The unmanned systems industry suggests a wide range of possibilities in the modern world. Indeed, recent technological advancements in automation allow accomplishing tasks “in a quick, safe, and cost-efficient manner” (Albeaino et al., 2019, p. 381). As a result, different operational spheres, such as air, ground, and marine, actively employ these systems. In each particular domain, unmanned systems demonstrate specific features in terms of design, as well as command, control, and communication (C3) technologies. Therefore, it is relevant to analyze the functional performance and architecture of unmanned systems in these subject areas.
In the aircraft domain, unmanned systems involve a range of specific technological components. For instance, Albeaino et al. (2019) focused on such elements as “flying styles, types of platforms, and onboard sensors” in pilotless airborne systems (p. 381). In particular, the researchers identified three major types of flying styles: autonomous navigation, manual control, and semi-autonomous mode, which implies a combination of computer autonomy and human intervention (Albeaino et al., 2019). The autonomous navigation has an undeniable advantage since it does not require a high level of operator’s expertise as compared to the manual mode. However, the manual flying style enables better adaptability of the device in terms of severe weather conditions. At the same time, the semi-autonomous navigation may be more useful to “handle environmental complexity (namely confined spaces)” (Albeaino et al., 2019, p. 393). As one can observe, the choice of a flying style for unmanned aerial vehicles largely depends on a specific context of their application.
There are also three types of platforms in unmanned aerial devices. These types include rotary-wing platforms, fixed-wing constructions, and blimps, with each of them demonstrating certain peculiarities in terms of command and control (Albeaino et al., 2019). For instance, rotary-wing vehicles embrace “helicopters, quadcopters, hexacopters, and octocopters” (Albeaino et al., 2019, p. 394). Advantages of this type of platform include their abilities “to take-off and land, on rough surfaces, and without the need of large runways” as compared to fixed-wing vehicles (Albeaino et al., 2019, p. 394). On the other hand, fixed-wing vehicles are capable of flying longer distances and demonstrate a higher payload capability. At the same time, blimps, also defined as aerostats, are lighter-than-air crafts, allowing a longer flying time as compared to other types of platforms (Albeaino et al., 2019). Hence, the purpose of the application determines the type of platform for unmanned systems in the aircraft domain.
As to the communication technologies in the aircraft sphere, unmanned systems rely on the design of their mounted onboard sensors. Typical informational contents of built-in sensors usually include “global positioning, altimeter, inertial measurement unit, barometers, humidity, temperature, and obstacle avoidance” (Albeaino et al., 2019, p. 395). Modern unmanned systems are also often equipped with more advanced communication technologies, such as cameras, thermal imagery devices, laser radars, scanners, ultrasonic beacons, and radio frequency identification devices (Albeaino et al., 2019). All these communication technologies ensure the adequate performance of unmanned aerial vehicles.
The unmanned spacecraft system architecture also possesses its unique features. Indeed, these systems require a high level of design automation, which is currently the focus of researchers’ attention (Akhtulov, 2019). For instance, the spacecraft technology relies on “the method of transfer functions,” which “allows to determine the level of loads acting on the structure” (Akhtulov, 2019, p. 7). In this regard, the “integrated” systems of command, control, and communication are applied (Akhtulov, 2019, p. 1). This system allows the researchers to automate the entire chain of design operations with consideration of the possibilities of the computer and the designer. It suggests a set of multiple algorithms, which provide solutions on speed for different tasks. Besides, it ensures a “continuous control of the work,” as well as the user-friendly internal and external exchange of information. Thus, spacecraft systems demonstrate a range of specific features in terms of C3 technologies.
Similarly to aircraft systems, unmanned ground vehicles can also operate in two modes: “the remote-controlled mode, and the autonomous mode” (Man et al., 2018, p. 319). The first mode implies the user’s complete control over the vehicle’s operations and movements. This type of navigation resembles operating “a remote-controlled car with live video streaming on a mobile application” (Man et al., 2018, p. 319). On the other hand, the autonomous mode relies on the mobile application to select the destination. However, unmanned ground vehicles reveal several peculiarities, such as reading directions from QR codes and calculating the minimum-time route to its final destination. Furthermore, the system uses infrared scanners, ultrasonic sensors, and webcam, which provide it with necessary information about the direction and possible obstacles on its way.
