Passive parent-child forest fire situation awareness system and method based on thermoelectric conversion

Abstract

The present application relates to a passive parent-child forest fire situation awareness system and method based on thermoelectric conversion. The system comprises a plurality of parent stations, a plurality of child stations corresponding to each parent station, and a monitoring station; each child station is used to generate electricity by using thermoelectric materials at the critical temperature, and trigger the on-off circuit of the constant temperature blasting switch to output the fire alarm instruction to the signal transmission unit; the signal transmission unit generates the corresponding fire alarm signal according to the fire alarm instruction and sends it to the signal processing unit of the parent station through wireless transmission; the fire alarm signal includes the position of the child station and the fire sensing time; each parent station is used to receive the fire alarm signal sent by each child station and send it to the monitoring station through satellite or base station; the monitoring station is used to receive the fire alarm signal sent by the satellite or base station, and analyze the fire alarm signal to assist the command personnel to make fire fighting decisions. The system can timely transmit the early warning signal and effectively realize early warning before the fire expands.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mountain forest fire monitoring, in particular to a passive parent-child type mountain fire situation awareness system and method based on thermoelectric conversion. BACKGROUND

[0002] The harm caused by mountain fires is multifaceted, mainly manifested in: 1. Mountain fires cause serious loss of life and property 2. Mountain fires cause serious damage to the ecological environment 3. Mountain fires pose a threat to the survival environment of wild animals and plants, affecting biodiversity and the stability of the ecological system.

[0003] However, through investigation, it is found that if early warning and disposal are made in the early stage of mountain fires, the harmfulness can be greatly reduced. The earlier the fire is discovered, the less the loss caused by the fire. Mountain fire monitoring is an important disaster prevention and mitigation work. Various ways are used for mountain fire monitoring at home and abroad, such as satellite remote sensing monitoring, unmanned aerial vehicle remote sensing monitoring, ground monitoring station monitoring, and wireless sensor network monitoring. However, the area of mountains and forests is large, the terrain changes greatly, and the vertical plane is complex. The areas far from the detection tower are difficult to be fully checked. At present, the forest fire alarm system needs a lot of manpower, material resources and financial support, and there may be cases of not discovering in time due to human negligence. Therefore, it is necessary to design a fire alarm system that is convenient for real-time and large-scale monitoring. SUMMARY

[0004] Therefore, it is necessary to provide a passive parent-child type mountain fire situation awareness system and method based on thermoelectric conversion in view of the above technical problems.

[0005] A passive parent-child type mountain fire situation awareness system based on thermoelectric conversion, the system comprising a plurality of parent stations, a plurality of child stations corresponding to each parent station, and a monitoring station; each parent station and child station is placed at a corresponding position in the mountains and forests according to a pre-set parent-child station layout; the layout is obtained by simulating historical fire data of the mountains and forests;

[0006] Each child station comprises a sensing trigger unit and a signal transmission unit; the sensing trigger unit comprises a thermoelectric material, a battery, and a constant-temperature blasting switch, for generating electricity by the thermoelectric material at a critical temperature, triggering the constant-temperature blasting switch to turn on the circuit, and outputting a fire alarm instruction to the signal transmission unit; the signal transmission unit is used for generating a corresponding fire alarm signal according to the fire alarm instruction and sending the signal to the signal processing unit of the parent station through wireless transmission; the fire alarm signal comprises the position of the child station and the fire perception time;

[0007] Each parent station comprises a power supply and a signal processing unit; the signal processing unit comprises a wireless signal receiving module and a satellite communication module, for receiving the fire alarm signal sent by each child station and sending it to the monitoring station through a satellite or a base station;

[0008] The monitoring station comprises an indication unit configured to receive a fire alarm signal sent by a satellite or a base station and analyze the fire alarm signal to assist a commander in making a fire fighting decision.

