Passive child-mother type forest fire situation sensing system and method based on thermoelectric conversion

Abstract

The invention relates to a passive child-mother type forest fire situation sensing system and method based on thermoelectric conversion. The system comprises a plurality of primary stations, a plurality of secondary stations corresponding to each primary station and a monitoring station, each substation is used for generating power by using a thermoelectric material at a critical temperature and triggering a constant-temperature explosion switch conduction circuit to output a fire alarm instruction to the signal transmission unit; the signal transmission unit generates a corresponding fire alarm signal according to the fire alarm instruction and sends the fire alarm signal to the signal processing unit of the master station in a wireless transmission mode; the fire alarm signal comprises a substation position and fire sensing time; each mother station is used for receiving a fire alarm signal sent by each substation and sending the fire alarm signal to the monitoring station through a satellite or a base station; and the monitoring station is used for receiving the fire alarm signal sent by the satellite or the base station and analyzing the fire alarm signal to assist a commander in executing a fire fighting decision. By adopting the system, an early warning signal can be emitted in time, and early warning can be effectively realized before the fire behavior is expanded.

Description

Technical Field

[0001] The present invention relates to the technical field of forest fire monitoring, and in particular to a passive parent-child forest fire situation perception system and method based on thermoelectric conversion. Background Art

[0002] Frequent wildfires have brought profound suffering to the people of the world. The harm caused by wildfires is multifaceted, mainly manifested in: 1. Wildfires cause serious loss of life and property 2. Wildfires cause serious damage to the ecological environment 3. Wildfires threaten the living environment of wild animals and plants, affecting biodiversity and the stability of the ecosystem.

[0003] However, after investigation, it was found that if early warning and disposal are carried out in the early stage of wildfire, its harmfulness can be greatly reduced. The earlier the fire is discovered and the timely intervention is made, the smaller the loss caused by the fire. Wildfire monitoring is an important disaster prevention and mitigation work. Various methods are used for wildfire monitoring at home and abroad, such as satellite remote sensing monitoring, drone remote sensing monitoring, ground monitoring station monitoring and wireless sensor network monitoring. However, the mountain forest area is large, the terrain changes greatly, the vertical structure is complex, and the area far away from the detection tower is difficult to be fully inspected. The current forest fire alarm system requires a lot of manpower, material and financial support, and there may be situations where the fire is not discovered in time due to factors such as human negligence. Therefore, it is very necessary to design a fire alarm system that is easy to monitor in real time and over a large area. Summary of the invention

[0004] Based on this, it is necessary to provide a passive mother-and-child forest fire situation awareness system and method based on thermoelectric conversion to address the above technical problems.

[0005] A passive parent-child forest fire situation awareness system based on thermoelectric conversion, the system includes multiple mother stations, several child stations corresponding to each mother station, and a monitoring station; each mother station and child station are placed at corresponding positions in the forest according to a pre-set mother-child station layout; the layout is obtained by simulating historical fire data of the forest;

[0006] Each substation includes an induction trigger unit and a signal transmission unit; the induction trigger unit includes thermoelectric materials, batteries and constant temperature explosion switches, which are used to generate electricity using thermoelectric materials at critical temperatures, and trigger the constant temperature explosion switch to conduct the circuit to 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 through wireless transmission; the fire alarm signal includes the substation location and the fire perception time;

[0007] 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 are used to receive the fire alarm signal sent by each substation and send it to the monitoring station via a satellite or base station;

[0008] The monitoring station includes an indicating unit, which is used to receive fire alarm signals sent by satellites or base stations, and analyze the fire alarm signals to assist command personnel in executing firefighting decisions.

[0009] In one of the embodiments, it also includes: obtaining mountain and forest terrain information, and calculating a mother station layout plan that minimizes the number of mother stations and maximizes forest coverage based on the mountain and forest terrain information and the mother station supervision range; obtaining historical forest fire data, and establishing a fire spread rate model based on the historical fire data; initializing the layout of each substation within the supervision range of each mother station to obtain the location of each substation; calculating a substation layout plan that minimizes the communication distance based on the fire spread rate model and the location of each substation within the supervision range of each mother station; and obtaining a mother-child station layout method based on the mother station layout plan and the substation layout plan corresponding to each mother station.

