CN105158431A - Unmanned pollutant tracing system and method - Google Patents

Abstract

The invention discloses an unmanned pollutant traceability system and a traceability method thereof. It includes an unmanned pollutant traceability ship, a handheld remote control and a remote monitoring base station. The unmanned pollutant traceability ship communicates with the remote monitoring base station through GPRS, and the unmanned pollutant traceability ship communicates wirelessly with the handheld remote control through radio frequency communication. The present invention uses an embedded microcomputer system, a pollutant concentration detection device, a position and posture sensor, a GPS module, etc. to realize the function of searching for fixed sewage outlets in polluted watersheds, and to improve the speed of locating pollution sources after the sneaky discharge time of the factory occurs, and saves Manpower and capital investment; the system with the embedded system as the core and the three-dimensional sampling device can also achieve fixed-point and fixed-depth sampling, which also facilitates the sampling of polluted water bodies. Departments have a basis for the punishment of polluting enterprises.

Description

An unmanned pollutant traceability system and its traceability method

technical field

The invention relates to the field of pollutant traceability, in particular to an unmanned pollutant traceability system and a traceability method thereof.

Background technique

Water is the blood of the ecosystem, and sufficient and high-quality water resources are the material basis for the healthy development of the ecosystem. my country is a resource-based water-scarce country. According to statistics, in the first half of 2013, 69.3% of the water quality sections in my country’s top ten river basins met Grade I-III standards, 19.9% met Grade IV-V grades, and 10.8% fell below Grade V grades. More than 30% of the country's important watersheds are polluted to varying degrees. The most prominent aspect of this situation is that industrial sewage discharge has not been standardized and rationalized, and the phenomenon of illegal discharge by enterprises is relatively serious. In order to improve the effectiveness of the treatment of illegal emissions by enterprises, on the one hand, it is necessary to strengthen the linkage and crackdown of local environmental supervision, administrative law enforcement, and criminal justice; Then find out the root cause, obtain evidence, and implement responsibility in a timely manner. However, the smuggling outlets of corporate pollution are often very hidden. After the pollution problem is discovered, the relevant departments usually need to spend a lot of time to determine the source of the pollution, which delays the best time for treatment; sometimes they even give up investigating the responsible unit because they cannot confirm the location of the source.

In the Chinese invention patent with the application number of 201410216892.9, the mobile water pollution data collection system can monitor the water quality change trend of the river basin, and only a small amount of the device is required to detect water pollution indicators in the river basin, but the system only collects water quality data of the river And the function of visualizing the water quality of the river basin on the GIS platform does not have the function of traceability of pollutants, and cannot automatically track and locate pollution sources. In the Chinese invention patent with application number 201410390303.9, the drone-based industrial water pollution source detection method can conduct image monitoring and sampling checks on enterprise drainage through drones, and complete the analysis of the impact of enterprises on water bodies , but when the pollutants do not cause the color change of the water body, the content of the invention cannot meet the requirements of pollutant tracking and positioning.

Aiming at enterprises with high pollution load and large room for improvement and remediation, design and develop a mobile unmanned pollutant traceability system, which can search for fixed sewage outlets in polluted watersheds, and remediate polluted watersheds and surrounding environments for relevant departments Provide strong help; at the same time, it can flexibly respond to sudden pollution accidents, quickly track the spread of pollution sources, and assist in emergency management of accidents.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art, and provide an unmanned pollutant traceability system and a traceability method thereof.