[0009] In one of the embodiments, the method further comprises: obtaining mountain and forest terrain information, and calculating a mother station layout scheme that satisfies the minimization of the number of mother stations and the maximization of mountain and forest coverage based on the mountain and forest terrain information and the supervision range of the mother station; obtaining historical fire data of the mountain and forest, and establishing a fire spread speed model based on the historical fire data; initializing the layout of each sub-station in the supervision range of each mother station to obtain the position of each sub-station; calculating a sub-station layout scheme that satisfies the minimization of communication distance based on the fire spread speed model and the position of each sub-station in the supervision range of each mother station; and obtaining a sub-mother station layout mode based on the mother station layout scheme and the sub-station layout scheme corresponding to each mother station.

[0010] In one of the embodiments, the fire spread speed model is:

[0011] ;

[0012] wherein, is the fire spread speed, is the maximum spread speed, is the spread speed constant, is the time, is the noise disturbance.

[0013] In one of the embodiments, the thermoelectric material generates electricity under the condition of temperature difference between the sunny side and the shady side and stores the electricity into the storage battery.

[0014] In one of the embodiments, the constant-temperature blasting switch releases the switch constraint and turns on the circuit when the temperature reaches the critical temperature.

[0015] In one of the embodiments, the signal transmission unit comprises a single-chip microcomputer and a wireless signal transmission module; the single-chip microcomputer is configured to receive a fire alarm instruction sent by the induction trigger unit and perform a fire alarm operation based on the fire alarm instruction; the fire alarm operation comprises generating a fire alarm signal based on current timestamp information and sub-station position information and sending the fire alarm signal to the wireless signal transmission module; and the wireless signal transmission module is configured to send the fire alarm signal to the corresponding mother station.

[0016] In one of the embodiments, the method further comprises: analyzing the received fire alarm signal to obtain timestamp information and sub-station position information; and performing a fire fighting task to the corresponding sub-station position based on the earliest timestamp information.

[0017] A passive parent-child forest fire situation awareness method based on thermoelectric conversion, the method comprising:

[0018] Each parent station and child station is placed at the corresponding position of the mountain forest according to a pre-set parent-child station layout mode, which is obtained by simulating historical forest fire data of the mountain forest;

[0019] The thermoelectric material of each child station generates electricity at the critical temperature, triggers the on-circuit output of the constant-temperature blasting switch, generates a corresponding fire alarm signal according to the fire alarm instruction, and sends the signal to the parent station through wireless transmission; the fire alarm signal includes the position of the child station and the fire awareness time;

[0020] Each parent station receives the fire alarm signal sent by each child station and sends it to the monitoring station through a satellite or a base station;

[0021] The monitoring station receives the fire alarm signal sent by the satellite or the base station and analyzes the signal to assist the command personnel in making fire rescue decisions.

[0022] In one embodiment, the method further comprises: obtaining mountain forest terrain information, calculating a parent station layout scheme that satisfies the minimization of the number of parent stations and the maximization of the coverage rate of the mountain forest according to the mountain forest terrain information and the monitoring range of the parent station; obtaining historical forest fire data, establishing a fire spread speed model according to the historical forest fire data; initializing the layout of each child station within the monitoring range of each parent station to obtain the position of each child station; calculating a child station layout scheme that satisfies the minimization of the communication distance according to the fire spread speed model and the position of each child station within the monitoring range of each parent station; obtaining a parent-child station layout mode according to the parent station layout scheme and the corresponding child station layout scheme of each parent station.

[0023] In one embodiment, the method further comprises: the fire spread speed model is:

[0024] ;

[0025] wherein, is the fire spread speed, is the maximum spread speed, is the spread speed constant, is time, is noise disturbance. A passive parent-child forest fire situation awareness device based on thermoelectric conversion, the device comprising:

