3 Replies Latest reply on Feb 27, 2017 1:16 PM by Ryan Dark

    Difference between Fixed Hinge and Pin

    Sean Erickson

      Hello community,

       

      My first post on here, I'm looking for clarification on the description of the Fixed Hinge option in Simulation. Does the Fixed Hinge option mean that the hinge axis is fixed to the global coordinates and therefore cannot move at all? I'm working on a four-bar linkage system so there are a few moving hinge points in my system. Would the Fixed Hinge option prevent any of the hinge axes from translating and therefore be the incorrect way to model my connections? Is the Pin option (along with adding No Penetration) the way I should approach my model?

        • Re: Difference between Fixed Hinge and Pin
          Sean Erickson

          Anyone? I'm sure the answer is simple, I just wanted to reaffirm that what I am assuming is correct. Thanks a bunch.

          • Re: Difference between Fixed Hinge and Pin
            Siavash Khajehhasani

            Fixed hinge is a correct approach for your simulation purpose. On another note, using pin connectors also gives you more options for specifying axial and rotational stiffness as well as defining mass of the pin and including it into the simulation.

            Hope it helps.

            • Re: Difference between Fixed Hinge and Pin
              Ryan Dark

              Hi Sean,

              You are correct in this.  The Fixed Hinge stops X/Y/Z translations in the global coordinate system while allowing it to continue to freely rotate.  A pin is a similar idea but it locks two cylindrical faces together so they must translate.  They also can still rotate around the axis but must maintain alignment on their common axis as they move around your work space.

               

              For a 4-bar linkage pins would be the way to go to get all the bars linked together.  You don't necessarily need No Penetration contacts as the definition of the pin can keep the holes aligned as well as maintain the axial spacing of the holes.  So, if you are looking for a quick analysis setup you could avoid the slowness that comes from No Penetration contacts by using the "With reaining ring" option in the pin definition.