Flight Path Planning System for Drones Responsible for Fire Management in Open Environments

Abstract

The present invention finds its application, in general, in the field of fire prevention. In particular, the identified solution pertains to the problem of identifying and managing outbreaks or fires that could develop in large, open environments, such as, more precisely, woods and forests. The early detection of the beginnings of a fire is the most effective measure for the containment and extinguishing of fires that develop in forests. In fact, the sooner a fire is identified, the smaller it is; and therefore, the greater the possibilities of taming it, or extinguishing it, or at least of managing its evolution with a view to containment, thus avoiding environmental catastrophes. Ultimately, the invention indicates a system for determining a flight path for a heat- resistant drone, allowing it to be used in missions in which it is pushed to the limit of its heat- resistant characteristics. This is made possible by using an environmental simulation tool that allows for the precise assessment of the risk of damage to the heat-resistant drone while it is on a mission; and this simulation tool is capable of making sufficiently accurate forecasts thanks to the fact that it is fed by information retrieved from a second observation drone, set up for the purpose, and which operates in support of the heat-resistant drone during the planned mission.

Description

1 / 29 Flight Path Planning System for Drones Responsible for Fire Management in Environments OPEN

[0001] This patent application is based on Italian patent application no. IT102021000030197, filed on December 1, 2021, which constitutes an improvement as well as an extension of priority. Technical field of the invention

[0002] The present invention finds application, in general, in the field of fire prevention.

[0003] In particular, the identified solution concerns the problem of identifying and managing fire outbreaks or fires that may develop in large, open environments, such as, more precisely, woods and forests.

[0004] Early detection of the start of a fire is the most effective measure for containing and extinguishing forest fires. In fact, the sooner a fire is identified, the smaller it will be, and therefore the greater the chances of stopping, extinguishing, or at least containing its spread, thus avoiding environmental catastrophes.

[0005] Therefore, every solution that improves the detection and characterization of a fire is a solution that improves fire prevention overall. For this reason, we should never stop researching and developing solutions capable of increasing the speed of fire detection, as well as the accuracy with which that fire is characterized, in order to adopt the best intervention measures to extinguish it. State of the art

[0006] The problem of fires in vast forest areas is a very serious and current problem; it is also a problem whose incidence has been increasing significantly in the world in recent years, and of which public perception is also well known.

[0007] Several factors combine to determine this severe growth. In fact, it can be stated with certainty that the existing forest stock is already very large. Petition 870250085417, dated 09 / 22 / 2025, page 80 / 145 2 / 29 small from the start, due to widespread human encroachment on many territories and, as if that weren't enough, it is destined to shrink even further due to ongoing climate change.

[0008] In particular, the greater frequency and duration of drought periods in some territories, in addition to triggering slow desertification processes, precisely during the hottest and driest periods, makes forests more easily flammable, due to the low humidity retained by wooded environments during these periods.

[0009] Even the significant incidence of arson is perceived as a very serious cause, mainly because it also appears to be subject to a growth dynamic.

[0010] Finally, it can be said that the risk of forest fires is now officially considered, by many nations, as a real emergency, and even a serious one.

[0011] Until now, in terms of prevention, the response to this problem has focused mainly on educational measures. At various levels of communication, efforts have been made to raise awareness among people who frequent forests so that they do not adopt risky behaviors. This action is certainly effective for all people who frequent forests and natural areas in general, with a spirit of interest and respect for nature, and who are concerned about its protection, but it is much less so for another segment of the population with less environmental sensitivity, to the point of being totally ineffective in relation to those responsible for starting arson fires.

[0012] Once a fire develops, the measures required to extinguish it become extremely complex, requiring the use of many resources and many people.

[0013] The use of airplanes or helicopters capable of dropping water on the fire, as well as other substances that reduce the flammability of plants, would allow for effective intervention if interventions could be implemented when the fire was not yet too extensive; but unfortunately, often these interventions cannot be put into practice with the necessary timeliness, as the means that perform this service (the most common being aircraft produced by the company) Petition 870250085417, dated 09 / 22 / 2025, page 81 / 145 3 / 29 Canadian Canadair) are very expensive and their number is limited, so they often have to arrive from places far from the fire, further delaying intervention. Therefore, it is common for forest fires to become a real environmental catastrophe within a few days.

[0014] In some cases, then, wind and general weather conditions, for example, in circumstances where the weather has been dry for several days, cause fires in wooded areas to develop very rapidly; and when their dimensions become very large, it becomes very difficult to contain them with the interventions of firefighters (however numerous and well-equipped they may be) or with the use of airplanes or helicopters that drop water from above: in many cases, when the forests are sufficiently close to the coast, this is saltwater taken directly from the sea. In these cases, the fires last for several days and destroy tens or hundreds of thousands of plants, in addition to compromising the regrowth of plants for decades when the extinction is done through the dispersal of saltwater from the sea.

[0015] The only way to contain the seriousness of the situation related to forest fires is to detect their start earlier.

[0016] Unfortunately, however, the extent of the wooded areas makes any kind of punctual and detailed monitoring particularly difficult. The decision to address the problem with the deployment of massive monitoring infrastructures therefore seems inevitable; in fact, it is unthinkable to monitor an area as vast as those that characterize the woods without adequate infrastructural supervision, since there is usually no network of paths that allow for the inspection of woods and forests in any other way.

[0017] One method, which appears promising, involves creating a number of conveniently equipped monitoring stations to support continuous surveillance of a fairly large area around this station: an order of magnitude of the distance to which this type of monitoring station can extend its surveillance is several kilometers. This order of magnitude of distance should obviously be understood as a purely illustrative figure and may vary, up to Petition 870250085417, dated 09 / 22 / 2025, page 82 / 145 4 / 29 very much so, depending on individual cases (for example, depending on the terrain's orography) and the technologies used at the station itself.

[0018] However, this approach is not yet widespread due to its costs; in fact, these monitoring stations require power supplies, the presence of equipped personnel, and much more.

