I think I know the answer to this but I'd appreciate a second opinion before stripping down...
Fah Pah ArduCopter kit, ready for first flight, everything working well except occasional 'clicks' from motor(s), can't tie it down to one motor in particular.
I've changed out the bullets on the motor side and are nice and tight now (they were all loose), wiggling wires doesn't seem to have any effect...I didn't change the connectors on the ESC side.
I've attached a mp3 of the clicking, if someone can listen and tell me if it's normal or not that would be a help.
If not normal I'll replace the connectors on the ESC side and get the the Power Distribution board out and have a look at the Deans etc - anything else that I should look at?
Many thanks, Paul
I welded the food of the esc on line, I also will weld on line the wire engine and I will make tests
Hey, I just got my quad in the air a few days ago and I am getting that same "click" sound. It is a bit unnerving. When building the quad I soldered the ESC to motor bullets solid but after a flip today I found a cold solder joint on one of the motor side bullet to wire (possibly caused by me when I soldered the whole thing solid). My quad is tested and "usually" flies well so I'm just going to remove the bullets completely. One less thing to worry about, until I have to take it apart again. LOL! The ESC power wires are also soldered directly to the Power Distribution board.
I'm building my new Arducopter and I have the same issue on my motors. I have to test which Esc is responsible.
This type of click sound is rather normal. Different ESC's clicks with different pace. It is due fast update rates to ESC. Many of ESC's have 150Hz filter running and it seems that sometimes when filter kicks in this click sound is formed.
Many AeroQuad, ArduCopter etc users have similar clicking sound and it never created any problems. Converting ESC to I2C or uploading FastPWM software on those sometimes removes this click sound due available opensource softwares does not use any filtering and like said, this seems to remove click sounds.
My test quads have always been having this same sound, freq just changes a bit depending on what flight software I use. Still using my original ESC's on all quads and never had any problems with them. During my hundreds flight hours I've only broke 1 single motor and that was due really violent crash.
(Who says to land upside down with full throttle, 3mm motor shaft cut broken from middle. Just changed motor Bell, rest of the motor is still in active use :) )
I try to hook up signal and 3-phase lines on a logic analyser on somepoint to see what happens during click pulses. If someone happens to have analyser close by. Just go and look it too...
Maybe the quality control of the supplier for the motors and ESC needs to be looked at. I am a full time electronics technician and quite embarrased I did not spot the poor solder joints on the bullet connectors straight away. They visibly look ok, though a bit dull looking. I guess its lead free solder? Only spotted it after i gave a gentle pull on one of them. So far, all 5 motors I have recieved from Fah Pah (4 from the kit and 1 that I bought later) and ESC's have had poor solder connections at the bullet connectors. Not one bullet connector had sufficient insulation stripped off and all needed resoldering. Consequently, I'm a little dissapointed that I did not check the last motor I received. The quad is now wrecked after a 4 min flight.
I would think that if you could place either the main battery leads or one of the motor phases on an oscilliscope you could see if the voltage is spiking. A large voltage spike generated could possible cause a spark/crackle but it would have to be in the order of several thousand volts genrated to break down or jump across insulation/gaps. I have never had that sort of clicking before ever from single esc's running in aircraft and I have had around 30-40 different ESC's and motor combos.
I know that some ESC's allow you to change the switching frequency and the timing, that may help. Also could it possibly be related to some sort of periodic cycle lining up (due to the software loop restarting/resetting? and/or multiple ESC format?) and causing one phase to misfire? If a phase fires out of order a large voltage could be induced or a strong magnetic field could be produced at the wrong time which could be in oppostion to the other magnetic fields, my guess that would try to load/lock the rotor and could make a sound. If you short out a petrol generator for example, the magnetic field locks the rotor so strongly the motor will stop, and large truck mounted genrators can rip free of mounts and destroy themselves!
If you dont have an oscilliscope to look for spikes, what about possibly some sort of strobe you could adjust to see the motor standing still then possibly jumping out of sync after a click? That would at least tell you if it was physically happening to the rotor, or else just an electrical sound.
With changes in loading, I have had magnets clip the rotor, and that is actually quite common, as the magnets are often laid up in epoxy fairly roughly in some constructions. The idea is also to place the rotor as closely to the stator as possible to reduce magnetic flux losses through the air gap, so they are pretty tight tolerances! You will be able to tell if that was the case by pressing out the shaft and inspecting the stator for scuff marks.
Also could it be the prop adapter nut/plastic slipping? Unlikely I know.
Good luck I am very interested to know what the answer will be!
"I have never had that sort of clicking before ever from single esc's running in aircraft and I have had around 30-40 different ESC's and motor combos. "
you're not getting the point: the APM has very fast refresh rates, which you can't get on a normal RC system -> it confuses the ESCs
all you mentioned, it's just that the ESCs are getting out of their timeframe -> they refresh their RPM, nothing bad