Building RealFlight8 Models

Ah, probably not actually. How can I check the fps?

Bill, any luck finding a solution?

Hi Peter,
So I didn’t find a solution to the bad terrain data issue however @tridge helped me determine that it was an issue with AC 3.5.5. When I switched to AC3.6 I had no issue using the sim with realflight cennected to Cygwin. I did end up realoading Cygwin and that fixed the issues I was having with it running SITL. So for me that seems to be the best platform to run SITL when interfaces with realflight. I am seeing 260-280 fps. I need to follow up with Tridge to see if there might be an easy fix to this bad terrain data issue in AC3.5.5. I want use it for sims at work since that is what is loaded on our aircraft.
Regards,
Bill

Thanks Bill. Just so I’m clear, you’re running ardupilot in a windows environment under Cygwin?
Has anyone had success with running a Realflight in a Windows VM on an Ubuntu host running ardupilot?

Yes. windows 10.

I know of one other user that has tried that set up and had the same issue that I had with not having enough frame rate for a good simulation.

Does anybody run into the peculiar case where the FPS avg is good (~200) when Realflight window is active and immediately drops dead (No data) when Realflight is in the background? This behavior is very puzzling and I am not sure what is wrong.

Check your physics settings; there’s an option to pause when in background:

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That was indeed the cause. Thanks!

Hi all,

I have been able to get a copy of my FT Bronco TVBS up and running in realflight.

https://drive.google.com/open?id=17ZE85aQV1TUw1uq4aDS20j2ThS9BD-fI

It flys OK on the parameters of the real one, however it will have huge dips in the frame rate down from 300 or so to 20 causing crashes, after 10 or 15 seconds it will go back to 300. Not sure why this is as I can run the models of github no problem. Possibly there is some error in the model or the parameters? It is based on the CUAV tailsitter from github and uses its graphics. I have uploaded .rfvehicle file to the above gdrive. I’m not sure how to export the .RFX file type?

Also I am struggling to compile my own SITL and get it to run with realflight like the .exe does from in mission planner, I have compiled using cygwin make sitl -j4 it seems to run ok from sim_vehicle .py sim_vehicle -f flightaxis:192.168.x.x but not connect to realflight.

Thanks

In RF8, use Simulation/Export/Aircraft variant to export an RFX file.
I don’t have any idea what would cause the frame rate to vary for a particular model. But I also never see 300fps, more like 200fps with a photofield and 150 with full graphics.

Ah, duno how i missed that.

I have uploaded RFX files to the drive link above. I have found cygwin builds a SITL arduplane.exe but have been unable to get it to run. Any pointers on connecting local windows SITL to realflight?

I run SITL under WSL/Ubuntu 18.04 with a command like this:

04:02:36 {quadTSnew2} ~/linux_git/kd0aij/ardupilot/ArduPlane/Dart$ ../../Tools/autotest/sim_vehicle.py -j4 -f flightaxis:192.168.0.100 --console --map

Thanks, I have this working now,

i used this command with cygwin, to connect without launching mavproxy and without rebuilding. I can then connect mission planner via TCP. I guess it was the -j4 i was missing.
…/Tools/autotest/sim_vehicle.py -j4 -f flightaxis:192.168.1.2 --no-mavproxy -N

Still getting frame rate drops I guess although I no longer get the nice readout as before, must be something to do with the model. Also with this method and the mission planner simulation tab, it takes several trys of opening and closing RF8 and restarting the SITL to get the rc controls to passthrough, everything else seems to work first go.

Thanks

I have just had a chance to have another go at SITL, not getting any frame rate drops now for some reason. The only thing i can think is that I still have all the graphics on full, this drops the frame rate down to 230. So possibly the frame rate drops was just due to having too high a frame rate. I guess 300+ fps is just too much for the SITL to keep up with.

Hi all, have been using realflight to mess with the tailsittter code and I must say it works very nicely. I have been playing with the physics of my realflight FT bronco model to try and get it to be more realistic. I am having a couple of issues.

Firstly the realflight landing gear seems to do nothing, is this because I don’t have proper visual frames set up for it? This is annoying as the rounded fuselage in the CUAV TVBS graphics I am using causes the aircraft to drop a wing to one side or the other when on the ground.

I have selected the right size motors and props and the aircraft hovers at the same throttle percentage as the real one. The realfight model however reaches about 50m/s at full throttle where as the real one only gets to 25-30m/s. I need more drag. I have tried increasing fuselage frontal drag percentage to 1000%, this has no effect. Only way i could get it to slow down was increasing the wing parasitic drag to 200% this is the maximum value and this only slows the aircraft by 3 or 4 m/s. Any ideas?

Quite frustrating how linked the physics is the the visuals. I don’t really need it to look right, just fly right, although it is useful to see the control surfaces moving.

Hey!
Can one import CAD models into RealFlight8 and simulate?
Just curious!

yes, unfortunately RF8 uses the visual for ground interactions.

the physics should only be linked to visuals for ground interaction, I haven’t noticed a linkage for flight.
Cheers, Tridge

Thanks Tridge,

I did get it working quite well in the end, still not enough drag though

hi everyone,
KnifeEdge have now released a beta which supports up to 12 actuators for the FlightAxis protocol, which means we can build aircraft with up to 12 channels. This really helps with more complex aircraft.
See the announcement here:
http://www.knifeedge.com/forums/showthread.php?t=33513
I’ve pushed a change into master to take advantage of the extra channels. I’ve also tested to ensure that sending 12 channels doesn’t break anything with the older version of realflight.
Cheers, Tridge

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12? Its better than 8, but I already have a design I’m working on that needs 12 for the copter, 1 for mode changes, 1 for retracts, 3 for the gimbal, 1 for a sprayer channel, 1 for arm/disarm, and probably more… why not just make it 24 or more and be done with it?