FPV with gopro and camera mount replicating david's

Gremlo

Member
Hey guys, I built an Anycopter with DT750's and it flys GREAT!

so i got the "Frame" go pro mount wich allows you to use the Video out cable while using an actual go pro mount. Really nice!

My question is, When i angle the camera down like Davids mount does when i'm hovering the angle is okay but when im Flying fast forward then all i see is the ground. not a real fan of that angle.

anyone else having the same issues?
 

Cyberdactyl

Misfit Multirotor Monkey
Oh yes, when it's a static and fixed camera mount you have to compromise. Do you want a slight downward view for slow flight orientation, or a level camera, or even angled up maybe 10 degrees for very fast forward flying?

I prefer my static cam to be angled down about 15-20 degrees.
 

Gremlo

Member
yah it will be great for shooting action video with the down angle, but for flying fast FPV its (Davids accent) Hooorrrible!
 

kah00na

Senior Member
I was looking at this for a while too. I wanted to put my camera on a pitch-only gimbal and connect it to the KK2 board just for this reason. With my first, faster tricopter, it nearly stands upright when I really gun it and I'd still like to be able to see where it is going with FPV. I built a small testing piece and worked with it a little but with more and more movements it seemed to slowly inch backward - pointing more upward. I didn't actually ever put it on my tricopter though. I got the idea from this Reptile frame.
 

Craftydan

Hostage Taker of Quads
Staff member
Moderator
Mentor
kah00na,

Are you using a second control board or is the gimbal using an extra channel off the same board?

For a truly stabalized gimbal, the sensors need to be on the gimbal and as close to the center of rotation(s) as possible. Otheriwse the board is just guessing at how much it needs to jerk the gimbal to cancel the jerk in the airframe, instead of actually measuring it (not saying anything about jerks on the controls, I'm sure you're quite nice to the airframe ;) )

From what you're describing, it sounds like error induced from the control board's guessing accumulating over time. Fine tuning the guessing will help, but if you're not actively controlling it and it's just guessing, yeah, it's gonna drift.
 

kah00na

Senior Member
Are you using a second control board or is the gimbal using an extra channel off the same board?

I'm using a KK2 board and using the pitch-gimbal support channel off of it. I don't want to use the roll because I want to know which direction (left or right) my tricopter is leaning. I can figure out the pitch direction based off which way it is moving. I was also trying to get it work using some extra 9g servos I had laying around. I need to get better at FPV before I invest any real money in something like this.... "start simple".
 

Craftydan

Hostage Taker of Quads
Staff member
Moderator
Mentor
Fair enough.

I haven't gone near as far as you have, but my control theory background was screaming in my ear as I read your symptoms.

Keep up the good work, but you're fighting the physics -- you'll have to live with drift until you've got something to measure/correct it on the gymbal, whether it's a second board, head tracking, or the Mark I Eyeball + tx control (not sure how that could be made to work . . . ).
 

Johan

Senior Member
What about the SSG? http://www.rcgroups.com/forums/showthread.php?t=1793759

You could leave out the roll correction and just use the pitch. Even if you get some drift you should still be able to see...but to be honest, it seemed like there was almost no drift once setup was adjusted.

I stubbled upon this thread as well, it is looking very clever! I searched for the thread number to see if anyone had seen this before, could have guessed :)

In fact I just printed out the PDF and plugged two 9g servo's into CH7 and CH8 of the KK2 and stuff moves (well after setting the roll and pitch gain for the camera gimbal settings on the KK2)

Arghh... yet another thing for the working bench (Guess I should make up my mind first ...)