An ultrasonic ranging device, system and method for two media

Abstract

The present invention discloses an ultrasonic ranging device, system and method for two media. The device includes a microprocessor, a power amplification unit, an echo conditioning unit and an ultrasonic transducer; the microprocessor generates a square wave pulse signal with a preset frequency, the power amplification unit processes and amplifies the power of the square wave pulse signal to generate a driving signal to drive the ultrasonic transducer to emit an ultrasonic signal into the first medium or the second medium; the ultrasonic transducer receives the echo returned through the first medium and generates a first echo signal, or the echo returned through the second medium to generate a second echo signal, the echo conditioning unit processes the first echo signal or the second echo signal to generate a first analog signal or a second analog signal and sends it to the microprocessor, and the microprocessor calculates the distance according to the first analog signal or the second analog signal; this solution can meet the ranging requirements of two media with only one ultrasonic transducer.

Description

Technical Field

[0001] The present invention relates to the technical field of ranging, and particularly to an ultrasonic ranging device, system and method for two media. Background Art

[0002] When there are huge differences in the characteristics (such as density, sound velocity) of the ultrasonic transmission medium, there will be great differences in the power that the ultrasonic transducer can radiate and the intensity of the echo signal. This determines that the ultrasonic transducer can usually only be designed and used for a specific medium, that is: the ultrasonic ranging transducer dedicated to air can only be used for ranging in air and cannot be used for underwater ranging, and vice versa. Therefore, it is difficult for an ultrasonic transducer for a certain specific medium type to meet the ranging requirements under two media at the same time, such as the ranging requirements in air and underwater. In addition, since the propagation speeds of ultrasonic waves in air and water are about 340 m / s and 1500 m / s respectively, such a large difference in propagation speed also increases the difficulty of designing the ultrasonic emission and echo detection system.

[0003] Existing ultrasonic ranging is usually for applications in the same medium scenario. Most cases are in air, and a small number are in underwater or other liquid applications. In some scenarios, such as in the detection of bored pile hole formation, ranging in air and underwater needs to be completed successively during a single detection process. To solve the ranging problem in the two environmental conditions of air and underwater, there are generally two forms: double probes and composite probes. The double-probe scheme is to select two ultrasonic transducers respectively suitable for the air and underwater detection environments, and design two probes separately. The underwater probe is not used when detecting in the air environment, and the probe for detecting in the air environment does not go underwater. In double-probe ranging, a towing system needs to be configured for each of the two probes, and the position of the water surface needs to be accurately determined to achieve it. At the same time, it will cause the ranging system to be too complex in structure and too costly, making it difficult to implement in engineering.

[0004] The composite-probe scheme still needs to select two transducers for the air and underwater detection environments respectively. The difference from the double-probe scheme is that after waterproof modification of the transducer for detecting in air, it is combined with the transducer for detecting in underwater into a whole probe that can go underwater in structure, thereby simplifying the structure of the towing system. To implement this scheme, it is necessary to modify the transducer suitable for the air medium to make it have an IP68 protection level and be able to withstand sufficient water pressure. However, the modified transducer is very likely to not meet the detection requirements in air. Therefore, this scheme not only does not improve in terms of the complexity of the probe, but also has relatively large problems in terms of feasibility.

[0005] Patent text CN209689617 U discloses a dual-probe water depth measuring device, which includes a housing, a laser ranging sensor, an ultrasonic ranging module, an STM32 development board, and a gyroscope; the STM32 development board and the gyroscope are both fixedly arranged inside the housing, the laser ranging sensor and the ultrasonic ranging module are respectively arranged on the housing, and the laser emission direction of the laser ranging sensor and the ultrasonic emission direction of the ultrasonic ranging module are parallel and non-coaxial; the laser ranging sensor, the ultrasonic ranging module, and the gyroscope are respectively electrically connected to the STM32 development board. This solution realizes water depth detection by setting two probes of laser and ultrasonic, however, this solution also has problems of complex system structure and high cost. Summary of the Invention

[0006] The present invention provides an ultrasonic ranging device, system and method for two media, which are applicable to ultrasonic ranging in two media and can reduce the complexity of the system structure, thereby reducing the production cost.

[0007] An ultrasonic ranging device for two media includes a microprocessor, a power amplification unit, an echo conditioning unit, and an ultrasonic transducer;

[0008] The microprocessor is used to generate a square wave pulse signal with a preset frequency according to the received ranging request and send it to the power amplification unit. The power amplification unit processes and amplifies the power of the square wave pulse signal to generate a driving signal, and the ultrasonic transducer emits an ultrasonic signal to the first medium or the second medium according to the driving signal;

[0009] The ultrasonic transducer receives the echo returned by the first medium and generates a first echo signal, or the echo returned by the second medium generates a second echo signal, and sends the first echo signal or the second echo signal to the echo conditioning unit. The echo conditioning unit processes the first echo signal or the second echo signal to generate a first analog signal or a second analog signal and sends it to the microprocessor, and the microprocessor calculates the distance according to the first analog signal or the second analog signal;

[0010] Wherein, the ultrasonic transducer is adapted to the medium with a larger density among the first medium and the second medium.

