"For your LiIon batteries there is simply a two step charging profile as follows:
Constant current - The charger current is limiting set to about 1C or as per the battery specifications. The voltage increases to maintain a fixed current as the…"
"Here is the CAD drawing. I would only use the particular firewall hole pattern that fits the BLDC motor mount but you could do a two nylon screw mount and choose two holes of each pattern. Notice that each radius cut is outside to the part so…"
"Here is the equivalent firewall using only inside radius cuts rather than outside and easier to make using drill bits and hole saws without a C&C milling machine. See instructions on this thread. Jim"
"I use Generic or Auto CAD to design the parts but any CAD will do. Since I don't have a C&C milling machine, I avoid outside radius parts like Forrest makes instead sticking to inside radius designed parts especially for those smaller…"
"An issue using round tubes (my preferred choice) is mounting the motors securely at the end of the tubes. Typically the BLDC motor's shaft sticks below the thin firewall panel mount and the obvious tempting solution is to drill a hole…"
"Using nylon screws works great attaching the motor to the motor firewall on the boom. The prop however must be attached with AL screws or better and thread locked or you will have a prop motor separation.
With a prop separation, the…"
"You do have the baro sensor covered with no light shining on it - right? Even bright room lighting can do it.
Try powering up the APM with a battery and see if the baro altitude keeps rising or stabilizes. If it is rising you may…"
eliminate any chance of sun getting to the APM's baro sensor
check that the stick position is exactly centered during stabilized flight hovering
and that the natural barometric pressure is not changing.…"
"I also got the dreaded "no data flash inserted" on my APM V2.5.2. I checked the regulator for 3.3V and it was fine.
You may want to try the following if your problem is the same as mine.
Remove the APM board from its case
"The problem may have to do with just one motor failing to put out the power called for. Since the autopilot priority is to maintain stabalized flight the one motor causes all the others to put out less power too and eventually a landing.…"
"Wow - a great explanation. Thanks
Now I have failsafe working in theory. But I want to test it using Mission Planner before trying it out. I have a copter using the latest firmware 3.1.3 and MP 1.3.0. Here is the problem:
I flew today for 1 hour 33 minutes and 14 seconds (93.23 minutes) after two previous failed tries. Today I covered some distance and altitudes of well over 100 feet with a rechargeable battery powered multi-rotor in the "Multirotor…"
"I'm guessing that your APM is thinking that a compass is connected but it really isn't. This is just a wild guess with not enough information to go on from you. I'm assuming you have cut the trace and tried connecting an…"