[0019] There are some projects, currently in the proposal stage, or limited to demonstration facilities, which foresee: The construction of a tower or lattice structure, which allows for an elevated observation point; it also typically acts as a telecommunications station to manage the interaction between all sensors and systems present in the monitoring infrastructure as a whole, as well as communication with other control stations; The distribution, within the forest, of a network of sensors of various types, suitable for transmitting data correlated with the presence or risk of fire to the observation station; The use of a fleet of drones with various specializations, suitable for performing specific tasks, and capable of moving to reach various points in the monitored forest.

[0020] In general, while it is not possible to monitor a large area of ​​several square kilometers with a high level of detail, then surveillance should be configured anticipating different levels of detail.

[0021] Therefore, broad initial surveillance should be foreseen, capable of identifying situations with a probability of fire; while more detailed inspection levels should be able to be activated only after the selection of specific, and possibly very delimited, areas in which detailed monitoring is concentrated.

[0022] For the purposes of the present invention, it is assumed that, through the monitoring stations of the indicated type, large-scale surveillance is implemented, capable of alerting in real time situations of fire risk, or suspected fire, and, following these alerts, the problem of activation is triggered. Petition 870250085417, dated 09 / 22 / 2025, page 83 / 145 5 / 29 targeted surveillance measures, or initial measures to contain the potential start of a fire, with interventions on site.

[0023] It is clear that countless configurations of monitoring stations are possible with different costs and performances, where technological resources are more or less abundant and differ in the quality of their performance.

[0024] Furthermore, in addition to the elements mentioned above (observation tower, sensor network and drone fleet), which constitute equipment that can be considered basic for many proposed solutions, monitoring stations can also include plants and systems of other types, especially to support any interventions to contain detected fires; for example: basins with water reserves, cisterns with substances useful for fire treatment, equipment to equip rescue teams, power generation systems for the needs of the station itself and all systems related to it, and much more.

[0025] Consequently, the variety of equipment that can be assembled in such stations generates an almost indefinable variety of possible different configurations for them.

[0026] In the context of this description, we will not go into the huge variety of configurations that can be designed to define the tasks and objectives of monitoring stations; instead, we focus on a specific problem that, depending on how it is solved, can positively or negatively affect the performance of a monitoring station as a whole, in a significant number of different configurations.

[0027] The problem addressed is to reach, as quickly as possible and as closely as possible, using a drone, the points where a fire is developing.

[0028] Speed ​​is essential, because the size and therefore the potential uncontrollability of a fire usually increases very quickly.

[0029] Proximity is also very important for obtaining accurate information (in the case of drones with observation tasks), but also for being able to implement Petition 870250085417, dated 09 / 22 / 2025, page 84 / 145 6 / 29 targeted containment measures in the areas where they can be truly effective.

[0030] A trivial but useful example to illustrate the above concepts is that of a drone carrying containers of fire extinguishing substances to be dropped on a fire to put it out, or to be dropped along the front of a fire to prevent its spread.

[0031] These containers are a few decimeters in size and, when thrown into a small fire, extending over a few meters, they spread their contents and are often able to extinguish a small fire.

[0032] If, on the other hand, they are to be deployed for the purpose of creating a non-combustible zone to stop the advance of an expanding fire front, they must create a continuous belt, without parts containing combustible material that would allow the advancing fire front to pierce the containment front.

[0033] Even imagining that a drone can carry a certain number of such extinguishing containers, it is clear that to be effective, this drone must arrive at the scene before the fire becomes too large. Furthermore, for the intervention to be effective, the containers must be dropped with good precision, so as to cover the entire intended area, to avoid landing on a fire that could eventually spread, rendering the extinguishing attempt futile. It is clear that if the containers are dropped from above, from a certain distance, the landing precision may not be sufficient. Consequently, the launching drone in the example, in addition to having to arrive early, must be able to fly very close to the fire, in environmental contexts with temperatures at the limit of its resistance specifications.

[0034] Once the flames are extinguished or contained, it often happens that after a few hours, even at night, small outbreaks reappear. This problem is widespread, and that is why it is necessary to monitor the territory closely and continuously, maintaining vigilance even when the fire is apparently extinguished, in order to intervene quickly to contain any resurgence of the flames at the root. Petition 870250085417, dated 09 / 22 / 2025, p. 85 / 145 7 / 29

[0035] All the above observations make it clear that the use of drones is a key factor both in ensuring good monitoring and in implementing early interventions. Furthermore, it is clear that the number of drones available at each monitoring station is also a critical factor for the effectiveness of monitoring and intervention. It is clear that with some drones it is not possible to monitor large forest areas frequently and closely enough (to identify even small fire outbreaks). Similarly, too few drones are unable to dispense sufficient quantities of extinguishing substances to contain the development of a fire.If we add to this the fact that many actions carried out by drones are based on highly specialized functions, it can be concluded that the fleet of drones that a monitoring station must have at its disposal must be extremely large (the larger the fleet of drones, the more effective a monitoring station can be in fire prevention and management).

[0036] One way to try to contain the number of drones without accepting overly penalizing compromises regarding the effectiveness of both monitoring and intervention is to have drones capable of performing a plurality of functions. The latter approach (i.e., resorting to universal drones capable of performing various functions in a specialized way) is certainly viable in theory; in practice, it involves numerous technical difficulties that considerably limit its potential. Many of these challenges relate to the fact that different functions require different physical performances; for example, some functions require agility, others require the ability to fly in any high-temperature environment, other functions require payload capacity, and so on.

[0037] If the intention is to implement a monitoring system for large areas of woods and forests, the state of the art certainly provides for several technologies. The technologies described above are, in fact, available and can be used both to carry out highly effective monitoring and to implement fire-fighting actions, or at least to assist in the implementation of fire-fighting actions. Petition 870250085417, dated 09 / 22 / 2025, p. 86 / 145 8 / 29

[0038] The state of the art, at the system level, for the application identified in this patent is also represented by US 2012 / 0261144 A1 [“FIRE MANAGEMENT SYSTEM” - Vian, JL (US), Saad EW (US), on behalf of BOEING - October 18, 2012].

[0039] This document describes a highly complex system that utilizes numerous technologies to create a true fire suppression system for woodlands and forests.

[0040] The system proposed in US 2012 / 0261144 A1 comprises flying and ground vehicles, with autonomous pilot and steering, various sensors (both video and other types of sensors) that allow the detection of the presence of fires, a control tower equipped with appropriate calculation means, which allows the implementation of coordination and control functions appropriate to the interventions that are necessary to prevent and combat the development of fires, and which takes into account environmental conditions to predict the development of any fires.

