8 Replies Latest reply on May 24, 2018 6:26 AM by Jim Moses

    Solidworks 2018 flexible mates and flipping mates ???

    Jim Moses

      Hi all,

       

      I have a sub-assembly with flexible mated sub assemblies in it, now every-time I add a component or a mate I get a error and come to find my mates flipped for no reason, as  it was fine with no errors until I either add something, not even a mate.  I seem to have this happen even if I add a feature to a weldment in my assembly, like an additional plate to mount something off of.   Also having to change things from flexible to rigid and back again to get the errors to clear which does not always work.

       

      I am currently trying to mate handle in my assembly that have the dreaded ball point to point connections. I tried adding a sketch to constrain them too but this again flips out mates not even related.

       

      This version of Solidworks has cost me more time than I care to count, attempting to do something I could do relatively easy in 2016 so not sure what setting I am unaware or what else has changed, but it is getting to the point of remodeling everything in 2016 almost seems easier, and I know that can't be the correct answer.

       

      So any ideas on where to look or setting I may have overlooked?

       

      Regards,

        • Re: Solidworks 2018 flexible mates and flipping mates ???
          Dennis Dohogne

          Jim Moses wrote:

           

          Hi all,

           

          I have a sub-assembly with flexible mated sub assemblies in it, now every-time I add a component or a mate I get a error and come to find my mates flipped for no reason, as it was fine with no errors until I either add something, not even a mate. I seem to have this happen even if I add a feature to a weldment in my assembly, like an additional plate to mount something off of. Also having to change things from flexible to rigid and back again to get the errors to clear which does not always work.

           

          I am currently trying to mate handle in my assembly that have the dreaded ball point to point connections. I tried adding a sketch to constrain them too but this again flips out mates not even related.

           

          This version of Solidworks has cost me more time than I care to count, attempting to do something I could do relatively easy in 2016 so not sure what setting I am unaware or what else has changed, but it is getting to the point of remodeling everything in 2016 almost seems easier, and I know that can't be the correct answer.

           

          So any ideas on where to look or setting I may have overlooked?

           

          Regards,

          Jim, I have had this happen for many versions of SWX, at least from 2013-2018 so reverting to 2016 won't solve it.

           

          First and foremost you need to make some noise with your VAR about this so they can collect data and send it to SWX.  I've seen enough of this and talked with some folks at SWX that are responsible for the whole area of mates and learned a little about how difficult and complicated this can be.  I don't care; I just want it to work.

           

          There are some things you can do to ease the pain (less frequent occurrence):

          1. Keep the subassemblies rigid except when you need to exercise the mechanism.  Especially keep them rigid during the addition of new parts/assemblies and when creating new mates.  It shouldn't matter, but it does.

          2. As much as possible put your flexible mates (limit distance and limit angle mates) as high in the assembly hierarchy as possible.  I have cylinder subassemblies typically setup with three configs: Retracted, Extended, and Stroke, where the last one has a limit distance mate allowing the rod to move between the retracted and extended limits.  After dealing with these problems I am now adding a fourth configuration, Free, where the limit distance mate is suppressed.  The stroke limit is then achieved in a higher assembly, preferably the top-most assy.  The trick here is that you must mate a moving part of the cylinder to something outside of the cylinder subassy, but that usually is not too hard.

          3. Look for ways to make a mate that cannot flip.  Tangent and parallel mates can easily flip and limit mates can be overrun if you move something too fast.  Instead of a tangent mate, for instance, I might pick the surface and the center point or axis of the curved surface and use a distance mate.  These don't flip.

           

          I have pushed this with my VAR, but because I'm not screaming at them about this every week they aren't doing anything about it.  They've seen it happen on my machine, but I cannot always reproduce it so it is hard to pin down what is actually happening.  I suspect it has something to do with a cache for the rebuilds or calculations not clearing, but we really need the SWX folks to dig into this.

           

          PLEASE do make a stink about this with your VAR and push them to send it to the folks at SWX.

            • Re: Solidworks 2018 flexible mates and flipping mates ???
              Dennis Dohogne

              1-GMJYC8 wrote:

               

              Jim Moses wrote:

               

              Hi all,

               

              I have a sub-assembly with flexible mated sub assemblies in it, now every-time I add a component or a mate I get a error and come to find my mates flipped for no reason, as it was fine with no errors until I either add something, not even a mate. I seem to have this happen even if I add a feature to a weldment in my assembly, like an additional plate to mount something off of. Also having to change things from flexible to rigid and back again to get the errors to clear which does not always work.

               

              I am currently trying to mate handle in my assembly that have the dreaded ball point to point connections. I tried adding a sketch to constrain them too but this again flips out mates not even related.

               

              This version of Solidworks has cost me more time than I care to count, attempting to do something I could do relatively easy in 2016 so not sure what setting I am unaware or what else has changed, but it is getting to the point of remodeling everything in 2016 almost seems easier, and I know that can't be the correct answer.

               

              So any ideas on where to look or setting I may have overlooked?

               

              Regards,

              Jim, I have had this happen for many versions of SWX, at least from 2013-2018 so reverting to 2016 won't solve it.

               

              First and foremost you need to make some noise with your VAR about this so they can collect data and send it to SWX. I've seen enough of this and talked with some folks at SWX that are responsible for the whole area of mates and learned a little about how difficult and complicated this can be. I don't care; I just want it to work.