[0011] Further, the device further includes a power supply module, and the power supply module is connected to the microprocessor, the power amplification unit, and the echo conditioning unit.

[0012] Further, the density of the first medium is less than the density of the second medium;

[0013] The echo conditioning unit includes a first echo conditioning unit and a second echo conditioning unit. When the first echo conditioning unit and the second echo conditioning unit receive the first echo signal, the second echo conditioning unit is cut off, and the first echo conditioning unit processes the first echo signal to generate the first analog signal. When the first echo conditioning unit and the second echo conditioning unit receive the second echo signal, the first echo conditioning unit outputs in saturation, and the second echo conditioning unit processes the second analog signal to generate the second analog signal.

[0014] Further, the first echo conditioning unit includes a pre-amplification module, a band-pass filtering module, a first detection module, a post-amplification module, and a first low-pass filtering module connected in sequence. The pre-amplification module is used to perform pre-amplification on the first echo signal and send the first echo signal after pre-amplification to the band-pass filtering module. The band-pass filtering module filters out background noise from the first echo signal after pre-amplification. The first detection module is used to perform unipolar conversion on the first echo signal output by the band-pass filtering module and send it to the post-amplification module. The post-amplification module performs re-amplification processing on the received unipolar-converted first echo signal and sends it to the first low-pass filtering module. The first low-pass filtering module is used to filter the received first echo signal after re-amplification processing to generate the first analog signal.

[0015] Further, the second echo conditioning unit includes a second detection module, a proportional amplification module, and a second low-pass filtering module. The second detection module performs unipolar conversion on the second echo signal. The proportional amplification module amplifies the unipolar-converted second echo signal. The second low-pass filtering module filters the amplified second echo signal to generate the second analog signal.

[0016] Further, the power amplification unit includes a driving module and a boosting module. The driving module amplifies the square wave pulse signal. The boosting module is used to boost the amplified square wave pulse signal to generate the driving signal.

[0017] Further, the ultrasonic transducer includes a transmitter and a receiver. The transmitter emits an ultrasonic signal to the first medium or the second medium according to the driving signal. The receiver receives the first echo signal returned from the first medium or the second echo signal returned from the second medium and sends it to the echo conditioning unit.

[0018] The transmitter and the receiver are integrally designed or separately designed.

[0019] An ultrasonic ranging system for two media, comprising an ultrasonic probe body and at least one set of the above ultrasonic ranging devices, and at least one set of the ultrasonic ranging devices are distributed on the ultrasonic probe body.

[0020] An ultrasonic ranging method for two media using the above device, comprising:

[0021] The microprocessor generates a square wave pulse signal with a preset frequency according to the received ranging request and sends it to the power amplification unit;

[0022] The power amplification unit processes and amplifies the power of the square wave pulse signal to generate a driving signal, and the ultrasonic transducer emits an ultrasonic signal to the first medium or the second medium according to the driving signal;

[0023] The ultrasonic transducer receives the echo returned by the first medium and generates a first echo signal, or the echo returned by the second medium generates a second echo signal, and sends the first echo signal or the second echo signal to the echo conditioning unit;

[0024] The echo conditioning unit processes the first echo signal or the second echo signal to generate a first analog signal or a second analog signal and sends it to the microprocessor, and the microprocessor calculates the distance according to the first analog signal or the second analog signal;

[0025] Wherein, the ultrasonic transducer is adapted to the one with a larger density among the first medium and the second medium.

[0026] Further, the density of the first medium is less than the density of the second medium; the echo conditioning unit includes a first echo conditioning unit and a second echo conditioning unit;

[0027] The echo conditioning unit processes the first echo signal or the second echo signal to generate a first analog signal or a second analog signal, including:

[0028] When the first echo conditioning unit and the second echo conditioning unit receive the first echo signal, the second echo conditioning unit is cut off, and the first echo conditioning unit processes the first echo signal to generate the first analog signal;

[0029] When the first echo conditioning unit and the second echo conditioning unit receive the second echo signal, the first echo conditioning unit outputs saturatedly, and the second echo conditioning unit processes the second analog signal to generate the second analog signal.

[0030] The ultrasonic ranging device, system and method for two media provided by the present invention have at least the following beneficial effects:

[0031] (1) An ultrasonic transducer adapted to a relatively high-density medium is adopted. Through different echo processing, only one type of ultrasonic transducer can meet the application requirements for ranging in two media, thereby simplifying the structure of the device and reducing production costs.

