CN115407317B - Underwater high-frequency ultrasonic sensor, system and robot - Google Patents
Underwater high-frequency ultrasonic sensor, system and robot Download PDFInfo
- Publication number
- CN115407317B CN115407317B CN202210923453.6A CN202210923453A CN115407317B CN 115407317 B CN115407317 B CN 115407317B CN 202210923453 A CN202210923453 A CN 202210923453A CN 115407317 B CN115407317 B CN 115407317B
- Authority
- CN
- China
- Prior art keywords
- piezoelectric ceramic
- sensor
- underwater
- frequency ultrasonic
- shell
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
- G01S7/521—Constructional features
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
- G01S15/02—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems using reflection of acoustic waves
- G01S15/06—Systems determining the position data of a target
- G01S15/08—Systems for measuring distance only
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
- G01S15/88—Sonar systems specially adapted for specific applications
- G01S15/93—Sonar systems specially adapted for specific applications for anti-collision purposes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A90/00—Technologies having an indirect contribution to adaptation to climate change
- Y02A90/30—Assessment of water resources
Landscapes
- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Physics & Mathematics (AREA)
- Computer Networks & Wireless Communication (AREA)
- General Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Transducers For Ultrasonic Waves (AREA)
Abstract
The invention relates to the technical field of ultrasonic sensors, in particular to an underwater high-frequency ultrasonic sensor, an underwater high-frequency ultrasonic system and an underwater high-frequency ultrasonic robot, wherein the sensor comprises a shell (1), a piezoelectric ceramic piece (2), bonding glue (3), a backing damping layer (4) and a PCB (printed circuit board) (7), wherein the shell (1) is a concave cavity, and the concave cavity is formed by a side surface and a lower end surface; the piezoelectric ceramic piece (2), the back lining damping layer (4) and the PCB (7) are positioned in the concave cavity and are sequentially connected, the piezoelectric ceramic piece (2) is connected with the lower end face through the bonding glue (3), and the thickness of the lower bottom face of the shell (1) is between 0.6 mm and 1.2 mm. The sensor may be used for underwater distance detection.
Description
Technical Field
The invention relates to the technical field of ultrasonic sensors, in particular to an underwater high-frequency ultrasonic sensor, an underwater high-frequency ultrasonic system and an underwater high-frequency ultrasonic robot.
Background
The ultrasonic sensor emits ultrasonic signals of a certain frequency and receives echo signals, and the distance between an object causing signal reflection and the sensor is obtained by the time difference between the transmitted and received signals, so that the scheme is commonly used for foreign matter detection or distance detection in the artificial intelligence field. Generally, the higher the ultrasonic frequency sent by the sensor is, the more favorable the detection of objects at a close distance is, and the higher the sensitivity to the objects at the close distance is, the intelligent equipment can perform corresponding processing faster, so the frequency of the ultrasonic sensor is continuously increased in the industry to detect the objects at a closer distance.
However, as the frequency increases, the shorter the time for the measured object to return to the echo signal, in the limit case, the aftershock of the ultrasonic sensor itself has not yet ended, the echo signal has arrived, and the aftershock and the echo signal overlap, which may affect the accuracy of ranging. Therefore, each manufacturer considers the enhancement of the echo signal when considering the improvement of the ultrasonic frequency, and is beneficial to the accurate acquisition of the echo signal.
The prior art discloses a high-frequency sensor and a manufacturing method thereof (publication No. CN 113866772A), in the sensor, a piezoelectric ceramic plate is connected with one surface of a second matching layer, the other surface of the second matching layer is used for transmitting ultrasonic signals outwards, the sensor further comprises a vibration reduction glue layer, the vibration reduction glue layer is arranged on the outer side of the second matching layer, and an arc structure is arranged on the vibration reduction glue layer. It can be seen from the above patent that the piezoelectric ceramic plate transmits the vibration signal to the external transmission medium through the second matching layer, in order to reduce the aftershock, the echo signal of the high-frequency ultrasonic sensor is increased, and the second matching layer extends to the outside of the housing as far as possible by arranging an arc structure on the vibration-damping glue layer.
Therefore, the design direction in the field is more to make the piezoelectric ceramic plate fully contact with the transmission medium as much as possible, and the interference on the external propagation of the vibration signal of the piezoelectric ceramic plate is structurally reduced as much as possible.
