INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 5, ISSUE 07, JULY 2016 ISSN 2277-8616 65 IJSTR©2016 www.ijstr.org Development Of Translational Motion Of Unmanned Aerial Vehicle Using MATLAB Thwe Thwe Htoo, Maung Maung Latt, Zaw Min Naing, Win Khine Moe, Hla Myo Tun Abstract: This research work describes the translational motion analysis of unmanned aerial vehicle (UAV). Since the center of mass of the receiver is time–varying, the equations are written in a reference frame that is geometrically fixed in the aircraft. Due to the fact that aerial vehicle simulation and control deal with the position and orientation of the UAV, the equations of motion are derived in terms of the translational and rotational position and velocity with respect to the aircraft location. The formation relative motion control is a challenging problem due to the coupled translational and rotational dynamics. As the translational vector depends on the current attitude and its angular velocity, and some of the attitude constraints also couple the position and attitude of the spacecraft, it makes the formation control problem high dimensional. This work develops UAV stability conditions, including translational vector maneuverability condition and included angle condition between the translational and the rotational motion of UAV system, and then presents two methods to calculate the UAV attitude. Both of the two methods need first design the optimal trajectory of the translational vector, and then use geometric and nonlinear programming methods to calculate the target trajectory. The validity of the proposed approach is demonstrated in a UAV by using MATLAB. The performance of the translational motion control is evaluated by the simulated results. Index Terms: UAV, Aerospace Vehicle, Translational Motion, MATLAB, Stability Analysis. ———————————————————— 1 INTRODUCTION THIS complete description of aerospace vehicle dynamics consists of the translational motion of a point on the vehicle, and the rotational motion of the vehicle about that point[1-2]. When there are merely interested in the trajectory (or flight path) of a vehicle, it can disregard the rotational motion of the vehicle and confine our attention to translation. Reducing the vehicle dynamics to the motion of a specific point on the vehicle is tantamount to approximating the aerospace vehicle by a point mass, or a particle. A particle can be defined as an object of infinitesimal dimensions, which occupies a point in space. Consequently, the position, velocity, and acceleration of a particle are each determined by only three scalar quantities; thus a particle has three degrees of freedom. No physical object fulfills the precise definition of a particle[3-4]. The particle is thus a mathematical abstraction, which is used whenever there are interested in studying the path of a physical object, ignoring its size and rotational (or angular) motion. A baseball can be regarded as a particle, if there want to study its trajectory from the time it leaves the hand of the pitcher, and prior to its reaching the bat, provided that ignore the dimensions of the ball and its spin. However, the particle approximation of an object gives an incomplete description of its motion. For example, ignoring the size of the baseball will prevent there from studying how closely the bat misses the ball, or whether the bat hits the ball squarely in its middle. Furthermore, the ignored spin of the baseball would be quite important not only in its interaction with the bat, but also in the deviation of its trajectory caused by aerodynamic forces. Hence, a particle approximation will be inadequate if the baseball’s motion is to be accurately simulated[5-6].. 2 A TMOSPHERIC AND SPACE FLIGHT The study of flight is traditionally divided into two categories: atmospheric and space flight mechanics. The two have evolved separately over the last century. The advent of sustained, powered flight through the air began in 1903 with the Wright Flyer, whose main purpose was to fight gravity through the thrust of its engine and the lift produced by its wings—both aerodynamic in nature—in a controllable fashion. As atmospheric flight progressed over the decades, a new methodology was developed for its analysis, largely based on the study of aerodynamic forces and moments. In contrast, space flight, which required neither lift, nor aerodynamic thrust, was contemplated using the theories of astronomy and ballistics[7-8]. Fig.1. Elements of Airplane Configuration The atmospheric flight vehicles are especially adapted for low aerodynamic drag and can be classified into lifting vehicles (or aircraft) and non-lifting (or ballistic) vehicles. Lifting vehicles derive their support (lift) in air using either static or dynamic interaction with the atmosphere. In the former the aerostatic category lie the hot-air balloons, blimps, and dirigibles, while in the aerodynamic lift category there have the airplanes, gliders, and rotorcraft (or helicopters). The airplane is a versatile atmospheric vehicle, consisting of fixed wings, fuselage, nacelles, and empennage (or stabilizing and control surfaces such as tail , canards, and fins), elevator , ailerons, and rudder, as depicted in Fig.1. While the wings produce the aerodynamic lift, the payload, crew, power plants, and fuel are housed in the fuselage and nacelles, and the stabilizing surfaces maintain the vehicle in a stable equilibrium, and provide control for maneuvering[9]. An airplane possesses all the features that are found piecemeal in other atmospheric flight vehicles. For example, a glider is an airplane without a power plant, while a helicopter has rotating—rather than fixed—wings. The ballistic category of atmospheric vehicles includes missiles, launch vehicles, and entry capsules. Some missiles and launch vehicles incorporate fins as aerodynamic