[0032] (2) Signal amplification processing of the echoes returned from different media is achieved through the first echo signal conditioning circuit and the second echo signal conditioning circuit. On the one hand, only one type of ultrasonic transducer can meet the application requirements for ranging in two media. On the other hand, when the first echo conditioning unit and the second echo conditioning unit receive the first echo signal returned from the first medium, the second echo conditioning unit is cut off. When the first echo conditioning unit and the second echo conditioning unit receive the second echo signal returned from the second medium, the first echo conditioning unit outputs saturatedly, realizing the self-adaptation of echo signal processing in different media. Description of the Drawings

[0033] Figure 1 It is a schematic structural diagram of an embodiment of the ultrasonic ranging device for two media provided by the present invention.

[0034] Figure 2 It is a schematic structural diagram of another embodiment of the ultrasonic ranging device for two media provided by the present invention.

[0035] Figure 3 It is a schematic structural diagram of an embodiment of the first echo conditioning unit in the ultrasonic ranging device for two media provided by the present invention.

[0036] Figure 4 It is a circuit diagram of an embodiment of the first echo conditioning unit in the ultrasonic ranging device for two media provided by the present invention.

[0037] Figure 5 It is a schematic structural diagram of an embodiment of the second echo conditioning unit in the ultrasonic ranging device for two media provided by the present invention.

[0038] Figure 6 It is a circuit diagram of an embodiment of the second echo conditioning unit in the ultrasonic ranging device for two media provided by the present invention.

[0039] Figure 7 It is a schematic structural diagram of an embodiment of the power amplification unit in the ultrasonic ranging device for two media provided by the present invention.

[0040] Figure 8 It is a circuit diagram of an embodiment of the power amplification unit in the ultrasonic ranging device for two media provided by the present invention.

[0041] Figure 9 Waveform diagram for underwater ranging by the ultrasonic ranging device for two media provided by the present invention.

[0042] Figure 10 Waveform diagram for ranging in air by the ultrasonic ranging device for two media provided by the present invention.

[0043] Figure 11 Schematic structural diagram of an embodiment of the ultrasonic ranging system for two media provided by the present invention.

[0044] Figure 12 Flowchart of an embodiment of the ultrasonic ranging method for two media provided by the present invention. Detailed implementation manners

[0045] In order to better understand the above technical solutions, the above technical solutions will be described in detail below in conjunction with the accompanying drawings of the specification and specific implementation manners.

[0046] The principle of ultrasonic ranging is as follows: At the detection start time t0, the microprocessor emits a square wave pulse train with a certain frequency and a certain number of waves, which is amplified by power and drives the ultrasonic transmitter to emit ultrasonic waves; when the ultrasonic waves are transmitted through the medium and encounter an obstacle (the hole wall), a reflection phenomenon occurs, forming an echo; the echo is transmitted through the medium and reaches the ultrasonic receiver, and the ultrasonic receiver outputs an echo signal; after the echo signal is processed by the signal conditioning unit, a pulse signal available for the microprocessor is formed to determine the stop time t1 of timing; from the difference between the detection stop time t1 and the detection start time t0, and the wave speed c of the transmission medium r , the distance to be measured can be calculated, x = 0.5c r (t1 - t0).

[0047] Whether the ranging function can be realized depends on: ① whether the ultrasonic transmitter can radiate ultrasonic waves with sufficient intensity; ② the reflection effect of the obstacle; ③ the sensitivity of the ultrasonic receiver; ④ the performance of the echo conditioning unit. Among them, the reflection effect of the obstacle is determined by the application scenario and is difficult to change through technical means, so it is not included in the scope of discussion of this embodiment.

[0048] The ultrasonic power that the ultrasonic transmitter can radiate is jointly determined by the ultrasonic transducer and the characteristics such as the density and wave speed of the medium. The densities of air and water are approximately 1.293 kg / m 3 and 103 kg / m 3 , with a difference of nearly 800 times; the sound speeds of air and water are approximately 340 m / s and 1480 m / s respectively, with a difference of nearly 5 times. The quantity used to comprehensively reflect the influence of these two parameters is the acoustic impedance Zr = ρ r c r, which is the product of density and sound velocity, differs by approximately 34,120 times. Therefore, from the perspective of acoustic impedance, for ultrasonic transducers of the same model, the radiation power in air and water will differ by several orders of magnitude. Even without considering other factors, when ranging in two media, the intensity of the echo signal will inevitably also differ by several orders of magnitude.

[0049] The above phenomenon can also be revealed at the microscopic level. Ultrasonic transducers radiate power by "squeezing" the medium during the physical vibration process. This power is determined by the vibration velocity (manifested as frequency), vibration amplitude, the area of the vibration surface, and the mass per unit volume of the medium (i.e., density). Therefore, transducers dedicated for use in air usually have a large amplitude to push the very low-density air; the vibrating elements are relatively thin and light to generate sufficient amplitude at a relatively low echo power to output the required echo signal; underwater-dedicated transducers usually only require a small amplitude to push the very high-density water to radiate sufficient power; the vibrating elements are relatively thick, but since the echo power is high enough, the vibrating elements of the receiver only need a very small amplitude to output the required echo signal.

