Water-bearing non-metallic underground pipeline positioning device
By generating vibration wave signals based on the principle of magnetic current effect and analyzing their arrival time, the problem of non-metallic pipeline detection has been solved, and high-precision underground pipeline positioning has been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- UNI TREND TECH (CHINA) CO LTD
- Filing Date
- 2025-09-25
- Publication Date
- 2026-07-10
AI Technical Summary
Existing electromagnetic field induction principles cannot effectively detect non-metallic pipes, especially non-metallic pipes containing water.
The system uses the principle of magnetic current effect to generate periodic vibration wave signals with characteristic frequencies. A transmitter device controls a magnet to reciprocate mechanically inside a non-metallic pipe, striking a metal plate to generate vibration waves. A receiver device captures and analyzes the vibration wave signals to locate the underground pipe.
It has achieved high-precision location and orientation detection of non-metallic underground pipelines with water. By calculating the arrival time and frequency of vibration waves and performing data analysis, the specific location and orientation of the pipeline can be determined.
Smart Images
Figure CN224480573U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of underground pipeline detection technology, specifically to a positioning device for non-metallic underground pipelines with water. Background Technology
[0002] Current underground pipeline detection technology mainly relies on the traditional principle of electromagnetic field induction. However, because non-metallic pipelines lack conductivity and magnetism, these detectors cannot function effectively. Therefore, developing a detection technology suitable for non-metallic pipelines carrying water is of great significance. Utility Model Content
[0003] To overcome the above-mentioned technical problems, this utility model discloses a positioning device for non-metallic underground pipelines with water.
[0004] The technical solution adopted by this utility model to achieve the above objectives is as follows:
[0005] A positioning device for non-metallic underground pipelines with water, comprising a transmitter device and a receiver device;
[0006] The transmitter device includes a speed loop PID control system, a current loop PID control system, and a vibration wave generating mechanism that are electrically connected end to end to form a closed loop. By inputting acceleration information to the speed loop PID control system and current information to the current loop PID control system to generate PWM drive signals, the vibration wave generating mechanism is controlled to emit vibration wave signals.
[0007] The receiver device includes a sensor module, a conditioning circuit, an A / D conversion module, an FPGA, and an embedded system connected in sequence. The FPGA is electrically connected to the conditioning circuit to capture the vibration wave signal, calculate and analyze the arrival time of the vibration wave, and thus realize the location detection of the underground pipeline.
[0008] The aforementioned positioning device for non-metallic underground pipelines with water, wherein the velocity loop PID control system includes an accelerometer, an output acceleration calculation module, and a velocity loop PID connected in sequence. The accelerometer is electrically connected to the vibration wave generating mechanism, and the velocity loop PID is electrically connected to the current loop PID control system.
[0009] The aforementioned positioning device for non-metallic underground pipelines with water includes a current loop PID control system comprising an output current calculation module, a current loop PID, and a current feedback module. The output current calculation module is electrically connected to the speed loop PID. The output current calculation module, the current loop PID, the vibration wave generating mechanism, and the current feedback module are sequentially electrically connected to form a closed loop.
[0010] The aforementioned positioning device for non-metallic underground pipelines with water, wherein the vibration wave generating mechanism includes an electrically connected coil driver, a magnet position detection module, and a vibrator, the coil driver being electrically connected to the current loop PID and the current feedback module, and the magnet position detection module being electrically connected to the accelerometer.
[0011] The above-mentioned positioning device for non-metallic underground pipelines with water, wherein the vibrator includes an inner tube of the vibrator, a coil assembly, a magnet, a metal plate and a rubber pad, and the magnet position detection module is disposed in the inner tube of the vibrator;
[0012] The metal plate and the rubber pad are respectively disposed at both ends of the inner tube of the vibrator to form an impact cavity between them;
[0013] The coil assembly is disposed in the impact cavity. The coil assembly includes at least two sets of coils. Each coil is electrically connected to an excitation source. The coil driver is electrically connected to the excitation source. The magnet moves back and forth in the coil.
