, ‛Design and Integration of Flexi Bird - a low cost sub-scale research aircraft for safety and environmental issues’, 27th International Congress of the Aeronautical Sciences, Nice, [September 2010]. Grenzdörffer, GJ, Engelb, A & Teichert, B 2008, ‛The photogrammetric potential of low-cost UAV’s in forestry and agriculture’, The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol, XXXVII, part B1. Koski, WR, Abgrall, P & Yazvenko, SB 2010, ‛An inventory and evaluation of unmanned aerial systems for offshore surveys of marine
References . M. Rodzewicz, D. Glowacki Investigations into load spectrum and strength tests of an UAV structure, The READ 2012 Conference (Research and Education in Aircraft Design) – October 2012 Brno . M. Rodzewicz Determination and extrapolation of the glider load spectra. Volume 80 Issue 5 of Aircraft Engineering and Aerospace Technology, pp. 487 – 496 . M. Rodzewicz Fatigue evaluation of high-loaded aeronautical composite structures. Aircraft Engineering and Aerospace Technology, Vol 81, No 5, pp 452 – 460 . Rodzewicz M., Czerwiňski G
REFERENCES 1. Ambroziak L., Gosiewski Z. (2014), Two stage switching control for autonomous formation flight of Unmanned Aerial Vehicles, Aerospace Science and Technology , 46, 221-226. 2. Askari A., Mortazavi M., Talebi H.A. (2015), UAV Formation Control via Virtual Structure Approach, Journal of Aerospace Engineering , 28(1). 3. Cai D., Sun J., Wu S. (2012), UAVs Formation Flight Control Based on Behavior and Virtual Structure, AsiaSim 2012, Communications in Computer and Information Science , 325, 429-438. 4. Kownacki C., Ołdziej D. (2015), Flocking
REFERENCES Aslanyan, A. E. (1984). Aircraft Automatic Flight Control Systems . Vol. I, Kiev Air Force Institute. Kiev, Ukraine: University Press. Beseda-Portas, E., de la Torre, L., de la Cruz, J. M., & Bonifacio, A.-T. (2010). Evolutionary Trajectory Planner for Multiply UAVs in Realistic Scenarios. IEEE Transactions on Robotics, Vol. 26, No. 4 , 619-634. Castelli, T., Sharghi, A., Harper, D., Tremeau, A., & Shah, M. (2015). Autonomous navigation for low-altitude UAVs in urban areas. Engineering, Computer Science, Cornell University . Eng, Pilar., C. S
6. References 1. Biała Księga Rynku Bezzałogowych Statków Powietrznych, Ministerstwo Infrastruktury, Warszawa, luty 2019. 2. Grymek S.: Modele strumienia powietrza w pneumatyce. Politechnika Gdańska, Gdańsk 2012. 3. Jastrzębski G.: Description of the pneumatic work cycle of the starting unit of the UAV launcher. Journal of KONES, tom 4, nr 24, 2017. 4. Jastrzębski G.: Impact of opening time of the take-off pneumatic luncher main valve on take-off pressure losses. Journal of KONES, tom 23, nr 4, 2016. 5. Nawrat A.: Modelowanie i sterowanie bezzałogowych obiektów
BIBLIOGRAPHY  Reg, A., 2010, Unnamed aircraft system of UAVS design, development and deployment , A John Wiley and Sons, Ltd.  Dudek, B., 2011, „Live working in industrial network” (“Prace pod napięciem w sieci przesyłowej”), Handbook INPE No. 36, (in Polish).  Dudek B. and Czapaj R., 2007, „Advances in robotics and IS techniques in network works, especially under voltage” („Postęp w dziedzinie robotyzacji i technik SI w pracach sieciowych zwłaszcza pod napięciem”), IX Conference „Live working in nn, SN and WN networks in Poland and in the world), pp
-770X), 1/2008, pp(1-14).  Szabolcsi Róbert, Egy felmérés margójára - néhány gondolat a pilóta nélküli repülőgépek polgári és katonai alkalmazásáról. Szolnoki Tudományos Közlemények (ISSN: 1419-256X) (eISSN: 2060-3002), 1/2008, pp(1-12).  Róbert Szabolcsi, Conceptual Design of the Unmanned Aerial Vehicle Systems Used for Military Applications. Scientific Bulletin of “Henri Coanda” Air Force Academy, ISSN: 2067-0850, 1/2009, pp(61-68).  Szabolcsi Róbert, Forgószárnyú és/vagy merevszárnyú UAV alkalmazások. Műszaki Tudomány az Észak-Alföldi régióban 2010
, Vol. II-5/W1, 283-288. Tomaszewski, A. (2007). Rola dziedzictwa kulturowego dla współczesnej cywilizacji. Przestrzeń dziedzictwa, Roczniki Geomatyki , 5 (8), 21–25. Wojciechowska, G., & Łuczak, J. (2018). Use of close-range photogrammetry and UAV in documentation of architecture monuments, E3S Web Conf.,71, 00017.