               

              There are some things you can do to ease the pain (less frequent occurrence):

              1. Keep the subassemblies rigid except when you need to exercise the mechanism. Especially keep them rigid during the addition of new parts/assemblies and when creating new mates. It shouldn't matter, but it does.

              2. As much as possible put your flexible mates (limit distance and limit angle mates) as high in the assembly hierarchy as possible. I have cylinder subassemblies typically setup with three configs: Retracted, Extended, and Stroke, where the last one has a limit distance mate allowing the rod to move between the retracted and extended limits. After dealing with these problems I am now adding a fourth configuration, Free, where the limit distance mate is suppressed. The stroke limit is then achieved in a higher assembly, preferably the top-most assy. The trick here is that you must mate a moving part of the cylinder to something outside of the cylinder subassy, but that usually is not too hard.

              3. Look for ways to make a mate that cannot flip. Tangent and parallel mates can easily flip and limit mates can be overrun if you move something too fast. Instead of a tangent mate, for instance, I might pick the surface and the center point or axis of the curved surface and use a distance mate. These don't flip.

               

              I have pushed this with my VAR, but because I'm not screaming at them about this every week they aren't doing anything about it. They've seen it happen on my machine, but I cannot always reproduce it so it is hard to pin down what is actually happening. I suspect it has something to do with a cache for the rebuilds or calculations not clearing, but we really need the SWX folks to dig into this.

               

              PLEASE do make a stink about this with your VAR and push them to send it to the folks at SWX.

              I just got this message from our friend, John Stoltzfus

              "This is all good stuff, but – the answer in my book lies in this thread -  The 11th Weekly Power-User Challenge (October 20th, 2017): Flipping Mates - Robot Case Study  - one of Alin’s challenges that deals with flipping mates..  I have used a Spline Line and a Sketch Point with 100% success, I am hoping like crazy that SW bumps my Enhancement request so we can mate right to a sketch line or a set of sketch lines.  If that were to happen it would eliminate the Width & Limit Dimension Mates.    There is a SPR listed in that site – do us a favor and promote it

               

              Thanks,

              John"

               

              The SPR he is referring to is 1052441.  I found it on the Knowledge Base:

              https://customerportal.solidworks.com/customerportal_enu/start.swe?SWECmd=GotoView&SWEView=SW+OUI+All+Defects+List+custo…

               

              You can go to this KB article and add your name to the notification by sleceting this button:

                • Re: Solidworks 2018 flexible mates and flipping mates ???
                  Matt Peneguy

                  Dennis,

                  Voted!

                  Thanks for adding the picture.  It is not clear at all to first time users how to "vote" for an SPR...At least it wasn't clear to me.

                  This is a big bug, and I agree it may be difficult to fix; but it definitely should be fixed.

                  • Re: Solidworks 2018 flexible mates and flipping mates ???
                    Jim Moses

                    I tried your Link and this is what I get, it gives me the following:

                     

                     

                    when I continue I get this:

                     

                     

                    I would be happy to promote any SPR that deals with mates, usually they are common fixes as I have been at this since 2003, but this every-other command get a error is getting old. it probably has something to do with history or cache that is not letting things go or rebuild correctly, or let the video card react correctly.

                     

                    these ball connections (Point to Point) are the worst to mate as I have yet to find a good method of keeping them mated as intended, as there is no Axis to defining the direction for such a connection.  This particular assembly has several of these connections so you can imagine the frustration level.

                     

                    Regards,

                  • Re: Solidworks 2018 flexible mates and flipping mates ???
                    Jim Moses

                    Hi,

                     

                    Thanks for the list, I have done most of this, just seems by now this would be fixed as I can't be the only one having this experience, and when things worked in my opinion better with the older versions of SW then I believe someone messed with something and yes I will see about getting the attention of my VAR and see what that does, though it doesn't help me get my job done.

                     

                    Regards,

                  • Re: Solidworks 2018 flexible mates and flipping mates ???
                    Rubén Rodolfo Balderrama

                    Sometimes you need to have the standard library in very good condition without repeating the component.

                    What to do SW, if a component is called equal in several assemblies, SW takes as valid only the first one.

                    Be cool with that, a good nomenclature of components helps eliminate this variable.

                    • Re: Solidworks 2018 flexible mates and flipping mates ???
                      Alex Lachance

                      Hey Jim,


                      Are you familiar with flexible assemblies/sub-assemblies? It sounds to me as if the flexible assemblies weren't fixed within their environment.

                       

                       

                      Some more tips to add to what Glenn said:

                      • Do not use ''lock rotation'' on parts mated with the flexible assembly, use a parallel instead.
                      • Tangent mates tend to flip themselves a lot
                      • If you're coming in off a fresh new SolidWorks session, I suggest putting the flexible sub-assembly to rigid and then back to flexible to refresh SolidWork's memory of the flexibility.
                      • Re: Solidworks 2018 flexible mates and flipping mates ???
                        Dan Golthing

                        Jim, you must be mistaken.

                         

                        I was specifically told somewhere around 2003-2004 that the mate flipping issue had been resolved.

                         

                        Therefore, what you are witnessing and what myself and everyone else has witnessed since then must be some other phenomena.