[0014] By controlling the start / stop and current direction of the excitation source, and utilizing the principle of magnetic current effect, the magnet is driven to reciprocate mechanically between the impact chambers, so that the magnet strikes the metal plate and generates a vibration wave signal.
[0015] In the aforementioned positioning device for non-metallic underground pipelines with water, the accelerometer, output acceleration calculation module, velocity loop PID, output current calculation module, current loop PID, coil driver, and magnet position detection module are sequentially and electrically connected end to end to form a closed loop.
[0016] In the aforementioned positioning device for non-metallic underground pipelines with water, the output current calculation module, the current loop PID, the coil driver, and the current feedback module are electrically connected end to end in sequence to form a closed loop.
[0017] The aforementioned positioning device for non-metallic underground pipelines with water, wherein the conditioning circuit includes an electrically connected signal amplification module, a frequency selection module, and a filtering module, the signal amplification module being electrically connected to the sensor module, and the filtering module being electrically connected to the A / D conversion module.
[0018] The aforementioned positioning device for non-metallic underground pipelines with water, wherein the embedded system includes an electrically connected MCU, DSP, and RAM, and the FPGA is electrically connected to the MCU to achieve data interaction.
[0019] The aforementioned positioning device for non-metallic underground pipelines with water includes a sensor module comprising a measurement center and four sets of vibration sensors. The four sets of vibration sensors are arranged around the measurement center, and each vibration sensor is equidistant from the measurement center.
[0020] The beneficial effects of this utility model include the following:
[0021] (1) The vibration wave signal with periodic characteristic frequency is generated by adopting the principle of current magnetic effect, and the vibration wave signal is injected into the water-bearing non-metallic underground pipeline. The first arrival time and the second arrival time before and after moving north are calculated. Through data analysis and comparison, the location and direction of the water-bearing non-metallic underground pipeline can be identified and detected.
[0022] (2) The transmitter device adopts dual-loop control of the current loop PID and the speed loop PID to effectively control the output thrust of the coil assembly and the impact speed of the magnet. It uses the principle of current magnetic effect to drive the magnet to perform reciprocating mechanical motion to impact the metal plate and generate vibration waves, producing a high-precision periodic characteristic frequency vibration wave signal. The receiver device receives the vibration wave signal and processes and compares the data before and after moving north to determine the location and direction of the underground pipeline. Attached Figure Description
[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0024] Figure 1 This is a schematic diagram illustrating the principle of the water-bearing non-metallic underground pipeline positioning method of this utility model;
[0025] Figure 2 This is a schematic diagram of the circuit principle of the water-carrying non-metallic underground pipeline positioning device of this utility model;
[0026] Figure 3 This is a schematic diagram (I) illustrating the principle of vibration wave signal generation in this invention.
[0027] Figure 4 Schematic diagram II showing the principle of vibration wave signal generation in this utility model;
[0028] Figure 5 Schematic diagram III showing the principle of vibration wave signal generation in this utility model;
[0029] Figure 6 IV is a schematic diagram illustrating the principle of vibration wave signal generation in this utility model;
[0030] Figure 7 V is a schematic diagram illustrating the principle of vibration wave signal generation in this utility model;
[0031] Figure 8 VI is a schematic diagram illustrating the principle of vibration wave signal generation in this utility model;
[0032] Figure 9This is a schematic diagram of the detection principle in Embodiment 1 of this utility model before moving northward;
[0033] Figure 10 This is a schematic diagram of the detection principle of Embodiment 1 of this utility model after moving northward;
[0034] Figure 11 This is a schematic diagram of the detection principle in Embodiment 2 of this utility model before moving northward;
[0035] Figure 12 This is a schematic diagram of the detection principle in Embodiment 2 of this utility model after moving northward. Detailed Implementation
[0036] The present invention will be further described below through specific embodiments, so as to make the technical solution of the present invention easier to understand and master, rather than to limit the present invention.
