This paper explores the directions for the application of unmanned aerial vehicles in the provision of security to vital elements of a country’s critical infrastructure. The analysis focuses on two paths of development: the first one refers to the transportation system, the latter is related to the gas supply network – the basic components of a country’s critical infrastructure. The first section of this paper will examine the current state of knowledge in the field, and is designed as a reference of terminology pertaining to unmanned aerial vehicles (definitions and classification). The section shall furthermore provide a basis for and a contribution to the developed conceptual-semantic framework for UAV research. The first direction of development is described in terms of the characteristics and assumptions of the system; this includes an overview of the specific requirements of the unmanned platform itself, as well as the elements of the system, such as a local monitoring centre and other components. Furthermore, this section provides the overview of the designated mobile application, whose development is expected to improve the efficiency of system operation, which is a conceptual novelty considering similar developments. The second direction concerns the development of an unmanned system of production, storage, and use of chemical and radioactive substances, including pipelines for hazardous substances. The programme that fits perfectly in the framework of the second considered branch of development is “Cricket” [Polish: “Świerszcz”] – a programme implemented in the periodic inspection of gas supply infrastructure. The description of the programme in question included specifying the technical and operational requirements for the fight devices as well as for the equipment.
The key features of unmanned aerial vehicles, such as relatively low production cost, low technical support costs, long flight time with no need for intermediate landing and high maximum altitude, contribute to their growing popularity as a solution for monitoring and detecting diverse types of threats. Among the recently developed applications of this type of aerial vehicles are applications that monitor traffic incidents and gas conduit networks.
Attempting to select and define the directions of development, it is essential to underline the fact that both the transportation system and the gas supply constitute elements of every country’s critical infrastructure (CI), which can be defined as a system of interconnected functional objects, such as buildings, facilities, installations and services of key importance to the security of the state and its citizens; furthermore, the infrastructure is to ensure the efficient functioning of public administration authorities, institutions and enterprises. Critical infrastructure includes: energy, energy resources and fuel supply, communication systems, teleinformation networks, financial systems, food supply systems, water supply systems, health protection systems, transportation systems, rescue systems, as well as systems ensuring the continuity of public administration activities, systems of production, storing and use of chemical and radioactive substances, including pipelines for hazardous substances. The provision of protection to critical infrastructure may be understood as any measures aiming to ensure the functionality, continuity of operation and integrity of critical infrastructure to prevent threats, risks or weaknesses, as well as limiting and neutralising the effects of system failure or breakdown and its immediate reconstruction in the event of a breakdown, attacks and other events disturbing its proper functioning (National Critical Infrastructure Protection Programme 2015, pp. 4-6).
The analysis that follows deals with, on the one hand, the transportation and communication systems, and secondly, with the gas supply conduit system, focusing on production, storage and use of chemicals and radioactive substances (Emergency Management Act 2007). It is crucial to highlight the fact that these systems determine the existence and proper functioning of a state, while all the negative outcomes may result in the disruption of its proper functioning; hence, the protection of a country’s critical infrastructure constitutes a priority task. In their essence, the tasks related to critical infrastructure go beyond ensuring a proper level of protection against diverse threats, and should embrace handling potential damage or disruption of its functioning at a possibly shortest time, ensuring that if these do happen, they are relatively easy to remove and do not cause additional losses for citizens and the economy.
When taking up the subject of unmanned aerial vehicles, it is vital to overview the subject literature so as to present and systematise terminology related to this particular type of aerial vehicle.
In contemporary terminology, any aircraft capable of multiple flights without any crew or passengers on board is referred to as an unmanned aerial vehicle. This type of aerial vehicle is considered as an element of an unmanned aerial system (UAS). It is a complete system, which comprises the unmanned aerial vehicle itself, a ground control system, and any auxiliary equipment included therein. An unmanned aerial vehicle can therefore be understood as a central element of an unmanned aerial system.
