Training tomorrow’s engineers through a practical challenge in mechanical engineering
How can a system be developed that cracks walnuts whilst efficiently separating the kernels from the shells? Third-year mechanical engineering students at INSA Strasbourg took on this challenging task as part of their project on the sustainable design of mechanical systems.
Beyond the technical challenge, the project aimed to present budding engineers with a real-world industrial problem: developing a solution to make the daily work of a craftsman who processes large quantities of walnuts easier.
From design to eco-design development
The participants were divided into eight teams of six students each and began by working on the design phase. Each group developed a complete solution, including CAD modelling, manufacturing drawings and the necessary dimensional calculations.
The eco-design perspective also played a key role in the project. The students assessed the environmental impact of their technical decisions in order to integrate sustainability considerations into their future professional practice right from the start.
Among the concepts developed was an initial design based on a crushing system. This involved placing a cone fitted with blades inside a cylinder, the operating principle of which is reminiscent of a pepper mill. An adjustment mechanism allowed the size of the resulting fragments to be adjusted in order to optimise the separation of the kernels.
A second approach was based on the behaviour of certain bird species, which crack nuts by dropping them onto hard surfaces. Initial trials confirmed the effectiveness of this method and demonstrated its potential for implementation in a machine-based application.
From idea to reality
In the second semester, several concepts for production and testing were selected. This phase enabled the students to recognise the differences between a system developed on a computer and its physical implementation.
The teams were expanded for this phase, which involved tackling challenges relating to project management, team organisation and the coordination of technical data.
The students were able to count on the support of industry partners to ensure the project’s success. The structural profiles were supplied by Robotunits, whilst standard components from norelem were used to assemble and implement the various systems. Through this collaboration, the participants gained valuable insights into the use of standardised industrial components, which are widely used in professional mechanical engineering projects.
The specific components were manufactured on the conventional machines in the mechanical workshops at INSA Strasbourg. This enabled the students to gain practical experience in manufacturing and assembly.
A valuable learning experience
Even though the prototypes developed are not yet fully functional, the project has fully achieved its educational goals. The students went through the entire development cycle of a mechanical system—from needs analysis to prototype testing.