Mathematical model of pneumatic launch system with effect of unmanned aerial vehicle, engine and propeller characteristics

Abstract

Despite significant progress in the development of modern unmanned aerial vehicles (UAVs), universal launch systems are not currently used for them. In fact, each UAV project requires its own launcher, which is inefficient in many cases. To evaluate the characteristics of UAV launchers, simple methods are used at the level of analysis of acting forces, but they do not make it possible to correctly select the type and parameters of the catapult for specific tasks. The object of this study was a universal pneumatic launch system for operational-tactical UAVs. The purpose of this study is to select the design scheme and basic parameters of a universal pneumatic catapult for UAVs of the operational-tactical class. The task: to develop and numerically solve a mathematical model of a pneumatic catapult, perform an analysis of characteristics, justify the choice of a design scheme and main parameters of a pneumatic catapult when changing the initial parameters within broad limits. Method of the study. The thermodynamic method was used with the help of which the differential equations of motion of structural elements were compiled and solved for various combinations of parameters. The results. By modeling, the main characteristics of the catapult were obtained and it was shown that for the effective functioning of the launcher, no special pneumatic cylinder piston sealing is required; the air leakage through the gap is controlled due to the short process time even at high operating pressures. In addition, the permissible minimum height of the cable attachment point on the trolley above the block roller was determined below which the loads on the cable and piston increased sharply. Conclusions. The developed model confirmed the versatility of using the pneumatic launcher of the scheme under consideration for operational and operational-tactical UAVs with a take-off weight of 50 to 250 kg, and such a wide range is provided only by regulating the air pressure in the receiver and is not available for other types of systems. At the same time, if the increase in pressure is limited by safety requirements, the possibility of further increasing the takeoff weight of the UAV in the launch scheme under consideration will remain by increasing the diameter of the pneumatic cylinder.

Keywords

• бпла
• стартовий комплекс
• катапульта
• поршневий двигун