[0037] Example: See Figures 1 to 2 This embodiment provides a positioning device for non-metallic underground pipelines with water, which includes a transmitter device and a receiver device;
[0038] The transmitter device includes a speed loop control system, a current loop control system, and a vibration wave generating mechanism that are electrically connected end to end to form a closed loop. By inputting acceleration information to the speed loop control system and current information to the current loop control system to generate PWM drive signals, the vibration wave generating mechanism is controlled to emit vibration wave signals.
[0039] The receiver device includes a sensor module 21, a conditioning circuit 22, an A / D conversion module 23, an FPGA 24, and an embedded system 25, which are electrically connected in sequence. The FPGA 24 is electrically connected to the conditioning circuit 22 to capture the vibration wave signal and calculate and analyze the arrival time of the vibration wave to realize the location detection of the underground pipeline.
[0040] Preferably, the speed loop control system includes an accelerometer 17, an output acceleration calculation module 11, and a speed loop PID 12, which are electrically connected in sequence. The accelerometer 17 is electrically connected to the vibration wave generating mechanism, and the speed loop PID 12 is electrically connected to the current loop control system. The output acceleration calculation module 11 is used to calculate the required output acceleration of the magnet.
[0041] Preferably, the current loop control system includes an output current calculation module 13, a current loop PID 14, and a current feedback module. The output current calculation module 13 is electrically connected to the speed loop PID 12. The output current calculation module 13, the current loop PID 14, the vibration wave generating mechanism, and the current feedback module are sequentially electrically connected to form a closed loop. The output current calculation module 13 is used to calculate the required output current of the coil assembly, and the current feedback module is used to feed back the current output by the coil driver 15 to the output current calculation module 13.
[0042] Preferably, the vibration wave generating mechanism includes a coil driver 15, a magnet position detection module 16, and a vibrator that are electrically connected. The coil driver 15 is electrically connected to the current loop PID 14 and the current feedback module, and the magnet position detection module 16 is electrically connected to the accelerometer 17. The magnet position detection module 16 is used to identify the position of the magnet and feed it back to the accelerometer 17.
[0043] Furthermore, the vibrator includes an inner tube, a coil assembly, a magnet, a metal plate, and a rubber pad, and the magnet position detection module 16 is disposed in the inner tube of the vibrator;
[0044] The metal plate and the rubber pad are respectively disposed at both ends of the inner tube of the vibrator to form an impact cavity between them;
[0045] The coil assembly is disposed in the impact cavity. The coil assembly includes at least two sets of coils. Each coil is electrically connected to an excitation source. The coil driver 15 is electrically connected to the excitation source. The magnet moves back and forth in the coil. The coil assembly is not limited to using two sets of coils to drive the magnet. The number of coils can be set according to the actual use. The magnet can be driven by multiple coils connected in series to obtain greater kinetic energy.
[0046] By controlling the start / stop and current direction of the excitation source, and utilizing the principle of magnetic current effect, the magnet is driven to reciprocate mechanically between the impact chambers, so that the magnet strikes the metal plate and generates a vibration wave signal.
[0047] Specifically, the accelerometer 17, the output acceleration calculation module 11, the velocity loop PID 12, the output current calculation module 13, the current loop PID 14, the coil driver 15, and the magnet position detection module 16 are sequentially electrically connected end to end to form a closed loop;
[0048] The output current calculation module 13, the current loop PID 14, the coil driver 15, and the current feedback module are electrically connected end to end in sequence to form a closed loop.
[0049] Preferably, the conditioning circuit 22 includes a signal amplification module, a frequency selection module, and a filtering module that are electrically connected. The signal amplification module is electrically connected to the sensor module 21, and the filtering module is electrically connected to the A / D conversion module 23. The main function of the conditioning circuit 22 is to receive the vibration wave signal of a specific frequency and filter the vibration wave signal to obtain the target analog signal.
[0050] Specifically, the A / D conversion module 23 converts the preprocessed analog signal into a digital signal and transmits the digital signal in binary code to the embedded system 25 for processing.