[0041] The problem with systems like the one proposed in US 2012 / 0261144 A1 can be traced, in short, to the potential complications of using unlimited resources, which consequently raises questions of high costs. In fact, it is quite intuitive to state that, given unlimited resources, it is possible to deal with fire threats at a theoretical level, but without any guarantee of success for the many problems encountered in forests. However, given that the availability of unlimited resources and their effectiveness in any situation is a purely theoretical hypothesis, it is clearly necessary to accept a compromise that assumes a limitation of resources and accepts the risk of not being able to manage all fires, without prejudice to achieving ideal intervention effectiveness.

[0042] Regardless of verifying the system's ideal efficiency, the compromise indicated in US 2012 / 0261144 A1 remains highly unbalanced with very high costs, so much so that, more than ten years after Boeing's proposal, fire management systems like the one indicated in US 2012 / 0261144 A1 are not widely used, despite the fact that the phenomenon of forest fires is perceived as a problem of growing importance, considered absolutely urgent and whose solution is now unavoidable. Petition 870250085417, dated 09 / 22 / 2025, page 87 / 145 9 / 29

[0043] To make these solutions viable, it is therefore necessary to invent as many devices as possible that introduce strong optimizations, otherwise it will be practically impossible to propose such systems for managing fires in woods and forests. Purpose and summary of the invention

[0044] The main purpose of the present invention is to seek strong optimizations in the use of drones, which, as seen, are essential tools both in the monitoring phase and in the early intervention phase in case of fire.

[0045] Therefore, the invention aims to indicate a flight control system for multifunctional drones to be used in the fire monitoring station; and this control must ensure that the flight path is optimized in relation to the function assigned to each drone, taking into account that: Each drone has a heat resistance that can be defined in terms of the maximum ambient temperature in which it can fly, and in terms of the time that drone can withstand certain temperatures. Each drone offers certain performance levels in terms of minimum and maximum flight speed and in terms of the maximum payload it can carry. Each drone has a certain flight range as a function of flight speed and payload.

[0046] Of particular interest are flight paths that allow a specific drone to reach areas affected by the risk of developing fires as quickly as possible and as close as possible to the fire itself, remaining there for the time necessary to accomplish its mission and returning undamaged.

[0047] In fact, the effectiveness of the mission depends heavily on the precision with which the drones can perform the task assigned to them, and for that they must get as close as possible to the fire.

[0048] The technical problem associated with achieving this objective is further compounded by the fact that, for reasons of resource optimization (essential for being able to realistically propose such systems), it is necessary to resort to the use of multi-functional drones, i.e., drones that can be assigned to different tasks, depending on the case. Petition 870250085417, dated 09 / 22 / 2025, page 88 / 145 10 / 29

[0049] Flight path optimization must be able to be updated in real time even when the drone is already flying, as environmental conditions can change rapidly, or because environmental information may also be updated later than when the drone needs to take off to reach the fire in a timely manner.

[0050] As already mentioned, optimization must also take into account the task assigned to the drone, to avoid missions where the risks of damage caused by drones are not justified by the results that the mission may bring, or, conversely, one may choose to sacrifice a drone, for example by accepting that it may burn during the mission, as long as it manages to perform a very important task before its destruction.

[0051] It is assumed that all the hypotheses presented, and all the projects proposed, for forest fire monitoring stations cannot disregard the fact that they are significantly computerized stations. In fact, their operation depends on their ability to acquire and interpret the data stream to these stations. Among this data, climatic and environmental data are obviously very relevant, and therefore it will be assumed that climatic and environmental data are available and that this data can be processed with adequate, very powerful and state-of-the-art computing means.

[0052] The stated objectives can be achieved through a flight path planning system of a plurality of multi-functional drones, each of which can be equipped with at least two different payloads; This flight path planning system is equipped with calculation tools configured to determine safe flight routes, and with devices provided to each drone belonging to the aforementioned plurality of multi-functional drones, each of which is associated with its own information sheet specifying: The maximum endurance time of the drone itself at various temperatures, with its different payloads; in other words, how long the drone can function correctly when operating at high temperatures. the minimum and maximum flight speeds according to the payload with which it is equipped; Petition 870250085417, dated 09 / 22 / 2025, p. 89 / 145 11 / 29 The flight range, that is, the energy or fuel consumption according to the payload with which it is equipped, and among the aforementioned devices supplied for each drone belonging to the aforementioned pluralities of multifunctional drones are included (among other things): means of two-way radio communication between the aforementioned multi-role mission drone and at least one fixed radio station; Two-way radio communication means between each multi-functional drone and another multi-functional drone (where the aforementioned communication means indicated in points a) and b) may coincide); at least one temperature sensor or thermal imager. adequate memory means to memorize at least one flight path; adequate geolocation means to detect the position and instantaneous speed of the drone itself, to verify, during flight, even if approximately, whether the flight path being followed is compatible with at least one memorized flight path; The aforementioned system for determining safe flight paths for multi-functional drones also includes an environmental model that represents, in computer format, the physical environment containing the planned flight paths for said plurality of multi-functional drones.

[0053] All the features listed above, although not widely disseminated in actually implemented systems, are substantially known techniques. What characterizes the invention is the possibility of exploiting the environmental model in a particularly efficient way, significantly improving the accuracy with which the model itself can predict real environmental conditions in which the drone should fly.

[0054] Therefore, the drone flight path planning system, in the case of missions that require getting as close as possible to the fire, is characterized by the fact that it also includes a second observation drone equipped with temperature sensors, a thermal imaging camera, and sensors to acquire wind speed and direction. Petition 870250085417, dated 09 / 22 / 2025, pp. 90 / 145 12 / 29

[0055] Finally, after further analysis, the drone flight path planning system according to the invention is actually configured to simultaneously control the flight of pairs of drones: a first mission drone that flies close to the fire, and a second observation drone with reliable data acquisition functions, capable of determining the boundary conditions to effectively use the aforementioned environmental model.