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

[0011] v=v max *(1-er *t )+v noise

[0012] Where v is the fire spread speed, v max is the maximum spreading speed, r is the spreading speed constant, t is the time, v noise is noise disturbance.

[0013] In one embodiment, 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.

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

[0015] In one of the embodiments, 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 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 its mother station.

[0016] In one of the embodiments, it also includes: parsing the received fire alarm signal to obtain timestamp information and substation location information; and executing a firefighting task to the corresponding substation location according to the earliest timestamp information.

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

[0018] Each mother station and child station are placed at corresponding positions in the forest according to a pre-set mother-child station layout; the layout is obtained by simulating historical fire data of the forest;

[0019] At the critical temperature, the thermoelectric material of each substation generates electricity and triggers the fixed temperature explosion switch to conduct the circuit to 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 through wireless transmission; the fire alarm signal includes the substation location and the fire detection time;

[0020] Each mother station receives the fire alarm signal sent by each substation and sends it to the monitoring station via satellite or base station;

[0021] 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.

[0022] In one of the embodiments, it also includes: obtaining mountain and forest terrain information, and calculating a mother station layout plan that minimizes the number of mother stations and maximizes forest coverage based on the mountain and forest terrain information and the mother station supervision range; obtaining historical forest fire data, and establishing a fire spread rate model based on the historical fire data; initializing the layout of each substation within the supervision range of each mother station to obtain the location of each substation; calculating a substation layout plan that minimizes the communication distance based on the fire spread rate model and the location of each substation within the supervision range of each mother station; and obtaining a mother-child station layout method based on the mother station layout plan and the substation layout plan corresponding to each mother station.

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

[0024] v=v max *(1-E -r*t )+v noise

[0025] Where v is the fire spread speed, v max is the maximum spreading speed, r is the spreading speed constant, t is the time, v noise A passive mother-child type wildfire situation awareness device based on thermoelectric conversion, the device comprising:

[0026] The above-mentioned passive mother-child type mountain fire situation perception system and method based on thermoelectric conversion can realize efficient fire awareness according to the characteristics of the forest by pre-setting the mother-child station layout mode. After the mother-child station is laid out, no other resource input is required, which can effectively reduce the expenditure of manpower and material resources. The thermoelectric materials and constant temperature blasting switches of the substation provide double fire insurance, which greatly reduces the probability of false alarms. The mother-child stations transmit signals wirelessly. Each mother station provides a bridge for information transmission between the substations and the monitoring station within the coverage area, shortening the signal transmission time, and being able to timely transmit the location information of the substation where the fire occurs and the time of the fire occurrence to the monitoring station. The embodiment of the present invention can transmit early warning signals in a timely manner, effectively realizing early warning before the fire spreads. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of the structure of a passive mother-child type wildfire situation awareness system based on thermoelectric conversion in one embodiment;

[0028] Figure 2 A schematic diagram of the thermoelectric conversion principle in one embodiment;

[0029] Figure 3 This is a schematic diagram of the mother-child station airdrop in one embodiment;

[0030] Figure 4 This is a schematic diagram of the structure of a mother station in an embodiment;

[0031] Figure 5 A schematic diagram of the operation of a passive mother-child type wildfire situation awareness system based on thermoelectric conversion in one embodiment;

[0032] Figure 6 It is a structural schematic diagram of a passive mother-child type wildfire situation awareness system based on thermoelectric conversion in a specific embodiment;

[0033] Figure 7 A schematic diagram of a flow chart of a layout setting of a parent-child station in one embodiment;

[0034] Figure 8 The figure is a flow chart of a passive parent-child wildfire situation perception method based on thermoelectric conversion in one embodiment. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] In one embodiment, Figure 1As shown, a passive mother-child forest fire situation awareness system based on thermoelectric conversion is provided, the system includes multiple mother stations, several child stations corresponding to each mother station, and a monitoring station; each mother station and child station are placed at the corresponding position of the forest according to a pre-set mother-child station layout; the layout is obtained by simulating historical fire data of the forest;

[0037] Each substation includes an induction trigger unit and a signal transmission unit; the induction trigger unit includes thermoelectric materials, batteries and constant temperature explosion switches, which are used to generate electricity using thermoelectric materials at critical temperatures, and trigger the constant temperature explosion switch to conduct the circuit to 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 through wireless transmission; the fire alarm signal includes the substation location and the fire detection time;

[0038] 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 are used to receive the fire alarm signal sent by each substation and send it to the monitoring station via a satellite or base station;

[0039] The monitoring station includes an indication unit, which is used to receive fire alarm signals sent by satellites or base stations, and analyze the fire alarm signals to assist command personnel in making firefighting decisions.