An unmanned pollutant traceability system includes an unmanned pollutant traceability ship, a hand-held remote control and a remote monitoring base station. The unmanned pollutant traceability ship communicates with the remote monitoring base station through GPRS, and the unmanned pollutant traceability ship communicates with the Wireless communication with handheld remote control; the unmanned pollutant traceability ship includes a hull, a main control unit, a water sampling device and an online water quality detection device. The hull is composed of a hull shell, a power unit and a power module. The main control unit is composed of a main control chip, a GPRS module, a RF wireless module, a GPS module, an electronic compass, a steering gear drive DC motor drive, a stepper motor drive and a JTAG interface, wherein the GPRS module, RF wireless module, The GPS module is connected to the main control chip with an RS232 interface, and the electronic compass is connected to the main control chip using an I ² C interface; the water body sampling device is composed of a lifting device, a sampling device and a flow distribution device, and the lifting device is composed of a sampling hose, a step The inlet motor, reel, and transmission device are composed, the sampling device is composed of a peristaltic pump, a two-way joint, and the diversion device is composed of a steering gear, a diverter plate and a water tank. The water quality online detection device is mainly composed of an immersion probe and a signal acquisition circuit. The online detection device is connected to the main control unit through the RS485 interface, and the detection information is transmitted to the main control unit; the handheld remote control is composed of the main control chip, RF wireless Module, programmable rocker, programmable keys, LCD display, RS232 interface circuit, JTAG interface and power supply module, the RF wireless module is connected to the main control chip through the RS232 interface circuit, programmable rocker, programmable keys, The LCD screens are all connected with the main control chip. The remote monitoring base station can be composed of an ordinary PC with a fixed external network IP and monitoring center software.

The steps of an unmanned pollutant traceability method are as follows:

1) Startup: After the unmanned pollutant traceability ship is started, when the user knows the approximate location of the pollution zone, he can quickly reach the pollution zone through manual control or autonomous navigation, narrow the search range, and speed up the progress of pollution source location. If the user does not know Where the pollution source is located, the unmanned source tracing ship will advance several meters against the current or obliquely against the current, which will be used as the starting point for the traceability of pollutants;

2) Pollution zone search: If no pollutants are found after the initial step length after the unmanned pollutant traceability ship starts, the unmanned pollutant tracer ship will search the entire river section upstream until no one pollutes. The on-line detection device carried by the material traceability ship detects pollutants, and then enters the "pollution source tracking" mode;

3) Pollution source tracking: the unmanned pollutant traceability ship uses the historical pollutant concentration data, historical direction data, historical step data and current pollutant concentration data stored in the main control chip to formulate the current direction strategy and step strategy, If the tracking process does not deviate from the pollution zone, the current pollutant concentration, direction and step data detected by the online detection device are stored in the main control chip, become historical data, and enter the next pollutant tracking cycle. If it deviates from the pollution zone, then Enter the "pollution zone deviation" mode;

4) Pollution zone deviation: to prevent the divergence of the tracking path. After entering this mode, the unmanned pollutant traceability ship must first confirm the pollution source. If the conditions are not met, the pollution zone will be searched again, and the "pollution source tracking" mode will be entered again;

5) Pollution source confirmation: Use the pollutant concentration value, the concentration change rate value, and the distance threshold between the point where the pollutant was last detected before departing from the pollution zone as the basis for confirming the pollution source, and judge whether the location is a pollution source. Pollution zone search", if it is a pollution source, the coordinates of the position located by GPS will be sent to the remote monitoring center, and the traceability process of pollutants is over.

The described step 1) is: there are two control modes for starting, namely: manual remote control and autonomous navigation two motion control modes, the two control modes can be switched by the hand automatic switch button on the handheld remote control, and in the manual mode , the unmanned pollutant traceability ship will conduct regular communication checks. If it is found that the control signal has not been received for a long time, the unmanned pollutant traceability ship will switch to the autonomous navigation mode, and will follow the previously recorded driving conditions in the main control module Flash. The coordinates of the passing points of the trajectory, and return to the water area where the signal of the handheld remote control can be received. The GPS positioning method used in the autonomous navigation motion control mode, in order to improve the accuracy of GPS positioning, also has innovations in the positioning algorithm: using the differential GPS positioning method, the GPS positioning data after the difference reduces the risk caused by solar activities, weather changes, and surrounding areas. Public errors caused by environmental impacts, etc.

The present invention uses an embedded microcomputer system and a pollutant concentration detection device, a position and posture sensor, a GPS module, etc. to realize the function of searching for fixed sewage outlets in polluted watersheds, in order to improve the speed of pollution source positioning after the sneaky discharge time of the factory occurs, and save It saves manpower and capital investment; the system with the embedded system as the core and the three-dimensional sampling device can also achieve fixed-point and fixed-depth sampling, which also facilitates the sampling of polluted water bodies, so that the water samples of the post-water quality analysis department have a source, and also enable Government departments have a basis for punishing polluting enterprises.