[0050] When an underwater-dedicated transducer is used in air, due to the very low density of air, a tiny amplitude can only radiate a very low level of power, and it is difficult for the receiver to generate sufficient vibration amplitude to output a signal that is easy to process. When a transducer dedicated for use in air is placed underwater, although the designed amplitude is large, it is for pushing air and cannot generate effective vibrations underwater.

[0051] Therefore, based on the above discussion, the following conclusions can be summarized: ① Ultrasonic transducers are usually designed for specific applications in a medium; ② When the transducer and the medium do not match, the echo signal will be greatly affected and may even be difficult to apply; ③ In the ranging application of transducers, the performance of the transmitter and the receiver usually needs to be fully matched.

[0052] Reference Figure 1 , in some embodiments, to solve the above problems, an ultrasonic ranging device for two media is provided, including a microprocessor 1, a power amplification unit 2, an echo conditioning unit 3, and an ultrasonic transducer 4;

[0053] The microprocessor 1 is configured to generate a square wave pulse signal with a preset frequency according to the received ranging request and send it to the power amplification unit 2. The power amplification unit 2 processes and amplifies the power of the square wave pulse signal to generate a driving signal. The ultrasonic transducer 4 emits an ultrasonic signal to the first medium or the second medium according to the driving signal;

[0054] The ultrasonic transducer 4 receives the echo returned through the first medium and generates a first echo signal, or the echo returned through the second medium to generate a second echo signal, and sends the first echo signal or the second echo signal to the echo conditioning unit 3. The echo conditioning unit 3 processes the first echo signal or the second echo signal to generate a first analog signal or a second analog signal and sends it to the microprocessor 1. The microprocessor 1 calculates the distance based on the first analog signal or the second analog signal;

[0055] Among them, the ultrasonic transducer 4 is adapted to the medium with a higher density among the first medium and the second medium.

[0056] The ultrasonic transducer 4 is adapted to the medium with a higher density among the first medium and the second medium, that is, the structure of the ultrasonic transducer, the amplitude of the oscillation element, and the driving power are all applicable to the medium with a higher density among the two media under normal circumstances. However, the reverse is not true. If an ultrasonic transducer adapted to the medium with a lower density among the two media is used, the amplitude of the oscillation element is larger, but the driving force is weak and the rated output power is small, and it cannot emit enough power in the medium with a higher density.

[0057] Further, in some embodiments, the device further includes a power supply module 5. The power supply module 4 is connected to the microprocessor 1, the power amplification unit 2, and the echo conditioning unit 3, and the power supply module 5 provides electrical energy for each module.

[0058] In some embodiments, the first medium and the second medium are two media with large differences in properties such as density and sound velocity, such as air and water (including muddy water).

[0059] In some embodiments, the density of the first medium is less than the density of the second medium. For example, the first medium may be air and the second medium may be water. The following technical solutions will be described with the density of the first medium being less than the density of the second medium.

[0060] Further, referring to Figure 2 , the echo conditioning unit 3 includes a first echo conditioning unit 31 and a second echo conditioning unit 32. When the first echo conditioning unit 31 and the second echo conditioning unit 32 receive the first echo signal returned through the first medium, the second echo conditioning unit 32 is cut off, and the first echo conditioning unit 31 processes the first echo signal to generate the first analog signal; when the first echo conditioning unit 31 and the second echo conditioning unit 32 receive the second echo signal, the first echo conditioning unit 31 outputs in saturation, and the second echo conditioning unit 32 processes the second analog signal to generate the second analog signal.

[0061] Specifically, the density of the first medium is less than that of the second medium. For the first echo signal returning from the first medium with a smaller density, its signal intensity is weak and the signal-to-noise ratio is low, which causes the second echo conditioning unit 32 to cut off, and the first echo conditioning unit 31 processes the first echo signal to generate the first analog signal. For the second echo signal returning from the second medium with a larger density, the signal is stronger and the signal-to-noise ratio is high, which causes the first echo conditioning unit 31 to saturate and output. The second echo conditioning unit 32 processes the second analog signal to generate the second analog signal. In this way, only one ultrasonic transducer can meet the application requirements of ranging in two media and achieve the self-adaptation of echo signal processing in different media. In addition, the judgment function of medium self-adaptation can be used to further adjust the frequency and intensity of ultrasonic emission, so as to obtain a stronger echo signal.

[0062] Further, referring to Figure 3 , the first echo conditioning unit 31 includes a pre-amplification module 31a, a band-pass filtering module 31b, a first detection module 31c, a post-amplification module 31d, and a first low-pass filtering module 31e connected in sequence. The pre-amplification module 31a is used to perform pre-amplification on the first echo signal and send the first echo signal after pre-amplification to the band-pass filtering module 31b. The band-pass filtering module 31b filters out background noise from the first echo signal after pre-amplification. The first detection module 31c is used to perform unipolar conversion on the first echo signal output by the band-pass filtering module 31b and send it to the post-amplification module 31d. The post-amplification module 31d performs re-amplification processing on the received unipolar-converted first echo signal and sends it to the first low-pass filtering module. The first low-pass filtering module is used to filter the received first echo signal after re-amplification processing to generate the first analog signal.

