# Designing a Parallel Robot by Autocad

These days I'm designing a 5-DOF parallel manipulator with Autocad. Though I know that some people might say that Autocad is not a proper software for robot designing but I only have access to this software at the moment. So here is my question (and I thank you in advance for your help) :

$\textbf{Parametric constraints:}$ Unfortunately I do not know how to put geometrical constraints on my parallel manipulator though I have searched a lot on net and watched some videos about it on youtube. By geometrical constraint I mean putting some restrictions on for example two 3d objects that they can make some restricted moves with respect to each other. For example I have a spherical joint in my robot which I want it to perform some rotations without actually leaving its socket (as depicted in the following basic picture).