Description of drawings

Figure 1 is a structural block diagram of the unmanned pollutant traceability system;

Fig. 2 is the circuit schematic diagram of the main control unit of the present invention;

Fig. 3 is a schematic diagram of a three-dimensional sampling device of the present invention;

Fig. 4 is a schematic diagram of the handheld remote controller of the present invention;

Fig. 5 is a schematic diagram of the monitoring center software of the remote monitoring base station of the present invention;

Fig. 6 is a work flow diagram of the pollution source traceability method of the present invention;

Fig. 7 is a flow chart of starting steps in the pollution source traceability method;

Fig. 8 is a flow chart of pollution source tracking in the pollution source traceability method.

Detailed ways

As shown in Figures 1 and 2, an unmanned pollutant traceability system includes an unmanned pollutant traceability ship 7, a handheld remote control 5, and a remote monitoring base station 6. The unmanned pollutant traceability ship 7 communicates with the remote monitoring base station 6 through GPRS The unmanned pollutant traceability ship 7 wirelessly communicates with the hand-held remote controller 5 through radio frequency communication; the unmanned pollutant traceability ship includes a hull 4, a main control unit 1, a water body sampling device 2 and an online water quality detection device 3, the The hull 4 is composed of a hull shell, a power unit and a power supply module, and adopts a catamaran type. The main control unit 1 is driven by a main control chip, a GPRS module, a RF wireless module, a GPS module, an electronic compass, and a steering gear drive DC motor. , a stepping motor drive and a JTAG interface, wherein the GPRS module, the RF wireless module, and the GPS module are connected to the main control chip with an RS232 interface, and the electronic compass is connected to the main control chip using an I ² C interface; the water body The sampling device 2 is composed of a lifting device, a sampling device and a flow distribution device. The lifting device is composed of a sampling hose, a stepping motor, a reel, and a transmission device. The sampling device is composed of a peristaltic pump and a two-way joint. The water quality online detection device 3 is mainly composed of a submerged probe and a signal acquisition circuit. The online detection device 3 is connected with the main control unit 1 through the RS485 interface, and the detection information is transmitted to the main control unit 1; the handheld The remote controller is composed of a main control chip, an RF wireless module, a programmable rocker, a programmable button, a liquid crystal display, an RS232 interface circuit, a JTAG interface and a power supply module. The RF wireless module is connected to the main control chip through the RS232 interface circuit. The programmable rocker, programmable keys, and LCD display are all connected to the main control chip. The remote monitoring base station can be composed of an ordinary PC with a fixed external network IP and monitoring center software.

The main control chip is implemented by a STM32F103RBT6P single-chip microcomputer of STMicroelectronics (ST), which has the advantages of small size, fast calculation speed, good modular performance, and high reliability. The sensor data reading processing analysis program, wireless communication, various driver programs, and the control program of the autonomous navigation of the unmanned pollutant traceability ship and the pollutant traceability method program are all stored in the Flash of the main control chip, which is responsible for setting the basic parameters. Functions such as setting, controlling the program flow and performing regular communication with each module and unit. The GPRS module, the RF wireless module, and the GPS module are connected to the main control chip by an RS232 interface, the electronic compass is connected to the main control chip by an I ² C interface, the water quality sensor is connected to the main control unit by an RS485 communication interface, and the motor drives The module is connected with the main control unit through the PWM wave signal conversion circuit. The electronic compass is connected with the main control chip through the I ² C interface.

