Hello all,

I have been working for some time with the multibody library and its animations and this works great. Thanks for all the time people have put in here. I can now simulate exoskeletons and have them moving, showing everyone what is going on.

Of course, with the animations working, I would make it even more clear. For this I would like to change values of the visualization objects dynamically. In the documentation it is written that this is possible, when 'appropriate expressions in the input fields' are given. I cannot get this to work, and hope I do something stupid so that it is easily corrected.

The minimal example below should give an arrow changing from red to green. However, the arrow is always red. In the results I do see that the values of the fa.color change as specified. I hope somebody can give a pointer to the correct solution?

Thanks in advance
Bas

-------------------------------------------------------------------------------------------------
model tst
  inner ModelicaServices.Modelica3D.Controller m3d_control;
  inner Modelica.Mechanics.MultiBody.World world;
  Integer clr[3];
  Modelica.Mechanics.MultiBody.Visualizers.FixedArrow fa(color = clr);
equation
  connect(world.frame_b, fa.frame_a);
  clr = if time < 0.5 then {250, 0, 0} else {0, 250, 0};
end tst;