[0051] Preferably, the embedded system 25 includes an electrically connected MCU, DSP, and RAM, and the FPGA 24 is electrically connected to the MCU to realize data interaction; the embedded system 25 is the core of processing, execution, calculation, operation, and control, with excellent performance and low power consumption characteristics, and can support complex algorithms, high-speed processing and multi-tasking capabilities, and can meet many different application requirements.
[0052] Preferably, the sensor module 21 includes a measurement center and four sets of vibration sensors, the four sets of vibration sensors being arranged around the measurement center, and each vibration sensor being equidistant from the measurement center.
[0053] Specifically, the vibration wave signal is captured by the sensor module 21. During measurement, the sensor module 21 is parallel to the ground. The sensor module 21 includes four sets of vibration sensors equidistant from the measurement center as measurement points. The measurement center is the origin. Measurement points x1 and x2 are determined according to its east-west direction, and measurement points y1 and y2 are determined according to its north-south direction. That is, the distances of measurement points x1, x2, y1, and y2 from the measurement center are equal.
[0054] Specifically, the transmitter device employs dual-loop control of the current loop PID 14 and the speed loop PID 12 to effectively control the output thrust of the coil assembly and the impact speed of the magnet, thereby generating a high-precision vibration wave signal with a periodic characteristic frequency.
[0055] Preferably, the transmitter device is fixed to a non-metallic pipe. The vibrator utilizes the principle of electric current magnetic effect to drive a magnet in reciprocating mechanical motion, striking the metal plate to generate vibration waves. These vibration waves are then conducted through the non-metallic pipe and the water inside the pipe. The process is as follows:
[0056] (1) See Figure 3 Before the initial moment, the magnet is stationary at the top of the vibrator with the magnetic poles at S on top and N on the bottom.
[0057] From the initial moment, excitation source 1 is turned off, excitation source 2 is turned on and the current direction is upward. According to the magnetic effect of current, a magnetic field with the direction of up (S) and down (N) is generated inside coil 2. Since opposite magnetic poles attract each other, an upward pulling force is generated on the magnet, causing the magnet to accelerate upward. Both coil 1 and coil 2 are helical coils that rotate clockwise from top to bottom.
[0058] (2) See Figure 4 When the magnet enters coil 2 but has not yet reached the top, the excitation source 2 is turned off and the excitation source 1 is turned on with the current direction downward. A magnetic field with the direction of N up and S down is generated inside coil 1. Since like magnetic poles repel each other, they will generate an upward pushing force on the magnet, and the magnet continues to move upward.
[0059] (3) See Figure 5 The magnet continues to rise until it reaches the top rubber pad. The rubber pad restricts the magnet's movement and acts as a buffer to prevent the transmitter from shifting due to excessive impact. The thrust continuously provided by coil 1 keeps the magnet in place at the top rubber pad.
[0060] (4) See Figure 6 When the magnet reaches the position of the top rubber pad, the excitation source 2 is turned off and the excitation source 1 is turned on with the current direction upward. A magnetic field with the direction of up S and down N is generated inside the coil 1. Since opposite magnetic poles attract each other, they will generate a downward pulling force on the magnet, and the magnet begins to move downward.
[0061] (5) See Figure 7 When the magnet enters coil 1 but has not yet reached the bottom, the excitation source 1 is turned off and the excitation source 2 is turned on with the current direction downward. A magnetic field with the direction of N up and S down is generated inside coil 2. Since like magnetic poles repel each other, they will generate a downward pushing force on the magnet, and the magnet will accelerate downward.
[0062] (6) See Figure 8 As coil 2 continues to provide thrust, the magnet continues to accelerate downward until it hits the metal plate at the bottom, thereby generating vibration waves to emit vibration wave signals.
[0063] (7) Repeat the above steps to generate a periodic vibration wave signal.
[0064] Preferably, the transmitter device generates the vibration wave signal by controlling the magnet to repeatedly move and strike the metal plate. In order to obtain the vibration wave signal with a high-precision periodic characteristic frequency, the magnet must be precisely controlled.
