Nimbus Tricopter VTOL

Pascal,

Thanks for the correction. On the DIY versions, we use 25mm tube clamps from AliExpress.

Although I couldn’t find a close up image of the V2, it sounds like the Foxtech version uses a level platform that needs some washers to offset the motor angle slightly. I can’t imagine that there is much torque to offset that can’t be handled by the vectored yaw so it likely is used to center the tilt rotor offset.

I’ve never noticed any significant offset during a hover.

rear motor

Hi Greg and Pascal, Thankyou, I have attached an image for future reference. Another commercial operator here in Oz has confirmed this on his too.

Am I viewing this correctly? The two washers are tipping the rear motor slightly forward or backward? (not left or right) I can’t tell if we are looking at the forward or rear part of the mount.

Hi Greg, tips the motor to the right, just my poor photography skills

Take care

Steve

washers Nimbus

Hi Greg here is a ‘better’ picture to correct my previous post washers are on the Right tilting Motor to the Left.

Thanks, Steve. I realize now that the washers are used to offset the motor without disturbing the rear landing leg position. Otherwise, why not rotate the whole mount. As you said, it must be used to cancel a slight offset seen in the vectored yaw control.

I will post a file of my Foxtech channel mapping I have highlighted a couple of items I could really use an explanation for. If anyone is able to assist.

Channel Mapping Foxtech Nimbus.docx

Hi Steven,

I’ve also been curious about those settings when I got my Nimbus from Foxtech and asked them about it. After getting some confusing information first, it turned out that servos 3, 11-14 are linked to payload control. Normally, RC buttons SC, LD, RD, SA and SB for supposed for controlling those servos.

In my case, I’ve asked for preparation for a 2-axis gimbal, and got servos 13 (Aux5) and 14 (Aux6) wired to the payload section. The others can be freely used for zooming, remotely powering, etc.

Now, relating to your radio buttons, I cannot find any NIL button no my controller. Where did you find that information?

Hope that clears up a bit…

Hi Pascal,
First NIL means that they have no RC channel assigned to them and/or No function assigned to that channel.
Thankyou-- Did you have Aux3 with wires connected? Did you find out where they went to? I think it could be for my 8.4V camera out- I have no intention of pulling wires out at this point or the flight controller as wires fun everywhere (@GregCovey - you would be horrified).
I have sent it through to Mike @ Foxtech; I really don’t expect to hear back or receive any clarification if I do.
I have turned servo 12 RCIN6 S2 into my Fence toggle at this stage but may just turn fence to auto once I log enough hours learning to fly and start running missions.

Hey Steven,

Aux3 is wired (in my case), however I have no clue where the wire leads. In my case, two slots of the flight controller were not occupied/wired, Out3 and Aux4.

As you state, last thing you would want to do is pulling the connectors out, as cables are shortened to minimum and you’ll have a hard time getting them back correctly.

@GregCovey or anyone that has quick access… what is the diameter of the carbon tube that the tilt servo assembly is mounted to?

Thanks in advance.

Hi rollys,

It should be 12mm.

Hi guys I’m setting up a nimbus like airplane. Basicly all the same.
When applying yaw the right motor goes forward and the left one goes backward, so this ia inverted.
I was told to flip the 2 servo input on the pixhawk or servox 76 to 75 and so. Doesn’t affect the airplane flying in qstabilize mode, how the pixhawk do the correction if i flip the servos. Thank

Hi Dr. Maalouf,

While swapping the SERVOx_FUNCTIONs from 75 to 76 may work, you really need to determine if your R/C channel yaw control is reversed or the yaw compensation is reversed when hovering or both.

From the Wiki: For the 3.8 firmware and above the input side and the output side are completely separated, allowing you to have completely different PWM ranges, reversal and trim on your transmitter input as compared to the servo output.

Using the Wiki section below, verify that your R/C yaw control looks proper when connected to Mission Planner in the Radio Calibration screen. Larger PWM values means yaw right when RC4_REVERSED is 0. Also, verify that your left tilt motor servo is actually connected to the appropriate SERVOx that has the FUNCTION set to 75 (tiltMotorLeft). This will insure that both your transmitter and Pixhawk compensation for yaw should be correct.

Controlling Input Throw, Trim and Reversal

Good luck and welcome to the APM VTOL forum! :grinning:

Thanks @GregCovey for your reply, will work on it tonight and I’ll send you my parameters to make sure everything is ok before test flight.
Actually I’m a arducopter guy since about 10 years now :grin:, i went a way for a while for quad racing and nitro airplanes.
Greetings from Lebanon.

Hi Dr Maalouf and Greg, I am pretty sure that when we apply YAW for tilt rotor Left and Right motor move opposite in order to provide said YAW. In latest plane this is only able to be tested when armed (to prevent accidental arming). I am aware of this because the original Foxtech APJ allowed testing before arming which I though at the time was a good idea- however accidental arming can never end well.

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That’s a good point, Steve. I didn’t say anything because Dr. Maalouf really didn’t say which direction the transmitter stick was yawing. If we assume left yaw then it’s ok.

Its, good to be able to answer or assist occasionally so often I’m the one asking the questions

Take care

Steve

There is an option in master to allow the motors to tilt in response to the yaw stick while disarmed (Q_OPTIONS bit 10):
https://ardupilot.org/plane/docs/common-future-wiki-changes.html#on-quadplane-tips-page

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Thanks guys for your assistance,
The airplane arm and disarm with no problem
When i apply right rudder the pwm goes 1900, so not inverted.
When i apply right rudder the right tilt motor goes forward, that’s the problem.
Thanks
And guys please call me Elie, the Dr thing is because i signed from my gmail account :grin: