International Journal of Applied Science and Technology

ISSN 2221-0997 (Print), 2221-1004 (Online) 10.30845/ijast

EXAMINATION OF LATERAL DEVIATION OF A PROJECTILE SUBJECTED TO INTERNAL GYROSCOPIC FORCES
Christopher M. Umstead, Hamid M. Lankarani

Abstract
The need for lateral travel can arise in a simple projectile either due to the target moving or to a transverse external force that moves the projectile. By the use of internal moving parts, a force in the lateral direction can be created, thus changing the flight trajectory of the projectile. Therefore, the possibility of the use of an internal gyroscopic force derivedfrom a rotating disk could be used to counteract such activity. In this study, three internal swing masses attached at the end of a massless rod are located on the points of an equilateral triangle centered about the major axis of the projectile. The rotation of mass generates a normal acceleration and a subsequent force and torque upon the projectile. The force from combined movements of the masses can be used, to a small degree, to control the movement of the projectile. In this study, a model for this movement is derived mathematically and simulated on the computer using a developed code. For the cases examined, the projectile moves cyclically about the axis or deviated with a relatively even slope away from the axis. With these models, a parametric study is conducted with predetermined changes.The parametric study is focused on actuating each mass in sequence or changing the initial weight of the mass and starting position in relation to the projectile. A computer program is createdin MATLAB for the developed model and the equations of motionare generated and solved numerically to simulate the flight of the projectile. The results from the simulation for the project are compared for differences in the projectile physical conditions. The resultsof this study show that the projectile could move in a lateral directionin a controlled manner. But the overall movement is minimal when compared to the size of the projectile or the distance traveled. While this application may not be suited for use in small projectiles, it may hold merit for use with larger craft or re-entry vehicles.

Full Text: PDF