Hi JB - hijacking your conversation to add my 2c
Cutting the remote antenna was NOT enough for my setup to stop a runaway condition, despite programming in the fail-safe to the control system. Cutting the power to the receiver seems to work, and PM has outlined that he has this implemented. I don’t like it and am not convinced it will be reliable.
Consider having the disconnect leash cause a forced voltage to the ESC signal. This idea could be implemented in many ways.
I’ve not really concluded about how I will apply this to my build but I imagined that I would cause a leash disconnect to to de-energize a relay that would both open and close a circuit, with the latter bridging the earth and signal of the ESC input. One assumption here is signal=ground is a request to the ESC to not run the motor and works perfectly. I don’t know this to be true, yet.
The system may be made more reliable with the addition of some secondary circuit. My thinking is to come up with something to do that also triggered by the leash.
My most wacky idea for a secondary measure is a rudder - the idea to go in circles if the leash is pulled and the esc-cut/esc-ground feature of the leash does not work. Though, there are so many reasons not to do this. If implemented poorly you’ll have some unintended dismounts. Also really complicated to implement on the drive unit. I have an ulterior motive for this crazy idea though, I want a rudder setup for steering & attitude trim should my much anticipated foiling experience suggest it is worth it!
I would like to make another note about the reliability of the control system. My UBEC failed in testing and even with the signal-loss failsafe programmed in the motor went nuts. I highly recommend running the UBEC from a low voltage source (1 battery) or better yet in my view, a separate high capacity 6-12v battery that powers the receiver circuit directly. Two of these could be paired with an appropriate circuit to provide supply redundancy.
Currently I have:
- Leash cutting the receiver power; intend to change this to force a specific voltage to the ESC signal (ideally bridging gnd and signal since that wouldn’t rely on any power supply)
- NO UBEC 6V nominal 2AH receiver battery; am testing a fail-over circuit for the receiver as noted above