Henry you where right, more Q_TILT_MAX and higher Q_TILT_RATE_DN was the solution for a Tri Tilt.
https://drive.google.com/file/d/12JUWlmpcL2fPSIcQbwQPXYepMw-ugIbZ/view?usp=sharing
I have a question about Weathervane.
There are two possibilities to enable it:
Its “AND”. The parma needs to be enabled. Then RC option then overrides.
do you have more data on that build? I am really interested in it
That plane did fly but it was fairly unstable during descent. I wouldn’t recommend a delta wing without vectored thrust, it just never has enough pitch control in hover. I’m building a non vectored flat wing and expect it will be better.
The airframe was a Zeta Phantom FX 61.
Quick question and apologies if this is not the right place. I have a pair of HobbyKing GoDiscover wings (an old foam delta) lying around and thought to convert them to a vectored tailsitter using a Pixracer and some 3D printed stuff for the fuselage. I am now at the first step, which is figuring out what motors to order. The wings (both of them, including servos) are approx 400 grams with a 134cm wingspan.
I am guesstimating a TOW of around 1 kg, though it will depend a lot on choice motors and battery. Based on this, I am also guesstimating a total max thrust of around 1.5 kg or thereabouts but not entirely sure what is a comfortable thrust to weight.
So, the questions, what are (should be) my design considerations? Screaming, high RPM, short props, close to the fuselage? Laid back, more quiet, long props, way out there towards the wing tips? High / low KV? High or low battery cell count?
Personally, if I have things right on my head, I would tend a bit more towards longer, slower props and higher forward flight efficiency at a (reasonable) cost of manoeuvrability. However, I am really at a loss of how this intent would translate in numbers in this case.
Any tips would be most welcome.
use longer props and place them further from the leading edge, use longer tilt mounts…I would put them about 1/3 span (LGTM)…I would tend to go more for 2:1 thrust so hovers closer to 50% (thrust is not linear with throttle % but close enough)
here is an example in that class range C1 Chaser TVBS Conversion Instructions
Not sure if this is the proper way to start a new thread.
I have been testing a dual motor (non-vector) tailsitter for over 1 year, but failed. Main problem
is when both motors are rotating in tailsitter mode , only 1 control surface responds
INTERMITTENLY and randomly when I move the elevator or rudder stick. Sometimes both control surfaces move very briefly. Param attached
Tailsitter param.param (18.0 KB)
I am using CC3D Revolution as FC. Not that my setting for servo 3 and 4 is 77 and 78 (for elevon left and right) in MP. But the setting for some guy and also in Wiki ask to set to 73 and 74 (for throttle left and right). I just wonder how does the latter setting achieve elevon behavior ?
Pls offer any help to solve this 1-year long issue. Thanks
params look okay on a read thru…unfortunately that autopilot has no logging capability…so more help is difficult to give…if you put it in manual mode do the elevons work correctly and if in FBWA try to stabilize the plane?
Hi Henry,
Thanks for your reply and help. After sending you the last email, I continued to do more trial and testing, and found out some of the controls are reversed, either in MP or Tx. Eventually I got it all right in terms of control direction for tailsitter modes and airplane mode (both FBWA and manual).
However, the control surfaces still don’t perform perfectly in that there is one control surface moving later than the other one, some does not move at all in response to stick movement.
I here attach the video …note I am MODE 1 (left stick for elevator and rudder.).
Can you shed some light on what’s gone wrong ?
Thank you.
Frankie
20230831_152404.mp4
what mode is the video showing?
It is in QStabilize mode.
I know this is not related to the DUal motor tailsitter. But my copter tailsitter would not want to decent because it could not achieve home point due to the wind. It tried to move towards home but it simply could not move towards it. how can I make it more aggressive move towards home? Log
Hello dev team, I am new for the tail-sitters.
I am working on a tailsitter since last 6 months, since the beginning I’m facing issues with my Qloiter as its drifting away and does random yaw+roll /pitch+yaw. But controls in Qhover are so good that i can make it stay in any place and can control anywhere.
Even with this I tried transition some times, where the QRTL was so scary that i almost lost 2 times and crashed badly. In QRTL it comes to home radius very well and in VTOL does every maneuver possible.
I request for some advises to correct the issues and are much appreciated.
Hello people, I had to test the Qloiter did fly well in other modes but loiter,
As soon as switched to Qloiter, my tailsitter is drifting and is unstable like anything.
I don’t understand why and how.
Here is the log.
Please i request someone to look into the issue. (@tridge Please!!!)
you will need to grant open access to that log if you want anyone to look at it
I will grant access if asked.
I don’t see anyone requested for it.
Hi guys, Ive been facing an issue with the dual motor vectored tailsitter.
the issue is that post back transitioning the throttle value drops significantly, which causes the system to go unstable
attached is the log to the same flight.
im assuming the drop in throttle causes the system to become unstable in windy conditions, and then causes the failure.
how do i go about solving this throttle drop?
Hi all,
I am struggling to set up my TVBS (Thrust Vectored Belly Sitter).
In my understanding, I have to set the Motortilt-servo trim to forward flight position and in QHover/QStabilze the Motortilt-servo should move in positive and negative pitch angles to control pitch/yaw.
But mine is only moving up to the trim value but not to negative pitch angles (see video):
https://www.swisstransfer.com/d/6c3c4983-3c57-4bbf-bb8b-3f541edcae66
The servo can move from positive to negative and the trim value correspondence to the forward flight position.
I have set Q_TAILSIT_ENABLE,1 / Q_FRAME_CLASS,10 / Q_TAILSIT_MOTMX,0.
My Elevons are moving correctly but since I want vectored thrust they are to small for control in hover.
What am I missing?
btw: the bin-file of the video above : SwissTransfer - Envoi sécurisé et gratuit de gros fichiers
Thanks for the help 
