An improved wet end processing device for pipeline sonar

Abstract

The present invention relates to the technical field of underwater acoustic signal detection, and particularly to an improved wet end processing device for pipeline sonar, which mainly consists of five parts: a transducer, a conductive slip ring and a stepping motor, a receiving preprocessing circuit, a processing circuit and a transmitting circuit; the processing circuit is successively connected to the receiving preprocessing circuit, the conductive slip ring and the stepping motor, and the transducer, the processing circuit is successively connected to the transmitting circuit and the conductive slip ring and the stepping motor, and the processing circuit delivers the processed data to a display and control device through an Ethernet interface. The present invention can be used for multi-channel parallel operation of pipeline sonar in the underwater acoustic field, and compared with traditional pipeline sonar, can improve the processing efficiency of pipeline sonar and the pipeline detection efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of underwater acoustic signal detection, and particularly relates to an improved wet end processing device for pipeline sonar. Background Art

[0002] 1. Basic situation of traditional technology:

[0003] The traditional plugging - pumping - dredging - detection method is time - consuming and laborious, and there are safety hazards for personnel to go down the well. There is an urgent need to adopt advanced technical means for replacement. The diameters of rain - sewage pipelines are mostly between 400 mm and 1200 mm. The internal environments of rainwater pipes and sewage pipes are slightly different. The water quality in rainwater pipes is relatively clear but there are many suspended solids, and the floating objects are relatively single, such as branches and leaves. The water in sewage pipes is mostly black and stinky, with diverse floating objects: plastic products, steel wool balls, and other domestic garbage, with a strong smell and harmful gases such as hydrogen sulfide. It is necessary to detect structural defects in the pipeline, such as rupture, deformation, offset, undulation, disconnection, hidden connection of branch pipes, siltation, and foreign object insertion.

[0004] Under the full - water condition, optical devices such as cameras are severely restricted. The best detection method is to use sonar for detection. Existing sonar detection technologies usually use single - beam mechanical ring - scanning sonar (pipeline sonar), which can only scan the cross - section of the pipeline, has a slow scanning rate, and can only detect deformation, siltation, and hidden connection of branch pipes. Other defects (such as cracks) are difficult or extremely difficult to identify because of too low resolution and difficult actual operation. In addition, the detection efficiency of single - beam sonar is low (mechanical rotation scanning, and the image needs to be reconstructed).

[0005] Disadvantages of traditional technology:

[0006] Traditional pipeline sonar has the following disadvantages:

[0007] (1) Low measurement efficiency and long time consumption: Traditional pipeline sonar is mainly single - beam mechanical ring - scanning sonar. Its working principle is mainly to control a single - channel transducer to rotate one circle through the rotation of a motor built in the device to collect signals for one week of the pipe network. This working method is restricted by the sonar echo transmission time and processing time. As a result, the motor cannot rotate too fast, and the operation speed of the underwater robot for pipe network detection cannot be too fast, otherwise, the phenomenon of lost frames in the pipe network detection image will occur.

[0008] (2) Low resolution: Limited by the sonar working frequency, the working center frequency of traditional pipeline sonar is not greater than 2.5 MHz, and its horizontal and vertical opening - angle resolutions are also above 1.5°.

[0009] The main technical problems to be solved by the present invention are as follows:

[0010] (1) Improve the detection efficiency of pipeline sonar and accelerate the inspection efficiency of pipeline sonar for urban pipe networks.

[0011] (2)Improve the resolution of pipeline sonar. Summary of the Invention

[0012] Aiming at the deficiencies of the prior art, the present invention discloses an improved wet-end processing device for pipeline sonar and its structure. The present invention can be used for multi-channel parallel operation of pipeline sonar in the underwater acoustic field. Compared with traditional pipeline sonar, it can improve the processing efficiency of pipeline sonar and the pipeline detection efficiency.