Another definition of an unmanned aerial vehicle can be found in the NATO terminology. It is understood as:
In the field of unmanned aerial vehicles, we can also see a tendency for building constructions which can be used both as manned and unmanned platforms. They are referred to as
In contemporary colloquial language, unmanned aerial vehicles are often referred to as drones. However, this term is not recommended and should be replaced by a proper technical nomenclature (
Unmanned aerial vehicles come in a variety of designs, which determine their basic flight parameters, such as: range, altitude, and endurance. Taking into account the above specifications, UAVs have been divided into classes and categories, as shown in the tables below (
Classifi cation of Unmanned Aerial Vehicles acc. to the General Staff of the Polish Armed Forces (
Class | Category | Altitude [m] | Range [km] |
---|---|---|---|
Small | ↓366 | 50 | |
Mini | ↓305 | 25 | |
Micro | ↓60 | 5 | |
Tactical | ↓915 | 200 | |
HALE | ↓19 812 | infinite | |
MALE | ↓12 192 | infinite |
High Altitude Long Endurance
Medium Altitude Long Endurance
Classifi cation of Unmanned Aerial Vehicles acc. to scholars from the Military University of Technology (
Category | Designation | Altitude [m] | Range [km] | Flight endurance [h] |
---|---|---|---|---|
Micro | Micro | 250 | ↓10 | 1 |
Mini | Mini | 350 | ↓10 | ↓2 |
Close range | Close Range (CR) | 3000 | 10÷30 | 3÷6 |
Short range | Short Range (SR) | 3000 | 30÷70 | 3÷6 |
Medium range | Medium Range (MR) | 3000÷5000 | 70÷200 | 6÷10 |
Medium range, high flight endurance | MR Endurance (MRE) | 5000÷8000 | ↑ 500 | 10÷18 |
Low altitude, deep penetration | Low Altitude Deep Penetration (LADP) | 50÷9000 | ↑ 250 | 0,5÷10 |
Low altitude, high flight endurance | Low Altitude Endurance(LAE) | 3000 | ↑ 500 | ↑ 24 |
Medium altitude, high flight endurance | Medium Altitude Long Endurance (MALE) | 5000÷8000 | ↑ 500 | 24÷48 |
High altitude, high flight endurance | High Altitude Long Endurance | 15 000÷20 000 | ↑ 1000 | 24÷48 |
Unmanned combat Aerial Vehicles | Unmanned Combat Aerial Vehicle (UCAV) | ↑ 20 000 | 400 | 2 |
The versatile capabilities of UAVs may find application in road accident rescue. Unmanned platforms soaring in the skies provide a considerably better perspective than the view from the roadside. This type of aerial vehicle requires no assistance in recording an incident, and is capable of processing data obtained from various sources and passing a detailed report on the current state of events and developments to headquarters. These activities aid the decision-making process by providing specific information regarding the rescue needs, thus enabling the necessary numbers of rescue forces to be summoned (
The rescue needs described in the preceding paragraph could provide the foundation for the development of an unmanned aircraft road accident rescue system. The system should include a local traffic and transport CCTV centre and operations centre, and above all specialist UAVs, whose objectives will be to:
− monitor and identify road incidents,
− supply medications and equipment to the site of the accident,
− transport victims to hospital.
In any case, the communication between the dispatcher located in the operations centre and the individuals on site at an accident is an absolute necessity to ensure the system functions properly, regardless of the condition of the victims. The classification of motor vehicle traffic crashes differentiates between a road collision and a road accident according to the health condition of the participants (
Regarding the equipment of unmanned aircraft used by the services (
Thermal imaging used in UAVs employs radiation below the visible light wavelength range and exploits the difference in ambient temperature and temperature emitted by a living organism to produce the image. With no additional lighting involved, this method enables the operator to spot people in bushes, vehicles, hidden under trees or buried in the ground. In thermal imaging cameras, the object is generated from the heat it emits. Therefore, the radiation range exhibits absolute independence of the environmental factors. To embrace the full capabilities of thermal imaging cameras, they could be used in systems coupled with visible- spectrum cameras (
While conducting a rescue operation, it is crucial to simultaneously observe the image from both the thermal and traditional camera. Parallel transmission facilitates the search process and increases the effectiveness of performed activities. The UAV-led activities do not have to be limited to mere observation of images, they can also involve the use of specialist software. These light and simultaneously very easily implemented platforms can instantly deliver high quality photos from both the air and ground (
Specialist software plays an important role in the use of UAVs in road accident rescue. The
The flight routes can be adapted to any terrain: hills, mountains, trees or flat land. The software allows users to choose an automatic search mode, which operates on such variables as: altitude, field of view, the UAV battery life and probability of detection. Practical experience has shown that for a five-strong emergency team, an application requires an average of two hours to successfully find a victim in an area of one square kilometre. Computer analysis of images during search missions is typically aided by artificial intelligence methods.