[0026] The passive parent-child type mountain fire situation perception system and method based on thermoelectric conversion can realize efficient fire situation perception according to mountain forest characteristics through the pre-set parent-child station layout mode, and can effectively reduce the expenditure of manpower and material resources after the parent-child station is laid out without other resource input, the thermoelectric material and constant temperature explosion switch of the child station provide double fire situation insurance, the probability of false alarm is greatly reduced, the signal is transmitted between the parent-child stations in a wireless mode, each parent station provides information transmission bridge for the child stations and monitoring stations in the coverage range, the signal transmission time is shortened, and the position information and fire situation occurrence time of the child station where the fire occurs can be transmitted to the monitoring station in time. The embodiment of the present application can timely emit the early warning signal, and effectively realize early warning before the fire expands. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 FIG. 1 is a structural schematic diagram of a passive parent-child type mountain fire situation perception system based on thermoelectric conversion in an embodiment;

[0028] Figure 2 FIG. 3 is a schematic diagram of a thermoelectric conversion principle in an embodiment;

[0029] Figure 3 FIG. 5 is an air drop schematic diagram of a parent-child station in an embodiment;

[0030] Figure 4 FIG. 7 is a structural schematic diagram of a parent station in an embodiment;

[0031] Figure 5 FIG. 9 is a working schematic diagram of a passive parent-child type mountain fire situation perception system based on thermoelectric conversion in an embodiment;

[0032] Figure 6 FIG. 11 is a structural schematic diagram of a passive parent-child type mountain fire situation perception system based on thermoelectric conversion in a specific embodiment;

[0033] Figure 7 FIG. 13 is a flow schematic diagram of a parent-child station layout setting in an embodiment;

[0034] Figure 8 FIG. 15 is a flow schematic diagram of a passive parent-child type mountain fire situation perception method based on thermoelectric conversion in an embodiment. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0036] In an embodiment, as shown in FIG. 1, the passive parent-child type mountain fire situation perception system based on thermoelectric conversion comprises a parent station and a plurality of child stations. Figure 1As shown, a passive parent-child forest fire situation awareness system based on thermoelectric conversion is provided, the system comprising a plurality of parent stations, a plurality of child stations corresponding to each parent station, and a monitoring station; each parent station and child station is placed at a corresponding position in the forest according to a pre-set parent-child station layout mode; the layout mode is obtained by simulating historical forest fire data;

[0037] Each child station comprises an induction triggering unit and a signal transmission unit; the induction triggering unit comprises a thermoelectric material, a battery, and a constant-temperature blasting switch, for generating electricity by the thermoelectric material at a critical temperature, triggering the constant-temperature blasting switch to turn on the circuit to output a fire alarm instruction to the signal transmission unit; the signal transmission unit is used to generate a corresponding fire alarm signal according to the fire alarm instruction and send it to the signal processing unit of the parent station through wireless transmission; the fire alarm signal comprises the position of the child station and the fire perception time;

[0038] Each parent station comprises a power supply and a signal processing unit; the signal processing unit comprises a wireless signal receiving module and a satellite communication module, for receiving the fire alarm signal sent by each child station and sending it to the monitoring station through a satellite or a base station;

[0039] The monitoring station comprises an indication unit, for receiving the fire alarm signal sent by the satellite or the base station and analyzing the fire alarm signal to assist the command personnel in making fire fighting decisions.

[0040] In the above passive parent-child forest fire situation awareness system based on thermoelectric conversion, the parent-child station layout according to the pre-set parent-child station layout mode can achieve efficient fire perception according to the characteristics of the forest, and after the parent-child stations are laid out, no other resources are needed, which can effectively reduce the expenditure of manpower and material resources, the thermoelectric material and the constant-temperature blasting switch of the child station provide double fire insurance, greatly reducing the probability of false alarms, the signals are transmitted between the parent-child stations in a wireless manner, each parent station provides a bridge for information transmission for the child stations and the monitoring station within the coverage range, shortening the signal transmission time and enabling the position information and the fire occurrence time of the child station where the fire occurs to be transmitted to the monitoring station in a timely manner. The embodiment of the present application can timely emit a warning signal to effectively achieve early warning before the fire spreads.