[0013] The present invention is realized through the following technical solutions:

[0014] An improved wet-end processing device for pipeline sonar mainly consists of a transducer, a conductive slip ring, a stepping motor, a receiving preprocessing circuit, a processing circuit and a transmitting circuit; the processing circuit is successively connected to the receiving preprocessing circuit, the conductive slip ring and the stepping motor, and the transducer, the processing circuit is successively connected to the transmitting circuit and the conductive slip ring and the stepping motor, and the processing circuit delivers the processed data to the display and control device through an Ethernet interface.

[0015] Preferably, the cross-section of the housing of the transducer is arranged in a regular hexagon structure, and six transducer probes are evenly distributed on the circumferential surface of the housing of the transducer. The transducer probes are driven by the stepping motor to rotate more than 60 circles within 1 minute.

[0016] Preferably, the function of the conductive slip ring is to transmit electrical signals, and at the same time, its connection part can also conduct electricity during relative rotation, and the wires will not be wound. The stator end of the conductive slip ring is connected to the stepping motor to form a fixed part, and the rotor end drives the transducer provided with six transducer probes.

[0017] Preferably, the conductive slip ring is customized and designed with seven coils.

[0018] Preferably, the stepping motor has large torque and low temperature rise, adopts numerical control winding, has high consistency, and adopts a circular design in structural design.

[0019] Preferably, the receiving preprocessing circuit mainly consists of the following three parts:

[0020] Fixed amplification circuit, select the AD8222 dual-channel, high-performance instrumentation amplifier to achieve pre-stage impedance matching and fixed-gain amplification, the gain is set to 10-20 dB, and the AD8222 adopts a small 4 mm×4 mm LFCSP package;

[0021] Voltage-controlled amplification circuit, select the 8-channel, ultra-low-power variable-gain amplifier VCA8500 chip with a low-noise preamplifier from TI Company;

[0022] For the local oscillator circuit, the dedicated DDS chip AD9834 of Analog Devices, Inc. is selected to generate the local oscillator frequency.

[0023] Preferably, the VCA8500 chip integrates a fixed preamplifier circuit, a programmable attenuation circuit, and a programmable gain amplifier circuit to achieve a dynamic gain control of 46 dB.

[0024] Preferably, when the local oscillator circuit operates, it configures through a single-chip microcomputer to generate a fixed frequency of 6 MHz for mixing with the signal at the receiving end, and then the I-channel signal and Q-channel signal at the low-frequency end are achieved through a low-pass filter. Subsequently, data acquisition is realized through the built-in ADC of the single-chip microcomputer. The mixer selects the NE602 type mixer of Signetics Corporation, and the cut-off frequency of the low-pass filter is set to 200 kHz. A low-pass filter is built through an operational amplifier to achieve signal low-pass filtering.

[0025] Preferably, the processing circuit uses FPGA and MCU as the control cores. The FPGA selects the XC7A100TCSG model FPGA chip of the Artix7 series of Xilinx Corporation, and the MCU selects the STM32F407 model single-chip microcomputer of STMicroelectronics.

[0026] Preferably, the transmitting circuit consists of the following three parts:

[0027] The transmitting excitation signal generation circuit is used to generate the required working frequency, working pulse width, and working bandwidth.

[0028] The power amplification circuit is used to convert the transmitting excitation signal from a digital PWM signal into an analog signal and then realize power amplification to convert it into a high-voltage signal.

[0029] The matching circuit is used to match the capacitive reactance and inductive reactance between the transmitting circuit and the transducer to ensure that the transmitted waveform is not distorted.

[0030] The present invention has the following beneficial effects:

[0031] (1) In the wet end design of the improved pipeline sonar, 6 sub-transducers are evenly distributed at equal angles on the circular surface. Under the condition that other conditions remain unchanged, the detection efficiency can be theoretically increased by 6 times.

[0032] (2) Optimize the circuit design of the wet end processing system of the improved pipeline sonar, increase the sonar working frequency to 6 MHz, and achieve a horizontal and vertical opening angle resolution of 0.8° for the improved pipeline sonar, doubling the resolution compared with the traditional pipeline sonar. Description of the Drawings

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0034] Figure 1 This is the overall functional block diagram of the pipeline sonar of the present invention.

