I’ve been driving Dirt 2.0 a lot lately and decided using a button for the hand brake wasn’t ideal. It was time for an analog hand brake. Club Sport makes a really nice one for $120 plus shipping and handling.
Not. Gonna. Happen. I’m too cheap to spend that for something that simple. Time to roll my own.
A nice, home-made kludge would look right at home installed on my crude racing rig… except there’s a mouse platform in the way.
But that’s not really much of an obstacle when everything is made of wood. Ready to start prototyping.
So, where exactly do I want it? Nothing I tried was quite right because I was stuck placing it just a little too far to the right, but this was as good as I could get.
It needs to pivot and return when released. Check.
It needs to connect to a linear potentiometer. Added high tech coat hanger push rod. Check.
It needs a stop so I don’t break the potentiometer by pulling too far. Check.
With the mechanics all working, I wired the pot to an Arduino Pro Micro installed in a solderless prototype board – this was super complicated, all three wires. 5V, ground, and A0 input. Loaded the sketch amstudio used for his handbrake (YouTube https://youtu.be/kv0FTpRLFMY) off github (https://github.com/AM-STUDIO/Analog-E-Brake), et voilà, I have a working hand brake.
Total cost? $12.50. The 10K slide pot was $5.50 and the Arduino Pro Micro $7. Everything else was scrap that was lying around the shop. Well, I had spare Arduinos lying around from another project – they’re so cheap it doesn’t make sense not to order several at a time, so the only thing ordered specifically for this build was the $5.50 10K pot.
Eventually, I’ll build one that’s an enclosed unit, but for now this will do. It could also use a stronger spring and better stops, but it works great.