[0041] In one embodiment, the thermoelectric material generates electricity under the condition that there is a temperature difference between the sunny side and the shady side, and stores it in the battery. In this embodiment, the thermoelectric material converts the temperature difference into electrical energy, the battery stores the electrical energy generated by the thermoelectric material, and the battery releases electrical energy at any time according to the demand, which not only reduces the need for maintenance and replacement of the battery, but also enables fire perception. Figure 6 In the embodiment shown, the battery is embodied in the form of a capacitor.

[0042] Specifically, the substation adopts a complementary way of thermoelectric material and battery. Daily, the thermoelectric material generates electricity through the temperature difference between the sunny side and the shady side, and the charged battery is not powered on. When a fire occurs, the battery can be charged again by using the drastic temperature change, ensuring that the power reserve can meet the alarm needs. Figure 2 As shown in the thermoelectric conversion principle diagram, the thermoelectric conversion system utilizes the thermoelectric conversion (Seebeck) principle to select specific thermoelectric materials to generate electricity. When the forest fire spreads to the sensing range, the thermoelectric material is heated, and electricity is generated due to the temperature difference between the inside and outside, providing power for the system.

[0043] In one embodiment, the constant-temperature blasting switch releases the switch constraint when the temperature reaches the critical temperature, and turns on the circuit. In this embodiment, the working principle of the constant-temperature blasting switch is mainly based on temperature sensing material. When the ambient temperature reaches or exceeds its set temperature, the sensing material will change physically (such as melting, breaking), thereby making the circuit conductive. The constant-temperature blasting switch triggers immediately when it reaches the critical temperature, which can ensure that the alarm is realized before the system is burned out.

[0044] Specifically, the constant-temperature blasting switch adopts a thermosensitive medium glass bottle scheme. The glass bottle is located at the bottom of the subsystem. When the outside catches fire, the temperature of the bottle reaches the preset temperature, and the content expands to make the glass bottle burst, the switch constraint is released, and the circuit can be turned on to start transmitting the fire signal to the parent system.

[0045] The system utilizes the temperature limit of the temperature sensing material to distinguish between forest fires and general ambient temperatures. The circuit is turned on only when the temperature reaches a certain threshold, effectively realizing fire sensing. The thermoelectric conversion material generates electricity to power when sensing the fire, effectively avoiding the situation that the switch is opened due to falling, wild animal trampling, and biting, triggering the alarm, realizing double insurance design, and avoiding false alarm.

[0046] In one embodiment, the signal transmission unit includes a single-chip microcomputer and a wireless signal transmission module; the single-chip microcomputer is used to receive the fire alarm instruction sent by the sensing trigger unit, and execute the fire alarm operation according to the fire alarm instruction; the fire alarm operation includes generating a fire alarm signal according to the current timestamp information and the substation position information, and sending the fire alarm signal to the wireless signal transmission module; the wireless signal transmission module is used to send the fire alarm signal to the parent station.

[0047] In this embodiment, a GPS module is arranged in the single-chip microcomputer, and the substation positioning is realized through the GPS module to provide the substation position information.

[0048] In one embodiment, the parent station is powered by solar energy without additional energy input.

[0049] It can be understood that the power supply of the parent station can also be realized by a battery.

[0050] In one embodiment, the sub-station and the parent station use WIFI6-based signal transmission units and signal processing units for communication.

