Tuning MultiWii for aerial video

[sismeiro]

Hi,

I have a MultiWii quadcopter (http://www.multiwii.com/forum/viewtopic.php?f=9&t=1658) and although I am still learning how to fly it, without much tuning I like the way it flies and maneuvers:



My next step would be making some aerial videos but for that I think my Xcopter needs to be more "locked", if you know what I mean.

I already read some instructions about how to tune the PID parameters but I would like if someone can give some tips on how to optimize the configuration for making some aerial movies. Thank you.

Regards,
Luis Sismeiro

[Zenman]

This is a great subject. I just recently built a small fpv rig and have been searching on the forums for information on how to tune multiwii for the best video. I like seeing some examples of what is posible by watching other pilots video footage so that I know what to shoot for. I'm not able to find many examples of fpv flights with a multiwii fc like I can for OpenPilot.
Right now it seems my copter flyes very stable, has great control, but the video is too shaky. I'm in the process of adding some vibration dampening for the FC as I believe there might be too much vibration reaching the board. Also, it seems for the high frequency vibrations lowering P down to 3 and below is helping alot, but at the cost of some control it seems.
I am wondering what what can be done with a low cost MultiWii fc like fhe Flip 1.5 i'm currently using or if I'm better off moing up to a naze32 or even a CC3D.

Perhaps some of you guys would like to share some video footage from your fpv rig, along with some details of your set up and pid's.

Luis, have you have any fpv flight videos you would like to share?

[copterrichie]

Many have turned to using a Gimble Stabilizing system however, I believe it is still better to have a very stable copter first. Because most copters using MWC are unique, there is no standardized procedure for tuning based upon what I have observed, other than lots of trial and error testing.

[sismeiro]

Perhaps some of you guys would like to share some video footage from your fpv rig, along with some details of your set up and pid's.

Luis, have you have any fpv flight videos you would like to share?

Hi,

Finally someone picked my post. I don't do FPV yet, only LOS flying.

Regarding this topic, I have made several tests trying to find the best MW PID configuration in conjunction with RATE and EXPO. I started with the default PIDs and using the instructions in the MW wiki (http://www.multiwii.com/wiki/index.php?title=PID) I increased the P parameter, decreased the I parameter and increased the D. Also I changed the throttle EXPO and the Pitch/Roll EXPO to make it more smooth.

This is the result I got, the landing gear was a recent addiction tested today. Sorry about the jello effect but I removed the vibration dumping system that I had before the gear upgrade.

From outside:


From inside:


My gimbal is on it's way, until them this is the best results I will get.

Edit: trying to make a movie with my gear:


Regards,
Luis Sismeiro

[sismeiro]

Hi,

I have been doing some flights with the purpose of stabilizing my quadcopter while hovering. In my latest tests I reduced the D parameter of the pitch and roll to 5 and it was very stable, eliminated the small twists while hovering. Also I reduced the I parameter a little. If it's not perfect, it's very close to it.

The conclusion is, even if you thought that the changes you made before while testing were the sensible ones, go even further and you may have a good surprise and find the very sweet spot were your multicopter will excel.

Regards,
Luis Sismeiro

[Noctaro]

Hi Luis,
did you set your gyro lpf to 42hz in config.h?
This may help alot against twitching caused by vibrations.
Btw. nice locations to fly at

Keep it up!

Greetz Noc

[copterrichie]

Personally, I have always used this double-sided vibration reduction tape for mounting my FC's, works very good. There is a newer process that uses the same mounting rubber balls used on camera gimbals that I would like to give a try.

This stuff is cheap, so I use it generously.

http://www.hobbyking.com/hobbyking/stor ... thick.html

[sismeiro]

Hi to all,

Regarding the vibrations I don't think I have that many on my Xcopter, changing the LPF wouldn't do any good but I may be wrong. Can anyone post a video of the sensors graphs on MultiWiiGui with the motors running for comparison?



I have this example which was made while flying. There are some interruptions because of the BT link but you can see what kind of vibrations I have.

Regards,
Luis Sismeiro