Revo with Bluetooth
« on: July 13, 2018, 09:02:11 am »
Hi all!

Can someone point me out a tutorial on using revo as combridge to set the BT device up?

 There are alot using FTDI..
and I dont have one FDTI, nor do I want to install FTDI drivers.

ComBridge I want to use! ;)

Thanks
Cheers,
Rui





Re: Revo with Bluetooth
« Reply #1 on: July 13, 2018, 10:59:04 am »
If I understand it correctly one has to:

1) have the Revo communicating with GCS.
2) Change the hardware settings to VPC and ComBridge. (on the Hardware tab)
3) Save and Unplug Revo. (Force reboot)
4) Connect the BT and Power (batt + bec) to Revo and plug it back. (boot)
5) Open a Putty (or equivelent) session to the com port.

What I don't know is:
Am I supposed to leave the GCS running or not?
I couldn't find the Baud rate settings... It's not on the Hardware tab.
Do we set the baud rate to be the same as expected on the BT device?

Rui



Re: Revo with Bluetooth
« Reply #2 on: July 13, 2018, 01:27:23 pm »
Why not use Oplink instead?  ???

Re: Revo with Bluetooth
« Reply #3 on: July 14, 2018, 06:27:05 am »
Because I have an BT among my stuff already.

Re: Revo with Bluetooth
« Reply #4 on: July 15, 2018, 09:50:37 am »
It's working.

Some un install device (on windows) a couple of times...
And keep the USB and Main Port as Telemetry the whole time!

Next step, try and tune the stabilized flying modes.

Cheers,
Rui

Re: Revo with Bluetooth
« Reply #5 on: July 15, 2018, 05:10:34 pm »
If you can hover without crashing and it has a "Revo class" FC, then you can use AutoTune flight mode.
https://librepilot.atlassian.net/wiki/spaces/LPDOC/pages/25657377/AutoTune

Re: Revo with Bluetooth
« Reply #6 on: July 26, 2018, 08:44:51 am »
Hi,

I managed to stay in one piece but... it was really hard.
Rate mode was almost ok. With some minor sudden direction changes..
Attitude, was really terrible. Once, just after switching to Att came nose down.. lucky me i was high enough to change it back to manual (or rate..) and regain control over it. When trying to fly straight (att), it would drift (not keeping its heading) and shake a bit too much. Att could not keep the height too...
I think, even the manual mode was weird. maybe the CG was off too... I felt it was a bit nose heavy sometimes.


I was wondering if this is 1) normal, 2) poor settings 3) poor hardware placement on the plane.
Next week I will give it another try. Will try to make a onboard video to have your comments.

Cheers,
Rui

PS. Its much more relaxing to fly manual (no fc) for now.

Re: Revo with Bluetooth
« Reply #7 on: July 26, 2018, 08:46:10 am »
Just noticed, this is a bit off topic.
I probably should start another topic, like "setting up Revo" or so..

jdl

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Re: Revo with Bluetooth
« Reply #8 on: July 26, 2018, 10:22:47 am »
Hi,
I guess you are referring to Revo on a fixed wing, not multirotor?! Don't know if Autotune is applicable here. Also, it is desireable the plane to be trimmed fine for manual flight (correct CG is really important!). Small imperfections in control surfaces trims will be handled by FC in stabilized modes.

There should be something wrong with your PIDs, did you changed default values? I have built two planes so far with Revo FC, Wing Z84 and MiniTalon and maidened them directly in Attitude with default PIDs, both successfully. Further tuned PIDs in-flight through TxPID module. But the defaults were fine and planes were easily controllable.

Attitude mode doesn't keep height automatically, neither for multirotors, nor for planes. It just levels the UAV. If you see drifts in Attitude, you may have the FC not perfectly aligned when mounted in the fuselage. Play with AttitudeSettings / BoardRotation to cure the undesired drift.

Violent vibrations can disturb gyros and accelerometers, do you have a lot of vibrations with motor running?

