how to specify distance between components and/or rigid groups of components?

[jgordis]

I'm pretty sure this is addressed somewhere, but I haven't been able to find it. 

How do I establish a specific distance between two components, or between two rigid groups of components?  I think it involves joints, but I see how to specify a distance between joints on different components.

Thank you in advance.

[g-andresen]

Hi,

create a rigid joint between the groups and specify the distance at selected points.

günther