The Q_TILT_YAW_ANGLE is for the flight controller so you won’t be able to control it by the sticks. I would recommend setting it to 13, not 30.
Cheers!
Hi Chad:Good morning from sunny Hot Humid Fla,i checked everything again everythings AOK i didn’t have a manual mode so i changed to 1-Manual,2-QStab,3-QHover,4-FBWA,5-Loiter,6-QRTL, In man mode only front 2 motors run NOT the Back,with throttle off i flip switch into Q stab mode all 3 motors jump start then turn off i raise the throttle all 3 motors on, i flip switch to Q-Hover wait then switch into FBWA crap all 3 motors keep running IDK once that back motor starts it will continue to run until your in manual and shut throttle off,any more thoughts i’ll try anything.Thanks B.K
Butch,
Can you post your param file?
B.K Params 9-15-19.param (18.0 KB)
Hi Greg i hope i done this right let me know if i didn’t Thanks hope you find something.B.K
Greg:I also had a question on the wiring diagram for the ubec ,it looks like the motor tilt servo sig wire is getting connected to the power wire of the ail servo wire if so how does the tilt servo get signal?Thanks B.K
Butch,
I don’t see anything in the param file that looked wrong. I would focus on a hover test using QSTABILIZE mode first and then QHOVER and QLOITER once QSTABILIZE seems ok.
Don’t use MANUAL mode as that is for normal planes. The emergency go-to mode on a VTOL is one of the three Qmodes above. My preference is QSTABILIZE since I always have it as the most clockwise position on my Taranis or Horus transmitters.
On the UBEC wiring, don’t let the wire color fool you. The existing stock red wire that runs through the connectors is re-assigned to the tilt servo since it is no longer needed to power the servos. The servos get fed directly from the UBEC now in the wing. This re-assignment has to be accounted for in the main chassis.
Good luck!
I switched the tilt yaw parameter from 30 degrees to 13 degrees. On startup the motors go to a 90+13 degree angle, is this correct?
Or should it just be 90 degrees and I should mechanically adjust the servos?
I don’t know why this is so confusing for me!
Greg: Thanks just being sure about the wiring i don’t like the smell smoke
I don’t know how others are setting this up, but in my case I make it go straight forward for plane modes and 90 degrees up for vtol modes. Once I raise the throttle, the servos start to move in vtol modes. I have my tilt yaw angle set to 20 degrees since 13 did not have enough authority in light winds. now I can have it sideways in 10m/s wind with no prolem.
I agree with Romeo_E on how he set up his Nimbus VTOL. The 13 degrees came from the FoxTech setup and seems to work fine for most of us because it provides a 26 degree swing on each tilt-rotor.
Here is a diagram posted by Rolf and some description by Tridge that may help your orientation.
I admit it is a little confusing, but it should be like this for simplicity:
- set q_tilt_yaw_angle to 13 or whatever works for you
- upon power up (not arming) the servos should be 90 degrees up (the firmware works out the difference between max angle and straight up)
- if motors not straight up adjust max_servo until you get there
- upon arming and throttle up (without props) you can move yaw stick and see the motors tilt
This is how I do it.
Between Romeo and the Pic that Greg posted I was able to get her to work!! I was doing motor testing when I saw that the right motor servo likes to “twitch” all the time, please see the video and tell me what you think:
I’m guessing noise on the line?? Bad servo? Can I ignore this?
Everything is tight so it’s not a loose mechanical anything…it’s 100% coming from the servo itself.
If the Rx antenna is close to the servo wire try to move it and see if it cures the twitch. Otherwise I would not fly with that servo.
It’s an odd twitch on just the right side. Does the same servo also twitch when facing forward?
Can you plug in a servo tester at the servo cable to see if it is the servo or noise on the line? It might save some work if you don’t need to remove the servo. Even a cheap one like this $4 Servo Testor from HK would do the trick. I keep one in my flight box and one on the bench.
If it is noise, then you’ll need to move the servo wire around a bit. I would start from the Pixhawk end.
Good luck!