[0065] According to the kinetic energy formula Ek=mv 2 / 2, where m is the mass of the object and v is the velocity. Assuming the magnet weighs m = 1 kg, to generate a vibration wave with a power of 1 joule, the velocity upon impact is...
[0066] Given that the inner tube of the vibrator is 1 meter long, the distance the magnet moves is L = 1 meter, and the time it takes for the magnet to go from rest to striking the metal plate is... One cycle of the magnet's reciprocating motion is one period, so the period is... If the magnet moves with uniform acceleration, then the acceleration a = V / t = 1 m / s² 2 According to Newton's second law, F = ma = 1 N, therefore the required force is 1 Newton.
[0067] In summary, to obtain a period of A vibrational wave with a second and an energy of 1 joule requires a force of 1 N to be applied to the magnet. The time, and ensure the speed at impact is
[0068] The formula for the magnetic effect of electric current is known:
[0069]
[0070] B is the magnetic field strength, I is the coil driving current, and r is the perpendicular distance to the wire. According to the formula, the magnetic field strength is directly proportional to the driving current and inversely proportional to the distance. Therefore, the force exerted by the coil magnetic field on the magnet can be controlled by controlling the magnitude of the driving current.
[0071] When this utility model is in operation, it includes the following steps:
[0072] Injecting periodic vibration wave signals with characteristic frequencies into a non-metallic underground pipeline containing water;
[0073] The vibration wave signal is captured, and the arrival time of the vibration wave signal is calculated;
[0074] Based on the characteristic frequency and arrival time of the vibration wave signal, the location and direction of the water-bearing non-metallic underground pipeline are identified.
[0075] Preferably, the calculation of the arrival time of the vibration wave signal specifically includes the following steps:
[0076] Determine the positions of four sets of measurement points equidistant from the measurement center;
[0077] The arrival time of the vibration wave signal at the four sets of measurement points is calculated from the starting point; the starting point is the initial detection point, which can be determined according to the actual measurement situation.
[0078] The measurement point with the longest arrival time is taken as measurement point y1, and measurement point y2 is determined by the north-south direction of the measurement center, and measurement points x1 and x2 are determined by the west-east direction of the measurement center; that is, the measurement point with the longest arrival time is taken as measurement point y1, and then measurement points x1, x2 and y2 are determined according to the preset measurement point distribution rules.
[0079] Based on the positions of the measurement points x1, x2, y1, and y2, the first arrival times Tx1, Tx2, Ty1, and Ty2 of the vibration wave signal reaching the measurement points x1, x2, y1, and y2 are obtained.
[0080] Preferably, identifying the location and direction of the water-bearing non-metallic underground pipeline specifically includes the following steps:
[0081] The measurement center is moved northward, and the second arrival times T'x1 and T'y1 of the vibration wave signal to the measurement points x1 and y1 are calculated according to the first time interval; the first time interval is the time interval between two consecutive calculations of the second arrival time, and can be adjusted according to the actual situation.
[0082] Compare the current second arrival times T'x1 and T'y1 with the previous set of second arrival times T'x1 and T'y1 to determine the change in the distance between the measurement center and the underground pipeline;
[0083] Determine whether the current second arrival times T'x1 and T'y1 are equal to the previous set of second arrival times T'x1 and T'y1;
[0084] If so, the measurement center is determined to be directly above the underground pipeline as the measurement point; specifically, as the measurement center moves northward, the second arrival time T'x1 and T'y1 continuously decrease, and the second arrival time T'x1 and T'y1 are minimized when the measurement center is directly above the underground pipeline.
[0085] Calculate the second arrival times T'x2 and T'y2 of the vibration wave signal at the measurement points x2 and y2, respectively;
[0086] Compare the second arrival times T'x2 and T'y2 with the first arrival times Tx2 and Ty2;
[0087] Determine whether the second arrival times T'x2 and T'y2 are equal to the first arrival times Tx2 and Ty2;
[0088] If so, the underground pipeline is determined to be oriented diagonally; the diagonal direction is from northwest to southeast, from southwest to northeast, from northeast to southwest, or from southeast to northwest.