Figure 3 shows the water sample collection device of the unmanned pollutant traceability ship. The key to water sampling is the ability to collect water samples at different depths and store them in corresponding water tanks. The unmanned pollutant traceability ship is equipped with three water tanks , each with a capacity of 4L, that is, a trip can take up to three water samples. The device consists of three parts: a lifting device, a sampling device and a diversion device. The lifting device includes a sampling hose, a stepping motor, a reel and a transmission device. , diverter plate and water tank. Its working principle is that the reel drives the inlet end of the sampling hose up and down, and at the same time ensures that the outlet end of the reel is fixed, connects the peristaltic pump, and stores different water samples into the corresponding water tank through the diverter plate. The specific implementation is that the water inlet end of the sampling hose is covered with a filter screen and a 250g weight is immersed in the water area to be tested, and wound on the reel. The entire reel rotates under the action of the stepping motor and the transmission device to realize the lifting of the water end of the sampling hose. After the peristaltic pump discharges water, it is connected to the two-way joint, which rotates under the action of the steering gear, and the water samples are introduced into different drainage grooves of the diverter plate, and injected into the corresponding water tanks.

As shown in Figure 4, the handheld remote controller is composed of a main control chip, RF wireless module, programmable joystick, programmable buttons, liquid crystal display, RS232 interface circuit, JTAG interface and power supply module; The circuit is connected with the main control chip, the programmable rocker, the programmable buttons, and the LCD display are all connected with the main control chip, and the power supply module supplies power for each module.

The remote monitoring base station can be composed of an ordinary PC with a fixed external network IP and monitoring center software. The monitoring center software is shown in Figure 5. It is mainly composed of five parts: menu bar, map, parameter configuration, working status, and real-time monitoring data. The API implementation of Baidu Map is used.

As shown in Figure 5, the steps of an unmanned pollutant traceability method are as follows:

1) Startup: After the unmanned pollutant traceability ship is started, when the user knows the approximate location of the pollution zone, he can quickly reach the pollution zone through manual control or autonomous navigation, narrow the search range, and speed up the progress of pollution source location. If the user does not know Where the pollution source is located, the unmanned source tracing ship will advance several meters against the current or obliquely against the current, which will be used as the starting point for the traceability of pollutants;

2) Pollution zone search: If no pollutants are found after the initial step length after the unmanned pollutant traceability ship starts, the unmanned pollutant tracer ship will search the entire river section upstream until no one pollutes. The on-line detection device carried by the material traceability ship detects pollutants, and then enters the "pollution source tracking" mode;

3) Pollution source tracking: the unmanned pollutant traceability ship uses the historical pollutant concentration data, historical direction data, historical step data and current pollutant concentration data stored in the main control chip to formulate the current direction strategy and step strategy, If the tracking process does not deviate from the pollution zone, the current pollutant concentration, direction and step data detected by the online detection device are stored in the main control chip, become historical data, and enter the next pollutant tracking cycle. If it deviates from the pollution zone, then Enter the "pollution zone deviation" mode;

4) Pollution zone deviation: to prevent the divergence of the tracking path. After entering this mode, the unmanned pollutant traceability ship must first confirm the pollution source. If the conditions are not met, the pollution zone will be searched again, and the "pollution source tracking" mode will be entered again;

5) Pollution source confirmation: Use the pollutant concentration value, the concentration change rate value, and the distance threshold between the point where the pollutant was last detected before departing from the pollution zone as the basis for confirming the pollution source, and judge whether the location is a pollution source. Pollution zone search", if it is a pollution source, the coordinates of the position located by GPS will be sent to the remote monitoring center, and the traceability process of pollutants is over.

Described step 1) is: start has two kinds of control modes, namely: two kinds of motion control modes of manual remote control and self-navigation, two kinds of control modes can be switched by hand-held automatic switching button on the remote control 5, and in manual mode At the same time, the unmanned pollutant traceability ship 7 will perform regular communication checks. If it is found that the control signal has not been received for a long time, the unmanned pollutant tracer ship will switch to the autonomous navigation mode, and it will The passing point coordinates of the track of travel return to the water area where the hand-held remote controller 5 signal can be received. The GPS positioning method used in the autonomous navigation motion control mode, in order to improve the accuracy of GPS positioning, also has innovations in the positioning algorithm: using the differential GPS positioning method, the GPS positioning data after the difference reduces the risk caused by solar activities, weather changes, and surrounding areas. Public errors caused by environmental impacts, etc.

