API Question ShiftCG

[gattispilot]

Do you know where you saw the aerodynamics lift/drag mentioned. I think for now if I can get the aerodynamics then the user can land the craft. Of course there is another shift cg

Thanks

 

[Urwumpe]

Do you know where you saw the aerodynamics lift/drag mentioned. I think for now if I can get the aerodynamics then the user can land the craft. Of course there is another shift cg

Thanks

Would need to look at my home computer, I have saved the interesting MSL documents on my NAS there.

The re-entry guidance algorithm is also not that complicated, there is a nice technical report about it and its performance until parachute deployment.

 

[gattispilot]

Thanks

The re-entry guidance algorithm is also not that complicated, there is a nice technical report about it and its performance until parachute deployment.

For you for maybe not complicated for me YES!!!!:lol:

Any way We may put a beta of her out

 

[Urwumpe]

For you for maybe not complicated for me YES!!!!:lol:

Of course. :lol:

But then, I also have it much simpler because the C++ language and the general software engineering tasks are absolutely no challenge for me anymore and I can dedicate more brain time to such problems... you'll get there as well.

 

[gattispilot]

Looker forward to the document. Been adjusted the meshes/textures

 

[N_Molson]

He is eventually going to drive you into that : [ame="http://en.wikipedia.org/wiki/PID_controller"]http://en.wikipedia.org/wiki/PID_controller[/ame]

Have fun.

 

[gattispilot]

He is eventually going to drive you into that : http://en.wikipedia.org/wiki/PID_controller

Have fun.

I am just looking forward for msl aerodynamics.

 

[Urwumpe]

Here is the reentry guidance scheme:

http://ntrs.nasa.gov/search.jsp?R=20130009144

 

[gattispilot]

Interesting. I guess. So how much the aerodynamics be set for the aoa?

 

[gattispilot]

ok. I have redone the airfoils. matching the orion re-entry. But I get no lift.

void VLiftCoeff(double aoa, double M, double Re, double *cl, double *cm, double *cd)
{
    static const double step = RAD*30.0;
    static const double istep = 1.0 / step;
    static const int nabsc = 13;
    //    Angle of attack                     -180    -150    -120    -90        -60        -30        0        30     60        90        120        150      180
    //    static const double CL[nabsc] = {    0,    -0.12,    -0.1,      0,      0,      0,    0,        0,      0,     0,        0.1,    0.12,    0};
    //    static const double CM[nabsc] = {    0,    0.0002,    0.0004,    0.0004,    0.0003,    0.0002,    0, -0.0002,-0.0003,-0.0004,-0.0004,-0.0002,    0};
    static const double CL[nabsc] = { 0, -0.12, -0.1, 0, 0, 0, 0, 0, 0, 0, 0.1, 0.12, 0 };
    static const double CM[nabsc] = { 0, -0.0002, -0.0004, -0.0004, -0.0003, -0.0002, 0, 0.0002, 0.0003, 0.0004, 0.0004, 0.0002, 0 };
    // lift and moment coefficients from -180 to 180 in 30 degree steps.

    aoa += PI;
    int idx = max(0, min(11, (int)(aoa*istep)));
    double d = aoa*istep - idx;
    *cl = CL[idx] + (CL[idx + 1] - CL[idx])*d;
    *cm = (CM[idx] + (CM[idx + 1] - CM[idx])*d) / 10;
    *cd = 0.25 + oapiGetInducedDrag(*cl, 1.27, 0.3);
}

// 2. horizontal lift component (vertical stabiliser and body)

void HLiftCoeff(double beta, double M, double Re, double *cl, double *cm, double *cd)
{
    static const double step = RAD * 30;
    static const double istep = 1.0 / step;
    static const int nabsc = 13;
    static const double CL[nabsc] = { 0, -0.1, -0.1, 0, 0, 0, 0, 0, 0, 0, 0.1, 0.1, 0 };

    beta += PI;
    int idx = max(0, min(11, (int)(beta*istep)));
    double d = beta*istep - idx;
    *cl = CL[idx] + (CL[idx + 1] - CL[idx])*d;
    *cm = 0.0;
    *cd = 0.25 + oapiGetInducedDrag(*cl, 1.27, 0.3);
}

CreateAirfoil(LIFT_VERTICAL, _V(0, -0.01, -0.1), VLiftCoeff, 5.5, 0, 1.27);
CreateAirfoil(LIFT_HORIZONTAL, _V(0, 0, 0.01), HLiftCoeff, 5.5, 0, 1.27);