[0089] If not, the underground pipeline is determined to be in the forward direction; the forward direction is from due north to due south, from due south to due north, from due west to due east, or from due east to due west.
[0090] Preferably, after determining that the underground pipeline runs at an angle, the specific steps include:
[0091] Compare the magnitudes of the second arrival times T'x1 and T'y2, and the magnitudes of the second arrival times T'y1 and T'x2;
[0092] Determine whether the second arrival time T'x1 is equal to the second arrival time T'y2, and whether the second arrival time T'y1 is equal to the second arrival time T'x2; this determination result includes the following two results:
[0093] (1) If so, then the underground pipeline is determined to be located between the measurement points x1 and y2, and between the measurement points y1 and x2;
[0094] Calculate the first difference between the second arrival time T'y1 and T'x1, and the second difference between the second arrival time T'x2 and T'y2;
[0095] Determine whether the first difference is equal to the second difference and is a positive number;
[0096] If so, then the underground pipeline is determined to run from northwest to southeast;
[0097] If so, then the underground pipeline is determined to run from southeast to northwest.
[0098] (2) If not, then the underground pipeline is determined to be located between the measurement points x1 and y1, and between the measurement points y2 and x2;
[0099] Calculate the third difference between the second arrival times T'x1 and T'y2, and the fourth difference between the second arrival times T'y1 and T'x2;
[0100] Determine whether the third difference is equal to the fourth difference and is a positive number;
[0101] If so, then the underground pipeline is determined to run from northeast to southwest;
[0102] If so, then the underground pipeline is determined to run from southwest to northeast.
[0103] Preferably, after determining that the underground pipeline is in a forward direction, the specific steps include:
[0104] Compare the magnitudes of the second arrival times T'y1 and T'y2;
[0105] Determine whether the second arrival time T'y1 is equal to the second arrival time T'y2; this determination result includes the following two results:
[0106] (1) If so, then the underground pipeline is determined to be located between the measurement points y1 and y2;
[0107] Compare the magnitudes of the second arrival time T'x2 and T'x1;
[0108] Determine whether the second arrival time T'x2 is greater than the second arrival time T'x1;
[0109] If so, then the underground pipeline is determined to run from west to east;
[0110] If not, then the underground pipeline is determined to run from east to west.
[0111] (2) If not, then the underground pipeline is determined to be located between the measurement points x1 and x2;
[0112] Compare the magnitudes of the second arrival times T'y1 and T'y2;
[0113] Determine whether the second arrival time T'y1 is greater than the second arrival time T'y2;
[0114] If so, then the underground pipeline is determined to run from north to south;
[0115] If not, then the underground pipeline is determined to run from south to north.
[0116] The following embodiments are described in detail based on the positioning method of this utility model:
[0117] Since the vibration wave propagates along the underground water pipe and spreads in all directions, the propagation speed of the vibration wave in cork is known to be U_wood = 500 m / s, and in water it is U_water = 1500 m / s. The propagation speed in soil is between the speed in cork and the speed in water, and is mainly affected by factors such as soil impurities, density, and water content. Here, we take U_soil = 1000 m / s for calculation (the propagation speed in soil is calculated proportionally, and the specific value does not affect the measurement result).
[0118] Example 1: This example describes the underground pipeline route from due west to due east in detail.
[0119] See Figure 9 Vibration sensors x1, x2, y1, and y2 are located at a distance L1 = 1m from the receiver center (measuring center), and the receiver center is located at a distance L2 = 2m from the water pipe. Therefore, the time it takes for the vibration wave to reach each sensor is:
[0120] Tx1=L2 / U=2 / 1000=0.002=2ms
[0121] Tx2=L2 / U water+L2 / U soil=2 / 1500+2 / 1000=0.00133+0.002=3.33ms
[0122] Ty1=L1 / U water+(L1+L2) / U soil=1 / 1500+3 / 1000=0.00067+0.003=3.67ms
[0123] Ty2 = L1 / Uwater + L1 / Usoil = 1 / 1500 + 1 / 1000 = 0.00067 + 0.001 = 1.67ms
[0124] That is, the vibration wave takes the longest to reach sensor y1, therefore y1 is the farthest from the water pipe.
