Abstract:

Several mechanical devices include various subassemblies that are elastically supported by bodies in motion. If these motions are oscillatory, the elastic link system is alternatively deformed, exerting forces with periodical variation upon the supported subassembly. As a consequence, this system will start to vibrate. The phenomenon, known as transmission of displacements, is particularly important for technical applications, as it can lead to unwanted effects, e.g. the perturbation of the functionality of the supported subassembly, its premature wear or discomfort for the human operator. The phenomenon can be studied by using a simple mechanical model, consisting of a rigid body, connected by a spring and a damper to an element with known, periodical, usually harmonic motion.

The paper presents an educational computer program, developed by the authors, that represents by animated graphics the motion of the above system, highlighting the characteristic quantities of the supported subassembly vibrations.

By varying the input data, the user can observe, in an interactive manner, the effects of the system parameters on the amplitude of vibrations induced by the moving body.

The paper is structured in three parts, of which the first part briefly presents the analytical basis, the second part describes the program, including its user interface and functionality, while the third part proposes a method for integrating the program in practical sessions, as a tool for teaching mechanical vibrations and vibration control in engineering faculties.

Keywords:

Vibration control, harmonic motion, educational software.