3 Replies Latest reply on Jan 27, 2015 2:11 AM by Jared Conway

    problems with slot mates and linear motors in motion analysis

    Matthew Davis

      I've created a very simple pinned linkage with a slot. This linkage is being driven by a linear actuator that is connected to it via a slotted mate.  Everything works fine in animation, but in motion analysis, the slot mate gets "ignored" by the solver and it fails to solve.  I've tried both the mechanical slotted mates and the path mates with no success.  I've also treated the actuator components as both a flexible sub-assembly and native to the full assembly with no luck.  Is there a workaround I'm missing?

       

      I'm running SW 2014 Premium SP4.0

        • Re: problems with slot mates and linear motors in motion analysis
          Alan Thomason

          I had a similar problem last week in which I also tried both slot mates and path mates in motion with no luck.  At one point you might be given the option of using a path mate but only if you lock it to a fixed point, which is not useful.

           

          If you were not worried about where the endpoints were (like your travel is limited by the 'motor' movement), you could simply apply a coincident mate between the point at the center of your lug to the line I see in your path. This gives fast and reliable solve times but the lug can travel beyond the visible extents of the parts as defined by the slot.

           

          If you want the part to stop when it reaches the ends of the slot, then the only way I know to do this is to use contacts.  This is what I have done in my assemblies, and it works surprisingly well.  In your case you would not be able to simply put the contact in alone, the parts would need to be be supported by other mates because otherwise it would be too sloppy.  For instance, you would need to keep the faces parallel and you could probably still do the coincident mate between the point and your path line.

           

          If someone else with more knowledge wishes to chime in please don't be deterred by my having responded.

           

          Best of luck....

          • Re: problems with slot mates and linear motors in motion analysis
            Matthew Davis

            Alan,

             

            Thanks! That worked. I needed to limit the range of motion, so I had to use all 3 mates. Parallel, point-line coincident, and contact between the two parts.  I hadn't used those 3 in combination before.  I had thought parallel and contact mates would be enough.

             

            Matt