Multibody modelling of an internal gyroscopic micro-mechanism for development of lateral deviation of a projectile

Abstract

The lateral control of a projectile for targeting and impacting a nonstationary target is of interest in many applications. Through the use of internal moving parts, gyroscopic forces can be generated, thus changing the flight trajectory of the projectile. In this study, three small internal swing masses are introduced to the projectile and their motions are controlled. The masses are attached to the end of massless rods that are located on points of an equilateral triangle centered about the major axis of the projectile. A mathematical model for the internal gyroscopic rotating disks of this multibody mechanism and its trajectory path is presented. For this mechanism, the dynamics equations of motion are developed and solved numerically to simulate the trajectory of the projectile. The concept projectile model is shown to move cyclically about the axis of rotation and to deviate from its axis in a relatively even slope. A parametric study is then focused on actuating each mass in sequence or changing the weight of the masses and their initial positions to examine and evaluate the flight trajectory of the projectile. The results from this study show that the lateral deviation of a projectile can be controlled by altering the initial configuration of the rotating mass mechanism. This application may hold merit for controlling the re-entry flight trajectory of air vehicles.