Dynamic characteristics of beams under free vibration using the smartphone—laboratory experiments for education

Abstract

Studying the dynamics of beams is considered an indispensable field for mechanical and civil engineering students. This paper describes, in detail, the use of smartphones in educational practical works to determine and examine the dynamic characteristics of beams subjected to free vibration. Where the smartphone is equipped with a mobile application to acquire the vibration data of the given beams and store it for processing. Three cases have been discussed, in which three types of boundary conditions have been presented. Also, a discussion was presented to show the influence of boundary conditions and material/geometrical properties of beams on the vibration damping of the system. In addition, some recommendations have been stated regarding the data collection and the processing step to mitigate the measurement errors. Experimental results show an agreement with theoretical results regarding the natural frequency and equivalent mass of the beam system which make the smartphone an alternative instrument to teach dynamic vibration of beams in case of the non-availability of professional equipment.

Dynamic study of pendulum systems through smartphone-based laboratory experiments

“…Therefore, if the period of oscillation of the pendulum is accurately known, it can be considered to determine the acceleration due to gravity by applying equation (3).…”

“…The study of pendulum systems is considered one of the main subjects concerned with laboratory experiments [2], which is a necessary subject for physics students, especially for mechanical and civil engineering students inside the dynamic vibration of structures [3]. However, sometimes students cannot achieve a complete comprehension of some dynamic phenomena based just on theory lectures, such as harmonic motion, trajectory, and energy concepts in some mechanical systems.…”