trajectory simulation

Satellites weighing 1-10kg are known as Nano-satellite. With the advancement of technology and the smaller parts of the electronics, satellites become smaller and lighter every day. Due to the advancement of technology, the use of CanSats/Cubsats have become more prominent. The optimal and low cost of launching these satellites is air-launch-to-orbit method. The conceptual design and simulation of the trajectory of an air-launch-to-orbit rocket vary based on the type of aircraft, the technology available to make the rocket engine, Aircraft’s velocity, Starting Altitude, Initial (the aircraft’s) Flight Path Angle and Latitude and Longitude, with changes in each of these parameters as a new design. In this research, the feasibility study of air launching vehicle to deliver a 10kg Nano-satellite into a parking orbit using the F-4 aircraft has been performed natively. For this purpose, the conceptual design of the air launch-to-orbit rocket has been achieved after five design stages. The final design is based on the downscale of the single operating sample, weighing 2270 kg, length 6.6 m and diameter 0.65 cm. Simulation of the ascent trajectory has been done using a 3DOF code and validated by Pegasus trajectory modeling.

The major purpose of this paper is to illustarte of statistical design accuracy using trajectory simulation for launch vehicles design in conceptual design phase and also sensitivity analysis of velocity relative to effective external forces. Considering the advantages of statistical design to prevent the time and cost losses, system specification of sample launch vehicle calculated based on statistical data of the studied population. Then, by solving the equations of motion, design parameters are calculated in such a way that difference of the final velocity of trajectory simulation and needed orbital speed is less than 1 percent. Studied launch vehicles are two-stage liquid propellant vehicles, with Portability 2.5-3.5 tons mass to the low earth orbit. To validate, curves of speed, altitude and angle of path of launch vehicle designed with statistical method, compared with curves of Tsiklon launch vehicle, therefore correct operation the mission and accuracy of the statistical design algorithm is proved. By comparing ideal speed and speed of simulation, speed changes of any effective force obtained. Eventually speed loss factor at each stage and sensitive percent of each stage speed relative to the force, for both launch vehicles, statistical design and tsiklon, is analyzed.