However, when the high-frequency ultrasonic sensor is used for underwater ranging, a new problem is brought, the high-frequency ultrasonic sensor is a charged component, the tightness of the high-frequency ultrasonic sensor needs to be kept when the high-frequency ultrasonic sensor is used underwater, but the idea that the second matching layer on the piezoelectric ceramic plate is contacted with a transmission medium as much as possible is deviated, the high-frequency ultrasonic sensor is directly placed in a closed space, and the high-frequency ultrasonic sensor is waterproof, but simultaneously, the transmission of vibration signals of the piezoelectric ceramic plate is blocked, so that an improvement point needs to be found from the structure, and the high-frequency ultrasonic sensor can be used for underwater short-distance ranging.
Disclosure of Invention
The invention aims to provide an underwater high-frequency ultrasonic sensor, an underwater high-frequency ultrasonic system and an underwater high-frequency ultrasonic robot, which are improved in structural design of the sensor in order to maintain the performance of the sensor under the condition that a shell is required to form a closed space for the underwater application of the sensor on the basis of the prior art.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
the underwater detection high-frequency ultrasonic sensor comprises a shell 1, a piezoelectric ceramic plate 2, bonding glue 3, a backing damping layer 4 and a PCB 7, wherein the shell 1 is a concave cavity, and the concave cavity is composed of a side face 101 and a lower end face 102; the piezoelectric ceramic plate 2, the backing damping layer 4 and the PCB 7 are positioned in the concave cavity and are connected in sequence; the piezoelectric ceramic piece 2 is connected with the lower end face 102 through bonding glue 3, and the thickness of the lower end face 102 of the shell 1 is 0.6-1.2 mm.
According to the invention, aiming at an underwater application scene, the shell is designed to be of a structure with a lower end face, instead of only a side face, the piezoelectric ceramic plate 2, the backing damping layer 4 and the PCB 7 are placed in a concave cavity formed by the lower end face and the side face, the piezoelectric ceramic plate 2 is connected with the lower end face 102 through the solidified bonding glue 3, so that the piezoelectric ceramic plate 2 is tightly contacted with the lower end face 102 of the shell 1, meanwhile, the lower end face 102 of the shell 1 and the bonding glue 3 are combined to be used as a matching layer for transmitting vibration signals by the piezoelectric ceramic plate 2, and the thickness of the lower end face 102 of the shell 1 is determined to be between 0.6 and 1.2mm for a water transmission medium, so that the requirement of easy sealing of the whole sensor is met within the thickness range, and the vibration signals of the piezoelectric ceramic plate 2 can be transmitted into water through the bonding glue 3 and the lower end face 102 of the shell 1, thereby meeting the requirement of ultrasonic ranging.
As a preferable scheme, the piezoelectric ceramic plate comprises a concave cavity, a piezoelectric ceramic plate 2, a backing damping layer 4 and a PCB 7, and is characterized by further comprising pouring sealant 9, wherein the pouring sealant 9 is filled in the concave cavity, so that the piezoelectric ceramic plate 2, the backing damping layer 4 and the PCB 7 are sealed between the pouring sealant 9 and the lower end face 102. The PCB 7, the positive electrode wire 5, the negative electrode wire 6 and the lead 8 are completely wrapped by the pouring sealant 9, and gaps are not formed around the pouring sealant, so that the sensor is ensured not to have the condition of short circuit caused by water leakage in the working process, and the sensor can be ensured to work normally under the condition of large water pressure.
As a preferred scheme, the specific structure that the piezoelectric ceramic plate 2, the back lining damping layer 4 and the PCB 7 are connected in sequence is as follows: the upper surface of the piezoelectric ceramic plate 2 is connected with the back damping layer 4, and the upper surface of the back damping layer 4 is connected with the PCB 7; the piezoelectric ceramic plate 2 is connected to the PCB 7 through a positive wire 5 and a negative wire 6, and the PCB 7 supplies power to the piezoelectric ceramic plate 2 through a lead 8.
Preferably, the side surface of the piezoelectric ceramic sheet 2 is connected to the positive electrode wire 5 and the negative electrode wire 6.
