A Two-Degree-of-Freedom of Motion Mechanical Oscillatory System with Excitation and Limit Cycle Oscillation – Automatic Armament Case

 

Zdravko Banjac

Snežana Jovano

 

This paper presents a numerical analysis of motion dynamics of a two-degree-of-freedom of motion rectilinear oscillatory system with the motion limitations and forced excitation. The analysis of a mechanical-mathematical model with discontinued parameters is based on the numerical integration of differential equations. The forced oscillatory system has been implemented in two automatic armament systems of 12.7mm and 20mm calibres, which have been installed in the light propeller aircraft and transport-combat helicopter. The motion parameters - movement and velocity and forces have been measured on the stand. Motion parameters and force computations were compliant with the analogous values measured on the designed systems. The mechanical-mathematical model of system dynamics can be used for a prediction of the behaviour of a two-degree-of-freedom of the motion system in the stage of parameters adjustment, prior to the design of system elements. The description of the measurement and used equipment is presented as well as a possible way of further work

 

Key words: mechanical system, oscillatory system, oscillatory moving, self-oscillating, eigen frequency, system excitation, forced oscillations, oscillation damping, automatic weapon, 12.7 mm calibre, 20 mm calibre, aircraft armament.