[0040] In the above-mentioned passive mother-child forest fire situation perception system based on thermoelectric conversion, the layout of the mother-child stations can realize efficient fire awareness according to the characteristics of the forest through the pre-set mother-child station layout mode, and no other resource input is required after the layout of the mother-child stations, which can effectively reduce the expenditure of manpower and material resources. The thermoelectric materials and constant temperature blasting switches of the substations provide double fire insurance, which greatly reduces the probability of false alarms. The mother-child stations transmit signals wirelessly, and each mother station provides a bridge for information transmission between the substations and the monitoring station within the coverage area, shortening the signal transmission time, and being able to timely transmit the location information of the substation where the fire occurs and the time of the fire occurrence to the monitoring station. The embodiment of the present invention can transmit early warning signals in a timely manner, effectively realizing early warning before the fire spreads.

[0041] In one embodiment, the thermoelectric material generates electricity when there is a temperature difference between the sun-facing side and the sun-facing side, and stores it in a battery. In this embodiment, the thermoelectric material converts the temperature difference into electrical energy, and the battery stores the electrical energy generated by the thermoelectric material. After the battery stores the electrical energy, it releases the electrical energy at any time according to demand, which not only reduces the need for maintenance and battery replacement, but also enables fire awareness. Figure 6 In the illustrated embodiment, the battery is implemented in the form of a capacitor.

[0042] Specifically, the substation uses thermoelectric materials and batteries to complement each other. The temperature difference between the sun-facing and sun-facing sides of the thermoelectric materials is used to generate electricity and store electricity. When a fire occurs, the drastic temperature change can be used to store electricity again, ensuring that the power reserve can meet the alarm needs. Figure 2 Thermoelectric conversion principle diagram shown in the figure, the thermoelectric conversion system uses the thermoelectric conversion (Seebeck) principle to select specific thermoelectric materials to generate electricity. When the wildfire spreads to the sensing range, the thermoelectric material is heated and generates electricity due to the temperature difference between the inside and outside to provide electricity for the system.

[0043] In one embodiment, the constant temperature explosion switch releases the switch constraint and conducts the circuit when the temperature reaches the critical temperature. In this embodiment, the working principle of the constant temperature explosion switch is mainly based on the temperature sensing material. When the ambient temperature reaches or exceeds its set temperature, the sensing material will undergo physical changes (such as melting, breaking), thereby conducting the circuit. The constant temperature explosion switch is triggered immediately when it reaches the critical temperature, which can ensure that the alarm is realized before the system burns out.

[0044] Specifically, the constant temperature explosion switch adopts a thermosensitive medium glass bottle solution. The glass bottle is located at the bottom of the subsystem. When a fire breaks out outside and the temperature of the bottle reaches the preset temperature, the contents expand and cause the glass bottle to explode. The switch constraint is released, the circuit can be turned on, and the fire signal can be transmitted to the main system.

[0045] The system of the present invention utilizes the temperature resistance limit of the temperature sensing material to distinguish between wildfires and general ambient temperatures. The circuit can only be turned on when the temperature reaches a certain threshold, thereby effectively realizing fire perception. The system also uses thermoelectric conversion materials to generate electrical energy for power supply when a fire is sensed, effectively preventing the switch from being opened and triggering an alarm due to falling, trampling, or biting by wild animals, thereby realizing a double insurance design and avoiding the occurrence of false alarms.

[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 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 its mother station.

[0047] In this embodiment, a GPS module is provided in the single chip microcomputer, and the substation positioning is realized by the GPS module to provide the substation location information.

[0048] In one embodiment, the mother station is solar powered and requires no additional energy input.

[0049] It is understandable that the power supply of the mother station can also be realized by batteries.

[0050] In one embodiment, the substation and the mother station communicate using a signal transmission unit and a signal processing unit based on WIFI6.