[0051] In one embodiment, as shown in the sub-mother station air drop schematic diagram, Figure 3 the unmanned aerial vehicle drops the sub-station and the parent station according to the pre-set sub-mother station layout mode, and the sub-station and the parent station are hung on corresponding parachutes. In this embodiment, the unmanned aerial vehicle drops according to the designed layout density along the planned route, and the equipment is hung on the tree through parachute drop, which can realize sensitive monitoring of forest fires. Due to the large area of forest and complex environment, the existing early warning scheme needs high investment cost whether it is remote sensing monitoring or manual patrol. The passive monitoring principle is adopted in this system, and no other resource input is needed after deployment, which can effectively reduce the expenditure of manpower and material resources. According to the design cost of about 1000 yuan per square kilometer required by the equipment according to the preset density, the cost will be lower after mass production. The parent station mainly includes a power supply system and a signal processing system, as shown in the parent station structure schematic diagram, Figure 4 the flexible photovoltaic panel is covered on the surface of the parachute to supply power for the device, ensuring all-weather monitoring of multiple sub-stations. The parent station adopts a parachute structure, which can be accurately placed in the arbor layer of the forest while reducing the impact on the natural environment, and is convenient for absorbing solar energy and realizing green environmental protection. In the embodiment of the application, the system is deployed in the forest and can monitor the fire situation for 24 hours without interruption, and the passive sub-mother station signal transmission structure can transmit the early warning signal within 30 minutes, which can effectively realize early warning before the fire expands.

[0052] In one specific embodiment, as shown in the working schematic diagram of the passive sub-mother station forest fire situation awareness system based on thermoelectric conversion, Figure 5 the specific working process of the overall system is as follows:

[0053] S1, precise network arrangement of the system in the forest is realized through unmanned aerial vehicle air drop;

[0054] S2, after deployment, the subsystem charges the battery through the temperature difference of environmental change, and the parent system realizes all-weather work through the complementary mode of solar energy and battery;

[0055] S3, when a fire occurs in a certain area, the subsystem senses the temperature change, generates electric energy through the thermoelectric conversion device, and combines the battery power supply to transmit the disaster location signal to the parent system;

[0056] S4, the parent system transmits the position information to the monitoring station through satellite or base station, realizing timely early warning of forest fires.

[0057] In this embodiment, as shown in Figure 6The structure diagram of the passive parent-child forest fire situation awareness system based on thermoelectric conversion is shown. The subsystem mainly consists of a sensing trigger unit composed of thermoelectric conversion materials and a constant temperature blasting switch, and a signal transmission unit based on WIFI6. The monitoring station can be connected to a computer to realize the functions of information analysis, disaster location and alarm. The subsystem is normally in no power consumption, and the parent system stores energy through photovoltaic panels, monitors the subsystem all day long, and maintains communication with the monitoring station through satellites, base stations and other means. The parent-child structure fully utilizes the performance of communication technology, saves a lot of cost of laying high-precision satellite communication modules, and makes it possible to lay more dense subsystems and monitor disasters more sensitively.

[0058] The parent-child station adopts a many-to-one relationship, that is, one parent system and several subsystems are laid in one area (the specific distribution scheme can be obtained by mathematical modeling), and information transmission is carried out between the parent-child stations through WIFI6. Any subsystem in the monitoring area covered by the parent system signal can alarm, and the parent system can receive the signal and timely inform the forest monitoring station. Using WIFI6 module can realize the detection of substation signal within a range of more than 200 meters. After receiving the alarm information, the disaster situation is transmitted to the monitoring station through the 4G module or satellite communication module, and the monitoring station realizes the functions of information analysis, disaster location and alarm.

[0059] Compared with the existing forest fire alarm technology, the system has more timely fire warning, more accurate warning position and lower running cost. By controlling the temperature limit of the glass bottle, the mountain fire and the high temperature environment (no power supply) can be distinguished; by using thermoelectric conversion material to control power supply, the situation that the switch is opened to trigger alarm due to falling, trampling and biting of wild animals (power supply) can be avoided.

[0060] In one embodiment, analyzing the fire alarm signal to assist the command personnel to execute the fire fighting decision includes: analyzing the received fire alarm signal to obtain timestamp information and substation position information; and executing the fire fighting task to the corresponding substation position according to the earliest timestamp information.

[0061] In this embodiment, the fire alarm signal includes fire sensing time and substation position, wherein the fire sensing time refers to the time when the substation senses the occurrence of fire, and the timestamp information is obtained based on the time. An embedded system based on stm32 is designed according to the actual needs of alarm, and various modules are loaded to realize the normal operation of various functions. And the terminal alarm and ignition point position query software based on VisualBasic6.0 is designed, which can analyze the alarm information transmitted by the monitoring station in the first time, realize automatic alarm, visual positioning, disaster spreading trend analysis and other functions.

