阅读说明：本技术 液态环境下溶洞勘探机器人及其控制系统、控制方法 (Karst cave exploration robot in liquid environment and control system and control method thereof ) 是由 高焕兵 鲁守银 王涛 隋首钢 高诺 于 2021-09-07 设计创作，主要内容包括：本发明液态环境下溶洞勘探机器人及其控制系统、控制方法,其中,一种液态环境下溶洞勘探机器人,包括安装支架,所述安装支架下部安装有声呐震源,底部设置有若干个与所述声呐震源连接的声呐传感器,所述声呐震源上方设置有密封电控仓,所述安装支架两侧设置有双向推进器组件,顶部设置有浮力块,所述浮力块、声呐传感器、双向螺旋推进器组件及声呐震源均与所述密封电控仓电连接并受其内的控制系统控制。其目的是为了提供一种省力省时、工作效率高且可在水下主动探测的液态环境下溶洞勘探机器人及其控制系统、控制方法。(The invention discloses a karst cave exploration robot under a liquid environment, a control system and a control method thereof, wherein the karst cave exploration robot under the liquid environment comprises a mounting support, a sonar seismic source is mounted at the lower part of the mounting support, a plurality of sonar sensors connected with the sonar seismic source are arranged at the bottom of the mounting support, a sealed electric control bin is arranged above the sonar seismic source, two-way propeller assemblies are arranged on two sides of the mounting support, a buoyancy block is arranged at the top of the mounting support, and the buoyancy block, the sonar sensors, the two-way spiral propeller assemblies and the sonar seismic source are all electrically connected with the sealed electric control bin and are controlled by the control system in the sealed electric control bin. The karst cave exploration robot is labor-saving, time-saving, high in working efficiency and capable of actively detecting underwater in a liquid environment, and the control system and the control method of the karst cave exploration robot are provided.)

1. The utility model provides a solution cavity exploration robot under liquid environment, includes installing support (6), its characterized in that, sonar seismic source (5) are installed to installing support (6) lower part, the bottom be provided with a plurality of with sonar sensor (3) that sonar seismic source (5) are connected, sonar seismic source (5) top is provided with sealed automatically controlled storehouse (2), installing support (6) both sides are provided with two-way propeller subassembly (4), and the top is provided with buoyancy piece (1), sonar sensor (3), two-way spiral propeller subassembly (4) and sonar seismic source (5) all with sealed automatically controlled storehouse (2) electricity is connected and is controlled by the control system in it.

2. A robot for exploration of caverns in liquid environment according to claim 1, characterized in that said buoyancy block (1) is internally provided with annular wings (11), said annular wings (11) being extended or retracted inside buoyancy block (1) under the control of said control system.

3. A robot for cavern exploration in liquid environment as set forth in claim 2, characterized in that said ring-shaped wing (11) comprises a semi-ring-shaped main wing (111) and two ailerons (112) articulated at both ends thereof and extending or retracting inside the main wing (111) under the control of said control system.

4. A robot for cavern exploration in liquid environment as claimed in claim 3, wherein said bidirectional auger assembly (4) comprises a first horizontal auger (41), a second horizontal auger (42), a first horizontal auger (43), and a first horizontal auger (44) for propelling in horizontal direction, which are disposed at the front and rear sides of the mounting bracket (6), and a first vertical auger (45), a second vertical auger (46) for propelling in vertical direction, which are disposed at the middle of the mounting bracket (6).

5. The robot for cavern exploration in liquid environment according to claim 4, wherein the sonar sensor (3) is connected with the sealed electric control cabin (2) through a watertight connector.

6. The control system applied to the karst cave exploration robot in the liquid environment according to any one of claims 1 to 5, is characterized by comprising:

the main processor is used for processing the sensor data and driving the motor to move through the motor driving module;

the IMU sensor is used for detecting the attitude and the speed of the robot to know whether the robot is in a horizontal state or not;

the FLASH chip is used for storing sonar data acquired by the sonar seismic source (5) and the sonar sensor (3);

the USB/WiFi dual interface is used for exporting sonar data to a computer;

the RS-485 communication module is used for communication between the robot and the ground terminal;

and the underwater proximity switch is used for detecting whether the robot collides with the wall.

