Big Idea: Interior Properties of 3D Objects and Impacts on Affordability and Durability

This activity expands upon activity 3 by going inside 3D printed objects and examining how infill, layer height, and shells can impact strength and cost (material usage). Affordable housing is the primary goal of the 3D Affordable Innovative Technology Housing Project - looking at how 3D printing technology can produce quality affordable homes efficiently at lower cost. It is important for students to understand that affordable housing should be produced at lower cost but should also be just as durable and well-built as any other home.

Students will explore this idea using a simulation built in Scratch. They are tasked with running several simulations by adjusting the number of outer shells, infill percentage, and layer height and documenting the resulting cost and durability. Increasing the infill percentage and number of shells improves durability but requires more time and material, which increases the cost. Time, material, and cost can be reduced by using lower values, but this impacts durability. After running their simulations, students are asked to determine values that provide a balance of durability and affordability.