Example:

Step 1) of the above-mentioned unmanned traceability method for pollutants starts, and there are two control schemes: (1) the user knows the approximate location of the pollution source, and can send the destination latitude and longitude coordinates to the unmanned traceability ship through the monitoring center, and the unmanned traceability ship Perform autonomous navigation to the destination, and then start the steps of tracking and locating pollution sources. (2) The user also manually remote-controls the unmanned source-tracing ship through the handheld terminal to the destination. This can save the time of searching for the pollution zone and speed up the process of tracking and locating pollutants. The specific workflow is shown in Figure 7, and the meaning of each specific step is as follows:

① The unmanned pollutant traceability ship is powered on and initialized, and the parameters of the unmanned pollutant traceability ship are configured through the remote monitoring base station. If there is no configuration, the default parameters preset in the main control chip are used.

② Wait for the control command, and judge whether it is manual or autonomous navigation mode by receiving the control command sent by the handheld terminal (the default is manual mode). If it is autonomous navigation mode, go to step ③, if it is manual mode, go to step ④.

③The main control chip reads the three-axis magnetic field strength of the electronic compass through the I ² C bus to calculate the orientation of the current unmanned pollutant traceability ship, and then reads the longitude and latitude of the target point sent during the parameter configuration of the monitoring center and the GPS module measurement. The latitude and longitude of the current position is obtained, and these parameters are used as the input parameters of autonomous navigation to control the output of the power system of the unmanned pollutant traceability ship, and the navigation trajectory before the next cycle of the program is obtained. During the driving process, the current movement direction of the unmanned traceability ship is read from the electronic compass and the current GPS coordinates are obtained, and the movement direction of the unmanned traceability ship is continuously corrected until the unmanned traceability ship reaches the destination. After arriving at the destination, stop the power motor and start the pollutant tracking step.

④ If it is manual control, the user can operate the joystick of the handheld remote control to operate the navigation direction and speed of the unmanned pollutant traceability ship very intuitively. The RF wireless module of the unmanned pollutant traceability ship receives and analyzes the information sent by the handheld Instructions, the main control chip outputs corresponding control signals to the power system, so as to complete the forward, backward, left turn, right turn, acceleration and deceleration of the unmanned traceability ship. The unmanned pollutant traceability ship will conduct regular communication checks. If it is found that the control signal has not been received for a long time, it means that the unmanned pollutant traceability ship has driven out of the remote control range of the hand-held remote control, and the signal light of the hand-held remote control will turn red , when the unmanned pollutant traceability ship switches to the autonomous return mode, it will return to the waters where the hand-held remote control signal can be received according to the route point coordinates of the driving track previously recorded in the main control module Flash. At this time, the hand-held remote control The signal light will change to a green flashing signal, indicating that the boat is again manually controllable.

⑤During the operation, upload the current location information to the monitoring center in real time through the GPRS wireless communication module, and call the Baidu map interface in the monitoring center software, and display the real-time location of the unmanned pollutant traceability ship on the software interface, so that users can know that no one is there. The location of the traceability ship.

In the process of operation, in order to improve the accuracy of GPS positioning, there are innovations in the positioning algorithm, and the differential GPS positioning method is used. The GPS positioning data after differential can reduce the impact caused by solar activities, weather changes, and surrounding environmental impacts. public error. Its specific implementation is as follows:

After the unmanned pollutant traceability ship starts, a base station is set up on the shore, equipped with a device of the same type as the ship-borne GPS module to continuously receive GPS positioning signals, and obtain the measured coordinates. This computes coordinate correction values:

$\left\{\begin{array}{c}\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}^{<span\; class="notranslate">\; *</span>}\\ \mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}^{<span\; class="notranslate">\; *</span>}\end{array}\right.$

Where (X ₀ , Y ₀ ) is the precise coordinates of the base station, (X ^* , Y ^* ) is the measured coordinates of the base station, and (ΔX, ΔY) is the coordinate correction value. The reference station sends the correction value to the unmanned pollutant traceability ship through wireless transmission, and the ship’s main control board will correct the GPS positioning coordinates of the ship after receiving it:

$\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; u</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; u</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>\\ {\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; u</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; Y</span>}}_{\mathrm{<span\; class="notranslate">\; u</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&Delta;</span>}\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>\end{array}\right.$

In the formula, is the measured coordinates of the GPS module of the unmanned pollutant traceability ship, and (X _U , Y _U ) is the corrected coordinates of the hull. If the correction value is time-varying, then t ₀ represents the moment when the correction value is generated, and if the correction value is constant, the third term of (X _U , Y _U ) in the formula is 0.