[0035] Figure 2 This is the working schematic diagram of the conductive slip ring of the present invention.

[0036] Figure 3 This is the wiring schematic diagram of the conductive slip ring of the present invention; where (a) is a side sectional view, (b) is a side view, and (c) is a front sectional view.

[0037] Figure 4 This is the internal structure block diagram of the AD8222 chip of the present invention.

[0038] Figure 5 This is the internal structure block diagram of the VCA8500 chip of the present invention.

[0039] Figure 6 This is the functional block diagram of the processing circuit of the present invention.

[0040] Figure 7 This is the functional block diagram of the transmitting circuit of the present invention.

[0041] In the figure: 1 - transducer, 2 - conductive slip ring and stepper motor, 3 - receiving preprocessing circuit, 4 - processing circuit, 5 - transmitting circuit. Detailed implementation manners

[0042] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0043] Such as Figures 1-7As shown in the figure, the embodiment of the present invention provides a technical solution for an improved wet end processing device of a pipeline sonar, which mainly consists of five parts: a transducer 1, a conductive slip ring and a stepper motor 2, a receiving preprocessing circuit 3, a processing circuit 4 and a transmitting circuit 5; the processing circuit 4 is successively connected to the receiving preprocessing circuit 3, the conductive slip ring and the stepper motor 2, and the transducer 1, and the processing circuit 4 is successively connected to the transmitting circuit 5 and the conductive slip ring and the stepper motor 2. The processing circuit 4 delivers the processed data to the display and control device through an Ethernet interface.

[0044] The cross-section of the housing of the transducer 1 is arranged in a regular hexagon structure. Six transducer probes are evenly distributed on the circumferential surface of the housing of the transducer 1. The transducer probes are driven by a stepper motor to rotate more than 60 circles within 1 minute. Specifically: the housing of the pipeline sonar transducer works at normal underwater temperature. A sealing ring and sealant are added between the metal and non-metal housings, and the internal and external power supplies and signals of the instrument are connected by a sealed joint. The transducer 1 consists of six probes, which are evenly distributed in a regular hexagon. The probes are driven by a stepper motor to rotate and can rotate more than 60 circles within 1 minute. The whole instrument is filled with light paraffin oil for heat dissipation.

[0045] As Figure 2 shown, the function of the conductive slip ring is to transmit electrical signals. At the same time, electricity can be transmitted when its connection part rotates relatively, and the wires will not be wound. The stator end of the conductive slip ring is connected to the stepper motor to form a fixed part, and the rotor end drives the transducer with six transducer probes arranged.

[0046] As Figure 3 shown, the conductive slip ring is customized and designed with seven coils.

[0047] The stepper motor has a large torque and low temperature rise. It adopts numerical control winding with high consistency. It adopts a circular design in the structural design, which can save space.

[0048] The receiving preprocessing circuit 3 mainly consists of the following three parts:

[0049] A fixed amplification circuit, which selects the AD8222 dual-channel, high-performance instrumentation amplifier to achieve pre-stage impedance matching and fixed gain amplification. To increase the dynamic range of the system as much as possible, the gain setting can be appropriately reduced (10 - 20 dB). The AD8222 adopts a small 4 mm × 4 mm LFCSP package, and the internal structure block diagram of the chip is as Figure 4 shown;

[0050] A voltage-controlled amplification circuit, which selects the 8-channel, ultra-low-power variable gain amplifier VCA8500 with a low-noise preamplifier from TI. The internal functional block diagram of this chip is as Figure 5As shown, the VCA8500 chip incorporates a fixed preamplifier circuit, a programmable attenuation circuit, and a programmable gain amplifier circuit to achieve 46 dB of dynamic gain control;

[0051] For the local oscillator circuit, the dedicated DDS chip AD9834 from Analog Devices, Inc. is selected to generate the local oscillator frequency. The dedicated DDS chip AD9834 from Analog Devices, Inc. can generate a frequency up to 37.5 MHz. Through the configuration of the microcontroller, a fixed frequency of 6 MHz is generated for mixing with the received signal. Then, the I-channel signal and Q-channel signal at the low-frequency end are obtained through a low-pass filter, and data acquisition is achieved through the built-in ADC of the microcontroller. The mixer uses the NE602 mixer from Signetics Corporation, and the cut-off frequency of the low-pass filter is set to 200 kHz. A low-pass filter is built using an operational amplifier to perform signal low-pass filtering.

