Canners 130/180 quad build

While still waiting on that 1 LittleBee 20A ESC, I discovered that the ESC contacts on the Matek PDB only allow for 4 x 20-25Amps. That means if I would buy 30Amp ESC's to go with those 2600kv motors I must replace the PDB also, otherwise the ESC's won't work as well as they should, or the PDB could get overloaded and fried.

I'm still not sure if the current issue with the burned ESC is caused by a simple bad ESC or something else. And as long as I'm waiting for replacement, I can't try it out.

btw, the 130 is coming along nicely, have finally figured out where to put everything, pretty difficult cause it's such a small quad. Already got power on the PDB, can start soldering the rest soon.

Most of the soldering is done. Taranis updated so I could bind the radioreceiver. Flightcontroller flashed with Betaflight.
Now only need to flash/calibrate the ESC's, and the last step will be to get the transmitter to talk to the quad in PPM.

That last part is the most difficult for me, cause I never set up PPM before.
If I can't get PPM to work I'll just order another receiver that works on SBUS, which is the same as previous build.

btw the tiny motors sound awesome
 

I am stuck at the same thing as previous build. Only instead of SBUS, this time I can't get the PPM to work.

Have tried every possible way of connecting the receiver to the flightcontroller. Like with the previous build the receiver is bound to the Taranis. With rangecheck I can see the transmission weakening as I walk away from the receiver, so that works. And when I connect an ESC directly to the receiver I can control it with the throttle. But when I connect via the flightcontroller, no signals are passed through.

It's very possible it has to do with outdated firmware on the receiver, but I'm not smart enough to update it.   https://www.youtube.com/watch?v=2J2he0DrzC0

Oh well, I rather have an SBUS receiver anyway, only that means having to wait a bit before it arrives from China.

I did discover what causes the random motor spinups on my other quad. Because the exact same thing happened with the new one, and it turned out to be a too low min throttle setting in the ESC firmware. Apparently this can happen after calibrating the ESC's with the transmitter, like in this video: https://www.youtube.com/watch?v=OOplk52R4no. After I set the minthrottle value back to default, the random spinups disappeared.

For testing now using the X8R SBUS receiver that came with the Taranis. At least this seems to be working, receiving signals.

It's not flying yet, but this pic will give an idea how it's going to look.

Almost got the 130 ready for first testflight. But still messing a bit with the ESC and throttle calibration. This quad is more difficult to set up then the previous one, but in a way that's good cause now I learn more. From what I learned today I found that maybe the troubles with the 180 also could be solved with some more finetuning ESC/throttle settings. 

Well, I found the definite cause of the weird spinups for the 130, and probably also the 180.

Yesterday all was fine, but this morning I powered up the quad and this fucking problem had returned. After messing a bit it dissapeared, but then came back again. So I figured it had to be a short somewhere. Each time I turned the radiotransmitter off, the problem vanished. Perhaps the receiver or the antenna wires got damaged, so I fiddled those, which seemed to help a little but didn't fix it. I started pulling random wires to see if anything happened. Finally I did find the cause of the short. The problem was a loose connector to the flightcontroller. The protective casing of the flightcontroller prevents the connector from being inserted properly.

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Having that fixed, I'm back to the original final problem I got with the 130. Though maybe it's not a real problem:

https://github.com/betaflight/betaflight/wiki/Frequently-Asked-Questions#why-do-my-motors-keep-accelerating-on-the-bench-when-i-arm-without-props-

I can throttle up and down as supposed to, but when I add input from the other stick(pitch, roll), the throttle tends to get stuck and sometimes even speed up. The throttle stay stuck until I throttle completely down to 0. Which means if the quad was flying it would fall down.

Now that FAQ explains it could be normal, but I'm a bit anxious to screw on propellors with this kind of behavior.

I switched the CC3d Nano flightcontroller with the one from the 180, and got the same results with the throttle issue.
So for now I'm assuming it is normal, and went ahead finishing the build.
Now only need to mount the videotransmitter, then the quad is ready for a testflight.

It hovers!

Tried it out in the garden, and it works.
Have not tested real flying yet, garden is too small for testing.
I need some space, in case it spins out of control. 

Just back from first test flights and overall it flies great. The motors do get a bit hot, but it's hot weather today also. Did have a bit of stuttering or desync on the motors in certain situations(sharp turns), where the motors seem to turn off and on, and the quad loses balance for half a sec, but then quickly recovers. For the rest no troubles at all. I could sort of reproduce the error, so maybe it can be tweaked out by changing the 'motor timing' on the ESC's. These are high kv motors (4000kv), so medium for the motor timing could be too low. Otherwise maybe it can be fixed by adjusting the PID settings. I doubt it's a serious issue cause then I would experience more and random strangeness, but otherwise everything went very well.

btw, forgot about that half tightened nut you can see on one of the pics, I fixed that later.