In order to trace the pollutants along the pollution belt to the vicinity of the source as quickly as possible after the pollutants are detected, the algorithm of the "pollution source tracking" module is improved on the basis of the traditional concentration gradient method, making full use of historical detection information and current detection The information formulates direction strategy and step size strategy respectively. Its algorithm flow is shown in Figure 8. Specific steps are as follows:

①Confirm whether the node where the unmanned pollutant traceability ship is located can detect pollutants after taking a step forward to determine whether it is necessary to switch modes. The maximum concentration value and the distance between the three points where the pollutants are finally detected; if the pollutants can be detected, the circle judgment is performed.

② By recording the previous turns, it can be known whether the unmanned pollutant traceability ship is circling. If a circling is found, the forward step length is reduced proportionally to break the circling behavior; at this time step _n = step _n-1 *p , step _n represents the current step size, step _n-1 represents the step size of the last cycle, where p (p<1) is the attenuation coefficient, the test shows that the effect is ideal when the value is 0.9. If there is no circle, perform step ③, if it circles, perform step 5.

③Calculate the change rate of the concentration. In the vicinity of the pollution source, affected by the water flow, the concentration in the downstream of the river is very high. In contrast, the concentration in the upstream will decrease rapidly, forming a large concentration change, and the concentration change rate will form a peak here. The judgment formula is as follows: Among them, c _n represents the detection concentration of the current point, c _n-1 and c _n-2 represent the detection concentration of pollutants in the previous state and the previous two states. If the change rate does not exceed the limit, then perform step ④. If it exceeds the limit, there is If it is possible to reach the pollution source, proceed to the pollution source confirmation step ⑥.

④Adjust the forward step according to the concentration change rate. The specific strategy is as follows: if but ${\mathrm{step}}_{\mathrm{no}}={\mathrm{step}}_{\mathrm{no}-1}*\left(1-a*\log \left|\frac{(c_{\mathrm{no}}-c_{\mathrm{no}-1})/c_{\mathrm{no}-1}}{(c_{\mathrm{no}-1}-c_{\mathrm{no}-2})/c_{\mathrm{no}-2}}\right|\right),$ Otherwise step _n = step _n-1 .

⑤ Determine whether the step size is smaller than the minimum step size. According to the above step size adjustment strategy, if the unmanned pollutant source tracing ship is near the pollution source, the step size will decrease sharply, so if the step size is smaller than the minimum step size, carry out pollution Object confirmation ₍ step ⑥), if it is greater _than the minimum step size, plan the forward route according to the direction strategy. Turn clockwise, then rotate 45° counterclockwise at point n and move forward one step, otherwise rotate 45° clockwise at point n.

⑥The mode of "pollution source confirmation" occurs during the transition from the mode of "pollution source tracking" to the mode of "pollution zone deviation", which is determined by the following three factors: the concentration change rate, concentration value, and the last detected pollutant before deviating from the pollution zone. The distance (step size) between points.

⑦ Proceed to the next cycle and execute step ①.

The above-mentioned embodiments are only descriptions of preferred implementations of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, those skilled in the art may make various modifications and improvements to the present invention. All should expand in the scope of protection as defined in the claims of the present invention.

