Solar Car Design “Any intelligent fool can make things bigger and more complex... It takes a touch of genius - and a lot of courage to move in the opposite direction.” -Albert Einstein

Keep It Simple!

Key Ideas To Focus On Safety Reliable Efficient Execution Is this safe? Reliable Must first finish the race. Efficient Performance Considerations. Execution Can we do it?

Process Learn general solar car concepts Spends time observing successful executions Read Event Rules! Work on design A lot of design problems and considerations can be solved simply by applying the constraints found in the rules.

Overview Array Position Wheel Layout Frame Suspension Electrical

Array Position A Few Concepts Above Body Body Contour Below Driver's Head/Canopy

Array Position Above Body No Shadows from Driver or other components. Design Freedom below array

Array Position Body Contour Aerodynamic Shaded by General Shape of Car Many Angles to sun

Array Position Below Driver's Head Shaded by any items above array Can be bright for driver Driver is exposed to more direct sun without canopy

Flat Array vs. Curved Flat Solar Arrays Curved Solar Arrays Easier to execute Angle to sun less of a concern Curved Solar Arrays Higher the angle the greater chance for breaks without ideal support. Angle to sun more of a concern Power Tracker Considerations

Hybrid Array Increase overall array efficiency by placing higher efficient cells in most optimal position.

Wheel Layout 3 Wheel 2 in front 1 in front 4 Wheel

3 Wheel Layout 1 in Front Generally less stable Unstable in most turns at decent speed

3 Wheel Layout 2 in Front Generally Stable “Gets it done” Popular

4 Wheel Possibly heavier than 3 wheels due to extra suspension Potential to provide better support and ride Road Debris benefit

Frame Space Frame Tub Triangles Usually welded metal Usually composite Aluminum Steel Tub Usually composite Carbon Fiber Fiberglass Tube-like shapes/sections

Frame Space Must be designed to support all necessary loads

Frame Tub/Composite Lighter Stronger Easier to design Harder to execute Higher cost

Important Cargo Driver Batteries Suspension mounts Array mounts Motor/Motor controller

Suspension Do you need one? Good idea? Not necessarily. Solar Cells are fragile Road Debris Driver Comfort and ultimately Driver Safety

Suspension Types Double Wishbone MacPherson Strut or McPherson strut Popular MacPherson Strut or McPherson strut

Suspension Double Wishbone

Suspension MacPherson Strut or McPherson strut

Electrical All solar cars are electric (battery) cars with an added array. All solar car main electrical systems look schematically the same. Difference is in the details and execution.

Electrical Solar Cars are cars first, battery powered/electric cars second, and solar cars third.

Electrical Power Trackers Converts and optimizes array power for system. Not needed, but a good idea. High cost. Power Tracker for each array string/angle, or one large Power Tracker for the whole array.

Electrical Fuses Switches Specific Fuse Detailed by Event Rules. Add fuses where it makes sense for added safety. Switches Specific Switches Detailed by Event Rules. Add switches when it makes sense for added safety.

Electrical AC vs. DC We're working with DC. Make sure components are DC rated for your application. Contact manufacturer or trusted consultant to make sure your components will work reliably with your DC application.

Electrical Wire Size wire for worst case scenario. Temperature Voltage Current Wire should be capable of carrying more current than fuses at operating temperatures.

Summary Keep It Simple Safe Reliable Efficent

Questions