Changed the motortimings on the ESC's to medium high, but it made no difference.
Now thinking it has to do with the PID settings, cause I remembered it's almost the same as my Eachine did with fast roll+yaw turns in the begining before I started tuning the PID's.
It's like the gyro is preventing the quad from flipping over or something and then gets confused when I roll too much, though I can make wide barrelrolls.
The quad flies suspiciously stable, but the accelerometer is turned off.

At around 30 secs in, this vid shows kind of what happens, though it may not be the same cause.



For the rest it's really fun flying the little quad, it is fast and loud. I'm determined to solve this problem.

Found a few vids on youtube that showed how a desync or bad motortiming sounds and works:





So even though I didn't want to do it, cause it could damage the motors, I tied my quad to a chair and gave it a few short full throttle bursts with props on.
The motors responded perfectly to the throttle, no delay, stutters or whistles. At least now I can exclude it being dsync or bad motortimings.

I almost fixed the weird behaviour of my 130. It's simply a case of bad PID tuning.  

Yesterday I copied someone elses 130 quad PID's to start with. Went flying and noticed some difference, but the problem was still there.
Only this time I started to get a feel for when it happens. After a bit more reading and learning, I tuned the quad some more, and went flying again.
Now the problem is still there, but much less, also flips are tighter and faster.

http://iflyquad.com/2016/01/05/depth-pid-tuning-guide/


At first the motors got very hot, even after a short flight. But after tuning the PID's a little, they stay much cooler.

Quote :

At first the motors got very hot, even after a short flight. But after tuning the PID's a little, they stay much cooler.

That's very interesting to know.

And well done on your detective work,lets hope you can get it flying perfectly soon

Thanks

Not going to be easy to tune the quad to perfection though. Today I changed the PID's a bit more, but the problem was slightly worse again. Most difficult is that I can only tune once on my pc at home, and have to test somewhere else to see the effect.

But now I found this tuning is quite important, I decided to buy the cheapest windowstablet I could find, so that I can tune and test away from home.

eSTAR Beauty 7 inch, quadcore, win8.1 : with all the discount it only cost me 72 Euro

Received the tablet, quite impressive little thing for the cheap money.  
Glad I can finally start learning the effect of different PID settings, and properly tune my quads.

Also bought a new radioreceiver(FrSkyX4R), cause I used the X8R in my 130 quad.
And since the replacement ESC arrived last week, I can now start rebuilding my 180.  

Why don`t you use the x8r ? you can always put it back in the 130 when flying that one.

That would mean I can only fly with 1 quad at the time, with the other being unavailable.
It's not a part that's just slapped on the quad, it's in between other parts, keeping them in place.
Too much hassle having to rebuild half the quad each time I decide to fly with one or the other.
And I like how the x8r antennas look on the 130.

Almost fixed the 180 again.

Had something interesting today after flashing the ESC's with the latest firmware.

First, while still with the older firmware(blheli14.3), when I plugged in the battery the ESC's started up synced. You could hear the startupsounds all at the same time. But after I flashed to the latest firmware(blheli14.6), the startup was unsynced and the sounds where all garbled. Plus some of the motors started spinning randomly by themselves, and this time it was not a loose plug on the flightcontroller. So I flashed the ESC's back to the firmware version they came with and all is okay now.

Finally after a month of waiting, and replacing the broken ESC, I just did first testflights with the 180. It flies fantastic, not a lot tuning necessary.
Now that I figured out what caused the random motor spin-ups in the beginning, everything is good.
I tried recording the flight, but had forgotten to charge the cameras battery.
Also getting more used to the Taranis. Having fixed the bumps in the throttlestick is really a big improvement. Landing is much easier now.

Great news m8y

muckyman wrote:

Great news m8y

Finally can get some flying done, waited long enough. Ordered that ESC from Europe so I didn't have to wait so long. But they sent it from China anyway. Took about 3 weeks to arrive via the normal mail. Also nice I'm starting to feel a bit more comfortable with all that RC stuff. At the beginning of the year it all looked like it could be too much and difficult to pick up, never even thought I could build my own quad.
 

Here's a video of some easy flying with my 180, and a few rolls to the left.
Should tilt the actioncam more backwards next time... :

Quote :

Should tilt the actioncam more backwards next time... :

Yes,it looks to much groundwards.

Nice to see it flys so well,feels great when put together something from a vast array of parts and it functions correctly ...I bet your very chuffed.

muckyman wrote:

Quote :

Should tilt the actioncam more backwards next time... :

Yes,it looks to much groundwards.

Nice to see it flys so well,feels great when put together something from a vast array of parts and it functions correctly ...I bet your very chuffed.

Very chuffed indeed

Now I'm starting to learn how the quad reacts, it's getting more fun, less crashing and better flying. Because of the OneShot125 and SBUS the 180 is much more responsive then the Eachine, making flips and stuff much easier, though it still takes time to get used to the turnspeed. It can turn ridicilously fast. Also getting a feel for the hangtime, which is necessary for doing tricks and loops.