2025 ASEE Annual Conference & Exposition

This paper is concerned with a state-funded initiative aimed at introducing fundamental concepts of lightweight design to young individuals through interactive workshops conducted at universities and industrial facilities.
The primary focus of the workshops taking place at our university is to demonstrate the varying deflections of cantilever beams with different cross-sections but identical weights under loading conditions. Additionally, they shall highlight how the natural frequencies of bending vibrations are influenced by the area moments of inertia of the beams.
The elaboration of the teaching content and method and the design of a suitable experimental arrangement was entrusted to a team of three graduate students in their first year of an automotive engineering master’s degree program. Their aim was to introduce young individuals to some essential ideas of lightweight design by means of static and dynamic experiments with cantilever beams in an age-appropriate way.
For this purpose, standard profiles were selected that have approximately the same mass per unit length, but different flexural rigidities due to different materials and shapes of their cross-sections. The aim is to demonstrate that the selection of the profiles influences the load capacity of a structure without necessarily changing its weight. These profiles are clamped on one side and loaded by a point load at the free end for the static experiments. Due to the different bending stiffnesses, different deflections are achieved with the various profiles, even though they weigh the same. To convince the participating audience, these beams are to be easily removable for weight comparison.
Another topic of the workshop is the deliberate shift of the natural frequencies of a structure through a suitable selection of the profiles to avoid undesirable resonances while maintaining the weight of the structure. This is demonstrated by carrying out modal analyses with the same cantilever beams as for the static tests. The experiments are performed live in front of the audience by using accelerometers, an impact hammer, and a data acquisition system. As a result, the natural frequencies and vibration modes of the cantilevers are obtained and visualized on a computer screen. In addition, two-dimensional vibrations are also demonstrated in order to vividly visualize oscillation modes in the form of Chladni patterns.
In addition to conceptualizing the experiments, the project team designed a tailor-made laboratory trolley on which all experiments can be carried out. Thus, the experimental setup is also suitable for use in other contexts, such as lectures in mechanics and strength of materials.
This paper describes the didactic approach, the development of the experimental setup and experiences from first experiments.