Hello everyone:
Taking my last stab at VTOL with the Finwing VTBIRD. So far, so good, although the maiden flight didn’t get very far.
Build includes:
-VTBIRD tilt servo kit
-front motors Sunnysky X4108S 480KV turning 15x5.5 T-motor style props
-rear motors Sunnysky V4006 380KV same props
-Lumenier BLHeli32 36A ESCs all around
-Holybro Durandal with latest Arduplane flashed
Printed the landing gear struts with a 25mm extension to raise the ground clearance for a belly mounted gimbal. Center of Gravity is looking good at a couple of millimeters forward(calculated with tilt motors forward)and the gross is 4150gms with a 6600mA 6S battery - I don’t have a need to fly more than 30min or so.
I raised the rear motors up 25mm because of the prop tip clearance at the tailcone. The fronts are within 12mm of the nose when tilted down, so I might raise them a little, but will go with what I’ve got initially.
The wiring has been straightforward. I’m considering a rudder servo, though it doesn’t appear to be recommended or necessary. My thoughts on it are some out of trim situation where a bit of rudder could be helpful. Or maybe someone can answer the question, are these things flyable with a thrust motor out? Maybe, maybe not, but certainly not without a rudder input. I also plan to use RUD trim as the channel source to not over do it.
The initial hover was done in QHover. Good control response in both Pitch and Roll. Yaw was hunting around with the nose swinging back and forth maybe 15-20deg to either side. Q functions are setup to enable yaw assist, so don’t know if that’s a factor yet. I have also raised the GPS puck up to hopefully reduce any mag interference.
When I attempted a transition, the yaw swing stopped, probably from the vertical fins becoming effective. I didn’t know how fast the speed increased to before the frame rolled right and spiralled down. Going back to QHover saved it. Video on the ground recorded an airspeed increase, then decrease and about that time, the frame rolled.
Any thoughts and tips are appreciated.
https://drive.google.com/drive/folders/1hvtkf33pxx1xHKNN18urAav4PdZ2tUpN?usp=sharing
For the data log and param file
Ron