Electric Longboard Design and Fabrication

2020-03-14

This was an open ended design process to build an electric powered longboard with a composite structure and power system design considerations. It introduced the complexity of tradeoffs between power and size complexity, among other things. The build is currently unfinished.

I had another build opportunity after the snowboard experience. It would involve composite lay up methods as last time, but now with a dimension of electronic components.

Approach:

For this project, we had more flexibility in the design than the snowboard build. The design decisions and available options for this project could have a large effect on the performance. We needed to consider the following attributes: structural capability, energy bank storage, component integration, mounting locations, board rigidity, fire safety, performance reliability.

Process:

1. Started with composite layers of wood, fiberglass, carbon fiber into a layup.
2. Vacuum bagged and cured in a mold to give the longboard shape.
3. CNC routed the profile and mounting holes in the composite structure.
4. Formed the carbon fiber bottom cover in a layup and also vacuum bag cured it.
5. Formed and mounted the brackets to hold the outer bottom cover.
6. Soldered and routed the electrical component connecting wires through the board.

Outcome:

Overall, this project involved many engineering design decisions. As with many projects involving powered energy, a lot of time was spent figuring out how to balance the energy needed for performance to the tradeoffs that would bring. Whenever we considered adding more power (batteries), we would come into more and more complex problems. Such as, overheating, space issues in the cover, clearance height, voltage and current concerns.

This project was unfinished due to the pandemic. Here is what was left to do.

Connect and mount the energy bank, mount the drive unit and front wheels, connect all the components, close it up.