[0125] See Figure 10 As the receiver moves northward, Ty1, Ty2, Tx1, and Tx2 simultaneously decrease. When the receiver is directly above the water pipe, the time it takes for the vibration wave to reach each sensor is:
[0126] T'y1=T'y2=L1 / U=1 / 1000=1ms
[0127] T'x1 = 0ms
[0128] T'x2=(L1+L1) / Uwater=2 / 1500=1.33ms
[0129] Since T'y1 equals T'y2, meaning the vibration wave takes the same amount of time to reach sensors y1 and y2, it can be concluded that the water pipe is located exactly in the middle of y1 and y2.
[0130] Furthermore, based on T'x1 = 0 ms and T'x2 = 1.33 ms, which means T'x2 is greater than T'x1, it can be concluded that the vibration wave arrives at sensor x1 first and then at sensor x2 1.33 ms later.
[0131] Since sensor x1 is located due west of the center of the sensor and x2 is located due east of the center of the sensor, it can be concluded that the vibration wave is transmitted from west to east.
[0132] Based on this, it can be determined that the water pipe runs from due west to due east.
[0133] Example 2: This example describes the underground pipeline route from northwest to southeast in detail.
[0134] See Figure 11 The vibration sensors x1, x2, y1, and y2 are located at the distances from the receiver center (measurement center). Therefore, the time it takes for the vibration wave to reach each sensor is:
[0135]
[0136] That is, the vibration wave takes the longest to reach sensor y1, therefore y1 is the farthest from the water pipe.
[0137] See Figure 12 As the receiver moves northward, Tx1 and Ty1 decrease simultaneously, while Tx2 and Ty2 remain unchanged. When the receiver is directly above the water pipe, the time it takes for the vibration wave to reach each sensor is:
[0138]
[0139] Since Tx1 equals Ty2, we know that the vibration wave arrives at sensors x1 and y2 at the same time. Therefore, the water pipe is located between x1 and y2. Since Ty1 equals Tx2, we know that the vibration wave arrives at sensors y1 and x2 at the same time. Therefore, the water pipe is also located between y1 and x2. Thus, we know that the water pipe passes through the center of the sensor and is symmetrical along the line from 135° to 315°, i.e., symmetrical from northwest to southeast.
[0140] Since Ty1-Tx1=Tx2-Ty2=0.93ms, we know that the vibration wave first propagates to x1 and y2 simultaneously, and after 0.93ms it propagates along the water pipe to x2 and y1. Therefore, we know that the vibration wave propagates from northwest to southeast.
[0141] Based on this, it can be determined that the water pipe runs from northwest to southeast.
[0142] The method for locating non-metallic underground pipelines with water in this invention has the following advantages:
[0143] (1) The vibration wave signal with periodic characteristic frequency is generated by adopting the principle of current magnetic effect, and the vibration wave signal is injected into the water-bearing non-metallic underground pipeline. The first arrival time and the second arrival time before and after moving north are calculated. Through data analysis and comparison, the location and direction of the water-bearing non-metallic underground pipeline can be identified and detected.
[0144] (2) The transmitter device adopts dual-loop control of the current loop PID and the speed loop PID to effectively control the output thrust of the coil assembly and the impact speed of the magnet. It uses the principle of current magnetic effect to drive the magnet to perform reciprocating mechanical motion to impact the metal plate and generate vibration waves, producing a high-precision periodic characteristic frequency vibration wave signal. The receiver device receives the vibration wave signal and processes and compares the data before and after moving north to determine the location and direction of the underground pipeline.
[0145] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model in any way. Any person skilled in the art can make many possible variations and modifications to the technical solution of this utility model using the disclosed technical means and content, or modify it into equivalent embodiments with equivalent changes, without departing from the scope of the technical solution of this utility model. Therefore, all equivalent changes made based on the shape, structure, and principle of this utility model without departing from its technical solution should be covered within the protection scope of this utility model.