In the
The search operation scheme based on Search Mission Manager software (
Statistics show that the most common cause of death among victims of accidents and road incidents is cardiac arrest: in certain cases, using a defibrillator could save lives. Already in 2013, researchers had attempted to develop an unmanned vehicle that would be able to transport a defibrillator. The result of their work, the
Another application of the UAV in the event of traffic incidents is the transport of victims to hospital. The first unmanned system of this type was created for military needs. The
One of the methods for addressing critical infrastructure security challenges with the help of the UAV has taken the form of
The project fits in the framework of the
The solution will include such elements as: an unmanned vehicle capable of performing ordered tasks, logistics support enabling effi cient and uninterrupted execution of tasks in field conditions (constituting a subsystem of a logistics support system that will consist of a control and navigation system and a transport and technical support subsystem). The platform will need to include indispensable structural components,
The developments in the field of additive manufacturing have allowed a reduction in the weight of joints and fasteners compared to traditional methods (milling) by approx. 75%. Additive-manufactured fasteners exhibit sufficient durability, and what is more, this manufacturing method virtually eliminates post-production waste generation, hence reducing production costs.
Moreover, the energy consumption generated by the inspection of the supply network will be reduced, since at present, full-scale, manned helicopters are in service. Unmanned platforms, due to their significantly lower mass (the mass of the final product is expected not to exceed 150 kg - which is less than the total mass of the pilot and operator alone, not including the mass of the conventional manned helicopter itself), are notable for their several-fold lower energy use when covering the same distance, at the same time. In addition, since the method enables approaching the immediate environment of the gas pipeline, the annual inspection time interval will be extended as well. What is more, the application of methane detection sensors will undoubtedly increase the reliability of inspection, which at present relies solely on the organoleptic testing and experience of the helicopter crew.
The innovation of this new type of unmanned aircraft product predominantly consists in that it integrates the features of a rotorcraft and a fixed-wing aircraft. The desired features of the multi-rotor vehicle include: vertical take-off, hovering during flight and safe landing in virtually any conditions. However, with regard to drawbacks, this UAV shows high demand for energy, which furthermore can only be stored in batteries, which in turn means the vehicle has a limited range. Fixed- wing aircraft are free from such limitations: they combine an extensive range with considerably higher cruising speeds. An aircraft that would integrate these features would become a perfect solution for monitoring gas supply networks. Currently, the inspection is conducted by highly specialised pilots who, working in teams with an observer, perform flight missions over gas supply networks in a conventional aircraft. Furthermore, gas leakage is most commonly diagnosed organoleptically,
Another method for the diagnosis of leakage of an underground gas pipeline is the observation of local collapses in the terrain, which typically evidence the leaching of the soil by the released gas. Similarly to the vegetation observation method, serious limitations are encountered in winter – when the frozen ground blocks the gas from leaking into the atmosphere, causing it to find its outlet further away from leakage site. The developed UAV is to be equipped with methane detection instrumentation, which combined with the small size and high-precision autonomous control system, will enable the gas pipeline to be approached at a sufficient distance to take measurements. Therefore, maintenance of gas conduits will be possible regardless of the weather – throughout the year, and, moreover, the entire operation will be considerably more economical. The proposed UAV has a novel design, which combines the features of a quadrocopter and a fixed-wing aircraft, merging the advantages of both solutions. Thanks to four rotors with a vertical axis of rotation, the vehicle takes off and lands in practically any place, and most importantly from the viewpoint of damage detection – the UAV is capable of hovering. On the other hand, by implementing a propeller with a horizontal axis of rotation, its flight parameters will match that of the fixed- wing aircraft. Such UAVs are capable of covering much longer distances and developing higher cruising speeds compared to conventional multi-rotor aircraft vehicles. The platform will be equipped with technical instrumentation for leak detection and the optical recording system for the immediate vicinity of the gas supply network, control and navigation system and remote sensing; whereas the designated IT system will allow the processing of acquired data. In addition, UAVs equipped with cameras will be able to perform important functions in monitoring areas, detecting land collapses (leak detection) and taking aerial photographs, which will provide the basis for the creation of orthophotomaps
Apart from the flying base, the platform includes the technical instrumentation for leakage detection and optical recording of the supply network vicinity, and the designated IT system will enable processing of the acquired data.
