OR, increased my fins by 50% and got over 50% higher simulation.

Discussion in 'Rocketry Electronics and Software' started by scadaman29325, Dec 30, 2019.

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  1. Dec 30, 2019 #1

    scadaman29325

    scadaman29325

    scadaman29325

    Catching up and tripping all over myself.

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    The stability was less than 1 caliber and wanted that a little better. Also I was disappointed in the apogee at 359m.

    So I increased the fin widths by 50%, no other changes. And I got 814m!

    Anybody got $0.02 for this?

    Thanks.
     
  2. Dec 30, 2019 #2

    Reinhard

    Reinhard

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    Look at the different plots that OR has to offer, in particular "Angle of attack and orientation vs. time". The plot for vertical orientation should stay close to 90┬░until apogee. The plot for angle of attack should drop to close to zero right after launch and also stay there until right before apogee. If this isn't the case, OR is simulating an unstable rocket skywriting.

    Reinhard
     
  3. Dec 30, 2019 #3

    Voyager1

    Voyager1

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    Yes, I would say that your first simulation went unstable after launch because of the <1.0 cal. Increasing the fin area stabilised it. Also, check your launch velocity and rod length.
     
  4. Dec 30, 2019 #4

    neil_w

    neil_w

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    As always, posting the ORK file and/or plots and relevant screenshots will get you more definitive answers.
     
    Andrew_ASC likes this.
  5. Jan 1, 2020 #5

    Andrew_ASC

    Andrew_ASC

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    OR is 6DOF capable check the excel printouts it can export excel data of like forty plus variables. Within that lies all your pitch and roll data for the stability stuff. At very tiny intervals. You can the compare those between flights and learn the unstable rocket likely crashes.
     

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