Jolt on plane dr400

  • Hello everyone



    We paired aerofly with a virtual reality headset and motion platform "MotionSystems PS-6TM-150"


    https://motionsystems.eu/produ…ion-platforms/ps-6tm-150/


    When we pilot cessna for example, the platform perfectly transcribes the movements of the aircraft.


    However when we try the DR400, there is a slight jolt on the platform, while with the cessna, the movements are perfectly smoothed.


    What is this about? Is the Dr400 simulation model wrong? If so, is it possible to modify it? In which files? Which software?


    Is it due to another cause?


    Thank you all for your help


    regards

  • I'm afraid just reporting that you feel a slight jolt doesn't provide much information on your issue... What do you mean and how do you expect it to be related to the flight model?


    Cheers

    Antoine

    Config : i7 6900K - 20MB currently set at 4.00GHz, Cooling Noctua NH-U14S, Motherboard ASUS Rampage V Extreme U3.1, RAM HyperX Savage Black Edition 16GB DDR4 3000 MHz, Graphic Card Gigabyte GeForce GTX 1080 8GB, Power supply Corsair RM Series 850W, Windows 10 64 bit.

  • I suspect its your platform tuning. I use a platform and the C172 is a much more gentle & stable aircraft than the DR400. I get stronger movements with the DR400 and you need to tune your platform accordingly. You're probably mapping acceleration forces to movements rather than absolute angles and these will vary a lot. How do you find it with the Bucker ?

  • Hello, we've just tried the Bucker and it works perfectly with motion platform. We tried also other plane and the only plane that does not work well with the platform is the DR400... Another ideas ?

    Thank you.

    Very odd - the SDK which your platform connects through is no doubt the same as mine although the config for mine is SImTools. The SDK simply provides the physics you experience on screen. My platform is fine with the DR400, just a bit more lively than the C172.


    This one is beyond me - can you experiment with your config? Do you map movements to absolute angles or acceleration forces?

  • And do you feel a vibration or just the occasional glitch?

    Could you maybe find an outside view and see if the "jolt" coincides with a sudden movement of a part like the elevator or landing gear? If you see a part moving just as you feel the jolt then it is an instability in the joints and we should be able to fix that.

  • Hello,

    There is no problem with the control surfaces nor gear.

    It's not realy a vibration with a specific frequency, but more jolts.

    It's difficult to explain...

    i try: ;)

    tac.......... tac...tac.tac..........tac........tac.........................................................tac..tac.........tac............


    It looks like if some parameters to send to telemetry for the motion system are probably set to 0 briefly? acceleration? speed? angles? i don't know... it's only an hypothesis...






    I found a problem on the acceleration parameters (needed for the motion system).



    I compared CESSNA and DR400, and the result is on the file below.



    We can see the jolst only on the DR400 aircraft.



    CESSNA is OK.


    AeroflyCurves_Jolts.pdf




    Could someone help me?

    This is a realy blocking problem for my study.

    I try to evaluate DR-400 flight in real flight Vs virtual flight, and i chose AeroFly for the virtual test...

  • It looks like you don't save the values for all the parameters long enough until the next message arrives. If you keep the old value for x seconds and replace it when a new value comes it (and don't delete it if no value was received) the jolts should go away.

    Or are you really receiving exactly what is plotted on the right side?

  • Yes but you should store the values for some time until they either get updated or can be called invalid after one second or so. We don't always send all the messages and eventually we want to get to a point where we only send values when a state changes. E.g. only send a message when a switch is moved to a new position or when a text updates. Any receiving side should buffer the values and not directly depend on the arrival of a message.