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> Usage of "outer" and "inner" mechanism in OM, Is the inner and outer feature already completely implemented?
shui
post Feb 26 2009, 11:59 PM
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Hi All!

i plan to use that in my models and few simple examples are fine.
Then i tried this:

model AircraftOM
import ModelicaAdditions.MultiBody;
MultiBody.Joints.FreeMotion freemotion;
MultiBody.Parts.Body acstructure(m = 1, I11 = 0.05, I22 = 0.1, I33 = 0.05);
outer MultiBody.Parts.InertialSystem world;
equation
connect(world.frame_b,freemotion.frame_a);
connect(acstructure.frame_a,freemotion.frame_b);
end AircraftOM;

model Mission1OM
import ModelicaAdditions.MultiBody;
inner MultiBody.Parts.InertialSystem world;
AircraftOM aircraft1;
end Mission1OM;


Then, simulate(Mission1OM) leads to:
Too many equations, overdetermined system. The model has 84 variables and 90 equations

I think that should work. Removing "outer" and "inner MultiBody.InertialSystem" will make it work. The implementation of InertialSystem looks pretty simple as well and i dont know, what could be wrong there.

I know using inner and outer is not really necessary in this case because there wont be interactions between the aircrafts. But i plan to use it to for simulation of wind or wireless communications.

Cheers,
Jrg

P.S.
in order to get it run you need to change in MultiBody.Joints.FreeMotion (watch earlier posts)

when switch_state then
S_fix[1,1] = pre(S_rel[1,1]);
S_fix[1,2] = pre(S_rel[1,2]);
S_fix[1,3] = pre(S_rel[1,3]);
S_fix[2,1] = pre(S_rel[2,1]);
S_fix[2,2] = pre(S_rel[2,2]);
S_fix[2,3] = pre(S_rel[2,3]);
S_fix[3,1] = pre(S_rel[3,1]);
S_fix[3,2] = pre(S_rel[3,2]);
S_fix[3,3] = pre(S_rel[3,3]);
//S_fix = pre(S_rel); //ORIGINAL CODE
//reinit(phi,zeros(3));
reinit(phi[1],0);
reinit(phi[2],0);
reinit(phi[3],0);
end when;
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