[0056] The route of the aforementioned second observation drone is planned to bring the drone to the area where the fire is present, but without getting as close as possible to it, so as to always be at safe temperatures, with essentially zero risk of being damaged by the fire.

[0057] The drone flight path planning system according to the invention is therefore also characterized by comprising suitable calculation means also arranged to determine said safe flight paths for said mission drone by processing said paths through their simulation within an environmental model, which in turn is characterized by the fact that: The temperature values ​​of all points in the aforementioned physical environment are updated, essentially in real time, and the aforementioned environmental model is suitable for simulating the evolution of said temperature values ​​in the near future, in the event of a fire developing in said physical environment, and said simulations are performed by means of a simulation program, executed by means of said calculation means, and configured to process some input data, among which are at least the following data: a. temperature data, also detected by the aforementioned thermal imaging camera with which the aforementioned second observation drone is equipped, and which is positioned at a safe height in relation to a possible fire, b. data on wind speed and direction, detected by special sensors with which the aforementioned second observation drone is equipped; c. data describing the vegetation present in the aforementioned environment Petition 870250085417, dated 09 / 22 / 2025, pp. 91 / 145 13 / 29 represented by the aforementioned environmental model, in which the aforementioned descriptive data of the vegetation includes a parameter that expresses the combustibility of the described vegetation.

[0058] This process of the aforementioned input data, along with other information including data detected directly by the mission drone itself, allows for the evaluation, essentially in real time (the real-time approximation obviously depends on the computing power involved), of the evolution of the fire and consequently the temperatures in the space where each multi-functional drone is flying (obviously when it is on a mission) according to the path it is following.

[0059] This therefore allows for recalculating and updating, essentially in real time, the best path to follow, possibly also modifying the intervention strategy to be adopted, to adapt it to the evolution of the situation.

[0060] The main advantage over known systems (although not implemented in real applications, for the reasons explained above) lies in the greater precision with which the environmental model allows predicting the evolution of the environmental situation; in fact, no planning system provides for the simultaneous planning of the routes of a pair of drones, one of which (the observation drone) follows a safe and simpler route to plan, as it does not need to get very close to the fire, and which is essentially dedicated to collecting very precise and significant measurements. The measurements collected by the aforementioned second observation drone are, in fact, truly precise and significant precisely because they were collected close to the route followed by the other drone (i.e., the drone that must carry out the mission near the fire), which must fly in an environment that must be known as much as possible.

[0061] It is observed, and underlined, that the characterizing part of the flight planning system for a drone on a mission near a fire, according to the teachings of the invention, benefits from the presence of an additional drone, and relates to some functional characteristics present in various elements of a more complex system, created to prevent and contain the development of devastating fires in woods and forests. Petition 870250085417, dated 09 / 22 / 2025, p. 92 / 145 14 / 29

[0062] The system involves the construction of a number of monitoring stations scattered throughout the forest area to be monitored. This system, comprising monitoring stations that also act as a support and control station for a fleet of drones, can be designed according to numerous variants, but, to comply with the teachings of the present invention, it must obviously comprise at least a pair of drones with the characteristics previously indicated, and adequate computing means to keep an environmental model updated, capable of describing the evolution of the temperature field in a given area, even when affected by a fire.

[0063] The invention allows the calculation of flight paths in such a way that a drone with known heat resistance characteristics can enter areas where there are very high temperatures, but ensuring that the drone's stay in these areas remains within the limits in which the drone is able to withstand or, in any case, function, according to an operational program that is established as necessary to manage a specific fire case.

[0064] In this way, the main requirement for which the invention was conceived is fulfilled, because the proposed solution introduces an important optimization of the overall system, since the cost-benefit trade-off introduced by the fire prevention system is substantially improved.

[0065] This invention also has other advantages, which will become more apparent from the following description, from some examples of practical embodiments that illustrate more details, from the appended claims that form an integral part of the present description, and from the attached Figure 1 which shows a simplified overview of the teachings of the invention in an implementation context. Detailed description

[0066] The flight planning system of a drone that needs to perform a mission near a fire, made according to the teachings of the present invention, makes use of some known technologies that allow obtaining general performances of interest. Petition 870250085417, dated 09 / 22 / 2025, page 93 / 145 15 / 29

[0067] One of the first technologies that can be accessed, critical to implementing this invention, is drone technology. The supply of these vehicles is extremely vast and constantly evolving, given that they are objects that can be used for a very large number of applications. In particular, there are several drones that are more or less heat-resistant, with extremely interesting characteristics that allow them to reach points even at very high temperatures, as there are heat-protective treatments that allow you to protect generic drones to be able to use them at temperatures higher than those for which they were initially designed. Some solutions are certainly interesting for carrying out some embodiments of the present invention.

[0068] In any case, regardless of the heat resistance characteristics, each drone can theoretically be managed by planning its own flight according to the teachings of the present invention in order to make the flight safe even in environments characterized by potentially dangerous temperature conditions. Importantly, for the purpose of implementing the invention, it is possible to characterize with sufficient precision the maximum temperatures at which the drones in question can operate, also specifying the maximum time periods for which they can remain exposed to these temperatures.

[0069] Applications involving missions in environments dangerous to humans are some of the typical applications for which drone technology is designed. Therefore, it is not surprising that there are some drones designed to operate in high-temperature environments; in these cases, these drones are usually supplied with specific technical data sheets that indicate exactly the heat resistance limits within which their operation is guaranteed.

[0070] Such heat-resistant drones can evidently be used to implement the teachings of the present invention.

[0071] The invention, however, can also be implemented with drones designed for general applications, possibly applied with suitable paints or heat-protective substances, or equipped with a heat-resistant coating effective in heat protection. Petition 870250085417, dated 09 / 22 / 2025, pp. 94 / 145 16 / 29

[0072] Obviously, in addition to drones for general applications, these protective measures can also be adopted in drones specifically designed for applications in fire contexts, further improving the heat resistance characteristics of the latter.

[0073] As an example, and in support of the statement that it is possible to improve the heat resistance performance of a drone, a substance produced by the American company “GelTech Solutions” based in Florida is mentioned, which provides some heat-protective substances (see also https: / / geltechsolutions.com / fireice / product / fireice-561 / ), including an extremely effective gel that can be sprayed on the external surfaces of a drone, preserving it for a certain time from overheating, even if directly hit by a flame.

