I finally had time to assemble my version of the VTOL Bronco. It's a carbon copy of the FT VTOL Bronco, except my VTOL tilt is 3D-printed and based around common T-rex 450 parts. I'm running OpenAero2 VTOL with CCPM 6 channel Rx. All stock FT hardware otherwise.
I drew up the tilt in Solidworks. It is pinned using barbecue skewers just to keep a little heritage in the build.
Ball bearings used for the tilt are from a T-rex 450 spindle. I used the T-rex 450 spindle for the tilt shaft to help keep the parts cheap and easy to find.
I then 3D-printed the pieces on an Ultimaker2 3D printer and installed the servo, bearings and motor.
I'll submit my OpenAero2 VTOL settings in the next couple of days after I get them dialed in, but here are a few things I've noted so far.
Mechanical geometry has to be really closely matched to your servo pwm at 1.9ms-1.1ms. This is because I'm doubling up my gear channel for the profile trigger as well as one of the tilts. The profile channel is set to 'gear' and when I trimmed the travel initially (long on the horn), I couldn't get full full P1.0 and P2.0. I changed the mechanics to more properly align the pwm out and now I'm killing two birds with one stone and don't have to use a y-cable. I like this setup because I really wanted to put the servos on separate channels as well as opposite sides of the respective booms (for symmetry). I'm also running each aileron on separate channels so that I can run a flap mix in the transition. I'm not liking how much servo bind there is with flaps down so we will see if I use it. I really need to redo my hinges for less bind.
Maiden went ok. Transition was fairly uneventful but needs some nose down offset. The big adjustment needed is tuning the low pass filters. The hover work at the end really demonstrates the system lag effecting the phase/gain margin and going slightly unstable.
Fly Fast Fly Safe
-Beall
0 comments