@devres A good source for example parameters is the SITL_models repo:
Find a model there that is similar to yours, and start with its parameters.
Probably the best example for a non-vectored duo-motor tailsitter is Tridge’s here:
Hello! Great job. Unfortunately, I have no experience with 3D graphics. Could you share the stl file?
Thanks.
Which files do you mean?
My 3D Max Design Programm can export .OBJ Files only. The Slicing Program Cura can read .OBJ and .STL Files.
You can download the actual files here:
I am very grateful to you. Many thanks!
Hi
Long time reader, first time writer.
I have been developing dual-motor vectored tailsitter for 3,5 years now, so I know some basics about this 
I have lot of questions, but I’ll start with the recent one.
When changing from forward flight to hovering (examble fbwa -> Qstabilize), pwm outputs kinda locks to straight flight position and throttle goes to Q_M_THST_HOVER value (e.g. Q_M_THST_HOVER = 0,6 -> throttle output = 1600 ms) for 2 seconds.
After this, motors turn full upwards and throttle goes what is commanded from controller.
This kind of behaviour makes back transition way too fast and rough and strains components unnecessary. Also during this 2 sec time, plane just flies ‘‘straigth’’ and can’t be controlled.
So, what I have been testing, I havent found a way to alter this 2 second behaviour. I red that this was hardcoded to arduplane code. In my opinion, this needs to be adjustable someway.
So the question, can back to hover transition event be adjusted someway?
Specs:
Pixhawk 4, Arduplane 4.0.3, plane TOW 12 kg, max thrust ~24 kg, dual-motor vectored tailsitter
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That is a hard coded 2 seconds time out. However you should not be timing out. The code is expecting the forward flight controller to reach the transition angle it only times out if it cannot get there. This could be because your flying so slow there is little control authority left. Changing Q_TAILSIT_ANGLE moves this angle target, a lower value will mean it has to pitch up less in forward flight before the controller swaps. If you look at the logs you should be able to tell what angle its managing to get to before its timing out you can then set Q_TAILSIT_ANGLE to a little less than this.
EDIT: if you have a very long Q_TRANSITION_MS (larger than 4 seconds) it could just be that 2 seconds is too short
Hi
Made more fligth tests. Maybe fligthspeed is problem, airspeed is over 18 m/s before changing to hovering (ARSPD_FBW_MIN is 17). Maybe Q_TAILSIT_ANGLE 75 deg and Q_TRANSITION_MS 7000 ms are too much, but this way I have got smooth hover -> forwardflight transitions.
But now I stumblet to new problem. In AUTO flight, when changing to hovering, the throttle drops to zero for about 1 - 2 sec after plane makes transition sequence. Even when doing VTOL takeoff and next command is DO_VTOL_TRANSITION (3) keeping plane in hovering.
Maybe this happens because altitude target is set at the beging of transition sequence. Plane gets height 5 - 15 m during transtition and during zero throttle time starts to drop. Scary maneuvers after this.
Maybe Q_WP_SPEED_UP: 700 cm/s or Q_VELZ_MAX: 900 cm/s are too much?
Another thing is about WP commands. Do waypoints have vertical radius like they have horisontal? In automatic hovering WP gets completed even when commanded height is 5 m and plane is in 28 m.
Secondly, is there a command that keeps the plane in one position and let to other commands like setting servo or camera? LOITER_TIME seems to keep plane in place, but DO_ commands happens only after set time and durind plane moves to next WP. Doesn’t copter have delay command in normal WP parameter, is this possible in plane hovering?
Thanks for your efforts, Risto
maybe try to increase q_m_spin_min to keep more airflow over control surfaces
Also I would try to play with Q_PxxxZ parameters to make altitude change detection more sensitive,
Reduce Q_PxxxXY parameters to make position control less sensitive
and q_velz_max to 100
need some help
skywalker x5 tailsitter vecotor motor.
servo1,2 elevon, servo3,4 tilt servo, servo5,6 ESC. micro pixhawk with arduplane plane v4.0.5
problem: X5 power safety button on (solid led) disarm , rc TX power on if flight mode on FBWA two motors start spin under disarm condition, raise TX throttle motor no reaction. swith to other VTOL mode motor stop. don’t understand why motor spin under FBWB mold and disarm.
BRD_PWM_COUNT is only 4…
That can’t be right, can it?
Are you sure you flashed the right version of the firmware? I don’t see “micro pixhawk” in the list of supported controllers.
Thnak you, will check with BRD_PWM_COUNT=6. used MP flash firmware board identify automatically.
Thank again for your help
Hi Jiri, I hvae the same problem here. I recognised the AHRS and EKF are frequently turning red and heading and roll values change though the tailsitter is still on ground and not moving. Have you found a solution?
Thanks
Thomas
I’m trying hard to get the default tailsitter model flying in SITL but without success so far. I’m running ./sim_vehicle.py -v ArduPlane -f plane-tailsitter -w --console --map and after initialisation the hdg keeps turning, roll changes a lot and pitch is -89. AHRS and EKF is mostly red. When I change to qloiter or qhover the pitch changes to 0, roll also moves to 0 but hdg keeps changing. Trying to arm I get the message gyros inconsitent. Turning off the pre arm checks and setting rc 3 to 2000 the current goes to 50A but the tailsitter stays on ground and doesnt move.
I started with default params and also played around with
AHRS_EKF_TYPE 0 and 3
EK2_ENABLE 0 and 1
EK3_ENABLE 0 and 1
but never got it working.
I have no problem taking off and flying the dafault quadplane. I’m using latest master.
Any ideas what I’m doing wrong?
thanks and best
Thomas
The built-in tailsitter simulator (-f plane-tailsitter) is broken.
But simulation in RealFlight (-f flightaxis:) works well.
example:
Hello All !
Am new to this forum,
Need some help am trying my frist VTOL Tailsitter , Using a Matek F405 , have wired everything .
All seems to work ok in Plane mode but the Motors fail to arm in Q or Hover mode,
There is no PWM signal even on the Servo tab of Mission Planner.
Am uploading my param file
Help would be a real Favour
Regards
Dr Nayeem
VTOL.param (22.3 KB)
Finally i was able to arm both in Q mode as well as Plane mode
I could not get the reason though i had to down grade the firmware to get it working
But now am stuck with another issue ,
The servos are continuously active and 'Humming" and get hot i lost the servos as they became unusable. I tried all possible things i could think of but the problem persists.
Please Help Me Out
Regards
Dr Nayeem