Maritime unmanned systems are also quite widespread. In particular, underwater vehicles are useful in wartime since they can operate without being detected by the enemy (Heo et al., 2017). Furthermore, the unmanned control allows for a significantly smaller size of vehicles and thus lower costs for construction. Besides, these systems can handle “the hostile and dangerous missions without fear of losing human lives” (Heo et al., 2017, p. 29). Moreover, unmanned vehicles can spare human operators from carrying out monotonous tasks. There are several significant tendencies within the framework of unmanned systems design. These types include screw-driven unmanned underwater systems, underwater gliders, and bionic underwater vehicles.
The screw driven type was the first device, classified as an underwater vehicle. Since the time of its invention in 1957, this unmanned system, operated by screw propellers, has been significantly improved (Gafurov & Klochkov, 2015). For instance, it has been equipped with solar panels, allowing the device to carry out its missions for more extended periods. Moreover, the system has “a large number of sensors and measuring devices,” and control of this type of underwater vehicle occurs through acoustic communication (Gafurov & Klochkov, 2015, p. 142). Another essential design feature of screw-driven underwater vehicles is their inherent modularity, that is, the ability to change equipment components depending on the purpose. This peculiarity ensures the system’s universality in terms of performing different tasks.
The design of underwater gliders allows them to operate for several weeks or even months. Unlike screw-based vehicles, these systems are buoyancy-driven and autonomous (Gafurov & Klochkov, 2015). For communication and navigation, the system employs antenna, located at its tail. The glider’s command relies on hydrophone technology. The battery-powered hydraulic system ensures the control of the vehicle’s buoyancy. It is necessary to observe that the silent operation mode of underwater gliders made them a perfect option for military purposes.
It is necessary to observe that the architecture of unmanned underwater systems primarily focuses on the size reduction of their components, as well as the entire vehicle. As a result, one can distinguish “mini-automated underwater vehicles (mass from 20 till 100 kilograms) and micro-automated underwater vehicles (mass up to 20 kilograms)” (Gafurov & Klochkov, 2015, p. 144). In particular, the bionic micro-automated underwater vehicles represent one of the most actively developing subtypes of unmanned systems in the maritime domain. These vehicles have numerous advantages in terms of their control. One of such benefits is their inherent maneuverability (Gafurov & Klochkov, 2015). Indeed, bionic systems have not only swimming but also crawling capabilities, thus enabling them to operate in a shallow environment. The design based on “fins and tail, driven by an electric motor” is another distinctive feature of this type of vehicle (Gafurov & Klochkov, 2015, p. 144). These architecture features ensure a high level of mobility and expand the device’s possibilities of self-navigation.
Thus, the unmanned systems in the operational domains of air, ground, and marine demonstrate a range of similarities and dissimilarities in terms of command, control, and communication technologies. In all these subject areas, unmanned vehicles aim to reach an optimal mode of operation and high-performance levels, taking into account the context of the performed task. To this end, one can distinguish several options for operation modes in all domains under consideration. These options include autonomous, semi-autonomous, or manual control modes, depending on a particular setting. In other words, control technologies are quite similar for aircraft, ground, and maritime areas.
However, there are distinct dissimilarities in terms of command and communication. Indeed, each domain applies its features to streamline the command process in operating unmanned systems. For instance, spacecraft vehicles use the “integrated” system of command, control, and communication. Meanwhile, aircraft systems rely on mounted onboard sensors with advanced communication technologies, whereas ground unmanned vehicles employ QR codes reading, whereas. Moreover, unmanned systems in the discussed domains naturally possess distinct features in terms of design, depending on the environment in which they operate. However, the dissimilarities mentioned above are united by virtually the same purpose. All these peculiarities in terms of design and C3 technologies target at finding an optimal performance solution. Thus, the specific features of unmanned systems aim to provide the best and most efficient service possible.
References
Akhtulov, A. (2019). Methodology and practical application of the automation system for unmanned spacecraft design. Journal of Physics: Conference Series, 1399(4), 1–7.
Albeaino G., Gheisari, M., & Franz, B. (2019). A systematic review of unmanned aerial vehicle application areas and technologies in the AEC domain. Electronic Journal of Information Technology in Construction, 24, 381–405.
Gafurov, S., & Klochkov, E. (2015). Autonomous unmanned underwater vehicles development tendencies. Procedia Engineering, 106, 141–148.
Heo, J., Kim, J., & Kwon, Y. (2017). Technology development of unmanned underwater vehicles (UUVs). Journal of Computer and Communications, 5(7), 28–35.
Man, C., Koonjul, Y., & Nagowah, L. (2018). A low cost autonomous unmanned ground vehicle. Future Computing and Informatics Journal, 3(2), 304–320.