable for long-distance measurement of the boom. For another example, the use of machine vision technology is easily affected by natural ambient light and is not suitable for measurement during outdoor operations. Utility Model Content

[0003] In view of the above problems existing in the prior art, the purpose of the utility model is to provide a boom deflection detection device, which is based on laser phase difference ranging and curve fitting algorithm, accurately fits the boom curve, obtains the position of each point on the boom and tracks it, monitors the change value of each point in real time, and is used to calculate key safety parameters such as deflection. It can be monitored and operated on a mobile terminal, and the safety performance indicators of mechanical parts can be monitored in real time, which greatly reduces the labor intensity of the staff and has high detection efficiency. The detection device is easy to install and does not damage the boom and other parts.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0005] A boom deflection detection device comprises a fixed plate and a laser transmitter mounted on the fixed plate, a stepper motor, a vacuum suction cup, a micro vacuum air pump, a digital servo and a development board, wherein the fixed plate is adsorbed and fixed on the boom by the vacuum suction cup, the micro vacuum air pump is used to evacuate air from the vacuum suction cup, the stepper motor is connected to and drives the digital servo to rotate in a first plane, the digital servo is connected to and drives the laser transmitter to rotate in a second plane, the first plane and the second plane are perpendicular, and the laser transmitter, the stepper motor, the micro vacuum air pump and the digital servo are all connected to the development board.

[0006] As a further improvement of the above technical solution:

[0007] Preferably, the detection device further comprises a vacuum suction cup bracket, one end of the vacuum suction cup bracket is connected to the fixing plate, and the other end is connected to the vacuum suction cup, and the micro vacuum air pump is connected to the vacuum suction cup via an air guide tube.

[0008] Preferably, the vacuum suction cup is made of EPDM rubber foam sponge.

[0009] Preferably, the detection device also includes a temperature and humidity sensor for detecting the temperature and humidity of the environment in which the detection device is located, and the temperature and humidity sensor is connected to the development board.

[0010] Preferably, the detection device further comprises a rotating bracket, one end of which is fixedly connected to the digital servo, and the other end of which is fixedly connected to the laser transmitter.

[0011] Preferably, when the vacuum suction cup is supported on a horizontal ground, the laser transmitter, the digital servo, the stepper motor and the fixing plate are arranged in sequence from top to bottom.

[0012] Preferably, the fixing plate is parallel to the first plane.

[0013] The beneficial effects of the utility model are:

[0014] (1) Based on laser phase difference ranging and curve fitting algorithm, the boom curve is accurately fitted to obtain the position of each point on the boom and track it. The change value of each point is monitored in real time to calculate key safety parameters such as deflection. It can be monitored and operated on mobile terminals and the safety performance indicators of mechanical parts can be monitored in real time, which greatly reduces the labor intensity of staff and improves detection efficiency.

[0015] (2) The detection device can realize position calibration, and the laser transmitter can scan the entire length of the boom to provide comprehensive coverage.

[0016] (3) The detection device is easy to install and does not damage the boom and other parts. The vacuum suction cup is made of EPDM rubber foam sponge, which does not have high requirements on the surface of the boom. The sponge that contacts the entire suction cup with the object can fully contact the uneven surface of the object due to its softness and plasticity. The entire sponge can maintain a good sealing vacuum performance and has a strong suction force. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of an embodiment of the utility model.

[0018] Figure 2 It is a schematic diagram of the bottom structure of an embodiment of the utility model.

[0019] Figure 3 It is a schematic diagram of an embodiment of the utility model in which the detection device is installed on a suspension arm.

[0020] Figure 4 It is a schematic diagram of the detection principle of an embodiment of the utility model. DETAILED DESCRIPTION

[0021] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0022] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0023] A boom deflection detection device, such as Figures 1 to 4 As shown, it includes a laser transmitter 1, a rotating bracket 2, an air guide tube 3, a stepper motor 4, a vacuum suction cup 5, a vacuum suction cup bracket 6, a micro vacuum air pump 7, a digital servo 8, a temperature and humidity sensor 9, a fixing plate 10 and a development board 11.

[0024] The fixing plate 10 is supported by a plurality of vacuum suction cup brackets 6, one end of the vacuum suction cup bracket 6 is connected to the fixing plate 10, and the other end is connected to the vacuum suction cup 5. In this embodiment, four vacuum suction cups 5 and four vacuum suction cup brackets 6 are provided.

[0025] In this embodiment, the vacuum suction cup 5 is made of EPDM foam sponge.

[0026] The micro vacuum air pump 7 is supported and installed on the fixed plate 10. The micro vacuum air pump 7 is connected to the vacuum suction cup 5 through the air guide tube 3. The micro vacuum air pump 7 evacuates the vacuum suction cup 5 through the air guide tube 3, so that the vacuum suction cup 5 is adsorbed on the surface of the object.