Claims (3)

1. An unmanned pollutant traceability system, characterized in that it includes an unmanned pollutant traceability ship (7), a handheld remote control (5) and a remote monitoring base station (6), an unmanned pollutant traceability ship (7) Communicate with the remote monitoring base station (6) through GPRS, and the unmanned pollutant traceability ship (7) communicates wirelessly with the hand-held remote control (5) through radio frequency communication; the unmanned pollutant traceability ship includes the hull (4), main control Unit (1), water body sampling device (2) and water quality on-line detection device (3), the hull (4) is composed of a hull shell, a power unit and a power module, and adopts a catamaran type, and the main control unit ( 1) It consists of main control chip, GPRS module, RF wireless module, GPS module, electronic compass, steering gear drive DC motor drive, stepper motor drive and JTAG interface, wherein the GPRS module, RF wireless module, GPS module and The main control chip is connected with the RS232 interface, and the electronic compass is connected with the main control chip through the I ² C interface; the water body sampling device (2) is composed of a lifting device, a sampling device and a flow distribution device, and the lifting device is composed of a sampling hose, a step Inlet motor, reel, transmission device, sampling device is composed of peristaltic pump, two-way joint, diversion device is composed of steering gear, diversion plate and water tank, the water quality online detection device (3): mainly consists of submerged probe and signal Composed of an acquisition circuit, the online detection device (3) is connected to the main control unit (1) through the RS485 interface, and transmits the detection information to the main control unit (1); the handheld remote control consists of a main control chip, an RF wireless module, a programmable Joystick, programmable buttons, LCD screen, RS232 interface circuit, JTAG interface and power supply module, the RF wireless module is connected to the main control chip through the RS232 interface circuit, programmable rocker, programmable buttons, LCD screen Connected with the main control chip, the remote monitoring base station can be composed of an ordinary PC with a fixed external network IP and monitoring center software. 2. An unmanned pollutant traceability method using the system according to claim 1, characterized in that its steps are as follows: 1) Startup: After the unmanned pollutant traceability ship is started, when the user knows the approximate location of the pollution zone, he can quickly reach the pollution zone through manual control or autonomous navigation, narrow the search range, and speed up the progress of pollution source location. If the user does not know Where the pollution source is located, the unmanned source tracing ship will advance several meters against the current or obliquely against the current, which will be used as the starting point for the traceability of pollutants; 2) Pollution zone search: If no pollutants are found after the initial step length after the unmanned pollutant traceability ship starts, the unmanned pollutant tracer ship will search the entire river section upstream until no one pollutes. The on-line detection device carried by the material traceability ship detects pollutants, and then enters the "pollution source tracking" mode; 3) Pollution source tracking: the unmanned pollutant traceability ship uses the historical pollutant concentration data, historical direction data, historical step data and current pollutant concentration data stored in the main control chip to formulate the current direction strategy and step strategy, If the tracking process does not deviate from the pollution zone, the current pollutant concentration, direction and step data detected by the online detection device are stored in the main control chip, become historical data, and enter the next pollutant tracking cycle. If it deviates from the pollution zone, then Enter the "pollution zone deviation" mode; 4) Pollution zone deviation: to prevent the divergence of the tracking path. After entering this mode, the unmanned pollutant traceability ship must first confirm the pollution source. If the conditions are not met, the pollution zone will be searched again, and the "pollution source tracking" mode will be entered again; 5) Pollution source confirmation: Use the pollutant concentration value, the concentration change rate value, and the distance threshold between the point where the pollutant was last detected before departing from the pollution zone as the basis for confirming the pollution source, and judge whether the location is a pollution source. Pollution zone search", if it is a pollution source, the coordinates of the position located by GPS will be sent to the remote monitoring center, and the traceability process of pollutants is over. 3. A method for unmanned pollutant traceability as claimed in claim 2, characterized in that, said step 1) is: there are two control modes for starting, namely: two motion control modes of manual remote control and autonomous navigation, The two control methods can be switched by the manual automatic switch button on the handheld remote control (5), and in the manual mode, the unmanned pollutant source tracing ship (7) will regularly perform communication verification. The control signal, the unmanned pollutant traceability ship switches to the autonomous navigation mode, and will return to the water area that can receive the signal of the hand-held remote control (5) according to the coordinates of the passing points of the driving track recorded in the main control module Flash. The GPS positioning method used in the navigation motion control mode, in order to improve the accuracy of GPS positioning, also has innovations in the positioning algorithm: using the differential GPS positioning method, the GPS positioning data after the difference reduces the risk caused by solar activity, weather changes, and the surrounding environment. Public errors caused by influence, etc.