Hacky Racers, an electric vehicle racing series that’s part of the Power Racing Series, encourages drivers to put together their own hacky vehicle. While it looks like a lot of fun, in order to keep things relatively safe, current powering the car is regulated by an inline fuse from the battery, effectively limiting the top power output to the motor—thus keeping speed in check.

This means that while drivers need some control over how fast their motor is running, traditional PWM control where as much power is thrown to the motor as needed to keep it at a certain speed doesn’t really work. Instead, you need a system that controls how much current is provided. It’s a subtle problem, solved here with the addition of an Arduino Nano, which regulates output based on feedback from a current clamp sensor. While it won’t let a racer exceed the current limit, it does allow for maximum output when needed without tripping the fuse!

Those wishing to learn more can read the full write-up here and check out Hackaday’s recent article.