System operation will be relatively simple and will not require specialist knowledge from the operator. The UAV is transported to the place of measurement in a car equipped with IT equipment for data acquisition and analysis. Once airborne, the UAV, controlled by the programmed autopilot and the operator, will execute the route to the destined place of landing, which was optimised so as to maximally extend the flight without the need to refill the battery/fuel. Changing the power supply or refuelling will be carried out with ease in field conditions, following which the UAV will be ready to continue to conduct new measurements on the subsequent section of the supply network. If, during the flight, a methane leak or a change in vegetation colour is diagnosed as deviating from the norm, the UAV will initiate the hover move and the operator will take over the control. If no gas leak is detected, the UAV, depending on the remaining energy, will proceed to inspect the next section, or return to the operator to refuel/replace the batteries. The UAV operator will additionally be equipped with a manual laser
According to the plan, the three built tester mock-ups will be scaled down to approx. 1:2 of the original design, however, their exact scale will depend on the optimisation of the tester weight at the constraint of maintaining the flight time. The primary reason for building the mock-ups is for the purpose of testing the correct operation of the entire system. The
In addition, the UAV equipped with traditional photo-cameras operating in the visible light range and MOSP (
The diagnostic flight will execute the pre-defined flight route based on the geographical coordinates of the pipeline. Regardless of the initially defined route of the carrier unit, the multiple-scope sensor module will also enable pre-defining the pipeline location. These systems, assisted by the inertial stabilisation function of the module frame, will ensure the control/directing of the optical axis of the module’s optic-measurement devices directly on the defined pipeline route, regardless of any disturbances acting on the carrier unit (
The project’s success from the IT/measurement system perspective will be marked by the moment when the objective proof of capabilities is delivered,
The presented scientific considerations on the application of unmanned aerial vehicles focused on two directions of developments – both concerning the protection of the critical infrastructure elements, as the fundamental factor in the provision of high-level internal security. In the course of this analysis, it was resolved that it would be appropriate to collect and organise the current state of knowledge on unmanned aerial vehicles by presenting the relevant definitions and classifications, and thus creating a conceptual and semantic grid for future reference.
With regard to the first anticipated direction of development and application of UAVs – as a road accident rescue solution, it ought to be remarked that due to their extensive capabilities (the ability to monitor from the air, long flight time), these systems appear to be an extremely promising alternative. They can record traffic incidents, and may prove decisive in providing help to victims, which is extremely important in the event of a threat to human life. Harnessing the capabilities of UAV-based systems would require establishing a local monitoring centre equipped with a real-time data transmission system. Considering the aerial vehicles themselves, it was resolved that they should be equipped with optical sensors operating in the visible light and infrared wavelength range, as well as in night vision systems. The designed UAV system could be extended by a dedicated mobile application, which would support the system operation by aiding the location of injured individuals and optimising the search area.
Analysing the second of the UAV development paths, the provision of security to the state’s critical infrastructure through protection of gas supply networks pointed to the native development concept - a programme under the codename “
Digital images are obtained in two ways:
by digitising analogue images (typically involving a scanning aperture in a range of 15 to 30 μm, and special photogrammetric scanners, with geometric accuracy in the order of ± 1-2 μm. by using special scanners and digital cameras, in which the image of the object is recorded not on the photographic material, but by means of a special sensor – in digital form (such a sensor may be a linear system or a matrix of CCD elements (
The data providing the basis for the generation of orthophotomaps are: aerial photographs, elements of internal and external orientation of images, and the Digital Terrain Model (DTM). DTM is a discreet (expressed by points) numerical representation of the topographic elevation of the terrain surface with an interpolation algorithm, which enables the reproduction of its topography over a specific area. DTM is represented by points spread regularly or irregularly on the terrain surface and extended by points describing the morphological forms of the represented terrain (Digital Ortophotomap and Digital Terrain Model).