[0051] In one embodiment, Figure 3 The schematic diagram of the airdrop of the mother-and-child stations shown in the figure uses drones to airdrop the substations and mother stations into the forest according to the pre-set layout of the substations and mother stations. The substations and mother stations are mounted on corresponding parachutes. In this embodiment, drones are used to airdrop according to the planned routes and the designed deployment density. By parachuting and hanging on trees, sensitive monitoring of mountain fires can be achieved. Due to the large area of ​​the forest and the complex environment, the existing early warning schemes, whether remote sensing monitoring or manual patrols, require high investment costs. The system adopts the passive monitoring principle and does not require other resource input after deployment, which can effectively reduce the expenditure of manpower and material resources. The design cost of the equipment required for deployment per square kilometer according to the preset density is about 1,000 yuan, and the cost is expected to be even lower after mass production. The mother station mainly includes a power supply system and a signal processing system, such as Figure 4 The schematic diagram of the mother station structure shown in the figure uses flexible photovoltaic panels to cover the surface of the parachute to power the device, ensuring all-weather supervision of multiple substations. The parachute structure is used on the outside of the mother station, which can be accurately arranged in the tree layer of the mountain forest while reducing the impact on the natural environment. At the same time, it is convenient to absorb solar energy and achieve green environmental protection. In the embodiment of the present invention, the system is deployed behind the forest and can monitor the fire situation 24 hours a day. At the same time, it adopts a mother-child signal transmission structure, which can send an early warning signal within 30 minutes, and can effectively achieve early warning before the fire expands.

[0052] In a specific embodiment, Figure 5 The working diagram of the passive mother-child forest fire situation awareness system based on thermoelectric conversion is shown in the figure. The specific working process of the overall system is as follows:

[0053] S1. Use drone airdrops to achieve precise mesh deployment of the system in the mountains and forests;

[0054] S2. After deployment, the subsystem charges the battery through the temperature difference of the environment, and the main system works around the clock by complementing the solar energy with the battery;

[0055] S3. When a fire occurs in a certain area, the subsystem senses the temperature change, generates electricity through the thermoelectric conversion device, and transmits the disaster location signal to the main system in combination with the battery power supply;

[0056] S4. The mother system transmits the location information to the monitoring station through satellites or base stations to achieve timely warning of wildfires.

[0057] In this embodiment, if Figure 6The schematic diagram of the structure of the passive mother-child wildfire situation awareness system based on thermoelectric conversion is shown in the figure. The subsystem is mainly composed of an induction 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 usually in a state of no power consumption. The mother system stores energy through photovoltaic panels, monitors the subsystem around the clock, and maintains communication with the monitoring station through satellites, base stations, etc. The mother-child structure makes full use of the performance of communication technology, saves a lot of costs for the deployment of high-precision satellite communication modules, and makes it possible to deploy subsystems more densely and monitor disasters more sensitively.

[0058] The mother and child stations adopt a many-to-one relationship, that is, one mother system and several subsystems are deployed in an area (the specific distribution plan can be obtained by mathematical modeling). The mother and child stations use WIFI6 as the medium for information transmission. If any subsystem alarms in the supervision area covered by the mother system signal, the mother system can receive the signal and notify the forest monitoring station in time. The WIFI6 module can detect the substation signal within a range of more than 200 meters. After receiving the alarm information, the disaster information is transmitted to the monitoring station through the 4G module or satellite communication module, and the monitoring station then realizes the functions of information analysis, disaster location and alarm.

[0059] Compared with existing forest fire alarm technology, this system has more timely fire warning, more accurate warning location and lower operating cost. By controlling the temperature limit of the glass bottle, it is used to distinguish between forest fire and high temperature in the environment (power but no access); by using thermoelectric conversion materials to control power supply, it avoids the situation where the switch is opened and the alarm is triggered due to falling, trampling or biting by wild animals (access but no electricity).

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

[0061] In this embodiment, the fire alarm signal includes the fire detection time and the substation location, where the fire detection time refers to the moment when the substation senses the occurrence of the fire, and the timestamp information is obtained based on this moment. According to the actual needs of the alarm, an embedded system based on stm32 is designed, and various modules are loaded to realize the normal operation of various functions. A terminal alarm and fire point location query software based on VisualBasic6.0 is also designed, which can analyze the alarm information from the monitoring station in the first time, and realize functions such as automatic alarm, visual positioning, and disaster spread trend analysis.

