DIY Electric longboard controller

Hi Everyone, I’m in the final stages of my electric longboard build after working on and off for the past year. My parts list is as follows:

4x - 3s 5000mAh Lipo battery wired in series for a total of 12s
RotorStar 120A HV (4~14S) ESC https://hobbyking.com/en_us/rotorstar-120a-hv-4-14s-brushless-speed-controller-opto.html
Turnigy Aerodrive SK3 149kv Brushless Outrunner Motor https://hobbyking.com/en_us/turnigy-aerodrive-sk3-6374-149kv-brushless-outrunner-motor.html

For the remote I have an Arduino Pro Mini 3.3v sending a PWM signal to the ESC. With some brief test code I can run the motor and change speeds from a potentiometer in my test setup. However, this is while having the Arduino powered from a USB cable to an FTDI breakout board responsible for programming the Arduino. In my final setup I want to power the Arduino from a 3s lipo battery and a 3.3v regulator separate from the batteries running the motor. When I wire this configuration, the motor will not arm or make any noises, indicating that it is receiving the PWM signal from the Arduino. Trying to diagnose the problem, I have tried many different power sources including 9v battery, 18650 cells, and the balancing leads from the batteries powering the motor(all of these tested to the RAW pin on the arduino and additionally to the 3.3v regulator and the vcc pin) and none of these will run the motor. The only configuration I can get the motor to run is from a USB port(either from computer, iPhone charging brick, or power bank) to the FTDI breakout board and then finally to the Arduino.

I have tried everything I can think of to fix this issue but I can’t figure it out. Any advice would be greatly appreciated!

My second issue arrises when I try to use the Nyko Kama wireless wii nunchuck to control the board. The control is now very unreliable, only sometimes arming the motor and controlling it, other times nothing will happen at all and I will have to restart everything. Also, when it does work the acceleration is very jerky and it seems the motor will get choked up sometimes. Has anyone had success using the Nyko Kama to control their board? If so what nunchuck library were you using and what did your setup look like.

Thanks for reading this! I could use any help I can get. I’m trying to get this board up and running in the next 3 weeks so I can use it to get around at college.

Please post a wiring diagram (not Fritzing) and follow the instructions in the "How to use this forum" post.

In my final setup I want to power the Arduino from a 3s lipo battery and a 3.3v regulator separate from the batteries running the motor.
When I wire this configuration, the motor will not arm or make any noises, indicating that it is receiving the PWM signal from the Arduino.

Grounds connected?
That's the first thing that comes to mind when there are two power supplies and things aren't working.

You should post a photo of your setup. Because I like looking at electric skateboards. :slight_smile:

The wireless controller may be drowned out with EMI from the ESC and motors if you've not
paid attention to shielding things and siting the RX antenna away from noise sources.