7. The control system according to claim 6, wherein the ground terminal comprises a display screen and a key, the key is used for issuing a start/stop work command, and the display screen is used for displaying sonar data, robot posture and information whether to touch the wall or not in real time.

8. The control method of the control system according to claim 7, characterized by comprising the steps of:

s1, the constructor places the robot at the bottom of the pile and controls the robot to start working through a key of the ground terminal;

s2, the robot enters an autonomous data acquisition stage, the initial placement position of the robot is defined as an acquisition point A, on the acquisition point A, whether the robot is in a horizontal state or not is detected through an IMU sensor, namely whether a sonar sensor (3) is vertical to the pile bottom or not, and if not, the posture of the robot is adjusted until the robot is horizontal;

s3, emitting a sonar signal by a sonar seismic source (5), collecting return data by a sonar sensor (3), transmitting the data to a ground terminal through an RS-485 communication module, displaying the data in real time by a display screen, storing the collected data into a FLASH chip, and finishing the data collection of a collection point A;

s4, the main processor drives a motor to move through a motor driving module, then the robot is pushed to rise through a first vertical spiral propeller (45) and a second vertical spiral propeller (46) to a height I, a fixed horizontal movement direction A is defined, the robot stops after moving for 80cm along the direction A, the position is defined as a collection point B, the robot is sunk to the bottom of the pile again at the moment, a sonar sensor (3) is inserted into soil at the bottom of the pile, data collection is repeatedly carried out for one time according to the steps S2 and S3, and data collection at the collection point B is finished;

s5, the main processor pushes the robot to rise through the first vertical screw propeller (45) and the second vertical screw propeller (46) again, the robot rises to a height II, a fixed horizontal movement direction B is defined, the robot stops after moving for 80cm along the direction B, the position is defined as an acquisition point C, the robot is sunk to the pile bottom again at the moment, the sonar sensor (3) is inserted into soil at the pile bottom, data acquisition is repeatedly carried out for one time according to the steps S2 and S3, and data acquisition at the acquisition point C is finished;

s6, the main processor pushes the robot to ascend through a first vertical screw propeller (45) and a second vertical screw propeller (46), the robot rises to a height III, a fixed horizontal movement direction C is defined, the robot stops after moving for 80cm along the direction C, the position is defined as an acquisition point D, the robot is sunk to the pile bottom again at the moment, a sonar sensor (3) is inserted into soil at the pile bottom, data acquisition is repeatedly carried out for one time according to the steps S2 and S3, and data acquisition at the acquisition point D is finished;

and S7, the robot reports that the collection is finished, and the work is finished.

9. The control method according to claim 8, wherein in steps S4, S5, S6, if the robot reaches the pile wall during 80cm of movement, the movement is stopped, and the corresponding stopping points are set as acquisition point B, acquisition point C, and acquisition point D, and the acquisition is sunk.

10. The control method according to claim 9, wherein the horizontal movement direction B is a direction in which the horizontal movement direction a is rotated by 90 °, and the horizontal movement direction C is a direction in which the horizontal movement direction B is rotated by 90 °.

Technical Field

The invention relates to the technical field of underwater operation equipment, in particular to a karst cave exploration robot in a liquid environment and a control system and a control method thereof.

Background

China has a wide karst development area, particularly Guangxi, Yunnan, Guizhou, Hunan and the like, and many projects need to deal with underground karst problems. When the pile foundation is selected to treat engineering problems in a karst development area, the cast-in-situ bored pile has the advantages of no limitation of stratum change, no need of pile splicing and pile cutting, steel saving, low noise, suitability for large-scale engineering, safe construction, no ground settlement caused by water pumping and the like, thereby being widely applied. However, in the application practice of a large number of karst areas, particularly in large-diameter engineering piles, the one-pile one-hole construction investigation is difficult to judge whether the pile bottom has bad geologic bodies such as karst caves, weak interlayers and the like. In addition to construction survey, a geophysical prospecting method is also used to confirm whether a poor geologic body exists at the bottom of the pile.

