Linear-Linear coupler mate

not necessarily

Bob

Linear / Linear is a 2dof joint. One rotational dof and one tranlational dof.

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Can you suggest some mechanisms which fit this scenario?

A Hinge

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It seems to me that a door hinge has a concentric pin and a concident pair of surfaces. I see one rotational freedom and zero translational freedom.

How is my perception incorrect?

True, but some hinges do not contrain that linear dof and some do. If you think about it, in most hinge applications all but one of the hinges do not constrain that axial dof simply due to tolerances.

At this point of pickiness it is best to get out the documentation and see just what the software really is doing with that constrain or build a test case and see what it does. Takes but a minute.

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Of course; a single hinge is not much use to anyone.

The vagueness of the 2008 Help was my reason for asking here so it looks like a test case to convince myself.

Sorry I can't be more help. If you can paste the help here maybe I can see something you can't. It's been a while since I used Motion.

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This is the 2008 help text for Linear/Linear Coupler, in full:-

Linear/Linear Coupler Mate A Linear/Linear Coupler mate establishes a relationship between the translation of one component and the translation of another component.

translation of one component and the translation of another component.

Then it is a hinge because it constrains two translational and two rotational dof and leaves the other two free, one linear and one rotational. It is like a pipe inside a close fitting pipe.

Hmmm, I wonder what a hinge looks like in four dimensions?

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