[0062] In one embodiment, Figure 7The flowchart of the mother-and-child station layout setting is shown, and the steps of setting the mother-and-child station layout mode include: obtaining forest terrain information, and calculating the mother station layout plan that minimizes the number of mother stations and maximizes the forest coverage rate based on the forest terrain information and the mother station supervision range; obtaining historical forest fire data, and establishing a fire spread speed model based on the historical fire data; initializing the layout of each substation within the supervision range of each mother station to obtain the position of each substation; calculating the substation layout plan that minimizes the communication distance based on the fire spread speed model and the position of each substation within the supervision range of each mother station; and obtaining the mother-and-child station layout mode based on the mother station layout plan and the substation layout plan corresponding to 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 forest. Due to the limited communication distance, the substation must be deployed within a circle with a radius of 200 meters centered on the mother station to ensure signal transmission. The layout of the substation and mother station needs to consider two issues:

[0064] Question 1: Consider the arrangement of substations within a circle with a radius of 200 meters centered on the mother station.

[0065] Question 2: Consider the circle coverage problem of a circle with a radius of 200 meters in the entire mountain forest.

[0066] For problem 1, the optimization goal is to minimize the distance from any point in the circle to its nearest substation, so that no matter where the fire occurs, it can be detected by the nearby substation 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 so that any fire at any point in the circle can be sensed by the device as quickly as possible", we need to set a suitable fitness function of 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 fire sensing speed. A reasonable metric 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.

[0068] Therefore, the fitness function can be designed as:

[0069] 1. For each point, calculate its distance to multiple sensing devices and take the minimum value.

[0070] 2. Sample multiple points within the entire circle area (or use mathematical methods to calculate the maximum possible distance) and find the maximum of these minimum distances.

[0071] 3. The goal of the fitness function is to minimize this maximum distance, expressed as:

[0072] F=max(min(d(p,s_i)|i=1,2,…,N)|p∈circle)

[0073] Where (d(p, si)) is the distance from point (p) to the sensing device (si), and Circle represents the area of ​​the circle. This formula expresses that: a specific point is determined in the circular area, and the shortest distance from the point to multiple fire sensing devices reaches the maximum value among all possible points in the circle. In practical applications, in order to simplify the calculation, the maximum distance can be approximated by discretizing the circular area, that is, selecting a certain number of representative points.

[0074] Based on the above fitness function, we can design the steps of the genetic algorithm as follows:

[0075] Step 1: Initialize the population: Randomly generate an initial coordinate cluster that meets the boundary conditions.

[0076] Step 2: Evaluate fitness: Calculate the fitness value of each coordinate in the cluster, that is, call the fitness function to determine whether each point is as close to the coordinate as possible.

[0077] Step 3: Select the operation: select the appropriate coordinates according to the fitness value to enter the next round.

[0078] Step 4 Mutation operation: Randomly mutate the selected coordinate individuals to increase the diversity of the coordinate cluster.

[0079] Step 5: Recombination operation: Generate new individuals by combining the features of individuals with different coordinates.

[0080] Step 6 Iterative optimization: Repeat Step 2-5 until the preset number of iterations is reached or the stopping condition is met.

[0081] Step 7 outputs the result: returns the coordinates with the best fitness as the final result.

[0082] For problem 2, the goal is to find out how to use the least number of mother stations with a fixed radius to cover a given irregular forest area, thereby minimizing the number of mother stations and maximizing the forest coverage. This problem can be solved by using a greedy algorithm, where an irregular pentagon is used to simulate the forest area. The specific steps are as follows:

[0083] STEP1 Initialize an empty covered region and an empty detector list.

[0084] STEP 2 Create a grid point set within the polygonal area. These points are used to evaluate which areas are covered.

[0085] STEP 3 enters a loop and continues as long as there are uncovered polygonal areas.

[0086] STEP 4 In each loop, find all uncovered grid points and randomly select one as the center of the new detector.

[0087] STEP 5: Record the position and radius of the new detector into the detector list and update the covered area.

[0088] In one embodiment, the fire spread rate model is:

[0089] v=v max *(1-e -r*t )+v noise

[0090] Where v is the fire spread speed, v max is the maximum spreading speed, r is the spreading speed constant, t is the time, v noise is noise disturbance.