Hi Greg: while waiting on a few Parts, speed sensor,servo rod quick link,I wired the wings as per description then wired up the pixhawk now thats were i’m having a prob, the wing wires are joined together into a Y cable so do i split them and make cables for the FC cause their is only one esc wire for only one motor? Thanks B.K
@Butch Yeah, I stripped out ALL of the factory wiring and ran my own, this required splitting the tail section open to gain access. I did this because the factory wires are not exactly good quality nor do they carry the ratings to use 2S servos (I replaced all of the e-max servos with 2S servos) amp wise. You will also find that the factory guys are fond of running a single signal wire instead of both a signal and a ground wire. In my experience that is a great way to cut down on expense and a some weight but it’s also a great way to introduce a single point failure when the ONLY ground wire you have attached comes loose. When that happens any connection without its own ground will cease to function or not function correctly depending on how the rest of the wiring system interacts.
Here is what I made up to guide me through the re-wiring process in case you want to give it a go:
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Motor Servo Twitch SOLVED:
Greg was right, it was noise. It is noise being induced into the signal wire of only that servo and its coming from the RFD900x that is about 23 inches from the servo itself to the base of the right side 900Mhz antenna, or another measurement is that the servo wire end (that is plugging into the back of the Pixhawk 2.1) is about 10 inches away from the same base point on the right side antenna.
I can verify this by covering the 1W output 900Mhz antenna with my hand and the pulsing stops (I assume its pulsing because of the heartbeat function?). I can also make it stop by pointing the antenna straight down the fuselage towards the tail and thus the servo wire is getting the shadow of the dipole antenna.
What is weird is that the same is not happening to the other side of the wing! RFD has diversity reception and some form of output so I unscrewed the offending right hand side antenna (right side referenced as if you were sitting in the cockpit of this drone) thinking that the output signal that was causing the noise on the right side servo would stop (and it did stop) and pick up on the left side servo (which it did NOT).
This leads me to the fact that due to the way the autopilot is sitting in the fuselage that the extra 6 inches or so required to reach the other side to be plugged into the servo rails is just enough and positioned just right enough to have this noise induced. I’ve basically turned my servo wire into an antenna.
Not sure how I’m going to handle it, I can:
- Reposition the entire RFD900 (which is not a good option for me)
- Fix the offending antenna into another 90degree angle (which means pointing it at the tail in which case I get an RF shadow due to the carbon fiber tube)
- Attach a ferule to the servo wire (band-aid to the problem)
- Take out the damn autopilot again and redo the cable management until the twitching stops (which may or may not work at all)
- Lower the power output of the RFD (umm. NO.)
- Find some pixie dust and sprinkle it ambley.
Any other ideas??
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Hi Greg:Thank You, Darn and i just ordered a spare set of emax servos when i read previous comments on this thread about servo problems,so what servos do you recommend what gauge wire and and where do you get the 8.4 volts from and how does that affect the Pix FC,AS you can tell i’m not the brightest bulb just a old retired Blue color SPED just trying to run alongside the big boys but dreams need to be pursued and Thanks again for all your help and wisdom i’m here to learn and i’ll try any thing it just takes me longer.B.K
Butch,
I just split the existing Y harness as in the original conversion by Kris. A thicker common ground wire is run for power to the ESCs and BEC which is fine for the servos.
It looks like Chad went the extra mile to replace wires and servos. After replacing my one bad Emax servo in the tail, I have not seen a problem since. You can always take the quick solution and then re-do things in the winter months.
Chad,
Your issue with the higher powered RFD900 is common. I had a similar issue on my APM Antenna Tracker. In my AT setup, I was able to move my antenna positions.
Another option for you would be to use the RFD900 at the base station only. You then use the normal 3DR style telemetry units on your aircraft. I did this on my setups because it is more cost effective and still provides a good 5 or 6 miles of telemetry distance. In essence, you don’t need an RFD900 at both ends unless you plan on flying a 25 mile (46km) range.
I don’t think attaching a ferule to the servo wire is a band-aid. It properly reduces or eliminates the RF field riding on the wire.
Good luck!
Thanks Greg: They Call My Wife and I Early Snow Birds we have already been in Fla for 3 weeks for the Winter so i really don’t have winter months only space constraints living in Good Life RV Resort And a Huge Area to Fly All to Myself. So while i’m reading your suggestions i also read your comments to Chad, i also have 3Dr telem,and was thinking of using my EZUHF or R9M where do You Put any of these on the Plane cause i was going to change over to one of these once or if i get this VTOL Tuned in seeing how the taranis X8R don’t have the Range ? Thank You again.B.K