At present, the commonly used geophysical prospecting methods include a seismic method, a high-density electrical method, a ground penetrating radar method and the like. Due to the small detection surface of the bottom of the pile hole, many geophysical prospecting methods cannot exert due effects in the environment. If the high-density electrical method cannot arrange a physical detection line at the bottom of a narrow pile hole. In the seismic method, the pile end is required to expose the rock surface of a fresh foundation and be leveled during detection, and a large amount of accumulated water is still in the pile hole, so that the method is difficult to implement in a drilling pile mud environment. In the ground penetrating radar method, a transmitting antenna and a receiving antenna are difficult to arrange at the bottom of a pile during detection, and if the transmitting antenna and the receiving antenna are directly arranged on the ground surface, the detection depth and the detection precision are insufficient, so that the working requirement is difficult to meet.

In view of the above, a sonar detection method for a karst cave at the bottom of a bored pile is proposed in the industry at present, which explores the application of the sonar technology to the detection of the karst cave at the bottom of the pile, and detects the development condition of the karst cave at the bottom of the pile by using slurry in a pile hole as a medium for sound wave propagation and coupling. Sonar detection refers to a method and equipment for judging the existence, position and type of an object by using underwater sound waves. In the detection of the pile bottom karst cave of the bored pile, the pile bottom karst cave is detected by sonar stress waves excited in slurry and water environment. The sonar detection method can relatively easily reach the detection standard of 3 times of pile diameter of the pile bottom and not less than 5m depth range, and the products appear on the market at present, but have the following defects in the use process:

1. the sonar detection product is heavy in weight, and constructors need to spend great strength to send the measuring instrument to the pile bottom.

2. The current measuring method is to horizontally place a measuring instrument at the bottom of a pile and collect a group of data; then, the constructor uses equipment such as a winch and the like to pull up the measuring instrument, changes the position of the pile bottom and measures again; this was repeated several times. Also, because of the heavy weight, the operation process is laborious and time-consuming, and the working efficiency is extremely low.

Disclosure of Invention

The invention aims to provide a karst cave exploration robot which is labor-saving, time-saving, high in working efficiency and capable of actively detecting underwater in a liquid environment, and a control system and a control method thereof.

In order to solve the technical problem, the application provides the following technical scheme:

the invention provides a karst cave exploration robot in a liquid environment, which comprises a mounting support, wherein a sonar earthquake source is mounted at the lower part of the mounting support, a plurality of sonar sensors connected with the sonar earthquake source are arranged at the bottom of the mounting support, a sealed electric control bin is arranged above the sonar earthquake source, two-way propeller assemblies are arranged on two sides of the mounting support, a buoyancy block is arranged at the top of the mounting support, and the buoyancy block, the sonar sensors, the two-way spiral propeller assemblies and the sonar earthquake source are all electrically connected with the sealed electric control bin and controlled by a control system in the sealed electric control bin.

The karst cave exploration robot in the liquid environment is characterized in that the buoyancy block is internally provided with an annular wing, and the annular wing extends out of or retracts into the buoyancy block under the control of the control system.

The karst cave exploration robot in the liquid environment comprises a semi-annular main wing and two ailerons which are movably connected to two ends of the main wing and extend out of or retract into the main wing under the control of the control system.

The invention relates to a karst cave exploration robot in a liquid environment, wherein a bidirectional spiral propeller assembly comprises a first horizontal spiral propeller, a second horizontal spiral propeller, a first horizontal spiral propeller and a first horizontal spiral propeller which are arranged on the front side and the rear side of an installation support and used for propelling in the horizontal direction, and a first vertical spiral propeller and a second vertical spiral propeller which are arranged in the middle of the installation support and used for propelling in the vertical direction.

According to the karst cave exploration robot in the liquid environment, the sonar sensor is connected with the sealed electric control cabin through the watertight connector.

In a second aspect, the present invention further provides a control system for a karst cave exploration robot applied to any one of the above liquid environments, including:

the main processor is used for processing the sensor data and driving the motor to move through the motor driving module;

the IMU sensor is used for detecting the attitude and the speed of the robot to know whether the robot is in a horizontal state or not;

the FLASH chip is used for storing sonar data acquired by the sonar sensor;

the USB/WiFi dual interface is used for exporting data to the computer;

the RS-485 communication module is used for communication between the robot and the ground terminal;

and the underwater proximity switch is used for detecting whether the robot collides with the wall.