[0091] In this embodiment, the fire spread speed model takes into account the change of the flame spread speed over time. The spread speed of forest fire is related to the fire intensity. In the early stage of the spread, the larger the fire intensity, the faster the spread speed. The fire intensity can be regarded as increasing over time. In addition, the forest fire spread speed has a corresponding upper limit, and it will not continue to increase after reaching a certain speed. Based on this, a fire spread speed model is constructed to simulate the process from the occurrence of the flame to the spread to the substation.

[0092] In one embodiment, Figure 8 As shown, a passive mother-child type wildfire situation awareness method based on thermoelectric conversion is provided, comprising the following steps:

[0093] Step 802, placing each mother station and child station at a corresponding position in the forest according to a pre-set mother-child station layout.

[0094] The layout is obtained by simulating historical forest fire data.

[0095] Step 804, at the critical temperature, the thermoelectric material of each substation generates electricity and triggers the constant temperature explosion switch to conduct the circuit to output a fire alarm instruction, and generates a corresponding fire alarm signal according to the fire alarm instruction and sends it to the corresponding mother station via wireless transmission.

[0096] The fire alarm signal includes the substation location and the fire detection time.

[0097] Step 806: Each mother station receives the fire alarm signal sent by each substation and sends it to the monitoring station via a satellite or base station.

[0098] Step 808: The monitoring station receives the fire alarm signal sent by the satellite or base station, and analyzes the fire alarm signal to assist the command personnel in making firefighting decisions.

[0099] It should be understood that although Figure 8 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 8 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0100] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0101] The above-mentioned embodiments only express several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A passive mother-child forest fire 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 positions in the forest according to a pre-set mother-substation layout; the layout is obtained by simulating historical fire data of the forest; Each substation includes an induction trigger unit and a signal transmission unit; the induction trigger unit includes thermoelectric materials, batteries and constant temperature explosion switches, which are used to generate electricity using thermoelectric materials at critical temperatures, and trigger the constant temperature explosion switch to conduct the circuit to 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 through wireless transmission; the fire alarm signal includes the substation location and the fire perception time; 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 are used to receive the fire alarm signal sent by each substation and send it to the monitoring station via a satellite or base station; The monitoring station includes an indicating unit, which is used to receive fire alarm signals sent by satellites or base stations, and analyze the fire alarm signals to assist command personnel in executing firefighting decisions.

2. The system according to claim 1, characterized in that The steps to set up the parent-child station layout include: Obtain mountain and forest terrain information, and calculate the mother station layout plan that minimizes the number of mother stations and maximizes the mountain and forest coverage rate based on the mountain and forest terrain information and the mother station supervision range; Obtain historical forest fire data and establish a fire spread speed 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 scheme that satisfies the minimum communication distance is calculated based on the fire spread speed model and the locations 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.

3. The system according to claim 1, characterized in that The fire spread speed model is: v=v max *(1-e -r*t )+v noise Where v is the fire spread speed, v max is the maximum spreading speed, r is the spreading speed constant, t is the time, v noise is noise disturbance.

4. The system according to claim 1, characterized in that 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 storage battery.

5. The system according to claim 1, characterized in that The constant temperature blasting switch releases the switch constraint and conducts the circuit when the temperature reaches a critical temperature.

6. The system according to claim 1, characterized in that 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 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 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.

7. The method according to claim 1, characterized in that 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.

8. 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 child station are placed at corresponding positions in the forest according to a pre-set mother-child station layout; the layout is obtained by simulating historical fire data of the forest; At the critical temperature, the thermoelectric material of each substation generates electricity and triggers the fixed temperature explosion switch to conduct the circuit to 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 through wireless transmission; the fire alarm signal includes the substation location and the fire detection time; 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.

9. The method according to claim 8, characterized in that The steps to set up the parent-child station layout include: Obtain mountain and forest terrain information, and calculate the mother station layout plan that minimizes the number of mother stations and maximizes the mountain and forest coverage rate based on the mountain and forest terrain information and the mother station supervision range; Obtain historical forest fire data and establish a fire spread speed 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 scheme that satisfies the minimum communication distance is calculated based on the fire spread speed model and the locations 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.

10. The method according to claim 8, characterized in that The fire spread speed model is: v=v max *(1-e -r*t )+v noise Where v is the fire spread speed, v max is the maximum spreading speed, r is the spreading speed constant, t is the time, v noise is noise disturbance.

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