[0062] In one embodiment, as Figure 7The flowchart of the sub-mother station layout shown, the steps of setting the sub-mother station layout mode include: obtaining mountain forest terrain information, calculating the mother station layout scheme that satisfies the minimization of the number of mother stations and the maximization of the mountain forest coverage rate according to the mountain forest terrain information and the mother station supervision range; obtaining mountain forest historical fire data, establishing a fire spread speed model according to the historical fire data; initializing the layout of each sub-station in each mother station supervision range to obtain the position of each sub-station; calculating the sub-station layout scheme that satisfies the minimization of the communication distance according to the fire spread speed model and the position of each sub-station in each mother station supervision range; obtaining the sub-mother station layout mode according to the mother station layout scheme and the corresponding sub-station layout scheme of each mother station.

[0063] Specifically, if there is no historical fire, the fire spread speed model can also be simulated according to the actual situation of the mountain forest. Due to the limited communication distance, the sub-station must be arranged within a radius of 200 meters from the center of the mother station to ensure signal transmission. The sub-mother station layout needs to consider two problems:

[0064] Problem one: considering the arrangement of sub-stations within a radius of 200 meters from the center of the mother station.

[0065] Problem two: considering the circular coverage problem of the 200-meter radius circle in the entire mountain forest.

[0066] For problem one, the optimization goal is to make the distance from any point in the circle to its nearest sub-station as small as possible, so that no matter where the fire occurs, it can be detected by the nearby sub-station in the shortest time, thereby minimizing the communication distance. In order to solve this problem, that is, "how to arrange multiple fire sensing devices within a circle to ensure that any point in the circle can be sensed by the device as quickly as possible when a fire occurs", we need to set a suitable fitness function for the genetic algorithm to ensure that the layout of the sensing device can minimize the maximum distance from any point in the circle to the nearest sensing device.

[0067] The fitness function should reflect the optimization of the layout scheme for the fire sensing speed. A reasonable measure is the maximum distance from any point in the circle to its nearest sensing device, and we want this distance to be as small as possible. Therefore, the fitness function can be designed as:

[0068] 1. For each point, calculate the distance to multiple sensing devices and take the minimum value.

[0069] 2. Sample multiple points in the entire circle area (or use mathematical methods to calculate the maximum possible distance), find the maximum value in these minimum distances.

[0070] 3. The goal of the fitness function is to minimize this maximum distance, expressed as:

[0071] F = max(min(d(p, s_i)|i=1,2,…,N )|p∈circle)

[0072] where (d(p, s_i)) is the distance from point (p) to sensor (s_i), Circle represents the area of a circle. This formula expresses that among all the possible points in the circular area, the one that is closest to the nearest sensor is determined, and the maximum distance is achieved. In practical applications, to simplify the calculation, the circular area can be discretized, i.e., a certain number of representative points are selected to approximate the maximum distance.

[0073] Based on the above fitness function, we can design the steps of the genetic algorithm as follows:

[0074] Step 1 Initialize the population: randomly generate an initial set of coordinates that satisfy the boundary conditions.

[0075] Step 2 Evaluate fitness: calculate the fitness value of each coordinate in the population, i.e., call the fitness function to determine whether each point is as close to the coordinate as possible.

[0076] Step 3 Selection operation: select appropriate coordinates based on the fitness value to enter the next round.

[0077] Step 4 Mutation operation: randomly mutate the selected coordinate individuals to increase the diversity of the coordinate population.

[0078] Step 5 Recombination operation: generate new individuals by combining the characteristics of different coordinate individuals.

[0079] Step 6 Iterative optimization: repeat Steps 2-5 until the preset number of iterations is reached or the stopping condition is met.

[0080] Step 7 Output results: return the coordinates with the best fitness as the final result.