[0074] Other interesting solutions for protecting generic drones to be used in flight missions in high-temperature contexts are offered by the Italian company “Flame Spray” (see also https: / / www.flamespray.org / it / tecnologie / cold-spray / ), which also specializes in supplying substances and materials to protect any type of object from excessive overheating.

[0075] In conclusion, it can be said that the known technique offers several solutions for the production of heat-resistant drones, suitable for the implementation of the present invention.

[0076] Of course, if generic drones are used, which are subsequently treated to increase their heat resistance performance, it is necessary to provide a characterization of the performance obtained through such treatments. If this characterization is not easily inferred from the technical data sheets of the products used, it is always possible to arrive at an adequate characterization for the implementation of the invention through a measurement procedure carried out experimentally.

[0077] In fact, if heat resistance is an important characteristic for planning flight missions that penetrate deep into the area affected by the fire, from a strictly functional point of view for implementing the invention, the Petition 870250085417, dated 09 / 22 / 2025, pp. 95 / 145 17 / 29 which is binding is the availability of a quantitative characterization of actual heat resistance performance.

[0078] Another important known technology that can be conveniently used in the implementations of the present invention is given by environmental simulation techniques.

[0079] In fact, there are very reliable weather forecasting models that work on a mesoscale and can be configured even in very small spatial definitions, so that they can very accurately represent the temperature, pressure and air speed fields in the three-dimensional space where a drone intends to fly.

[0080] An example of this type of simulation tool is known by the acronym WRF (Weather Research and Forecasting), which is also an “open source” tool. The WRF model requires the input of initial and limit information of a meteorological type (such as wind, temperature, humidity and geopotential) and, through simulations, whose spatial and temporal definition is configurable, produces meteorological values ​​within a three-dimensional space and, in particular, in the space to which a heat-resistant drone is intended to be sent on a mission.

[0081] There are also numerous fire development simulation models capable of predicting the evolution of a fire from meteorological and environmental data. Meteorological data can be those produced by a meteorological model (such as the WRF model), while other environmental data describe the environment in which the fire develops, and include information on the vegetative state of plants and their predispositions to burn.

[0082] The combination of two models, namely the meteorological model and the fire development model, allows for the determination, with excellent accuracy, of the temperature, pressure, and air velocity fields in the space where drones involved in fire management must fly.

[0083] It should be noted that the WRF meteorological model was designed to work in conjunction with the fire evolution simulation program called Fire, giving rise to a particularly accurate integrated WRF-Fire tool, as it takes Petition 870250085417, dated 09 / 22 / 2025, page 96 / 145 18 / 29 also takes into account, with extreme precision, the effect of the fire on meteorological data, since the development of a fire obviously has effects on temperature and on the generation of thermal air currents.

[0084] Finally, it can be stated that, starting from boundary information at an initial instant, it is theoretically and practically possible to reconstruct an accurate description of the temperature fields relating to the space in which a heat-resistant drone must enter to complete a mission associated with fire management. Furthermore, the accuracy of the simulation program, if performed with very rigorous definitions (something limited only by the available computing power), also allows estimating the thermal currents that are generated in the space affected by a fire.

[0085] It is clear that the accuracy of these models depends significantly on the accuracy of the input data, the boundary conditions and the size of the space in which the most accurate characterization must be obtained: and it is precisely with reference to these latter aspects that the invention offers an essential and decisive contribution to the practical applicability of these models.

[0086] In fact, without data related to boundary conditions, which refer to a space very close to the points where the simulation must be accurate, simulation technology does not offer the performance that is needed to achieve effective applicability in real-world cases.

[0087] Many environmental research projects utilize and develop “WRFFire” tools, which, to this day, are considered the most complete software for this type of simulation. Furthermore, being open-source software tools, they lend themselves to continuous evolution, updates, and adaptations to a wide variety of applications. Therefore, simulation tools based on WRF-Fire technologies, and their evolutions (for which the acronym WRF-SFIRE, i.e., Spread Fire, is also frequently used), appear, at present, to be the preferred tool for carrying out the environmental simulation model necessary for the implementation of the present invention.

[0088] For more information on WRF-Fire / WRF-SFIRE technology, please visit the organization's official website (see https: / / wiki.openwfm.org / wiki / WRF-Fire) Petition 870250085417, dated 09 / 22 / 2025, page 97 / 145 19 / 29

[0089] Finally, it can be concluded that the simulation tools necessary for the implementation of the invention can be considered known tools, but as they are tools of very specialized use, they can only be used by figures with a high degree of specialization.

[0090] Therefore, given the degree of specialization required to use these simulation tools, all the possibilities for applying these modeling tools have not yet been explored and, in particular, there are no state-of-the-art applications aimed at planning a drone flight path.

[0091] To conclude a sufficient feasibility analysis of the invention, it is necessary to mention other technologies capable of detecting the other essential data for implementing the flight planning system of a heat-resistant drone in accordance with the teachings of the invention: in particular, suitable technologies are needed to find the aforementioned meteorological data, in addition to data on the vegetative state of plants that are present in the area affected by a fire (or by an outbreak or threat of fire).

[0092] The solution indicated in the present invention involves associating the mission of the heat-resistant drone, i.e., the mission drone itself (whose system calculates the ideal flight path in relation to pre-established objectives), with a support mission conducted by means of a second drone, called an observation drone. This second observation drone is equipped to detect essential data so that the route of the heat-resistant mission drone (which plays the most important and active part of the fire management mission) can be better planned. In particular, said observation drone provides and supplements information on boundary conditions, which are necessary to use any mesoscale meteorological model, and collects data on the vegetative state of plants affected by the spread of the fire.

[0093] The route of this observation drone was designed to fly near the fire, but not inside the fire area, i.e., under safe conditions and normally at an ideal altitude to observe the evolution of a fire from above (and not from within). In fact, this observation drone is substantially positioned on the edge of the Petition 870250085417, dated 09 / 22 / 2025, page 98 / 145 20 / 29 three-dimensional space that must be simulated, that is, in an ideal position for measuring the boundary data that all simulation models need in order to implement reliable simulations.