In the process of sensor design, the upper surface and the lower surface of the piezoelectric ceramic piece 2 are provided with connecting ends, so that the positive wire 5 and the negative wire 6 are connected, and the piezoelectric ceramic piece 2 can be powered, but the defect brought by the design is that the connecting ends of the lower surface of the piezoelectric ceramic piece 2 are abutted against the lower end surface of the shell under the condition that the lower end surface 102 of the shell 1 exists, so that gaps exist between the lower surface of the piezoelectric ceramic piece 2 and the lower end surface 102 of the shell because of the connecting ends, and the lower surface of the piezoelectric ceramic piece 2 and the lower end surface 102 of the shell cannot be tightly attached through adhesive glue 3, so that vibration signals are affected on the external transmission of the piezoelectric ceramic piece 2. Therefore, the connection ends for connecting the positive electrode wire 5 and the negative electrode wire 6 to the piezoelectric ceramic sheet 2 are provided on the side surfaces of the piezoelectric ceramic sheet 2, and the lower surface of the piezoelectric ceramic sheet 2 and the lower end surface 102 of the housing are not affected by the adhesion of the adhesive 3.
Preferably, a projection point formed by projecting the geometric center of the piezoelectric ceramic plate 2 to the lower end surface is located at the geometric center of the lower end surface.
The projection point formed by projecting the geometric center of the piezoelectric ceramic plate 2 to the lower end face is positioned at the geometric center of the lower end face, so that the piezoelectric ceramic plate 2 and the lower end face are symmetrical in structure by the axis of the geometric center, and the control of the external transmission angle of the vibration signal is facilitated.
Preferably, the material of the housing 1 is a waterproof material with an acoustic impedance of 3-7 Mrayl.
Preferably, the material of the housing 1 is one or more of pc plastic, epoxy resin and pvc.
Preferably, the acoustic impedance of the backing damping layer 4 ranges from 2 to 10 Mrayl. For suppressing vibration of the piezoelectric ceramic and absorbing excessive vibration.
Preferably, the thickness of the backing damping layer 4 is greater than twice the wavelength of the ultrasonic signal emitted by the piezoelectric ceramic plate 2.
Preferably, the thickness of the piezoelectric ceramic sheet 2 is 0.4mm-5mm.
Based on the same conception, an obstacle avoidance sensor system is also provided, which comprises any one of the underwater high-frequency ultrasonic sensor and a control circuit,
the underwater high-frequency ultrasonic sensor transmits ultrasonic emission waves to the outside under the control of the control circuit and receives reflected waves fed back by obstacles;
the control circuit controls the system to avoid an obstacle according to the reflected wave.
As a preferable scheme, the number of the underwater high-frequency ultrasonic sensors is four, the four sensors are distributed and arranged in a front-back left-right mode, and the controller is electrically connected with the four sensors through sensor connecting wires. Four ultrasonic sensors just correspond to four positions, and can realize the omnibearing obstacle avoidance ranging detection of the obstacle avoidance sensor system.
Based on the same conception, an underwater exploration robot is also provided, which comprises the obstacle avoidance sensor system.
In conclusion, by adopting the technical scheme, the invention has the beneficial effects that:
based on the scene of high frequency ultrasonic sensor in the underwater application, the structure of high frequency ultrasonic sensor has been improved, design the shell into the structure that has the terminal surface down, and piezoceramics piece 2 through the bonding glue 3 of solidification with terminal surface connection down, combine together the terminal surface down of shell and bonding glue 3, as piezoceramics piece 2 transmission vibration signal's matching layer, to the transmission medium of water, the thickness of terminal surface is confirmed under the shell between 0.6-1.2mm, in this thickness range, the demand that sensor is whole easily airtight has been satisfied promptly, can pass through bonding glue 3 and terminal surface transmission to aquatic under the shell with piezoceramics piece 2's vibration signal again, satisfy ultrasonic ranging's demand.
Drawings
Fig. 1 is an external view of an underwater high-frequency ultrasonic sensor in embodiment 1 of the present invention;
FIG. 2 shows a design of threads on the outer side of a housing of an underwater high frequency ultrasonic sensor according to embodiment 1 of the present invention;
FIG. 3 is a cross-sectional view of an underwater high frequency ultrasonic sensor according to embodiment 2 of the present invention;
FIG. 4 is a schematic diagram of an obstacle avoidance sensor system according to embodiment 3 of the present invention;
FIG. 5 is a flowchart of an underwater detection method of an obstacle avoidance sensor system according to embodiment 3 of the present invention;
FIG. 6 is a graph showing an impedance scan of a underwater high-frequency ultrasonic sensor in an underwater detection robot according to embodiment 3 of the present invention;
fig. 7 is a line graph drawn according to the amplitude of the received signal, for example, in embodiment 3 of the present invention, where an underwater high frequency ultrasonic sensor is used in water, one sensor emits signals of different frequencies, and the other sensor receives signals.
