Electric Longboard Mark II (In-Progress)


Introduction: Electric Longboard Mark II (In-Progress)

**********As of August 18, 2017***********

After getting my ass kicked in college for a few years and finally finishing up my physics degree, I am about to start an actual engineering education in parallel with stepping down on the metaphorical gas pedal of this project.

First and foremost, I am trying to build a small community around this project. There are many areas where an extra hand can help tremendously, therefore I am publishing all of my progress on my github page: https://github.com/lolomolo/LongboardMarkII

P.S. I'v posted some pictures of what I have made so far over the past year or two.


After gaining some confidence from a working first prototype (see Mark I) I am making some major upgrades. Inspired by the erganomic design, but daunted by the price of the Boosted boards, I have decided to explore the full potential of the electric longboard.

Warning ---

  • This is not a complete guide as the board is still in progress.
  • This project has (and will have) a lot of parts to it and will take an estimated 4 months to complete (mainly because I dont have too much free time due to classes).
  • The vocabulary and terminology I will use wont make much sense to you unless you have done considerable digging and research on your own.
  • This project is expensive (although hopefully still less than a boosted).
  • Do everything at your own risk, this is only a general guide, not meant to be replicated.

Suggested Prerequisites

  • Basic electronics know-how
  • Circuit Theory
  • THIS BOOK!: Practical Electronics for Inventors by Paul Scherz (its a fun read and got me started from absolute 0)
  • An Oscilliscope (you can find 20Mhz+ scopes on ebay for ~$50, this is more than enough)
  • A soldering iron (Look for one that you can set the temperature on)
  • PCB CAD software (eagle is good enough)
  • ~$500 to work with
  • Basic Cpp programming (for arduino or other micro-controllers)

All of this took me about 8 months to learn. Before last spring (~march 2015) I had close to no knowledge of electronics, I barely knew what a capacitor was. (I will make a list of all reading material that I went through)

Again, I anticipate for this to be used as a general guide and not step by step instructions, I will try to brush up on most of the mistakes that I made, and mess-ups that you can avoid.

Step 1: Breaking It Up

Since this is such a large project, the most practical and efficient method to tackle it is breaking up into parts... and those parts into more parts.

From the start I split the project into # parts:

Motor Driver

  • 3 phase half bridge (since the motors I plan on using are 3 phase BLDC)
    • Gate drivers
    • PWM control
  • Microcontroller to adjust PWM delivered to the phases of the motor.


  • I opted for LiFeO4 batteries (lots of power per volume/weight, and they maintain capacity over many more cycles than standard LiPo batteries)
  • Lithium batteries need a battery management system (BMS) that will make sure that each cell charges evenly and none of them are over-discharged.
  • We need a charger that can output significant power (looking at max pull from a 10A wall outlet which is 1200W)

Receiver/Transmitter (the remote)

  • Throttle/Break
  • RF communication


  • For now I will use the chassis from the Mark I board.


  • Different chips need different voltages so we need a converter that take the ~40v from the batteries and output constant 3.3/5/12v
    • Buck Converter
  • Head lights for night riding
  • USB charging port, cause you never know when my your phone gets low
  • Underlighting, cause why not.

Step 2: Bare Bone Motor Control/Power Subsystem

The first thing I did was to make the bare minimum to get a single motor running.

I designed a Power Bridge module that contained 3 buck converter ICs. I designed it to output 3.3, 5, and 12 Volts but after designing and ordering the PCB I change some of the chips I planned to use and no longer needed a 3.3v output. I just didn't solder on the third buck converter.

The 3 phase half bridge used the most powerful and (reasonable priced) mosfets that I could get. Those turned out to be the IRFS7530. I added another stock diode across each body diode (the intrinsic diode in a mosfet) in order to handle the emf that might result from sudden stops of the motor. Also I added pull-down resistors at each gate, however this was a mistake. The gate driver has a built in pull down resistor for each output, and the external pull-down resistors caused interference in other gates and made them turn on during high pulses of current from the gate drivers.

I made the PCB design in Altium designer but have since switched to Eagle because I didn't need the vast amount of tools and complexity that altium provided (its overkill). Eagle is free and I found that SparkFun offers the most comprehensive tutorials.

I had the PCBs manufactured by a website called pcbway. They had the most friendly user interface out of the manufacturers that I came too and turned out to be the cheapest and one of the quickest. They printed 5 copies of both the power bridge and buck converter for 26$ plus 25$ shipping, and delivered in 5 days. The quality of the boards was also on par with many of the local manufacturers.

Step 3: Testing - Gate Drivers

After testing the gate drivers (NCP5181PG) using some random fets that were laying around and shorting/burning and then repairing the buck converter multiple times, I made a circuit to test the full 3 phase bridge. I used the arduino nano to send a 20khz pwm signal (using the PWM1 library) to an inverter (effectively shifting the phase 180 degrees). I used the inverted and none-inverted signal to control the gate driver. However the problem I ran into was that I was getting about 4ns of overlap and since this gate driver didnt have any shoot through protection I was opening both Mosfets at the same time for that 4ns. I figure that wasn't very healthy for them... Although im sure they are fine because they are rated for 1500amp pulses at <10ns. Nevertheless this is extra pressure on the system and a lose of unnecessary power so I ordered a faster inverter and gate drivers with shoot-through protection.

to be continued---

(I am currently learning about ARV programming because I want to move away from arduino and have more control over my electronics).

In the next update I will probably have replaced the arduino nano (which I actually killed a few days ago) with at atmega32.



    • Make it Move Contest

      Make it Move Contest
    • Woodworking Contest

      Woodworking Contest
    • Microcontroller Contest

      Microcontroller Contest

    We have a be nice policy.
    Please be positive and constructive.




    Alright amigos, revamping this project, check out the git repo!

    Are you planning on continuing this build soon? Can't wait to see the result tbh

    Why did you construct a bare bone motor controller if you can buy them cheap anywhere. I mean this is not about controller basics, but a longboard. Puzzled.

    3 replies

    well this is about one-upping the boosted board. (as well as a learning experience for myself)

    You should google for SimonK. That guy did a pretty decent job controlling brushless motors with an Atmel.

    because people can challenge themselves and learn new things instead of buying Chinese stuff

    Really cool