[0094] Furthermore, using suitable thermal imaging cameras, the aforementioned observation drone is suitable for detecting a map of ground temperatures, i.e., the temperature of the outer surfaces of vegetation that can be seen from above, in order to provide the model with additional information to refine its simulations.

[0095] Finally, again with sensors mounted on these observation drones, it is possible to detect some characteristics about the vegetative state of the plants and their degree of dryness.

[0096] This information about vegetative states can also be acquired using known technologies based on spectral analyses performed with active sensors that irradiate the underlying vegetation with radiation at various wavelengths and measure the intensity of the reflected radiation. We will not go into these technologies for determining the vegetative state of plants, but it is important to emphasize that these technologies are available, as their development and improvement are carried out primarily for applications in mechanized agriculture, where the automatic detection of the state of a crop is essential to calibrate the treatments to be applied to the plants or, more simply, to regulate irrigation in an optimized way.

[0097] By combining data collected by sensors (which can exhibit significant variability over time, even in the short term) with maps expressing the type of vegetation present in a forest (which, on the other hand, is quite stable information over time), it is certainly possible to maintain an updated map in which each point of the forest is assigned a flammability index, expressive of the real flammability of the forest point by point.

[0098] Consequently, an appropriate combined environmental model, such as those mentioned above, can very well simulate flame propagation under any contingent circumstance. Petition 870250085417, dated 09 / 22 / 2025, page 99 / 145 21 / 29

[0099] It should be noted that these maps, which express the type of vegetation, obviously do not need to be detected in real time, as they represent relatively stable information; they can therefore be considered as available information, and can be pre-established maps kept up-to-date through cartographic processes carried out regularly, even with fairly slow detection rates, and outside of missions activated in reaction to the occurrence of a fire risk (for example, a map of the plants present in a forest, updated a few days before a mission, is certainly a reliable map, certainly usable in the context of such a mission).

[0100] Finally, it should not be forgotten that the invention makes sense if it is possible to quickly identify areas at risk of triggering a fire, or areas in which a fire is developing.

[0101] Obviously, this preliminary analysis is crucial in fire prevention, and the better it is conducted, the more it is possible to exploit the teachings of the present invention in the ideal way.

[0102] These analyses can now be carried out in various ways and at various levels of surveillance: starting from observation processes carried out from elevated positions at the top of the observation station tower, as foreseen in the preferred implementation of the present invention, or continuing with observations made at high altitudes by special drones, up to analyses based on data from possible sensors scattered in the forest, and without neglecting the possibilities offered by artificial intelligence-based analysis techniques, especially to predict possible malicious behavior of people who can be identified semi-automatically and in various ways.

[0103] This part of the analysis is not the subject of the present invention. For the purposes of this description, it suffices to state that it is possible to implement analysis strategies, based on data collection, that allow the selection of areas of a forest in which it is advisable to plan the mission of a heat-resistant drone for the performance of appropriate tasks of prevention or early containment of fires. Petition 870250085417, dated 09 / 22 / 2025, pages 100 / 145 22 / 29

[0104] The flight path planning system of a drone, used in missions that require it to get as close as possible to a fire, is therefore a very articulated system that provides for the cooperation of a plurality of technologies that, although in the state of the art, are very advanced and must be integrated in an innovative way.

[0105] Planning flight routes may seem like just a detail when faced with the complexity of managing fires in woods and forests, but it is a very important detail from a qualitative point of view, allowing for the optimization of interventions, enabling the application of ideal management to individual cases, based on very precise information, and also allowing for targeted and surgical physical interventions in the fire.

[0106] In Figure 1, a broad context for applying the teachings of the invention is shown: in the figure, it is possible to visually appreciate some (not all) of the numerous innovative devices that can be used to implement the invention.

[0107] In Figure 1, number 200 shows a fire spreading at a certain distance from an observation station, indicated by number 110, and located in an elevated position, positioned on top of a tower indicated by number 111.

[0108] The aforementioned fire 200, in the generic case, occurs at such a distance that it is not possible to observe it in detail from observation station 110, from where, normally, it is only possible to identify some indications that may raise suspicion that there is a fire threat. Therefore, the observation, to be effective, must make use of appropriate means to approach fire 200 and find detailed information: and according to the teachings of the invention, it is foreseen that a drone will be sent on a mission to carry out in-depth observations taken near the fire itself. The teachings of the invention foresee that the mission will involve two drones: potentially two drones of the same type, but equipped with different equipment.

[0109] The drone indicated in Figure 1 with the number 130 refers to a mission drone, because it is equipped to perform functions that require reaching the most Petition 870250085417, dated 09 / 22 / 2025, pp. 101 / 145 23 / 29 as close as possible to the fire, entering areas with potentially very high temperatures.

[0110] The aforementioned mission drone 130 is characterized by the fact that its thermal resistance characteristics must be known, that is, the maximum temperatures at which it can operate, and the times for which it can remain operating in areas at these maximum temperatures without suffering damage. The aforementioned mission drone 130 is the drone whose ideal trajectory must be calculated, to bring it as close as possible to the flames of the fire 200. Generally, these mission drones are equipped with various instruments, which can be classified into two types.

[0111] The number 131 indicates tools capable of performing physical interventions in the fire 200: normally, these tools are dispensers of substances with extinguishing properties.

[0112] The number 132, on the other hand, indicates research instruments. Among these tools, the following stand out: cameras capable of acquiring detailed images to document specific parts of the fire (or the beginning of the fire) and environmental sensors to measure temperatures, pressures and any air currents.

[0113] The aforementioned mission 130 drone must also be able to acquire its own position, to verify that it is following the planned trajectory, as well as georeference the acquired surveys.

[0114] In some of the preferred embodiments, the Mission 130 drone is configured with arrangements that increase its heat resistance properties (ranging from the use of specific coatings to the application of suitable paints designed for this purpose and which were mentioned in the first part of this description).

[0115] As mentioned several times, the trajectory of the mission 130 drone must be calculated with the highest possible precision to explore the drone at the limit of its performance, and this calculation uses a model that simulates the temperature field of the environment in which the drone is immersed. The simulation requires measured limit data and other continuous measurements to Petition 870250085417, dated 09 / 22 / 2025, pp. 102 / 145 24 / 29 feedback and verification, in order to refine the simulated values, since the evolution of fires is usually very rapid.

