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Assembly problems with parallelogram


New member
I have an assembly in mechanism that features a parallelogram. It keeps moving itself in knots, which obviously it can't physically. The mech will follow half a path, then jump into a crossed position at any given time. It is then strangley stuck in a knot which is really hard to get out of!

Is there a floating parallel plane command or something I haven't found?


New member
I assume you're talking about a four-bar linkage right?

Within the Mechanism module, try setting rotation angle limits under Joint Axis Settings. Can you post a picture or provide more description?

Dave Martin

Torgon Industries


New member
Thanks for the suggestion, it's worked perfectly. I've added the new rotation contraints, which makes sense now.

Weird how the answers are always so obvious?!