[0081] For problem two, the goal is to find out how to use the least number of fixed-radius mother stations to cover a given irregular mountainous area, thereby minimizing the number of mother stations and maximizing the coverage rate of the mountainous area. This problem can be solved by using a greedy algorithm to find the optimal solution. Here, an irregular pentagon is used to simulate the mountainous area. The specific steps are as follows:

[0082] STEP 1 Initialize an empty covered area and an empty detector list.

[0083] STEP 2 Create a grid point set within the polygon area, which is used to evaluate which areas have been covered.

[0084] STEP3 Enter a loop, continue as long as there are uncovered polygon regions.

[0085] STEP4 In each loop, find all the uncovered grid points, and randomly select one as the center of the new detector.

[0086] STEP5 Record the position and radius of this new detector into the detector list, and update the covered region.

[0087] In an embodiment, the fire spread speed model is:

[0088] ;

[0089] wherein, is the fire spread speed, is the maximum spread speed, is the spread speed constant, is the time, is the noise disturbance.

[0090] In the present embodiment, the fire spread speed model takes into account the change of the speed of flame spread over time, the spread speed of forest fire spread is related to the fire, the greater the fire, the faster the spread speed in the early spread. And the fire can be regarded as increasing with time. And the forest fire spread speed has a corresponding upper limit, and will not continue to increase after reaching a certain speed. Based on this, the fire spread speed model is constructed to simulate the process of flame from occurrence to spread to the substation.

[0091] In an embodiment, as shown in Figure 8 , a passive parent-child forest fire situation awareness method based on thermoelectric conversion is provided, comprising the following steps:

[0092] Step 802, according to the pre-set sub-station layout mode, each parent station and sub-station is placed in the corresponding position of the mountain forest.

[0093] The layout mode is obtained by simulating the historical fire data of the mountain forest.

[0094] Step 804, the thermoelectric material of each sub-station generates electricity at the critical temperature, and triggers the constant temperature blasting switch to turn on the circuit output fire alarm instruction, generates the corresponding fire alarm signal according to the fire alarm instruction, and sends it to the parent station through wireless transmission.

[0095] The fire alarm signal includes the position of the sub-station and the fire situation awareness time.

[0096] Step 806, each parent station receives the fire alarm signal sent by each sub-station and sends it to the monitoring station through the satellite or base station.

[0097] At step 808, the monitoring station receives the fire alarm signal sent by the satellite or the base station, and parses the fire alarm signal to assist the commander to make a fire fighting decision.

[0098] It should be understood that, although Figure 8 The steps in the flowcharts of the above embodiments are shown in sequence according to the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, Figure 8 At least part of the steps in the above embodiments can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of these sub-steps or stages is not necessarily sequential, but can be executed in rotation or alternation with other steps or at least part of the sub-steps or stages of other steps.

[0099] The technical features of the above embodiments can be combined in any manner. In order to make the description concise, all possible combinations of the technical features in the above embodiments are not described, but as long as the combinations of the technical features do not contradict, they should be considered as the scope of the present disclosure.