[0116] The problem of ensuring the availability of such boundary information, as well as feedback information on the simulation results, is solved by providing that this mission is also accompanied by a second drone equipped for this purpose: this second drone is called the observation drone and is indicated in Figure 1 with the number 120. The observation drone 120 is therefore equipped with suitable instrumentation to detect data to define the boundary conditions to be used in the simulations and to make other useful observations to verify and possibly correct the values ​​calculated by the simulation.

[0117] As mentioned, the aforementioned observation drone 120 comprises an arsenal of environmental sensors and cameras, including a thermal camera sensitive to infrared radiation. In Figure 1, the number 121 indicates a “payload” with which the drone 120 must be equipped when used as an observation drone. In particular, the “payload” 121 of the drone 120 is generally different from the “payload” of the mission drone 130.In fact, the 120 observation drone does not require devices to dispense extinguishing substances, nor even observation devices suitable for operating in very high temperatures; instead, it must be equipped to collect, with the best possible reliability, all the limit data that serve as input for the environmental simulation model, so that it can generate reliable forecast data regarding the precise evolution of temperatures in the environment that is the mission's theater; this equipment must have sensors dedicated to measuring the speed and direction of air currents, since this data is fundamental in all environmental models.

[0118] Figure 1 also shows how said drones, for observation (120) and mission (130), are connected by suitable communication channels. The communication network to which the two drones are connected is necessary to implement the invention, but it can be based on different architectures, which gives rise to many variants of the invention. Figure 1, however, highlights two links that can represent an essential and efficient configuration. Petition 870250085417, dated 09 / 22 / 2025, pp. 103 / 145 25 / 29

[0119] The mission drone 130, which has to fly in many critical environments, must be equipped with systems that are as simple and lightweight as possible, therefore it maintains a local and short-range connection only with the observation drone 120, this connection is indicated in Figure 1 with the number 323.

[0120] The aforementioned connection 323 is the simplest and smallest possible, given that the observation drone 120 travels relatively close to the heat-resistant drone 130, with the sole precaution of not entering the hottest areas of the fire.

[0121] Communication with observation station 110, which in fact also functions as a real control station, is ensured by the radio connection, indicated in Figure 1 with the number 321, which keeps observation drone 120 directly connected to observation station 110.

[0122] The fact that mission drones are always connected to control station 110 (directly or indirectly) is an important feature of the invention, since the critical route of the heat-resistant mission drone 130 must be constantly monitored and possibly corrected according to the observations acquired and according to the evolution of the fire.

[0123] Well, the fact that the invention's teachings foresee that critical missions should be conducted with a pair of drones allows, among other things, guaranteeing absolutely reliable radio communications even in critical conditions, communications which, in turn, being reliable, allow exploiting considerable computational power that can be allocated to the control station 110, simply by equipping the drones with minimal computational means, sufficient to control their operational functionality, their equipment and the transmission of acquired data to the control station.

[0124] More complex processing, synthesizing the collected data, does not need to be carried out on board the drone, given that the instructions to carry out the various missions can be reliably transmitted to the mission 130 drone, even when it is in the flames of a fire. Petition 870250085417, dated 09 / 22 / 2025, pp. 104 / 145 26 / 29 Final Observations

[0125] Finally, the system for determining the flight paths of a heat-resistant drone, according to the present invention, compared to traditional solutions proposed by the state of the art, offers insights that bring improvements in the early management of forest fires. In fact, it is assumed that the invention defines a category of monitoring system capable of characterizing and addressing the principles of fires that arise in open environments; this category of systems is characterized by the availability of drones 130 that can be made heat-resistant and equipped to perform very reckless missions, at the limit of their resistance capacity, in extreme environmental contexts, such as those generated during fires.

[0126] The teachings of the invention can be applied to a wide variety of approaches to the problem of containing forest fires, but all of these approaches, if they implement these teachings, can achieve better performance and results than those that can be achieved today using only the known technique.

[0127] The peculiarity of the invention lies in the planning of controlled flight paths involving pairs of drones, which divide their tasks efficiently, and which allow the prediction models to work with reliable data.

[0128] Since the applicability of the invention is very varied, the invention itself lends itself to numerous variations, being able to exploit different types of drones, as well as drones with different tasks. However, it is essential to be able to use drones, that is, one of the most important assets of the fire management system, in the most flexible way possible, in order to be able to optimize their use in all possible situations. Thus, the invention, in its preferred embodiments, provides for the use of a fleet of drones substantially of the same type, but configurable to perform different functions, equipping them from time to time with different “payloads”.

[0129] Other variants may also relate to the ideal flight path that the planning system provides to mission drones 130, which may respond to Petition 870250085417, dated 09 / 22 / 2025, pages 105 / 145 27 / 29 several optimization criteria, what matters is that the system that calculates this ideal trajectory can have information that allows the 130 heat-resistant mission drones to approach the limit of their capabilities, with sufficient assurance that the assigned task can be successfully completed.

[0130] The use of the plural, when referring to mission drones 130, also indicates another possible application variant, which consists of planning intervention missions involving a plurality of heat-resistant mission drones 130 (also with different “payloads” and different tasks) that cooperate in a single mission, and which can be configured to act according to the situation they encounter: therefore, their tasks can undergo modifications and adaptations during the mission itself. And all mission drones operating in the same location can benefit from the data collected by a single observation drone. In this case, each single mission drone 130 is still coupled with an observation drone 120, even though the latter, in turn, can also be coupled with another mission drone operating in the same area.

[0131] Other variations may also relate to the functions for which the various drones can be prepared. As an example, an additional function, but obviously there could be many others, could be to emit an acoustic signal for the benefit of all people involved in an area affected by the fire, in order to provide them with help to save themselves.

[0132] Furthermore, the invention itself can be implemented in an essential manner, as described in this description with the aid of Figure 1, or it can be enhanced with other useful features.

