A unified educational mobile application to aid in teaching solid mechanics using interactive Mohr's circle

Abstract

The interpretation and visualization of engineering problems are complex. Therefore, engineers have always developed graphic procedures to solve these problems, one technique being Mohr's circle. The study of geometric properties of the cross-sections, plane stress, and plane strain are some applications of such techniques in Solid Mechanics. In practically all literature adopted in undergraduate courses on these topics, the efforts of authors to teach with the greatest clarity are remarkable, using all possible resources in books, with very well-designed graphics. However, concerning Mohr's circle, the mental visualization of some movement is needed, be it the rotation of points on the circle, the rotation of the cross-section, the axes, or the differential element. This need makes such topics ideal to be taught through interactive animations, impossible in books. Computer programs about these subjects do exist, however, with reduced user interactivity. Thus, this work presents a new unified mobile application with several useful interactivity features for teaching plane stress, plane strain, and moment of inertia in engineering courses, using Mohr's circle. The application is developed in Java programming language, using Android Studio software. The graphical environment was developed with the aim of being a didactic and intuitive way to study and learn about cross-section properties, plane stress, and plane strain. The results provided by the application are compared with examples from the literature, presenting accurate responses, with easy visualization and interpretation. The usage of the program makes studying the initial concepts of solid mechanics and Mohr's circle enjoyable for engineering students.