The CREATE Education Project recently supported an inspirational Bloodhound SSC themed STEM Day organised by the Institution of Mechanical Engineers (IMechE) at Sheffield UTC. Approximately 55 UTC students started the day with an engaging assembly where they were introduced to the Rolls-Royce EJ200 jet engine (used to start Bloodhound SSC) and learnt the principles of how a jet engine works. They were also introduced to Newtons 2nd Law of Motion F = m x a and the principle that the smaller the mass of a vehicle is, the greater the acceleration will be.
The students were split into teams and set a challenge to build and race Bloodhound Balloon Cars. The Bloodhound Balloon Cars are a kit consisting of a lightweight card body, 2 wooden dowel axles and 4 MDF wheels that can be assembled to make the car, which is propelled by a blown up balloon. The heaviest parts in the kit are the wheels, so replacing these with lighter wheels would allow the car to accelerate faster.
After an “Introduction to Manufacturing” session where students learnt about additive manufacturing and the different types of 3D printing technology, the CREATE Education team ran a practical workshop. In this session teams of students were tasked with designing and 3D printing a set of lightweight wheels for the Bloodhound Balloon Car. After brainstorming to identify what factors can affect the weight of the wheel, students were introduced to the concepts of “Infill” and “Wall Thickness” and how these affect the weight of a 3D printed model. They were then shown how to adjust these settings when slicing a 3D model in the slicing software Cura.
Each student then produced a 3D CAD model of their design using Solidworks. Team members reviewed the wheel designs and selected the best design for 3D printing, this was imported and sliced in Cura then 3D printed.
After lunch the teams assembled their balloon cars and fitted their custom 3D printed wheels.
Then came the culmination of all the students hard work, as, following a short testing period, teams were given the opportunity to race their custom balloon cars in a fun competition. Finally to end the day the winning team was selected and congratulated.
In The Classroom
This activity is perfect for schools to run as a STEM club activity or during a STEM day. The Bloodhound Balloon Car kits are available to purchase here. Alternatively the challenge could be extended further so that teams of students design and make their own lightweight model balloon cars. This allows them to investigate the properties of different materials to select lightweight materials or students could design and 3D print the body/shell of the vehicle.