A code to simulate wood-cracking

Matthieu Noel, PhD student in mechanics at MSME, Université Gustave Eiffel

As part of a collaboration between the Technological Institute FCBA and the MSME Laboratory, PhD student Matthieu Noel has designed a code to model and simulate cracks in wood materials. He is happy to share it with furniture manufacturers, as well as mechanical and civil engineering companies.

Before any product is placed on the market, furniture companies must carry out standardised tests to certify its safety and compliance with commercial standards established by the CEN (European Committee for Standardization). This is the case, for example, with standard EN 747, which applies to bunk beds and high beds. Some of the companies affected by these regulations are turning to the FCBA (Foret Cellulose Bois-construction Ameublement), a technology institute that carries out tests of the strength, durability and stability of wood and wood-based materials, in order to detect deterioration patterns that are common in wood furniture and construction.

As part of his thesis in collaboration with this institute, Matthieu Noel has developed software to model and simulate crack damage in wood materials in particular. It was designed following a series of uniaxial compression tests carried out on spruce samples. They were used to measure the critical force at fracture, identify the elastic and damage properties of spruce and establish a fracture criterion for predicting joint strength in a certain part of a piece of furniture. This digital approach should help reduce the duration and cost of the experimental tests required to bring furniture to market.

Other sectors of industry could also benefit from this code. From the outset, Matthieu Noel ensured that his software would be able to be used in other areas apart from furniture. "My code is based on the finite element method (FEM) and can be used to run simulations that can be useful in mechanical or civil engineering.” Inspired by the philosophy of RDM6, free software that Matthieu Noel used when he was a student at IUT in Le Mans, his code is "flexible, robust and open for use in research". It can be used, for example, to teach FEM to students or carry out rapid prototyping of components for engineers. "Unlike other code available in Python for carrying out finite element simulations, it is accessible to ordinary humans because it does away with complex mathematical concepts," says the PhD student, who intends to create YouTube tutorials once he has finished his thesis.

The young researcher also worked on making his code easy to use: "It was important to me that users who didn't have expert knowledge of programming and mathematics should be able to use it.” As soon as he created his code, Matthieu Noel put this pedagogical aspect into practice. Alongside his thesis work, he teaches first-year mechanical engineering students at ESIEE Paris: "I've used the code to create educational example videos for my classes. In return, interacting with students has enabled me to respond to problems encountered during the design of the code.”

The future doctor has long been interested in open science, appreciating its values of reproducibility, free access and collaborative sharing: "for me, these are the fundamental, characteristic values of ‘real’ science. Open science never sweeps potential errors under the rug and is always open to criticism. It provides access to previous versions with a didactic and collective approach"he says.

Matthieu Noel would like to see software development more widely recognised in the academic world. "Even though, as we have seen with Covid, the progress made possible by sharing scientific data is being considered more and more, there is still a long way to go before the world of research fully recognises the value of IT work and software creation as scientific production.”

Versioning: the ability for users to track different versions of software that are saved. Versioning provides a snapshot of the software at a given point in time. It is useful for checkpoints, error correction and restoring previous versions if necessary.

Finite element analysis (FEA): method used to numerically solve partial differential equations. These equations can simulate the physical world and are frequently used by engineers and scientists in structural, acoustic, thermal science or biomechanical problems.