[0027] In this embodiment, two micro vacuum air pumps 7 are provided, and every two vacuum suction cups 5 share one micro vacuum air pump 7 .

[0028] In this embodiment, a blind hole is provided in the vacuum suction cup bracket 6, and the vacuum suction cup bracket 6 serves as a bracket and a ventilation duct. Every two vacuum suction cup brackets 6 are connected by a connecting pipe, and the connecting pipe is connected to an air guide tube 3. One end of the vacuum suction cup bracket 6 is connected to the vacuum suction cup 5, and the other end is connected to the connecting pipe, so that the two vacuum suction cups 5 share a micro vacuum air pump 7.

[0029] The stepper motor 4 is mounted on the fixed plate 10, and the digital servo 8 is mounted on the stepper motor 4. The stepper motor 4 is connected to and drives the digital servo 8 to rotate in a plane parallel to the fixed plate 10. The rotation angle of the stepper motor 4 is changed by adjusting the PWM wave output in an electronically controlled manner.

[0030] In this embodiment, the stepper motor 4 is a two-phase four-wire stepper motor.

[0031] One end of the rotating bracket 2 is fixedly connected to the digital servo 8, and the other end is fixedly connected to the laser transmitter 1. The digital servo 8 drives the rotating bracket 2 to rotate in a plane perpendicular to the fixed plate 10, thereby driving the laser transmitter 1 to rotate synchronously.

[0032] In this embodiment, when the vacuum suction cup 5 is supported on a horizontal ground, the laser transmitter 1, the digital steering gear 8, the stepper motor 4, and the fixing plate 10 are arranged in sequence from top to bottom.

[0033] From the above, the stepper motor 4 can drive the digital servo 8 and the laser emitter 1 to rotate synchronously. When the vacuum suction cup 5 is supported on the horizontal ground and the fixed plate 10 is parallel to the horizontal plane, the laser emitter 1 can be driven to rotate in a plane parallel to the horizontal plane and in a plane perpendicular to the horizontal plane under the joint action of the digital servo 8 and the stepper motor 4.

[0034] The development board 11 and the temperature and humidity sensor 9 are arranged on the fixed plate 10. Preferably, the laser emitter 1 is located on the front of the fixed plate 10, and the development board 11 and the temperature and humidity sensor 9 are both arranged on the back of the fixed plate 10. The temperature and humidity sensor 9 is used to detect the temperature and humidity of the environment of the detection device.

[0035] The temperature and humidity sensor 9, the laser transmitter 1, the stepper motor 4, the digital steering gear 8, and the micro vacuum air pump 7 are all electrically connected to the development board 11. The development board 11 has a series of hardware components such as a central processing unit, a memory, an input device, an output device, a data path / bus, and an external resource interface. In this embodiment, the development board 11 adopts a Raspberry Pi development board. The development board 11 can realize a remote radio connection with a control center or a terminal device, thereby realizing remote control and monitoring.

[0036] The development board 11 receives the temperature and humidity data detected by the temperature and humidity sensor 9, the laser emission information of the laser transmitter 1, the rotation information of the stepper motor 4, the rotation information of the digital servo 8, and the information of the micro vacuum air pump 7. The development board 11 can also control the start and stop of the micro vacuum air pump 7, the stepper motor 4, the digital servo 8, and the laser transmitter 1.

[0037] In this embodiment, the laser transmitter 1 is used to measure distance.

[0038] From the above, functionally, the detection device includes a data acquisition module, a position adjustment module, a portable installation and fixing module, and an environmental detection module. Among them, the digital servo 8 and the laser transmitter 1 are used as an angle data collector and a distance data collector respectively; the digital servo 8 and the stepper motor 4 constitute the position adjustment module of the detection device, which can be regarded as a two-panel structure; the micro vacuum air pump 7, the vacuum suction cup 5, and the air guide tube 3 constitute the fixing module of the detection device; the development board 11 and the temperature and humidity sensor 9 constitute the environmental monitoring module of the detection device.

[0039] Based on the above structure, the working principle and use method of the utility model are as follows:

[0040] Step S1: Install the detection device on the boom. Specifically, the air in the vacuum suction cup 5 is extracted by the micro vacuum air pump 7 to achieve negative pressure so that the four vacuum suction cups 5 are adsorbed on the outer wall of the boom, thereby fixing the entire device. Installing the detection device in this way will not cause damage to the original mechanical equipment and does not require modification of the original mechanical equipment.

[0041] Due to factors such as the boom being exposed to sunlight and being frequently pulled down by heavy objects, the boom is mostly bent toward the ground. In order not to block the laser beam from scanning the entire boom and to obtain as much relevant measurement data as possible, the detection device needs to be installed directly below a relatively smooth part of the giant boom. Figure 3 As shown, J is the detection device and B is the boom.

