Built a test jig for controller tuning -- chaos ensues

A project log for TeensyFlight36

Writing a flight controller. Follow my progress @

Jacob DahlJacob Dahl 09/20/2019 at 05:140 Comments

I need to tune my rates controller, so I decided to build a jig. I ran by home depot and collected some supplies, and then stopped by Mark Sauder's house and he let me borrow some tools to create the jig, thanks Mark! Eager to get these controllers tuned and to use my newly built jig, I modified the code to only enable pitch rate control. Not knowing a good starting point for my gains, I chose P = 0.001 and left everything else at zero. As soon as I armed, the quad immediately started spinning around the dowel, promptly flinging the RC receiver off the breadboard. The kill switch on my controller is the only way to kill the motors. I stood there panicking for about 20 seconds as I watched it go round and round, the dowel visibly weakening with every violent rotation. I finally grabbed my nearby notebook and shoved it into the action. It took a few seconds to subdue the thrashing, but I was finally able to grab the battery and cut power. 

Needless to say, the dowel on the jig snapped and my notebook is torn to shreds. I lost a diode on the FrSky while reworking it, so I fixed it by just shorting the pads. Thankfully everything still works, so I'm ready to try again tomorrow once I buy a new dowel. 

Lesson of the day: strap down the damn receiver!!! (and write a better failsafe for drivers that crash..!!!!..@#!!)

Update: I had motor wires 1/2 and 3/4 reversed. Doh.

11:03 PM