[0100] The above embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the present application. It should be pointed out that, for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A passive parent-child wildfire situation awareness system based on thermoelectric conversion, characterized in that: The system includes multiple mother stations, several substations corresponding to each mother station, and a monitoring station. Each mother station and substation are placed at corresponding locations in the forest according to a pre-set mother-substation layout; the layout is derived from simulation of historical forest fire data. Each substation includes an induction trigger unit and a signal transmission unit; the induction trigger unit includes thermoelectric materials, batteries, and a constant-temperature blasting switch, which is used to generate electricity using the thermoelectric materials at a critical temperature and trigger the constant-temperature blasting switch to conduct the circuit and output the fire alarm instruction to the signal transmission unit; the signal transmission unit is used to generate a corresponding fire alarm signal according to the fire alarm instruction and send it to the signal processing unit of the mother station via wireless transmission; the fire alarm signal includes the substation location and the time when the fire was detected; Each mother station includes a power supply and a signal processing unit; the signal processing unit includes a wireless signal receiving module and a satellite communication module, which is used to receive the fire alarm signal sent by each substation and send it to the monitoring station via satellite or base station; The monitoring station includes an indication unit for receiving fire alarm signals sent by satellites or base stations and analyzing the fire alarm signals to assist command personnel in making firefighting decisions; The steps to set up a parent-child station layout include: Obtain mountain and forest terrain information, and calculate the mother station layout plan based on the mountain and forest terrain information and the mother station supervision range to minimize the number of mother stations and maximize the mountain and forest coverage; Obtain historical forest fire data and establish a fire spread rate model based on the historical fire data; Initialize the layout of each substation within the supervision range of each mother station and obtain the location of each substation; A substation layout plan that satisfies the minimum communication distance is calculated based on the fire spread speed model and the location of each substation within the supervision range of each mother station; The layout of the mother and child stations is obtained according to the mother station layout plan and the substation layout plan corresponding to each mother station.

2. The system according to claim 1, wherein: The fire spread speed model is: in, is the fire spread rate, is the maximum spreading speed, is the spreading rate constant, For time, is noise disturbance.

3. The system according to claim 1, wherein: The thermoelectric material generates electricity when there is a temperature difference between the sun-facing side and the sun-shading side, and stores the electricity in the battery.

4. The system according to claim 1, wherein: The constant temperature blasting switch releases the switch constraint and turns on the circuit when the temperature reaches a critical temperature.

5. The system according to claim 1, wherein: The signal transmission unit includes a single chip microcomputer and a wireless signal transmission module; The single chip microcomputer is used to receive the fire alarm instruction sent by the induction trigger unit and perform a fire alarm operation according to the fire alarm instruction; the fire alarm operation includes generating a fire alarm signal according to the current timestamp information and the substation location information, and sending the fire alarm signal to the wireless signal transmission module; The wireless signal transmission module is used to send the fire alarm signal to the mother station to which it belongs.

6. The system according to claim 1, wherein: Analyzing fire alarm signals to assist commanders in making firefighting decisions includes: Parse the received fire alarm signal to obtain timestamp information and substation location information; Execute the firefighting task to the corresponding substation location according to the earliest timestamp information.

7. A passive parent-child wildfire situation awareness method based on thermoelectric conversion implemented in the system of claim 1, characterized in that: The method comprises: Each mother station and daughter station are placed at corresponding locations in the forest according to a pre-set mother-daughter station layout; the layout is obtained by simulating historical forest fire data; At the critical temperature, the thermoelectric material of each substation generates electricity, triggering the fixed-temperature blasting switch to conduct the circuit and output a fire alarm instruction. According to the fire alarm instruction, a corresponding fire alarm signal is generated and sent to the corresponding mother station via wireless transmission; the fire alarm signal includes the substation location and the time when the fire was detected; Each mother station receives the fire alarm signal sent by each substation and sends it to the monitoring station via satellite or base station; The monitoring station receives fire alarm signals sent by satellites or base stations, and analyzes the fire alarm signals to assist command personnel in making firefighting decisions; The steps to set up a parent-child station layout include: Obtain mountain and forest terrain information, and calculate the mother station layout plan based on the mountain and forest terrain information and the mother station supervision range to minimize the number of mother stations and maximize the mountain and forest coverage; Obtain historical forest fire data and establish a fire spread rate model based on the historical fire data; Initialize the layout of each substation within the supervision range of each mother station and obtain the location of each substation; A substation layout plan that satisfies the minimum communication distance is calculated based on the fire spread speed model and the location of each substation within the supervision range of each mother station; The layout of the mother and child stations is obtained according to the mother station layout plan and the substation layout plan corresponding to each mother station.

8. The method according to claim 7, characterized in that The fire spread speed model is: in, is the fire spread rate, is the maximum spreading speed, is the spreading rate constant, For time, is noise disturbance.

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