The ground terminal comprises a display screen and keys, the keys are used for issuing a start/stop work command, and the display screen is used for displaying sonar data, robot postures and information whether to touch the wall or not in real time.

In a third aspect, the present invention further provides a control method based on the above control system, including the following steps:

s1, the constructor places the robot at the bottom of the pile and controls the robot to start working through a key of the ground terminal;

s2, the robot enters an autonomous data acquisition stage, the initial placement position of the robot is defined as an acquisition point A, on the acquisition point A, whether the robot is in a horizontal state or not is detected through an IMU sensor, namely whether a sonar sensor is vertical to the pile bottom or not is detected, and if the robot is not horizontal, the posture of the robot is adjusted until the robot is horizontal;

s3, emitting a sonar signal by a sonar seismic source, collecting return data by a sonar sensor, transmitting the data to a ground terminal through an RS-485 communication module, displaying the data in real time by a display screen, storing the collected data into a FLASH chip, and finishing the data collection of the collection point A;

s4, the main processor drives a motor to move through a motor driving module, and then the robot is pushed to rise through a first vertical spiral propeller and a second vertical spiral propeller to reach the height I, a fixed horizontal movement direction A is defined, the robot stops after moving for 80cm along the direction A, the position is defined as an acquisition point B, data acquisition is repeatedly carried out once by referring to the steps S2 and S3, and the data acquisition of the acquisition point B is finished;

s5, the main processor pushes the robot to ascend to a height II through the first vertical spiral propeller and the second vertical spiral propeller, a fixed horizontal movement direction B is defined, the robot stops after moving for 80cm along the direction B, the position is defined as an acquisition point C, data acquisition is repeatedly carried out once by referring to the steps S2 and S3, and data acquisition of the acquisition point C is finished;

s6, the main processor pushes the robot to ascend to a height III through the first vertical spiral propeller and the second vertical spiral propeller, a fixed horizontal movement direction C is defined, the robot stops after moving for 80cm along the direction C, the position is defined as an acquisition point D, data acquisition is repeatedly carried out once by referring to the steps S2 and S3, and data acquisition of the acquisition point D is finished;

and S7, the robot reports that the collection is finished, and the work is finished.

In the above steps S4, S5, and S6, if the robot reaches the pile wall in the process of moving 80cm, the robot stops moving, and sinks to collect the data by using the corresponding stop points as a collection point B, a collection point C, and a collection point D. The horizontal movement direction B is the direction after the horizontal movement direction A rotates for 90 degrees, and the horizontal movement direction C is the direction after the horizontal movement direction B rotates for 90 degrees.

The karst cave exploration robot and the control system and the control method thereof under the liquid environment have the following beneficial effects:

the karst cave exploration robot can move under the liquid environment under the control of the control system, the robot is provided with a sonar detection component, autonomous movement is realized under water through the cooperation of the motor and the propeller, and the data acquisition of the whole pile bottom can be completed without manual operation. The robot carrying the sonar sensor adopts a light weight design, the weight of the body is light, and the load of a propeller motor is reduced. Meanwhile, because the robot runs in a liquid environment, the buoyancy block is configured, the gravity of the robot body is overcome through the buoyancy of water, the movement of the robot can be realized by using a small driving force, time and labor are saved, the robot automatically ascends and descends to complete exploration, and the working efficiency is obviously improved. In addition, the robot of the application can also generate scouring water flow through the propeller to scour silt,

in a word, the robot has the advantages of simple structure, light dead weight, simple control system architecture, simple control method and high efficiency, realizes two functions of observing and scouring shallow silt, and greatly enhances the practicability.

The karst cave exploration robot under the liquid environment and the control system and the control method thereof are further explained with reference to the attached drawings.