[0063] Referring to Figure 4 , in some embodiments, the pre-amplification module 31a includes an instrumentation amplifier U1 and a variable resistor R G , the instrumentation amplifier U1 and the variable resistor R G constitute a gain-programmable amplifier to perform pre-amplification on the first echo signal. By adjusting the resistance value of the variable resistor R G , a gain of 1 to 50 times can be obtained to meet the need for signal amplification in the range of 1 to 200 mV, and it has a very high input impedance, a very wide frequency band, small temperature drift, and high precision. Among them, the non-inverting input terminal of the instrumentation amplifier U1 is connected to the ultrasonic transducer 4, the Gp terminal and the Gn terminal of the instrumentation amplifier U1 are connected to the variable resistor RG, and the output terminal of the instrumentation amplifier U1 is connected to the band-pass filtering module 31b.

[0064] Further, the band-pass filtering module 31b includes a filter U2. The input end of the filter U2 is connected to the output end of the instrumentation amplifier U1 in the pre-stage amplification module 31a, and the output end of the filter U2 is connected to the first detection module 31c. In order to eliminate the noise amplified by the pre-stage amplification module simultaneously to improve the signal-to-noise ratio, a band-pass filter with a center frequency identical to the excitation signal frequency is formed by using the filter U2, so as to filter out the background noise to the greatest extent.

[0065] Further, the first detection module 31c includes a first operational amplifier Q1, a second operational amplifier Q2, a first resistor R1, a second resistor R2, a third resistor R3, a first diode D1, a second diode D2, a third diode D3, and a fourth diode D4. The output end of the band-pass filtering module 31b is connected to the inverting input end of the first operational amplifier Q1 and the non-inverting input end of the second operational amplifier Q2. The first resistor R1 is connected between the output end of the band-pass filtering module 31b and the inverting input end of the first operational amplifier Q1. The anode of the first diode D1 is connected to the inverting input end of the first operational amplifier Q1, and the cathode is connected to the output end of the first operational amplifier Q1. The anode of the fourth diode D4 is connected to the inverting input end of the second operational amplifier Q2, and the cathode is connected to the output end of the second operational amplifier Q2. The second resistor R2 is connected to the inverting input end and the output end of the first operational amplifier Q1. The third resistor R3 is connected to the inverting input end and the output end of the second operational amplifier Q2. The anode of the second diode D2 is connected to the output end of the first operational amplifier Q1, and the anode of the third diode D3 is connected to the output end of the second operational amplifier Q2. The output ends of the first operational amplifier Q1 and the second operational amplifier Q2 constitute the output end of the first detection module 31c.

[0066] Further, the post-stage amplification module 31d includes a third operational amplifier Q3, a fourth resistor R4, a fifth resistor R5, and a sixth resistor. One end of the fourth resistor R4 is connected to the output end of the first detection module 31c, and the other end is connected to the non-inverting input end of the third operational amplifier Q3. One end of the fifth resistor R5 is connected to the inverting input end of the third operational amplifier Q3, and the other end is grounded. One end of the sixth resistor R6 is connected to the inverting input end of the third operational amplifier Q3, and the other end is connected to the output end of the third operational amplifier Q3.

[0067] The fixed-gain amplification link formed by the third operational amplifier Q3 and its peripheral resistors has a gain that can be set between 1 and 20, and further amplifies the first echo signal.

[0068] Further, the first low-pass filtering module 31e includes a fourth operational amplifier Q4, a seventh resistor R7, and a first capacitor C1. One end of the seventh resistor R7 is connected to the output end of the third operational amplifier Q3, and the other end is connected to the non-inverting input end of the fourth operational amplifier Q4. One end of the first capacitor C1 is connected to the non-inverting input end of the fourth operational amplifier Q4, and the other end is grounded.

[0069] The first low-pass filtering module 31e is used to filter out the excitation frequency component in the first echo signal and finally output the first analog signal that can be used for A / D conversion in the form of an envelope.

[0070] In summary, the first echo conditioning unit 31 processes the first echo signal to generate the first analog signal and sends it to the microprocessor 1 for the next step of distance calculation based on the first medium. If the first echo conditioning unit 31 receives the second echo signal, due to the large gain of the first echo conditioning unit 31, its output signal is in a saturated state and no echo pulse will appear.

[0071] Further, referring to Figure 5 , the second echo conditioning unit 32 includes a second detection module 32a, a proportional amplification module 32b, and a second low-pass filtering module 32c. The second detection module 32a performs unipolar conversion on the second echo signal, the proportional amplification module 32b amplifies the unipolar-converted second echo signal, and the second low-pass filtering module 32c filters the amplified second echo signal to generate the second analog signal.

