@eagerStudent 

Update:

I have found a convenient solution to all of this. For whom it may concerns;

--> The 'rhs' command can be used to just take the right hand side of an equation, which is just what was needed here.

@tomleslie 

Forgive me for the delayed response.

As you can see in the file, the trajectories of the coordinates are the solutions of a differential equation, which (necessarely) was solved with dsolve using the 'numeric' option. As far as i understood this, the output of dsolve is in this case not a specified function but just a list of points, representing the coordinates at a given time. Thus, i am not sure that spacecurve will work here.

My intention was to select some of the values dsolve delivers, and put them in a large list which can be plotted by pointplot3D. As you can see in the file (check for the set S at the bottom), i am almost done, i just need to transform it from a set of equations to specific values.

Planeten.mw