Final Project: eTester

My final project for the Fab Academy is the 'eTester', a device for measuring the dynamic elastic modulus of 3D printing filament as well as other material sample types by measuring mechanical resonant frequencies. The idea is to create a device that follows the methodology of ASTM standard 1876, the 'Standard Test Method for Dynamic Young's Modulus, Shear Modulus, and Poisson's Ratio by Impulse Excitation of Vibration'.

The dynamic elastic properties of a material sample can be calculated if the mass, geometry, and mechanical resonant frequencies of the sample are measured. My aim is to program the eTester to compute these variables to enable the measurement of young's modulus, shear modulus, and poisson's ratio. These are all measures of material 'stiffness' , or the relationship between stress and strain. They are important variables in knowing whether your material can withstand a certain amount of force (e.g. imagine if you were designing a chair, table or bridge).

The motivation for eTester is to create a low-cost way to measure material properties of new, local materials. I plan to combine Filharmonic with a method of sample preparation for bio-based and recycled plastics that can be produced in a Fab Lab. Once generated by the Filharmonic, the data on these new materials can be uploaded to modelling software to allow anyone to design and simulate with new materials.

Visit the sections below to explore my design journey, fabrication process, and final project showcase