[0072] Referring to Figure 6 , the second detection module 32a includes a fifth diode D5, a sixth diode D6, an eighth resistor R8, and a ninth resistor R9. The cathode of the fifth diode D5 and the anode of the sixth diode D6 form the input end of the second detection module 32a. The anode of the fifth diode D5 is connected to one end of the eighth resistor R8, the other end of the eighth resistor R8 is grounded, the cathode of the sixth diode D6 is connected to one end of the ninth resistor R9, the other end of the ninth resistor R9 is grounded, and the output end of the second detection module 32a is led out between the ninth resistor R9 and the sixth diode D6.

[0073] Among them, the fifth diode D5 and the sixth diode D6 are high-frequency Schottky diodes, and the conduction threshold can be set as needed. If the second echo signal returned from the second medium with higher density is received, it will conduct. If the weaker first echo signal is received and the conduction threshold is not reached, the fifth diode D5 and the sixth diode D6 will be cut off, making the output signal of the entire second echo conditioning unit 32 zero and no echo pulse will appear, thus realizing the adaptability of echo signal processing under different media.

[0074] Further, the ratio amplification module 32b includes a fifth operational amplifier Q5, a tenth resistor R10, an eleventh resistor R11, and a twelfth resistor R12. One end of the tenth resistor R10 is connected to the output end of the second detection module 32a, and the other end is connected to the non-inverting input terminal of the fifth operational amplifier Q5. One end of the eleventh resistor R11 is connected to the inverting input terminal of the fifth operational amplifier Q5, and one end of the twelfth resistor R12 is connected to the inverting input terminal of the fifth operational amplifier Q5, and the other end is connected to the output end of the fifth operational amplifier Q5.

[0075] Further, the second low-pass filtering module 32c includes a sixth operational amplifier Q6, a thirteenth resistor R13, and a second capacitor C2. One end of the thirteenth resistor R13 is connected to the output end of the sixth operational amplifier Q6, and the other end is connected to the non-inverting input terminal of the sixth operational amplifier Q6. One end of the second capacitor C2 is connected to the non-inverting input terminal of the sixth operational amplifier Q6, and the other end is grounded.

[0076] Further, refer to Figure 7 , the power amplification unit 2 includes a driving module 21 and a boosting module 22. The driving module 21 amplifies the square wave pulse signal, and the boosting module 22 is used to boost the amplified square wave pulse signal to generate the driving signal.

[0077] Specifically, refer to Figure 8 , the driving module 21 includes a MOS transistor driving chip U3, a first NMOS transistor p1, and a second NMOS transistor p2. The first NMOS transistor p1 and the second NMOS transistor p2 are respectively connected to the output end of the MOS transistor driving chip U3.

[0078] The boosting module 22 includes a transformer T and a third capacitor C3. The primary coil of the transformer T is connected to the first NMOS transistor and the second NMOS transistor, the secondary coil is connected to the ultrasonic transducer 4, and one end of the third capacitor C3 is connected to the middle contact of the primary coil, and the other end is grounded.

[0079] The square wave pulse signal generated by the microprocessor 1 is amplified by the MOS transistor driving chip U3 to drive the first NMOS transistor and the second NMOS transistor, and a voltage of about 700VPP is generated through the transformer T with a turns ratio of 1:30, so that the ultrasonic transducer generates an ultrasonic signal.

[0080] In some embodiments, the ultrasonic transducer 4 includes a transmitter and a receiver. The transmitter emits an ultrasonic signal to the first medium or the second medium according to the driving signal; the receiver receives the first echo signal returned by the first medium or the second echo signal returned by the second medium and sends it to the echo conditioning unit;

[0081] The transmitter and the receiver can be designed as an integrated unit or as separate units.

[0082] The following further illustrates the device provided in this embodiment through specific application scenarios.

[0083] Taking the distance to be measured of 400 mm in air and underwater as an example, Figure 9 In the middle is the waveform diagram of underwater distance measurement, Figure 10 is the waveform diagram of distance measurement in air. Among them, waveform 1 is a square wave pulse signal, waveform 2 is the signal output by the first echo conditioning unit, and waveform 3 is the signal output by the second echo conditioning unit. Refer to Figure 9 , in water and air, the time differences between the first echo signal or the second echo signal and the square wave pulse signal are 529 μs and 2.35 ms respectively. Converted according to the wave speeds of 1480 m / s and 340 m / s respectively, the distance detection results are 391.5 mm and 399.5 mm, which are very close to the set 400 mm;

[0084] During underwater distance measurement, the first echo signal keeps rising until saturation; during air distance measurement, the second echo signal is always in the 0V state except for being affected by the excitation pulse crosstalk; neither of them has a pulse corresponding to the echo.