[0133] For example, both the observation drone 120 and the heat-resistant mission drone 130 may have a much richer sensory apparatus than that mentioned, in which, in addition to the temperature sensor, other sensors are present. Among the sensors that certainly seem very interesting for the application considered, especially in the heat-resistant drone 130, we mention sensors suitable for detecting pressure, or data on air composition, or on the Petition 870250085417, dated 09 / 22 / 2025, pp. 106 / 145 28 / 29 presence of turbulence and any air currents, especially those that are usually created in the vicinity of a fire.

[0134] Some of this data, in addition to trajectory planning, can also be useful for real-time planning of tasks to be assigned to heat-resistant mission drones 130, while they are already on mission.

[0135] The availability of a fleet with many drones is also justified because often (especially in arson fires) several locations are affected simultaneously by a fire.

[0136] In these cases, if it is not possible to intervene in all fire outbreaks simultaneously, it is necessary to make a decision on priority locations that can be defined using a predictive calculation model that promptly identifies the location where the effect of the fire is most dangerous. If, for example, five locations distant from each other are attacked by fire at the same time, they will have different fire outbreak developments, and the model, through fire evolution simulation, will choose the location where the fire will develop fastest, for example taking into account the wind speed at the various locations.

[0137] Even telecommunications equipment can be suitable for establishing a plurality of connections with different entities, ranging from fixed stations installed in the woods, through the central observation station, to the installation of direct connections with other means involved in fire management, such as other drones or emergency vehicles of various types, or with operational posts of personnel who are working, including in the field, on containing the fire.

[0138] Furthermore, especially if in the future the approach of developing an infrastructure for forest fire management becomes a widespread approach, it is foreseeable that new technologies will become available to create increasingly specialized sensors for this application and, therefore, both drones and the eventual network of sensors disseminated in the monitored forest could enrich the information to be processed to feed both the environmental model and the Petition 870250085417, dated 09 / 22 / 2025, pp. 107 / 145 29 / 29 program for calculating the ideal trajectory, thus providing new improvements associated with the present invention.

[0139] Therefore, especially in the context of expected evolutionary scenarios, the invention lends itself to incorporating and supporting further development and improvement efforts capable of improving the performance of the described system. It is concluded that many further developments could be made by one skilled in the art without thereby departing from the scope of the invention as it results from the present description and the appended claims that form an integral part thereof; or, if such developments are not included in the present description, they may be the subject of other patent applications associated with, or dependent on, the present invention. Petition 870250085417, dated 09 / 22 / 2025, pp. 108 / 145

Claims

1 / 3 CLAIMS System for determining safe flight paths for a mission drone (130), characterized in that it is associated with an information sheet specifying: ^ the maximum endurance time of the drone itself at various temperatures, i.e., how long the said drone can function correctly when operating at high temperatures; ^ the minimum and maximum flight speeds according to the payload with which it is equipped; ^ the flight range, i.e., the energy or fuel consumption according to the payload with which it is equipped; - whereby said mission drone (130) includes: ^ means of two-way radio communication between said mission drone (130) and at least one second radio station; ^ at least one temperature sensor; ^ means of memory suitable for memorizing at least one flight path;^ suitable geolocation means to detect the instantaneous position and speed of the mission drone itself (130), to verify, while in flight, and even if approximately, whether the flight path it is taking is compatible, or not, with said at least one memorized flight path; said system for determining safe flight paths for a mission drone (130) further comprises: A. a second observation drone (120) equipped with temperature sensors, a thermal camera and sensors for acquiring wind speed and direction; B. computational means also designed to determine said safe flight paths for the mission drone;C. an environmental model that represents, in computational format, the physical environment containing the flight paths determined for the aforementioned mission drone, Petition 870250085417, dated 09 / 22 / 2025, p. 109 / 145 2 / 3, in which the aforementioned environmental model presents: a. the temperature values ​​of all points of the aforementioned represented physical environment are substantially updated in real time; b. it is appropriate to simulate the evolution of temperatures in the near future, in case of a fire that develops in said physical environment; c. said simulations are executed by means of a simulation program, executed by means of said computing means, and configured to process some input data, including at least: i. temperature data, also detected by said thermal imaging camera with which said second observation drone (120) is equipped, and which is positioned at a safe height in relation to a possible fire;ii. data regarding wind speed and direction, detected by special sensors (121) with which the said second observation drone (120) is equipped; iii. data describing the vegetation present in said environment represented by said environmental model, where said descriptive data of the vegetation comprise a parameter that expresses the combustibility of the vegetation described.; 2. System for determining safe flight paths for a mission drone (130), according to claim 1, characterized in that said mission drone (130) is a heat-resistant drone, being fitted with a heat-resistant coating, or painted with heat-resistant protective paints.

3. System for determining safe flight paths for a mission drone (130), according to claim 1, characterized in that said at least one memorized flight path is calculated and updated substantially in real time, as a function of temperature evolution, according to values ​​calculated by means of simulations performed with said environmental models.

4. System for determining safe flight paths for a mission drone (130), according to claim 1, characterized in that it comprises at least one monitoring station (110) located in a fixed elevated position, Petition 870250085417, dated 22 / 09 / 2025, page 110 / 145 3 / 3 wherein said observation drone (120) is equipped to maintain a direct radio connection (321) with said at least one monitoring station (110).

5. System for determining safe flight paths for a mission drone (130), according to claim 1, characterized in that said second at least one radio station with which said heat-resistant drone (130) is enabled to communicate is located on said observation drone (120).

6. System for determining safe flight paths for a mission drone (130), according to claim 1, characterized in that said mission drone (130) is also equipped with dispensers of substances with extinguishing properties.

7. System for determining safe flight paths for a mission drone (130), according to claim 1, characterized in that said mission drone (130) is also equipped with a video camera.

8. System for determining safe flight paths for a mission drone (130), according to claim 1, characterized in that said mission drone (130) is also equipped with one or more environmental sensors to measure any air currents.

9. System for determining safe flight paths for a mission drone (130), according to claim 1, characterized in that said mission drone (130) is also equipped with one or more environmental sensors to detect information about the composition of the air.

10. System for determining safe flight paths for a mission drone (130), according to claim 1, characterized in that said environmental model is suitable for simulating the evolution of temperatures in the near future in case of fire, and is made with “WRF-Fire” technology. Petition 870250085417, dated 22 / 09 / 2025, p. 111 / 145

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