Reference numerals: 1-shell, 101-side surface, 102-lower end surface, 2-piezoelectric ceramic plate, 3-bonding glue, 4-backing damping layer, 5-positive wire, 6-negative wire, 7-PCB board, 8-wire and 9-pouring sealant.
Detailed Description
The present invention will be described in detail with reference to the accompanying drawings.
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
Example 1
The utility model provides a high-frequency ultrasonic transducer who surveys under water, includes shell 1, piezoceramics piece 2, bonding glue 3, backing damping layer 4, anodal electric wire 5, negative pole electric wire 6, PCB board 7, wire 8, pouring sealant 9, the casing has top surface and bottom surface, and shell 1 includes side 101 (cylindricality cambered surface) and lower terminal surface 102, and side 101 and lower terminal surface 102 have constituted the spill cavity.
The positive electrode wire 5 and the negative electrode wire 6 are welded to the side connecting ends of the piezoelectric ceramic plates 2, and welding spots of the connecting ends of the ceramic plates are designed to be in a side leading-out mode so as to ensure that the surfaces of the ceramic plates are flatly attached to the lower end face of the shell.
Bonding the piezoelectric ceramic piece 2 with the positive and negative electrode wires connected to the lower end face 102 of the shell by using bonding glue 3, wherein the bonding position is in the center of the lower end face 102 of the shell; the projection of the piezoelectric ceramic plate 2 is positioned at the center of the lower end face, so that the control of the external transmission angle of the vibration signal is facilitated, and the energy conversion angle of the sensor is consistent.
The further pouring sealant 9 is filled in the concave cavity, so that the piezoelectric ceramic plate 2, the backing damping layer 4 and the PCB 7 are sealed between the pouring sealant 9 and the lower end face 102. And the semi-finished sensor finished product after the steps is encapsulated by using the pouring sealant 9, and the whole sensor is packaged into a fully-closed sensor so as to ensure that the sensor is free from water leakage and short circuit in the working process of the complex environment.
In some examples, the acoustic impedance of the backing damping layer 4 ranges between 2-10Mrayl to dampen the vibration of the piezoelectric ceramic, absorb excess vibration, and the backing damping layer 4 used is optimally thicker than twice the sensor emission wavelength.
In some examples, the backing damping layer 4 material used is one or more of silicone rubber, epoxy resin, glass beads, tungsten powder.
In some examples, the piezoelectric ceramic sheet 2 used has a thickness in the range of 0.4mm to 5mm.
In some examples, the electrode extraction mode of the piezoelectric ceramic piece 2 is flanging side extraction.
In some examples, the housing is one or more combinations of pc plastic, epoxy, pvc.
In some examples, the thickness of the combined layer formed by the lower end face of the shell 1 and the cured bonding glue is an integral multiple of 1/4 of the ultrasonic wavelength of the sensor.
In some examples, the potting adhesive 9 may be polyurethane resin, epoxy resin.
In some examples, the sensor housing side 101 is smooth and straight to facilitate removal and replacement.
In some examples, the front, middle or rear end of the side 101 outside the sensor housing 1 is externally threaded to increase the water tightness of the sensor during installation, and the housing threads may extend through the entire side 101. A sensor housing side thread design is shown in fig. 2.
Example 2
As can be seen in fig. 1 and 3, an underwater high-frequency ultrasonic sensor comprises a housing 1, a piezoelectric ceramic plate 2, bonding glue 3, a backing damping layer 4, a positive electrode wire 5, a negative electrode wire 6, a PCB board 7, a wire 8 and a potting adhesive 9. The piezoelectric ceramic plate 2 is connected to the lower end face 102 of the shell 1 through the positive wire 5 and the negative wire 6 in a welding mode, the piezoelectric ceramic plate 2 is connected to the lower end face 102 of the shell 1 through the solidified bonding glue 3, the backing damping layer 4 is encapsulated to the upper surface of the piezoelectric ceramic plate 2 after the bonding glue 3 is solidified, the positive wire 5 and the negative wire 6 led out by the piezoelectric ceramic plate 2 are connected to one surface of the PCB 7, the lead wire 8 is connected to one surface of the PCB, the encapsulating glue 9 is encapsulated in the shell 1 after the steps are completed, and the upper surface of the encapsulating glue exceeds the PCB 7 after encapsulation.
