Now enrolling
Hoverboard Capstone
Rebuild a board, power train up
- Where
- Hyde Park, Chicago
- Format
- One on one, weekly
- Start
- Rolling, once your session time is set
- Open slots
- One Tuesday and one Saturday
- To schedule
- Email admin@mmeg.us
- Length
- Ten weeks
- Cost
- $1,000, parts included
- The board
- Bring a used one, or we supply it
- You keep
- The board you rebuild
Do I need experience?
No. The course starts from nothing and assumes no prior work on vehicles, batteries, or circuits.
How often does it meet?
Once a week for ten weeks, one on one, at a time set with each learner. Every session builds on the one before it, so missed weeks are hard to make up.
What should I wear?
Closed-toe shoes and clothes you can work in. There is cutting, joining, and soldering.
Is the shop work safe?
Live cells, welding, and riding are supervised, and none of it starts without a signed safety agreement.
What does the $1,000 cover?
Every part you fit to the board: cells, pack, motor, controller, enclosure, and the consumables you use up. There is no separate materials fee.
Do I need to own a hoverboard already?
No. You need a used board to rebuild, so bring one if you have it, working or not. If you do not, we supply one and the fee covers it.
Do I keep the board?
Yes. You take it home at the end, and it is yours to extend.
Authored in the course module, and taught the same way to every group
What the course contains, in order
Write the spec
Before anything comes apart, you write down what your board should do: rider weight, top speed, range, and the grades it has to climb. The board you started from almost certainly does not meet it, which is the point. Your finished board is measured against the page you wrote.
Batteries, starting with a lemon
Build a cell out of a lemon, zinc, and copper, then measure it properly: voltage, current under load, and internal resistance. Working out how many it would take to meet your own spec is what introduces current as the real constraint on a pack.
Choose the motor
Compare hub motors with the same power rating and different Kv. One climbs better, one is quicker. You pick for the spec you wrote, and say why.
Choose the controller
Voltage window, continuous current rating, and whether the controller will take an external setpoint fast enough to balance at all. This decision sets how many cells your pack runs in series.
Design and build the pack
Choose a chemistry and defend it against the alternatives, work out your series and parallel counts, and rehearse the joints on dummy cells before building the real pack. Live-cell work is supervised and gated.
Build the battery enclosure
Your pack needs a housing that holds it in the board, keeps it from shifting, and protects it from impacts and water. It comes after the pack because the pack you actually built sets the dimensions, and it has to fit the shell of the board you started from.
Balance and sensing
A gyroscope on its own drifts away from vertical. An accelerometer on its own picks up every vibration. Combining the two into one usable angle is what lets the motors hold your board upright.
Tune, ride, and iterate
Tune the control loop with yourself on the board, since a board tuned empty behaves differently under load. Then ride it, work out what you want to change, and change it. You take it home at the end, and it is yours to extend: lights, a microcontroller that plays music above a set speed, or whatever else you decide to add.
Authored and addressed to one part in the record: Hoverboard pack
The first wrong idea the course takes apart
What a shop floor says
A battery is a tank. You fill it up, it holds the power, and when the board stops it is empty.
What the meter says
At the 26 volt cutoff the pack is still holding volts and still holding charge. Empty is a decision the controller made, not a chemical state, and a pack the board calls flat will still start a fire. The number that decides whether you can climb is not the 4.4 Ah on the wrapper. It is how far the voltage sags when you ask for 19 amps.
Generated from MMEG's corpus record of the hoverboard pack, by the renderer at 69ccf7e. Nothing in it is typed on this page.
The pack inside the board
This is the record a technician works from, as it stands today. It lists every part and every reading the pack should have. Where nobody has taken a reading yet, it says so instead of filling the gap.
7 parts, 10 things to measure, 0 measured.
Battery hazard Every part in this record sits inside the pack, so all of it is battery work.
Source for every part: the typical pack, not a measured unit.
| Part | What to measure | Reading |
|---|---|---|
| Hoverboard pack | Mass, grams | Unmeasured |
| Cell array | Mass, grams | Unmeasured |
| BMS board | Mass, grams | Unmeasured |
| Part number | Unmeasured | |
| Charge port | Connector type | Unmeasured |
| Pin count | Unmeasured | |
| Charge port test point | Signal | Unmeasured |
| Discharge port | Connector type | Unmeasured |
| Pin count | Unmeasured | |
| Discharge port test point | Signal | Unmeasured |