[0085] The ultrasonic distance measurement device for two media provided in the above embodiment has at least the following beneficial effects:

[0086] (1) By using an ultrasonic transducer adapted to a medium with a relatively large density and through different echo processing, only one ultrasonic transducer can meet the application requirements of distance measurement in two media, thus simplifying the structure of the device and further reducing the production cost;

[0087] (2) Through the first echo signal conditioning circuit and the second echo signal conditioning circuit, signal amplification processing of the echoes returned from different media is realized. On the one hand, only one ultrasonic transducer can meet the application requirements of distance measurement in two media. On the other hand, when the first echo conditioning unit and the second echo conditioning unit receive the first echo signal returned from the first medium, the second echo conditioning unit is cut off. When the first echo conditioning unit and the second echo conditioning unit receive the second echo signal returned from the second medium, the first echo conditioning unit outputs saturated, realizing the self - adaptation of echo signal processing in different media.

[0088] Refer to Figure 11 , in some embodiments, a ultrasonic distance measurement system for two media is provided, including an ultrasonic probe body 100 and at least one set of the above - mentioned ultrasonic distance measurement device 200. At least one set of ultrasonic distance measurement devices 200 is distributed on the ultrasonic probe body 100.

[0089] The above system is applied to the detection of the hole diameter of cast-in-place piles, and may also include a probe dragging mechanism (winch), a measurement and control host, a data recording and analyzing instrument, etc. A plurality of ultrasonic ranging devices are uniformly arranged on different azimuths of the ultrasonic probe body in a split transmitting and receiving or integrated transmitting and receiving manner, for detecting the distance from the probe center to the hole wall and realizing the adaptive calibration of the probe center position. The position of the ultrasonic probe body in the axial direction of the hole is controlled by the winch dragging, and the position information is fed back through the rotary encoder inside the winch, serving as the basis for detecting the hole depth and the thickness of sediment.

[0090] Reference Figure 12 , in some embodiments, there is provided an ultrasonic ranging method for two media using the above device, including:

[0091] S1. The microprocessor generates a square wave pulse signal with a preset frequency according to the received ranging request and sends it to the power amplification unit;

[0092] S2. The power amplification unit processes and amplifies the power of the square wave pulse signal to generate a driving signal, and the ultrasonic transducer emits an ultrasonic signal to the first medium or the second medium according to the driving signal;

[0093] S3. The ultrasonic transducer receives the echo returned by the first medium and generates a first echo signal, or the echo returned by the second medium generates a second echo signal, and sends the first echo signal or the second echo signal to the echo conditioning unit;

[0094] S4. The echo conditioning unit processes the first echo signal or the second echo signal to generate a first analog signal or a second analog signal and sends it to the microprocessor, and the microprocessor calculates the distance according to the first analog signal or the second analog signal;

[0095] Wherein, the ultrasonic transducer is adapted to the medium with a larger density among the first medium and the second medium.

[0096] Further, the density of the first medium is less than the density of the second medium; the echo conditioning unit includes a first echo conditioning unit and a second echo conditioning unit;

[0097] In step S4, the echo conditioning unit processes the first echo signal or the second echo signal to generate a first analog signal or a second analog signal, including:

[0098] S41. When the first echo conditioning unit and the second echo conditioning unit receive the first echo signal, the second echo conditioning unit is cut off, and the first echo conditioning unit processes the first echo signal to generate the first analog signal;

[0099] S42. When the first echo conditioning unit and the second echo conditioning unit receive the second echo signal, the first echo conditioning unit outputs in saturation, and the second echo conditioning unit processes the second analog signal to generate the second analog signal.

[0100] The ultrasonic ranging method for two media provided by the present invention has at least the following beneficial effects:

[0101] (1) By using an ultrasonic transducer adapted to a relatively large-density medium and through different echo processing, only one ultrasonic transducer can meet the application requirements for ranging in two media, thus simplifying the structure of the device and further reducing the production cost;

[0102] (2) The signal amplification processing of the echoes returned by different media is realized through the first echo signal conditioning circuit and the second echo signal conditioning circuit. On the one hand, only one ultrasonic transducer can meet the application requirements for ranging in two media. On the other hand, when the first echo conditioning unit and the second echo conditioning unit receive the first echo signal returned by the first medium, the second echo conditioning unit is cut off. When the first echo conditioning unit and the second echo conditioning unit receive the second echo signal returned by the second medium, the first echo conditioning unit outputs in saturation, realizing the self-adaptation of echo signal processing under different media.