In some examples, the acoustic impedance of the backing damping layer 4 ranges from 2 to 10Mrayl, and is used to suppress the vibration of the piezoelectric ceramic plate 2 and absorb the excessive vibration thereof, so that the sensor outputs different impedance curves, and the regularity of the sensor transmitting and receiving signals and the signal strength are improved.
In some examples, the combined layer of the bonding glue 3 and the lower end face 102 of the housing has a thickness of 0.6-1.2mm, because the root cause affecting the sensitivity and bandwidth of the underwater sensor is that the acoustic impedances of the piezoelectric ceramic material of the transducer and water are seriously mismatched, the acoustic impedances are Zc10-35Mrayl, zw=1.5 Mrayl respectively, and the matching layer between the piezoelectric ceramic sheet and the transmission medium is generally 1/4 of the sensor wavelength thick when the acoustic impedance of the housing is usedThe transmission coefficient of sound wave is the largest, 1/4 of the emission wavelength of the sensor is taken as the thickness of the lower end face 102 of the shell 1, the thickness is the best, Z C 、Z W The acoustic impedance of the piezoelectric ceramic plate 2 and the acoustic impedance of water are respectively, the thickness of the shell is mainly influenced by the frequency of the sensor ceramic plate and the acoustic impedance of a propagation medium, and the optimal thickness of a combined layer formed by the bonding glue 3 for the underwater high-frequency ultrasonic sensor and the lower end face 102 of the shell is between 0.6 and 1.2 mm. As can be seen from the sectional view 3, the piezoelectric ceramic plate 2 is completely wrapped by the backing damping layer 4, the bonding glue 3 and the housing 1, and the lower end surface 102 of the housing 1 is tightly attached to the piezoelectric ceramic plate 2 through the bonding glue 3, so that the housing 1 has a matching layer function and good transmission capability in an underwater environment.
After the structure is connected, the concave cavity of the shell 1 is filled with the pouring sealant 9, so that the sensor can work normally under the condition of large water pressure, the pouring sealant 9 completely wraps the PCB 7, the positive electrode wire 5, the negative electrode wire 6 and the lead 8, and the situation that the short circuit and water leakage are caused by water leakage in the working process is avoided.
Example 3
A schematic diagram of a structure of the obstacle avoidance sensor system is shown in fig. 4, a sensor is installed at a test position, the ultrasonic detection technology is adopted through alternate emission and reception of an ultrasonic sensor, and the distance between the sensor and an obstacle can be calculated by measuring the time difference between emission and reception of a periodic signal of ultrasonic and measuring the temperature and density of a liquid medium.
The higher the frequency of the sensor is, the smaller the angle detected in water is, the higher the precision is, the lower the frequency of the sensor is, the larger the detection angle in water is, the lower the precision is, and the control angle and the precision can be achieved by changing the thickness, the diameter and the shape of the piezoelectric ceramic plate 2, so that the underwater sensor is suitable for underwater sensors with different working environments and different requirements.
The piezoelectric ceramic plate used in the underwater high-frequency ultrasonic sensor has a thickness ranging from 0.4mm to 5mm, and in some examples, when the piezoelectric ceramic plate 2 has a diameter of 17mm and a thickness of 4mm, the sensor detection angle at-6 db can be measured to be 10.2 degrees when purified water is used as a propagation medium at normal temperature and pressure, and the minimum detection precision is 1.5mm in a driving mode of the sensor using an integrated transceiver.
The lead 8 can be a common twisted pair, and coaxial cables or shielding wires can be used for replacing the lead in order to improve the anti-interference capability of the sensor in water, so as to ensure the accuracy of the sensor in a complex underwater environment.
In some examples, a very thin layer of anti-corrosion material may be applied to the surface of the sensor housing 1 to ensure that the sensor does not experience abrupt changes in performance due to corrosion of the housing 1 during long-term operation under water, thereby improving the reliability thereof.