Drawings

FIG. 1 is a schematic perspective view of a karst cave exploration robot in a liquid environment according to the present invention;

FIG. 2 is a front view of the karst cave exploration robot in the liquid environment;

FIG. 3 is a rear view of the karst cave exploration robot in the liquid environment;

FIG. 4 is a top view of the karst cave exploration robot in the liquid environment according to the present invention;

FIG. 5 is a bottom view of the karst cave exploration robot in the liquid environment according to the present invention;

FIG. 6 is a left side view of the karst cave exploration robot in the liquid environment according to the present invention;

FIG. 7 is a schematic structural diagram of a collapsed state of an annular wing in a karst cave exploration robot in a liquid environment according to the present invention;

FIG. 8 is a schematic structural diagram of an annular wing in a karst cave exploration robot in an unfolded state under a liquid environment according to the present invention;

FIG. 9 is a block diagram of a control system of the karst cave exploration robot in the liquid environment according to the present invention;

FIG. 10 is a flowchart of a control method of the karst cave exploration robot in the liquid environment according to the invention.

Detailed Description

As shown in fig. 1 to 6, the karst cave exploration robot in the liquid environment of the invention comprises a mounting bracket 6 as a mounting base, wherein the mounting bracket 6 is of a U-shaped upper opening structure, a sonar seismic source 5 is mounted at the lower part of the mounting bracket 6, a plurality of sonar sensors 3 are arranged on the lower surface of a bottom plate, and the sonar sensors 3 are adapted and connected with the sonar seismic source 5. A sealed electric control cabin 2 is arranged above the sonar seismic source 5, and a control system is arranged in the sealed electric control cabin 2. The left side and the right side of the mounting bracket 6 are provided with two-way propeller assemblies 4 consisting of 6 propellers. The top of the mounting bracket 6 is provided with 4 buoyancy blocks 1 with the same structure, and the buoyancy blocks 1 are made of glass beads and mainly provide positive buoyancy for the robot. The buoyancy block 1, the sonar sensor 3, the bidirectional screw propeller component 4 and the sonar seismic source 5 are all electrically connected with the sealed electric control cabin 2 and controlled by a control system in the sealed electric control cabin, and the bidirectional screw propeller component 4 and the sealed electric control cabin 2 are the whole propulsion and control core. The sonar sensor 3 is connected with the sealed electronic control cabin 2 through a watertight connector. When carrying out concrete detection operation, sonar sensor 3 can be changed by the complete set, has greatly improved the practicality.

The underwater operation robot requires to realize underwater space multi-degree-of-freedom motion, namely three translational motions (propelling, heaving and transversely moving) and three rotary motions (turning a board, pitching and transversely tilting). The motion of the robot of the application is realized by a motor propeller. Specifically, in this embodiment, the bidirectional screw assembly 4 includes 6 propellers, specifically, the left and right sides in front of the mounting bracket 6 are respectively provided with the first horizontal screw 41 and the second horizontal screw 42 for propelling along the horizontal direction, the left and right sides in rear are also respectively provided with the first horizontal screw 43 and the first horizontal screw 44 for propelling along the horizontal direction, and the 4 propellers are in charge of the horizontal direction movement of the robot under the control of the control system. The left side and the right side of the middle part of the mounting bracket 6 are provided with a first vertical screw propeller 45 and a second vertical screw propeller 46 which are used for propelling along the vertical direction, and the 2 propellers are used for the up-and-down movement of the robot.

The utility model provides six propellers of robot installation, carry out corresponding processing according to submarine silt situation:

the method comprises the following steps of: aiming at the condition that only a small amount of sludge exists, the sludge can be cleaned by using the propelling water flow of the propeller before the robot submerges to the water bottom;

the sludge amount is more, but in the cleanable range: under the condition, the robot is provided with common lighting equipment and an underwater camera, the robot is accelerated in the submerging process, four horizontal propellers are closed before contacting the water bottom, downward scouring water flow is generated completely through two vertical propellers to scour away sludge, and the sludge is transferred to other places along with the scouring water flow;

the sludge is thick and cannot be washed out: under the condition, the robot keeps a certain movement speed before contacting the water bottom, and the sonar sensor 3 contacts the hard bottom as much as possible by utilizing inertia and the thrust of the vertical propeller to complete the detection task.

The robot of this embodiment is described by taking 6 propellers as an example, and when in actual use, the number of the propellers can be flexibly increased or decreased and the installation position can be adaptively adjusted according to the exploration working condition requirement based on the inventive concept of this application, which is not listed here.