Nowadays, civil UAV industry market grows rapidly. This expansion is followed by the new requirements and expectations against UAVs, which force their constructors to look for less typical solutions.
Expected long time endurance and range are the typical examples of such expectations. Clients are often looking for UAV with VTOL ability and time of flight much greater than 30 minutes and long range. They want to inspect large areas, i.e. between major cities without need of paying for building and maintaining developed aircraft infrastructure. Example of UAV with low infrastructure requirements are multirotors. Major disadvantage of them is short flight time. Elongating time of flight is hard to achieve by classical multirotor with standard Li-Pol batteries available on the market. They have too low energy density in currently used technology. Alternative power solutions, like fuel cells, have low financially rewarding factor, which cause whole projects to be unprofitable. Foregoing circumstances force engineers to find less usual ways for improvement energy efficiency, which will cause extending the time and range of flight. One of them is a tiltrotor.
Tiltrotors are hybrid solutions – they combine airplane and multirotor capabilities to achieve features, which exclude each other in classical constructions. Aircraft-like wing make it able to use its lift-to-drag ratio to achieve energy savings, higher top speed and extended range in comparison with multirotors. UAV is also equipped with multiple multirotor-style engines with additional capability to rotate itself in pitch. In horizontal engine position, vehicle behaves like classical multirotor – allowing pilot to hover and perform VTOL manoeuvres. When engines are tilted to vertical position, whole UAV get performance similar to airplane – high speed and flight endurance.
In the other hand, practical implementation of tiltrotor solution can be problematic: simulation, steering and controlling such aircraft in transition state are complex tasks. Moreover, designed aircraft should follow major rule connected with multirotors: Should have as simple, robust mechanical design as it can.
Proposed article will concentrate on concept and preliminary design of fly-by-wire steering system with unique properties for tiltrotor. One of such properties will be unification of steering method – which eliminates need for switch and setting initial conditions for control subsystems, when flight procedure requires changing flight mode. Second important improvement will be possibility to use transitional states as intermediate state between propeller driven fly and gliding – which allow achieving wide spectrum of flight speeds.
Moreover, huge number degrees of freedom (at least 9) create new opportunities for steering optimization. Extensive thrust vectoring abilities of such UAV could not only implicate substantial efficiency improvement of multirotors, but also improve its manoeuvrability.
The article will focus on basic concepts of kinematics, steering of such UAV and show proposition of energy-usage oriented optimization for its control trajectories. To let mechanical design be simple, all control and steering methods will be implemented in software, which will implicate complex structure of steering system. Overcoming complexity of software should be profitable in relation to expected improvements of UAV capabilities.
References 1. Liu Cuifang, Feng Xuexiao. Mining of Gas Path Fault Residuals Parameter Deviation for Small Uav Rotorcraft Engine. Report of science and technology, 2016,32(10):184-187. 2. LIU Yang, HAN Quan-quan, ZHAO Na. Design and realization of ground synthetic monitor and control system for UAV . Electronic Design Engineering,2016,24(14):110-112. 3. Chen Shao-qian, WANG Xiang-xin, XING Xue-chu. The Egli Antenna System in the Application of the New Type of Unmanned Aerial Vehicle Development. Science Technology and Engineering, 2015,15(7):205-213. 4. He Hai