The obstacle avoidance sensor system shown in fig. 4 comprises an underwater high-frequency ultrasonic sensor and a control circuit, wherein the underwater high-frequency ultrasonic sensor is controlled by the control circuit to emit ultrasonic emission waves to the outside and receive reflected waves fed back by obstacles; the control circuit controls the system to avoid the obstacle according to the reflected wave. The underwater high-frequency ultrasonic sensor is characterized in that four high-frequency ultrasonic sensors are arranged oppositely, and the controller is electrically connected with the four sensors through sensor connecting wires. Four ultrasonic sensors just correspond to four positions, and can realize the omnibearing obstacle avoidance ranging detection of the obstacle avoidance sensor system. A flow chart of an underwater detection method of the obstacle avoidance sensor system is shown in fig. 5.
In some examples, in the practical application process, the four-direction obstacle avoidance sensor system composed of four sensors and a control circuit, because the sensor detection mode is a transceiver unit (the same sensor sends out ultrasonic signals and then receives reflected signals fed back by obstacles as a transceiver unit), the sensor detection precision is affected by the aftershock of the sensor, the aftershock T range is 10um-300um, and the sound velocity V of water at normal temperature and normal pressure w =1500 m/s. Can obtain the blind area range D=V affected by the aftershock W T/2, between 7.5 and 225mm, and the magnitude of the aftershock is in direct proportion to the magnitude of the voltage driving the ceramic plate, the larger the voltage is, the larger the aftershock is, and the lower the aftershock isThe lower the shock.
In some examples, the driving voltage used by the sensor can range from 1v to 1/2 of the compressive strength of the ceramic plate, and the driving voltage ranges from 1v to 2000v with a millimeter thick ceramic plate with 4000v/mm compressive strength, but with the increase of the driving voltage and the increase of the detection distance, the aftershock is increased to increase the detection blind area. While the sensor detection accuracy is also related to the scanning accuracy of the sensor receiving circuit.
FIG. 6 is an impedance sweep curve of a high frequency ultrasonic sensor in a water under an underwater detection robot; from the figure, it can be seen that the actual resonance frequency point of the transmitting signal of the sensor is 485kHz, and the antiresonance frequency point is 555kHz. FIG. 7 is a line graph of a signal received by one sensor and plotted according to the amplitude of the received signal, using an underwater high frequency ultrasonic sensor of the present invention in water. When a test mode that one sensor emits and one sensor receives is used, along with the change of the driving frequency (abscissa) of the emitting sensor, the amplitude of a signal received by the receiving sensor also changes correspondingly, the strongest part of the signal is just positioned near the anti-resonance frequency 555k of the sensor, the basic rule of the ultrasonic sensor correlation test is met, and the stronger the emitting driving frequency is when the emitting driving frequency is close to the anti-resonance frequency of the receiving sensor.
Compared with an underwater sensor using a plurality of matching layers and a shell, the sensor has the advantages that the depth of underwater detection is deeper through a fully-closed process, the reliability of the sensor is higher, and the manufacturing, maintenance and replacement costs are lower, so that the sensor is suitable for large-scale use.
The obstacle avoidance sensor system shown in fig. 4 is installed in the structure of the underwater robot, and can be installed around the underwater robot to improve the autonomous recognition or obstacle avoidance function of the robot, and the detection capability of the robot can be further improved by adopting an array installation mode.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.
Claims (11)
1. An underwater detection high-frequency ultrasonic sensor comprises a shell (1), a piezoelectric ceramic piece (2), bonding glue (3), a back lining damping layer (4) and a PCB (7), and is characterized in that,
the shell (1) is a concave cavity, and the concave cavity is composed of a side face (101) and a lower end face (102);
the piezoelectric ceramic sheet (2), the backing damping layer (4) and the PCB (7) are positioned in the concave cavity and are connected in sequence; the piezoelectric ceramic piece (2) is connected with the lower end face (102) through bonding glue (3), and the thickness of the lower end face (102) of the shell (1) is between 0.6 and 1.2mm, so that the shell (1) has the matching layer function and good transmission capacity in an underwater environment;
welding an anode wire (5) and a cathode wire (6) to the side connecting end of the piezoelectric ceramic plate (2), and designing welding spots of the connecting end of the piezoelectric ceramic plate (2) into a side leading-out mode so as to ensure that the surface of the piezoelectric ceramic plate (2) is flatly attached to the lower end face (102) of the shell (1);
the thickness of a combined layer formed by the lower end face of the shell (1) and the solidified bonding glue is an integral multiple of 1/4 of the ultrasonic wavelength of the sensor;
the shell (1) is made of waterproof materials with acoustic impedance of 3-7 Mrayl.
2. An underwater high frequency ultrasonic sensor as claimed in claim 1, further comprising a pouring sealant (9), wherein the pouring sealant (9) is filled in the concave cavity, so that the piezoelectric ceramic plate (2), the backing damping layer (4) and the PCB board (7) are sealed between the pouring sealant (9) and the lower end face.
3. The underwater high-frequency ultrasonic sensor according to claim 1, wherein the specific structure of the piezoelectric ceramic plate (2), the backing damping layer (4) and the PCB board (7) which are sequentially connected is as follows:
the upper surface of the piezoelectric ceramic piece (2) is connected with the back lining damping layer (4), and the upper surface of the back lining damping layer (4) is connected with the PCB (7); the piezoelectric ceramic piece (2) is connected to the PCB (7) through an anode wire (5) and a cathode wire (6), and the PCB (7) supplies power to the piezoelectric ceramic piece (2) through a lead (8).
4. An underwater detection high-frequency ultrasonic sensor as claimed in claim 1, characterized in that a projection point formed by projecting the geometric center of the piezoelectric ceramic plate (2) to the lower end face is located at the geometric center of the lower end face.
5. An underwater detection high frequency ultrasonic sensor as claimed in claim 1, wherein the material of the housing (1) is one or more of pc plastic, epoxy resin and pvc.
6. An underwater high frequency ultrasonic sensor as claimed in claim 1, characterised in that the acoustic impedance of the backing damping layer (4) is in the range 2-10 Mrayl.
7. An underwater detection high frequency ultrasonic sensor as claimed in claim 6, characterized in that the thickness of the backing damping layer (4) is greater than twice the wavelength of the ultrasonic signal emitted by the piezoelectric ceramic plate (2).
8. An underwater high frequency ultrasonic sensor as claimed in any one of claims 1 to 7, characterised in that the piezoelectric ceramic plate (2) has a thickness of 0.4mm to 5mm.
9. An obstacle avoidance sensor system comprising an underwater high frequency ultrasonic sensor and control circuitry as claimed in any one of claims 1 to 8,
the underwater high-frequency ultrasonic sensor transmits ultrasonic emission waves to the outside under the control of the control circuit and receives reflected waves fed back by obstacles;
the control circuit controls the system to avoid an obstacle according to the reflected wave.
10. The obstacle avoidance sensor system of claim 9 wherein the plurality of underwater high frequency ultrasonic transducers is four, the four transducers being disposed in a back-to-forth, side-to-side arrangement, and the controller being electrically connected to the four transducers by transducer connection lines.
11. An underwater detection robot comprising an obstacle avoidance sensor system as claimed in any one of claims 9 or 10.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210923453.6A CN115407317B (en) | 2022-08-02 | 2022-08-02 | Underwater high-frequency ultrasonic sensor, system and robot |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210923453.6A CN115407317B (en) | 2022-08-02 | 2022-08-02 | Underwater high-frequency ultrasonic sensor, system and robot |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115407317A CN115407317A (en) | 2022-11-29 |
| CN115407317B true CN115407317B (en) | 2023-09-29 |
Family
ID=84158928
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210923453.6A Active CN115407317B (en) | 2022-08-02 | 2022-08-02 | Underwater high-frequency ultrasonic sensor, system and robot |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115407317B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2517155A1 (en) * | 1981-11-25 | 1983-05-27 | Metraflu | Hydrophonic appts. for acoustic wave detection in liq. - has tubular piezoelectric pressure pick=up in watertight sheath |
| CN201611266U (en) * | 2010-03-16 | 2010-10-20 | 山东力创科技有限公司 | Ultrasonic transducer of heat meter |
