Nimbus Tricopter VTOL

Hi Graham,

I agree. I just have the added confusion that the airspeed logs graph to crap while the GPS ground speed seems fine. The cure for me is to disable ARSPD_USE. The Nimbus transitions and forward flying are then superb. I’m using stable Plane v3.9.8 on a Pixhawk 2.4.8 (Pixhawk 1) pulled in from Mission Planner.

Is your setup using an analog AS sensor? Pixhawk 1? Is there any other commonality between our setups that might suggest an area to look? Doesn’t the code have a transition time-out on reaching ARSPD_FBW_MIN or revert to GPS speed if the airspeed data is garbage?

I’ll connect another AS sensor this afternoon and look for differences.

Cheers!

The second analog AS sensor behaved the same when blowing into the pitot tube. You can see the Airspeed gauge below behave properly. This was true on both setups. Perhaps if a bug exists, a workaround may be to install a digital AS sensor…for now.

After using a multi-meter, I figured out that the connector between the nose and body was not fully mating. There was no artwork or alignment issue…it was simply a depth problem. I fixed my nose connector problem by replacing the three stock screws in the nose board with slightly longer ones and added some spacers in the back to move the board outward. The spacers were held in place with tiny pieces of paper. Now, my AS sensor and gimbal power/control is back to being cable-free.


Greg, Thank you
Graham, These guys are magicians
My problem - hopefully you experts can get it from the log
I took off in QLOITER then change to CRUISE and after a circuit changed to AUTO
The plane pitched up, climb for a few metres , stopped and transitioned to VTOL ( hanging in the air)
I changed to QLOITER and tried to bring the plane back
All went fine but i had no rudder control.
My questions: Why did it not fly the mission and secondly why did the rudder died on me?

Can you post your mission file?

2019-07-10 09-49-23.log0wp.txt (668 Bytes)

Hope this worked

It comes out a bit odd when I open it in MP but I can see it. I think you need to take out the Take-off command from the mission as the plane will try initiate a take-off by going back to hover mode. If flying already then just put a waypoint in as your first mission item.

Not sure about the rudder, is this in 'copter mode? Because the rudder doesn’t work anyway on my Nimbus in plane mode.

Graham,

Did you mean to say the rudder doesn’t work in copter mode? Or is this in plane mode in an autonomous mission?

Cheers!

Rudder surfaces don’t move in plane mode, yaw in copter mode works fine.

Thanks - will change my flight planning procedure and try again
The rudder movement might be that it went from CRUISE to VTOL
without a command (or a none standard command) and switching to QLOITER
over another CRUISE command ( very quickly) did not register properly.

Will check and report back in a week or so.

Hello guys, we just tested the Nimbus V1 with 12000mah 6s, flew 40mins with still nominal values on each cell. AUW was 5kg`

Hi Michael,

Which 6s 12AH pack was that? The Multistar 12C one?

Cheers!

Hello Greg, We use ACRA 30c.

BTW our V2 arrived. Hinges was improve on the tail, Servos were much smoother. Air speed sensor has only 1 hose. Tilt arms improve.

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Very nice! It’s good to see hinges on the control surfaces.

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Guys, We wanted to set the AMP draw on the MP with our NIMBUS, if you guys already have a baseline can you help me out on this.

Michael,

I’m not sure what amp draw you are setting. My setup is very close to a V2 so here is a graph from my recent flight using a light camera payload up front (no mapping camera underneath).

During the “Hover” period, the plane was ascending. For FBWA, the ground speed was 20m/s.

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Greg i was refering to the AMP use during flight. on the HUD bottom left side you will find the battery volt and the ampere consume during flight.

Ok, I see now. On my setup, which is not an official V2, I am using a calibrated Mauch Power Module and that information comes with it to be entered into the BATT_AMP_PERVLT parameter via Mission Planner. In my case, BATT_AMP_PERVLT is set to 64.73156, BATT_VOLT_MULT is 10.00387, and BATT_CAPACITY to 10000.

The only V2 model I have params for is Gordon’s and it reads BATT_AMP_PERVLT is 48…which may just be a default setting.

Thanks for this @GregCovey

Update:

After more than 50 flights we had a mishap during our take off yesterday. Every works fine on the ground.

During take off at QLOITER the RC pilot looses control of the aircraft at 30mtrs. He said that there was no pitch and roll inputs.

Making the aircraft drifts by itself. Can you guys help me analysis the logs.

Oh, that sucks! Sure post a log. What happened to the Nimbus?