[0042] Step S2: Adjust the initial state of the device. During measurement, the laser beam emitted by the laser transmitter 1 needs to fall on the boom. However, there is a certain error when the detection device is placed manually, that is, there is a certain probability that the emitted laser beam will deviate from the target in the middle part of the boom when the detection device is placed manually, and the measurement may be invalid due to the side bending of the boom. Therefore, it is necessary to verify the normal working state once, that is, to emit a laser beam once. Assume that the distance measured by the laser transmitter 1 is L1, the installation point of the detection device is the starting point, and the number of boom sections extending from the boom is n, and the unit boom length of this model of crane is L0 (in mm). If L1∈(L0*n±500), then the formal deflection measurement can be carried out. Otherwise, it is necessary to start the stepper motor 4 so that the stepper motor 4 drives the digital servo 8 to rotate, and finally the laser emitted by the laser transmitter 1 can hit the boom, so that L1∈(L0*n±500).

[0043] Step S3: Collecting data. In this step, the digital servo 8 is continuously adjusted, that is, the angle value θ is continuously changed, so that the laser beam emitted by the laser transmitter 1 falls on different positions A on the boom along the length direction of the boom, and the distance L measured by the laser transmitter 1 is recorded, such as Figure 4 As shown. The angle value θ is the complementary angle between the laser beam emitted by the laser emitter 1 and the angle between the boom. Until the laser beam completely scans the boom and leaves the measurement range. A discrete point position set is obtained, which is mapped to the rectangular coordinate system as x=Lcosθ, y=Lsinθ.

[0044] Step S3: Data processing. The collected set data is first cleaned and preprocessed using the box plot outlier detection method, and then input into the algorithm program to fit an approximate curve and visualize it. The maximum distance from the line segment connecting the beginning and the end of the curve segment on the fitting curve is calculated, and the position of the point is recorded. The maximum distance value is the deflection value.

[0045] The deflection value during the measurement process can be viewed in real time through the terminal device.

[0046] Furthermore, an alarm program is provided in the development board 11 or on the terminal device, and an alarm may be provided. When the system determines that there is a danger signal, the detection device will alarm, and the terminal platform will also alarm. The alarm program can be specifically set, for example, an alarm will be issued when the temperature or humidity data detected by the temperature and humidity sensor 9 exceeds a set value.

[0047] Finally, it is necessary to explain here that the above embodiments are only used to further illustrate the technical solution of the utility model in detail and cannot be understood as limiting the protection scope of the utility model. Some non-essential improvements and adjustments made by technicians in this field based on the above content of the utility model belong to the protection scope of the utility model.

Claims

1. A boom deflection detection device, characterized in that: The invention comprises a fixing plate (10), a laser transmitter (1) mounted on the fixing plate (10), a stepper motor (4), a vacuum suction cup (5), a micro vacuum air pump (7), a digital steering gear (8) and a development board (11); the fixing plate (10) is adsorbed and fixed on the suspension arm via the vacuum suction cup (5); the micro vacuum air pump (7) is used to evacuate the vacuum suction cup (5); the stepper motor (4) is connected to and drives the digital steering gear (8) to rotate in a first plane; the digital steering gear (8) is connected to and drives the laser transmitter (1) to rotate in a second plane; the first plane and the second plane are perpendicular; the laser transmitter (1), the stepper motor (4), the micro vacuum air pump (7) and the digital steering gear (8) are all connected to the development board (11).

2. The detection device according to claim 1, characterized in that: The detection device also includes a vacuum suction cup bracket (6), one end of the vacuum suction cup bracket (6) is connected to the fixing plate (10), and the other end is connected to the vacuum suction cup (5), and the micro vacuum air pump (7) is connected to the vacuum suction cup (5) via an air guide tube (3).

3. The detection device according to claim 1 or 2, characterized in that: The material of the vacuum suction cup (5) is EPDM foam sponge.

4. The detection device according to claim 1, characterized in that: The detection device also includes a temperature and humidity sensor (9) for detecting the temperature and humidity of the environment in which the detection device is located. The temperature and humidity sensor (9) is connected to the development board (11).

5. The detection device according to claim 1, characterized in that: The detection device also includes a rotating bracket (2), one end of the rotating bracket (2) is fixedly connected to the digital steering gear (8), and the other end of the rotating bracket (2) is fixedly connected to the laser transmitter (1).

6. The detection device according to claim 5, characterized in that: When the vacuum suction cup (5) is supported on a horizontal ground, the laser transmitter (1), the digital steering gear (8), the stepping motor (4), and the fixing plate (10) are arranged in sequence from top to bottom.

7. The detection device according to claim 1, characterized in that: The fixing plate (10) is parallel to the first plane.

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