| CN106370731A (en) * | 2016-09-09 | 2017-02-01 | 中国石油大学(华东) | Ultrasonic longitudinal and shear wave-resistivity integrated type probe for rock physical experiment |
| CN107990924A (en) * | 2017-12-07 | 2018-05-04 | 广东奥迪威传感科技股份有限公司 | A kind of ultrasonic sensor |
| CN113866772A (en) * | 2021-11-02 | 2021-12-31 | 成都汇通西电电子有限公司 | High-frequency sensor and manufacturing method thereof |
| CN114111928A (en) * | 2021-11-23 | 2022-03-01 | 成都汇通西电电子有限公司 | High-frequency ultrasonic sensor suitable for gas flow detection |
| CN114111927A (en) * | 2021-11-23 | 2022-03-01 | 成都汇通西电电子有限公司 | High-frequency ultrasonic sensor suitable for gas flow detection |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20130023602A (en) * | 2011-08-29 | 2013-03-08 | 삼성전기주식회사 | Ultrasonic waves sensor |
-
2022
- 2022-08-02 CN CN202210923453.6A patent/CN115407317B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2517155A1 (en) * | 1981-11-25 | 1983-05-27 | Metraflu | Hydrophonic appts. for acoustic wave detection in liq. - has tubular piezoelectric pressure pick=up in watertight sheath |
| CN201611266U (en) * | 2010-03-16 | 2010-10-20 | 山东力创科技有限公司 | Ultrasonic transducer of heat meter |
| CN106370731A (en) * | 2016-09-09 | 2017-02-01 | 中国石油大学(华东) | Ultrasonic longitudinal and shear wave-resistivity integrated type probe for rock physical experiment |
| CN107990924A (en) * | 2017-12-07 | 2018-05-04 | 广东奥迪威传感科技股份有限公司 | A kind of ultrasonic sensor |
| CN113866772A (en) * | 2021-11-02 | 2021-12-31 | 成都汇通西电电子有限公司 | High-frequency sensor and manufacturing method thereof |
| CN114111928A (en) * | 2021-11-23 | 2022-03-01 | 成都汇通西电电子有限公司 | High-frequency ultrasonic sensor suitable for gas flow detection |
| CN114111927A (en) * | 2021-11-23 | 2022-03-01 | 成都汇通西电电子有限公司 | High-frequency ultrasonic sensor suitable for gas flow detection |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115407317A (en) | 2022-11-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN201611266U (en) | Ultrasonic transducer of heat meter | |
| US4610164A (en) | Method of detecting liquid level | |
| CN114111928B (en) | High-frequency ultrasonic sensor suitable for gas flow detection | |
| CN115407317B (en) | Underwater high-frequency ultrasonic sensor, system and robot | |
| CN114111927B (en) | High-frequency ultrasonic sensor suitable for gas flow detection | |
| CN201589860U (en) | High frequency wideband underwater sound projector with low transient response | |
| CN113866772A (en) | High-frequency sensor and manufacturing method thereof | |
| CA2257584C (en) | Acoustic transducer system | |
| CN109604133B (en) | Low-directivity fluctuating arc transmitting transducer array | |
| CN112666262A (en) | Ultrasonic detection probe for ultrasonic nondestructive detection of laser welding seam of lithium battery shell | |
| CN110475621A (en) | Be integrated in can piezoelectric ceramic transducer element in vibrating diaphragm sonic transducer | |
| CN113359119B (en) | Side-scanning transducer based on circular arc piezoelectric composite material and preparation method thereof | |
| CN115825963B (en) | Ultrasonic sensor | |
| CN217133367U (en) | High-frequency sensor | |
| CN212807172U (en) | Transducer and supersound water gauge | |
| CN205506203U (en) | High pressure resistant spherical hydrophone | |
| CN110523608B (en) | Integrated double-frequency transducer | |
| JP2001258097A (en) | Ultrasonic wave transducer and its manufacturing method | |
| CN112153543B (en) | Half-space radiation high-frequency broadband transducer | |
| CN220873252U (en) | Multi-type functional material combined weak directivity spherical shell transducer | |
| CN110441759A (en) | A kind of Ulerasonic senser casing structure and ultrasonic sensor | |
| CN219085142U (en) | High-frequency sensor suitable for sweeping robot | |
| CN220479324U (en) | Piezoelectric ceramic piece and ultrasonic water meter transducer | |
| CN111464915B (en) | Novel receiving and transmitting combined elliptical ring transducer | |
| CN218251310U (en) | High-temperature and high-pressure resistant transducer with ceramic particles spliced into array |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |