The Formula SAE is a student design competition organized by SAE International (previously known as the Society of Automotive Engineers, SAE). The goal is to design and manufacture a Formula-style race car under strict regulations, where ingenuity counts as an advantage within narrow margins. The prototype race car is evaluated for its potential as a production vehicle. Each student team designs, builds, and tests a prototype based on a series of rules, whose purpose is both ensuring on-track safety (the cars are driven by the students themselves) and promoting clever problem-solving.
Each team of Formula SAE is made up entirely of active college students (including drivers).
Composite materials, elaborate and expensive machining projects and rapid prototyping are used as weight-saving strategies. Furthermore, 3D printing enables the students to iterate parts continuously while controlling costs. The cars are tested and qualified according to their safety, design, maneuverability, performance, and acceleration. Particularly, the jury looks for improvements with regard to tests of previous components to be able to see the advances and the ingenuity of the equipment.
The ITBA (Technological Institute of Buenos Aires) located in Buenos Aires, Argentina is a renowned university throughout Latin America and the world. The ITBA team led by Prof. Juan Zubiri (first on the right) has been competing in the SAE FORMULA for some years and in 2018 achieved second place in the Brazil competition.
The team of mechanical, electrical, and electronics college students work informally on the project, receiving support from various sponsors. Students build and test the SAE vehicles directly at ITBA premises, equipped with water cutters, CNC, lathes, 3D printers, as well as fatigue test machinery.
At the time ITBA introduced the Kodak Portrait 3D Printer, the team was facing a redesign of the components of the wheel hub and the spindle, as formula SAE fosters the development and improvement of the parts instead of their replacement.
The first challenge was to optimize and reduce the weight of all components of the wheel hub and the spindle, taking into account how all of these components interact with the wheel, suspension, brakes, hydraulic brake wiring, and steering. 3D printed prototypes helped confirm that all redesigns of these parts operated together correctly.
The team began with the components of the wheel hub and bearing support to make the first dimensional studies of the part. Then, the team placed them in the chassis of the car to examine fit with other components.
After only two iterations, the 3D printed parts were validated.
To withstand the slight friction generated by the interaction of the moving components, the parts were printed in ABS. As ABS is a material that tends to shrink slightly after being printed, a percentage deviation was calculated and the part scaled.
Models were prepared using the Kodak 3D Slicer with the preset material profiles. Thus, students only needed to position the model on the print bed and select the desired material profile, this process simplified the learning curve by avoiding the need for extensive knowledge of 3D printing settings.
The magnesium rim is a delicate component; the printed parts allow for rapid positioning and verification of design aspects without the need to risk hitting or scratching the part with metal components.
These parts were mounted on the vehicle along with all components such as the wheel, brakes, suspension, and chassis. It was verified that the movement was adequate in all axes of work of the vehicle and the parts did not clash with each other. This allowed the validation of the model which could finally be sent for production by CNC machining.