Here is short clip of MiniTalon - takeoff in Attitude mode with 20% evelator, some flight and landing in Rate.



And its maiden in Attitide with default PIDs. Bad roll to the right is caused by 100% throttle leading to massive torque roll ;)


Re: Revo with Bluetooth
« Reply #9 on: July 26, 2018, 12:27:19 pm »
"There should be something wrong with your PIDs, did you changed default values? "
I did. i was following a youtub video on how to set the PID up, and.. maybe that was it.
Guess i should also try the "Further tuned PIDs in-flight through TxPID module". Have to look into it.

"Attitude mode doesn't keep height automatically, neither for multirotors, nor for planes. It just levels the UAV"
I thought it did. Has a barometer...
if not to keep the height, what is the baro for?
As to level the UAV. I dont really know whats the level for my uav. I guess it gets leveled when it's flying keeping the same height...

I do have vibrations. If they are little or too much... that I dont know.
I had the REVO glued to the uav (scotch tape). so i supposed it gets all the vibrations, still I ve flown in diferent engine speeds and I didnt notice any changes.

next week I will try to make some nice shots and videos. maybe from there you can point out what i am doing wrong.
thanks cheers!
Rui

jdl

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Re: Revo with Bluetooth
« Reply #10 on: July 26, 2018, 12:45:52 pm »
Barometer is useful when RevoFC is set to use INS13, not Complementary. In autonomous modes like PositionHold, ReturnToBase, PathPlanner, etc. the FC can maintain height and/or course automatically using all sensors, incl. baro.

FC does see its own attitude and attempts to maintain it. If the UAV goes down in attitude mode and cruise throttle, you can fool the FC that it is tilted (pitched) slightly down (few degrees negative on AttitudeSettings / BoardRotation.Pitch). Thus, when trying to level itself, the FC will point the nose of the plane slightly up ;)
For example, I've set BoardRotation.Pitch = -2 for Z-84.

What is your plane? I can post here the current .uav files for my Z84 and MiniTalon to use settings there as start point or for comparison.

Re: Revo with Bluetooth
« Reply #11 on: July 26, 2018, 04:41:38 pm »
thats a nice tip! thanks, i will use it next time i try!

I am trying to have a bixler2 going on a waypoint missing.

first, flying straight. :)

Re: Revo with Bluetooth
« Reply #12 on: July 26, 2018, 05:54:37 pm »
So is this fixed wing?

Vibrations can cause this kind of problem.  Bad vibration makes the sensors go crazy.  Balance the prop(s).  Is the motor shaft bent?  That must be fixed.

Re: Revo with Bluetooth
« Reply #13 on: July 27, 2018, 05:51:57 am »
hey!

yes its a fixed wing. Bixler.

it's a push plane that never ever has crashed. i dont think the shaft is bent. the propeller... well ive never balanced it. i can see some vibration when i place a small cam on it.
here:

next week i will give it another try with the revo fc.
following your tips.

cheers,



jdl

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Re: Revo with Bluetooth
« Reply #14 on: July 27, 2018, 03:46:41 pm »
Hi,

This seems to me as a LOT of vibrations... Cannot judge, however, if they are enough to fool the sensors, maybe not. I've never flown a model vibrating so much. I like flying FPV and vibrations spoil the feeling (CMOS FPV Cams) and HD video so I always try to avoid them ;)

I'd carefully balance the motor first using some vibration meter app (w/o prop installed), then the prop itself. Then, to be as perfect as possible, I'd find the best position of the mounted prop against motor bell (with minimal vibrations). And even more, I'd try if sticking tiny pieces of blenderm or other suitable tape on the prop, usually close to the shaft, would further decrease the remaining vibrations.

Of course, this makes sense if one flies long time with one and same prop. If there is a significant chance to brake it after some flights (like with racing quads), I personally don't bother balancing props, unless they are exceptionally badly balanced out-of-box  :)