Referring to fig. 7 and 8, in order to adjust the buoyancy of the buoyancy blocks 1 in a liquid environment, an annular wing 11 is slidably embedded in each buoyancy block 1, the annular wing 11 is connected to a driving motor through a transmission mechanism, the driving motors may be four separate single motors respectively installed in the four buoyancy blocks 1, or may be a total motor installed between the four buoyancy blocks 1, and under the control of the control system, the driving motor drives the annular wing 11 to integrally extend out of or retract into the buoyancy blocks 1. The ring-shaped wing 11 comprises a semi-ring-shaped main wing 111 and two ailerons 112 movably connected at two ends thereof. The two flaps 112 are extended or retracted into the main wing 111 by the driving motor. The main wing 111 is inserted into the buoyancy block 1 radially inwards, the two ailerons 112 are installed in the main wing 111, and the size of the buoyancy force applied to the robot is adjusted by adjusting the unfolding area of the annular wing 11. Specifically, the two flaps 112 are driven by the driving motor to perform unfolding and folding actions, and the unfolding action is as follows: when the motor positively transmits, the main wing 111 extends out from the buoyancy block 1, the buoyancy is increased, the motor continuously positively transmits, the two ailerons 112 extend out from the main wing 111 and expand, and the buoyancy is further increased; retraction action: when the motor rotates reversely, the two ailerons 112 retract into the main wing 111, the buoyancy is reduced, the motor rotates reversely continuously, the main wing 111 retracts into the buoyancy block 1, and the buoyancy is further reduced.

Referring to fig. 9, the control system applied to the karst cave exploration robot in the liquid environment includes:

the main processor selects an STM32F407 high-performance ARM processor to process data of a sonar sensor 3, an IMU (inertial navigation unit) sensor, an underwater proximity switch, a water depth sensor (pressure type) and the like, and drives the driving motor of the annular wing 11 and the motors of the six propellers to move through a motor driving module;

an IMU (inertial navigation Unit) sensor for detecting the attitude (Euler angle) and speed of the robot to know whether the robot is in a horizontal state;

the large-capacity FLASH chip is used for storing sonar data acquired by the sonar sensor 3;

the USB/WiFi dual interface is used for exporting the acquired sonar data to a computer;

the RS-485 communication module is used for communication between the robot and the ground terminal; the ground terminal comprises a display screen and keys, the keys are used for issuing a start/stop work command, and the display screen is used for displaying sonar data, robot postures and information whether to touch the wall or not in real time.

The underwater proximity switch is used for detecting whether the robot collides with the wall, specifically, the moving speed of the robot is used as a comprehensive judgment condition, and under the condition of non-active stop, if the robot is detected to be static in the horizontal direction through measuring the speed, the robot may touch the pile wall and be blocked, and whether the robot collides with the wall or not is judged together by combining the obstacle distance checked by the proximity switch.

Referring to fig. 10, the control method of the karst cave exploration robot in the liquid environment based on the control system includes the following steps:

s1, the constructor places the robot at the bottom of the pile and controls the robot to start working through a key of the ground terminal;

s2, the robot enters an autonomous data acquisition stage, the initial placement position of the robot is defined as an acquisition point A, on the acquisition point A, whether the robot is in a horizontal state or not is detected through an IMU sensor, namely whether a sonar sensor 3 is vertical to the pile bottom or not is detected, and if not, the posture of the robot is adjusted to be horizontal;

s3, emitting a sonar signal by a sonar seismic source 5, collecting return data by a sonar sensor 3, transmitting the data to a ground terminal through an RS-485 communication module, displaying the data in real time by a display screen of the ground terminal, and storing the collected data into a FLASH chip; in the step, whether the data of the acquisition point A is acquired is judged, if yes, the next step is carried out; otherwise, repeating the step until the data acquisition of the acquisition point A is finished;

s4, the main processor drives the first vertical screw propeller 45 and the second vertical screw propeller 46 through the motor driving module to push the robot to ascend to the height I, for example, the robot is lifted by 30cm to have a certain vertical stroke, the sonar sensor 3 is inserted into the soil at the bottom of the pile by gravity, defining a fixed horizontal movement direction A at the height, stopping after moving 80cm along the direction A, defining the position as an acquisition point B, if the robot reaches the pile wall in the process of 80cm movement, the movement is stopped, the corresponding stopping point is taken as a collecting point B, at the moment, the robot is sunk from the collecting point B to the bottom of the pile again through a first vertical spiral propeller 45 and a second vertical spiral propeller 46, inserting the sonar sensor 3 into the soil at the pile bottom, and performing data acquisition according to the steps S2 and S3 until the data acquisition of the acquisition point B is finished;