[0052] As Figure 6 shown, the processing circuit 4 uses the FPGA and MCU as the control cores. Among them, the FPGA selects the XC7A100TCSG FPGA chip of the Artix7 series from Xilinx, and the MCU selects the STM32F407 microcontroller from STMicroelectronics.

[0053] As Figure 7 shown, the transmitting circuit 5 consists of a transmitting excitation signal generation circuit, a power amplifier circuit, and a matching circuit. The transmitting excitation signal generation circuit mainly realizes the required operating frequency, operating pulse width, and operating bandwidth. The main function of the power amplifier circuit is to convert the transmitting excitation signal from a digital PWM signal into an analog signal and then perform power amplification to convert it into a high-voltage signal. The matching circuit mainly realizes the matching of the capacitive reactance and inductive reactance between the transmitting circuit and the transducer to ensure that the transmitted waveform is not distorted.

[0054] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An improved wet end processing device for pipeline sonar, characterized in that, It mainly consists of five parts: a transducer, a conductive slip ring, a stepper motor, a receiving preprocessing circuit, a processing circuit, and a transmitting circuit; the processing circuit is successively connected to the receiving preprocessing circuit, the conductive slip ring and the stepper motor, and the transducer, the processing circuit is successively connected to the transmitting circuit and the conductive slip ring and the stepper motor, and the processing circuit realizes the interaction with the display and control device through the Ethernet interface for the processed data; The cross-section of the housing of the transducer is arranged in a regular hexagon structure, and six transducer probes are evenly distributed on the circumferential surface of the housing of the transducer. The transducer probes are driven by the stepper motor to rotate more than 60 circles within 1 minute; The conductive slip ring is provided with seven coils; The receiving preprocessing circuit mainly consists of three parts: a fixed amplification circuit, a voltage-controlled amplification circuit, and a local oscillator circuit: When the local oscillator circuit works, it is configured by a single-chip microcomputer to generate a fixed frequency of 6 MHz to mix with the received signal, and then through a low-pass filter to realize the I-channel signal and Q-channel signal at the low-frequency end, and then through the built-in ADC of the single-chip microcomputer to realize data acquisition; the cut-off frequency of the low-pass filter is set to 200 kHz, and the low-pass filter is built by an operational amplifier to realize signal low-pass filtering; The processing circuit uses FPGA and MCU as the control core; The processing device increases the sonar operating frequency to 6 MHz, and realizes the horizontal and vertical opening angle resolution of the improved pipeline sonar to be 0.8°; The conductive slip ring is used to transmit electrical signals, and at the same time, its connection can also conduct electricity during relative rotation, and the wires will not be wound. The stator end of the conductive slip ring is connected to the stepper motor to form a fixed part, and the rotor end drives the transducer with six transducer probes arranged; 2. The improved wet end processing device of a pipeline sonar according to claim 1, wherein The stepper motor has large torque and low temperature rise, adopts numerical control winding, has high consistency, and adopts a circular design in the structural design; 3. An improved wet end processing device for pipeline sonar according to claim 1, characterized in that, The transmitting circuit consists of the following three parts: A transmitting excitation signal generation circuit for realizing the original required operating frequency, operating pulse width, and operating bandwidth; A power amplification circuit for realizing the conversion of the transmitting excitation signal from a digital PWM signal to an analog signal, and then realizing power amplification to convert it into a high-voltage signal; A matching circuit for realizing the matching of the capacitive reactance and inductive reactance between the transmitting circuit and the transducer to ensure that the transmitted waveform is not distorted.

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