[0103] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications once they learn the basic creative concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications falling within the scope of the present invention. Obviously, those skilled in the art can make various changes and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims

1. An ultrasonic ranging device for two media, characterized in that, It includes a microprocessor, a power amplification unit, an echo conditioning unit, and an ultrasonic transducer; The microprocessor is configured to generate a square wave pulse signal with a preset frequency according to a received ranging request and send it to the power amplification unit. The power amplification unit processes and amplifies the power of the square wave pulse signal to generate a driving signal. The ultrasonic transducer emits an ultrasonic signal to the first medium or the second medium according to the driving signal; The ultrasonic transducer receives the echo returned by the first medium and generates a first echo signal, or the echo returned by the second medium generates a second echo signal, and sends the first echo signal or the second echo signal to the echo conditioning unit. The echo conditioning unit processes the first echo signal or the second echo signal to generate a first analog signal or a second analog signal and sends it to the microprocessor. The microprocessor calculates the distance according to the first analog signal or the second analog signal; Wherein, the ultrasonic transducer is adapted to the one with a larger density among the first medium and the second medium.

2. The device according to claim 1, characterized in that, The device further includes a power supply module, and the power supply module is connected to the microprocessor, the power amplification unit, and the echo conditioning unit.

3. The device according to claim 1, characterized in that, The density of the first medium is less than the density of the second medium; The echo conditioning unit includes a first echo conditioning unit and a second echo conditioning unit. When the first echo conditioning unit and the second echo conditioning unit receive the first echo signal, the second echo conditioning unit is cut off, and the first echo conditioning unit processes the first echo signal to generate the first analog signal; when the first echo conditioning unit and the second echo conditioning unit receive the second echo signal, the first echo conditioning unit outputs saturatedly, and the second echo conditioning unit processes the second analog signal to generate the second analog signal.

4. The device according to claim 3, characterized in that, The first echo conditioning unit includes a pre-amplification module, a band-pass filtering module, a first detection module, a post-amplification module, and a first low-pass filtering module connected in sequence. The pre-amplification module is configured to perform pre-amplification on the first echo signal and send the first echo signal after pre-amplification to the band-pass filtering module. The band-pass filtering module filters out background noise from the first echo signal after pre-amplification. The first detection module is configured to perform unipolar conversion on the first echo signal output by the band-pass filtering module and send it to the post-amplification module. The post-amplification module performs further amplification processing on the received unipolar-converted first echo signal and sends it to the first low-pass filtering module. The first low-pass filtering module is configured to perform filtering processing on the received first echo signal after further amplification processing to generate the first analog signal.

5. The device according to claim 3 or 4, characterized in that, The second echo conditioning unit includes a second detection module, a proportional amplification module, and a second low-pass filtering module. The second detection module performs unipolar conversion on the second echo signal. The proportional amplification module amplifies the unipolar-converted second echo signal. The second low-pass filtering module filters the amplified second echo signal to generate the second analog signal.

6. The device according to claim 1, characterized in that, The power amplification unit includes a driving module and a boosting module. The driving module amplifies the square wave pulse signal. The boosting module is used to boost the amplified square wave pulse signal to generate the driving signal.

7. The device according to claim 1, characterized in that, The ultrasonic transducer includes a transmitter and a receiver. The transmitter emits an ultrasonic signal to the first medium or the second medium according to the driving signal. The receiver receives the first echo signal returned by the first medium or the second echo signal returned by the second medium and sends it to the echo conditioning unit. The transmitter and the receiver are integrally designed or separately designed.

8. An ultrasonic ranging system for two media, characterized in that, It includes an ultrasonic probe body and at least one set of ultrasonic ranging devices as described in any one of claims 1-7. At least one set of the ultrasonic ranging devices is distributed on the ultrasonic probe body.

9. An ultrasonic ranging method for two media using the device according to any one of claims 1-7, characterized in that, Including: The microprocessor generates a square wave pulse signal with a preset frequency according to the received ranging request and sends it to the power amplification unit. The power amplification unit processes and power-amplifies the square wave pulse signal to generate a driving signal. The ultrasonic transducer emits an ultrasonic signal to the first medium or the second medium according to the driving signal. The ultrasonic transducer receives the echo returned by the first medium and generates a first echo signal, or the echo returned by the second medium generates a second echo signal, and sends the first echo signal or the second echo signal to the echo conditioning unit. The echo conditioning unit processes the first echo signal or the second echo signal to generate a first analog signal or a second analog signal and sends it to the microprocessor. The microprocessor calculates the distance according to the first analog signal or the second analog signal. Wherein, the ultrasonic transducer is adapted to the medium with a larger density among the first medium and the second medium.

10. The method according to claim 9, wherein The density of the first medium is less than the density of the second medium. The echo conditioning unit includes a first echo conditioning unit and a second echo conditioning unit. The echo conditioning unit processes the first echo signal or the second echo signal to generate a first analog signal or a second analog signal, including: When the first echo conditioning unit and the second echo conditioning unit receive the first echo signal, the second echo conditioning unit is cut off, and the first echo conditioning unit processes the first echo signal to generate the first analog signal. When the first echo conditioning unit and the second echo conditioning unit receive the second echo signal, the first echo conditioning unit outputs in saturation, and the second echo conditioning unit processes the second analog signal to generate the second analog signal.

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