Studying the influence of external moment and force on a disc's motion

In this work, the influence of a gyrostatic moment vector (GMV) and the Newtonian field (NF) on the rotatory motion of a restricted rigid body (RB) according to disc case around a fixed point is examined. The basic equation of the body motion is used to get the regulating motion's system as well as the three available independent first integrals. The system's six equations and these integrals were reduced to two equations of a quasi-linear two-degrees-of-freedom autonomous system and one first integral. The disc has been presumed to be quickly rotating around one of the ellipsoid of inertia's main axis. Poincaré's method of small parameter (PMSP) is applied to acquire the periodic solutions of the controlling system of the body's motion. Euler's angles are utilized to characterize the body's configuration at any instant in which it is graphed, as well as the obtained solutions to explore the good action of the body's parameters on its motion. The phase plane graphs of these solutions are presented to examine their stabilities. The relevance of this work may be traced to its wide range of applications in fields as diverse as physics, engineering, and life sciences, including assembly and machine design.