s5, the main processor pushes the robot to rise through the first vertical screw propeller 45 and the second vertical screw propeller 46 again, the robot rises to a height II, a fixed horizontal movement direction B is defined, the direction B is the direction after the horizontal movement direction A rotates 90 degrees clockwise (or anticlockwise), the robot stops after moving 80cm along the direction B, the position is defined as an acquisition point C, if the robot reaches the pile wall in the process of moving 80cm, the movement is stopped, the corresponding stop point is used as the acquisition point C, at the moment, the robot sinks from the acquisition point C to the pile bottom through the first vertical screw propeller 45 and the second vertical screw propeller 46 again, the sonar sensor 3 is inserted into the soil at the pile bottom, and data acquisition is carried out according to the steps S2 and S3 until the data acquisition at the acquisition point C is finished;

s6, the main processor pushes the robot to ascend through a first vertical screw propeller 45 and a second vertical screw propeller 46 to a height III, a fixed horizontal movement direction C is defined, the direction C is the direction after the horizontal movement direction B rotates 90 degrees (the rotation direction is the same as that in the step S5), the robot stops after moving 80cm along the direction C, the position is defined as an acquisition point D, if the robot reaches the pile wall in the process of moving 80cm, the movement is stopped, the corresponding stop point is used as the acquisition point D, at the moment, the robot sinks to the bottom of the pile from the acquisition point D through the first vertical screw propeller 45 and the second vertical screw propeller 46 again, the sonar sensor 3 is inserted into soil at the bottom of the pile, and data acquisition is carried out according to the steps S2 and S3 until the data acquisition of the acquisition point D is finished;

and S7, the robot reports the completion of the acquisition to the console through the RS-485 communication module, and the constructor withdraws the robot to finish the work.

If the constructor considers that the data acquisition is not enough, a new round of data acquisition can be started through pressing a key, and the specific steps are referred to the steps S1-S6, which are not repeated here.

In the above steps, the lifting heights I, II and III are sufficient to make the robot have a certain vertical stroke, so that the sonar sensor 3 can be inserted into the soil at the bottom of the pile by gravity, for example, lifted by 30 cm.

In the steps, the rotation angles in the direction A, B are all 90 degrees, the collection points A, B, C, D are uniformly distributed at the pile bottom instead of being arranged at intervals, and the robot cannot touch the wall quickly, so that the accuracy of the measurement result is guaranteed.

The pile bottom karst cave sonar detection method is characterized in that sonar detection equipment is used for emitting sonar elastic waves in pile bottom slurry, when a sonar meets karst caves, corrosion cracks, weak interlayers and other bad geologic bodies in a certain range of the pile foundation bottom, sonar echoes can be generated, the echoes are received, the condition of the bad geologic bodies at the pile bottom can be analyzed according to echo characteristics, the method is an aqueous geophysical prospecting method for detecting the bad geologic bodies, can be used for detecting karst, the weak interlayers and crack zones, is reliable in evaluating the integrity of a pile foundation bearing layer of an embedded rock pile, and is an effective way for solving two problems of difficulty in detecting the karst of surrounding rocks of the pile foundation of a building and high detection cost. According to geotechnical engineering investigation standard, when a large-diameter socketed pile is adopted in a construction investigation stage, special pile foundation investigation is carried out on a pile position, investigation points are arranged pile by pile, and the exploration depth is not less than 3 times of the diameter of the pile below the pile bottom and not less than 5 m. The method for exploring the karst cave under the liquid environment by adopting the pile bottom karst cave sonar detection method has the advantages of easy explanation, high precision, obvious abnormality, strong resolving power, short construction period, less investment of instrument and equipment and low detection cost, and greatly meets the demand of karst cave exploration under the liquid environment.

The above-mentioned embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solution of the present invention by those skilled in the art should fall within the protection scope defined by the claims of the present invention without departing from the spirit of the present invention.