First post here so please bear with me, I could really use some help in this...
Emax 1804s (or 6s, not sure)
Emax 20amp esc’s, Simon K
Mini APM 3.1 (APM 2.6 but actually still had the compass attached…I cut the jumper trace)
Spektrum DX8, Lemon 6ch receiver
Latest Mission Planner
My new Mini APM 3.1 250 quad motors won't spin up after arming, they sort of rough idle, and one motor spins up EVENTUALLY when i move the throttle to high. Outside of that, the motors do not respond to throttle movements.
The machine, which I just finished with new APM Mini 3.1 bought from Ebay, was flying okay but I had problems with Alt Hold where the quad would yo yo up and down hunting on Alt Hold. The think that got me monkeying with a flying setup was related to Alt Hold…every time I lowered the P factor trying to clear up the yo yo, the number I set for P became my new upper limit in Mission Planner. In other words, I couldn’t put Altitude Hold P number back up to the default of 1.000 . Trying to resolve this, I cleared the Mini APM’s eeprom via the Arduino IDE and reinstalled Arducopter 3.2.1 via Mission Planner.
After re-installation, I ran the Mission Planner wizard (and subsequently manually set the quad up on other troubleshooting attempts) and everything looked fine but I could not get the motors to spin past a ragged idle except for one motor which would eventually spin up, sounding rather rough, and would seem to respond to attitude changes on the quad.
What I’ve done to try to troubleshoot/fix:
1. Cleared eeprom and reinstalled APM several times, sometimes going back to previous version of APM to see if that would work to fix the problem.
2. Always re-calibrated transmitter.
3. Always re-calibrated the ESCs.
4. Checked to see if know problem exists where Throttle Max is set to 80 vs 1000 as some builders have noted.
5. Switched out batteries in case one was too low voltage.
6. Scoured the web for a solution.
7. Reviewed the Parameters and PIDs to see if there was something I’m missing. (Not sure I’d recognize a problem here though.)
8. Ensured that failsafe(s) weren’t set to try to eliminate their influence.
9. Always set up flight modes: stabilize, alt hold and loiter (mainly out of habit, will try no modes later tonight when I’m at it again).
10. Made myself a stiff drink and contemplated the time I’ve wasted troubleshooting issues like this on numerous multirotor builds (to include: KK2, Flip32+, CC3D, Crius AIOP, APM 2.5).
11. Went to bed way too late in frustration and despair.
What concerns me:
1. This setup flew reasonably well before I reset the eeprom and re-installed APM.
2. On the flying setup, the fact I couldn’t go above the last figure I set in the Altitude Hold P setting.
3. The fact I don’t see anything on the internet about resetting the board using the “eeprom clear” sketch that is part of the Arduino library of example sketches in the Arduino IDE.
Q: Is this ill advised? I’d think all I was doing was “clearing the decks” for a fresh APM install in doing that.
4. The fact that no matter what I do, I ALWAYS get the same result, the motors give a ragged idle no matter the stick position, with only one motor eventually spinning up, albeit sounding dodgy.
5. These clones are truly crap and I’ve over invested in them (I have another APM Mini that continues to fly okay). (For the record, I don’t really believe they’re crap. I get the sense they’re all made in by a handful of sources in Asia and the bigger names get their boards from the same or similar sources)
What I’m hoping for:
1. Someone, with much more insight that me (not at all hard to imagine) to tell me that I’ve missed some simple setting that will fix this.
2. That resetting the eeprom via Arduino is okay.
3. That someone knows great troubleshooting methods/tools to point me in the right direction (I’ve never downloaded or enabled logging, but I’m open to that… I can learn).
4. A miracle.
Any help would be greatly appreciated.
Please let me know what other information I can provide.