Student Designed Cars
Designed cars are serious business! The best cars weigh less than 400g without ballast, and can reach a top speed of 35km/h in high sun, around steep corners. They will complete a 100m figure-8 circuit in under 20 seconds. The components in these cars can cost in excess of $600 and use some of the best materials on the market - carbon fibre and medical grade motors to name a few.
But don't let that deter you. Most of those components are reusable year to year and second hand components can be found for close to free if you know where to look. The upside is that the Student-Designed Car division is the most advanced and rewarding that Model Solar Victoria has to offer, and develops real skill in Aerodynamics, construction and Mechanical Engineering. At the high end, these cars are precision implements which stay on the track through black magic and glue alone.
Some of the cars' performance comes down to materials, but not much. Some comes down to design, but not significantly. The vast change in performance will instead come in the quality of construction and assembly, regardless of financial resources. The optimisations to be made in rolling resistance and air drag can make many (as in more than 6) seconds of difference, which is all that matters in a 20 second race. Good bearings, an even and low weight distribution, an aerodynamic body and well aligned axles can change a car's time from 28 seconds to 19 seconds, which is a winning time.
As such, it is recommended that students in Primary School start by participating in the junior or advanced boat competitions. they're smaller scale, cheaper and have a lower barrier of entry. However, the Student-Designed Cars are by far the most rewarding for High School students, and those components from boats can be re-purposed for cars. For those of you new to the Advanced Cars, read through this guide carefully. Box Hill High School have an active Model Solar Car program, run through their Faculty of Engineering Technology, and are willing to provide design and material assistance to other schools or students. They have a test track which is erected from early August to the event date. The program operates every wednesday of the school year (including school holidays), and the faculty is often open until 5:00pm every evening. Any students are welcome to come and make use of their track and workshops at these times.
A model solar car is made up of a number of sub-assemblies or design areas to consider. These are all variables in the performance of a car that should be considered:
· Overall dimensions (Regulations)
· Chassis design and materials
· Body shape, aerodynamic form and materials
· Wheel size, number and placement. Location of drive wheel.
· Dimensions and placement of guide rollers, for control
· Motor and ratio of drivetrain gear systems
· Solar panel design, layout and output
· Electronics and other electrical systems
All of these design areas are covered in detail in the following pages.