Claims
1. A positioning device for non-metallic underground pipelines with water, characterized in that, It includes a transmitter device and a receiver device; The transmitter device includes a speed loop PID control system, a current loop PID control system, and a vibration wave generating mechanism that are electrically connected end to end to form a closed loop. By inputting acceleration information to the speed loop PID control system and current information to the current loop PID control system to generate PWM drive signals, the vibration wave generating mechanism is controlled to emit vibration wave signals. The receiver device includes a sensor module, a conditioning circuit, an A / D conversion module, an FPGA, and an embedded system connected in sequence. The FPGA is electrically connected to the conditioning circuit to capture the vibration wave signal, calculate and analyze the arrival time of the vibration wave, and thus realize the location detection of the underground pipeline.
2. The positioning device for non-metallic underground pipelines with water as described in claim 1, characterized in that, The velocity loop PID control system includes an accelerometer, an output acceleration calculation module, and a velocity loop PID, which are electrically connected in sequence. The accelerometer is electrically connected to the vibration wave generating mechanism, and the velocity loop PID is electrically connected to the current loop PID control system.
3. The positioning device for non-metallic underground pipelines with water as described in claim 2, characterized in that, The current loop PID control system includes an output current calculation module, a current loop PID, and a current feedback module. The output current calculation module is electrically connected to the speed loop PID. The output current calculation module, the current loop PID, the vibration wave generating mechanism, and the current feedback module are electrically connected in sequence to form a closed loop.
4. The positioning device for non-metallic underground pipelines with water as described in claim 3, characterized in that, The vibration wave generating mechanism includes an electrically connected coil driver, a magnet position detection module, and a vibrator. The coil driver is electrically connected to the current loop PID and the current feedback module, and the magnet position detection module is electrically connected to the accelerometer.
5. The positioning device for non-metallic underground pipelines with water as described in claim 4, characterized in that, The vibrator includes an inner tube, a coil assembly, a magnet, a metal plate, and a rubber pad, and the magnet position detection module is disposed in the inner tube of the vibrator. The metal plate and the rubber pad are respectively disposed at both ends of the inner tube of the vibrator to form an impact cavity between them; The coil assembly is disposed in the impact cavity. The coil assembly includes at least two sets of coils. Each coil is electrically connected to an excitation source. The coil driver is electrically connected to the excitation source. The magnet moves back and forth in the coil. By controlling the start / stop and current direction of the excitation source, and utilizing the principle of magnetic current effect, the magnet is driven to reciprocate mechanically between the impact chambers, so that the magnet strikes the metal plate and generates a vibration wave signal.
6. The positioning device for non-metallic underground pipelines with water as described in claim 5, characterized in that, The accelerometer, output acceleration calculation module, velocity loop PID, output current calculation module, current loop PID, coil driver and magnet position detection module are electrically connected end to end in sequence to form a closed loop.
7. The positioning device for non-metallic underground pipelines with water as described in claim 6, characterized in that, The output current calculation module, current loop PID, coil driver and current feedback module are electrically connected end to end to form a closed loop.
8. The positioning device for non-metallic underground pipelines with water as described in claim 1, characterized in that, The conditioning circuit includes a signal amplification module, a frequency selection module, and a filtering module that are electrically connected. The signal amplification module is electrically connected to the sensor module, and the filtering module is electrically connected to the A / D conversion module.
9. The positioning device for non-metallic underground pipelines with water as described in claim 8, characterized in that, The embedded system includes an electrically connected MCU, DSP, and RAM, and the FPGA is electrically connected to the MCU to enable data interaction.
10. The positioning device for non-metallic underground pipelines with water as described in claim 9, characterized in that, The sensor module includes a measurement center and four sets of vibration sensors. The four sets of vibration sensors are arranged around the measurement center, and each vibration sensor is equidistant from the measurement center.