20 Replies Latest reply on Dec 14, 2016 6:50 AM by Pedro García

    Curvature 3D splines problems 2008 and 2016 version... 

    Pedro García

      Hello everyone, i am new in this forum (sorry for my english), my name is Pedro Garcia, I am from Brazil and this year, owner of a toy factory called JPBrink, i work with solidwork since 2005 making toys projects (i was 14 years old), i stoped in solidwroks sw2008, so this year i decided buy and upgrade to solidworks 2016 licence, and now i am very frustrated, i have the same issues that i had in sw2008 and my work involve 90% surface usage. some of my works made in SW2008:

      Baby Driver render A.jpgCogumelo render.jpg Ratinho Render.jpg

      UPDATE 10/17/16 ( 04 Curvature continuous problem... file)

      Another example of 3D spline for utility that can not currently be used:

      The intersections or boundary between surfaces shown in the picture below are in tangency condition to be able to build a curvature surface must first be placed endpoints in continuous curvature ::

      sugestão para select manager 07.jpg

      To do this, I replace the fillets to fillets curvature continuous, extended the surfaces and made a 2D spline curvature condition and trimmed the surface, the result was a very smooth surface curvature continuous using bondary surface.

      sugestão para select manager 08.jpg sugestão para select manager 09.jpg

       

      But when I try to do the same thing but in a situation of curved surface is not possible to place the curvature relations using surface splines:

      sugestão para select manager 10.jpg

      i really do not understand why this rhappens.

       

      The problem (tail curvature... file)

       

      I need to do a animal tail, this is the situation (made in SW2016):

      tail.jpgcurvature Pedro problem 05.jpg

      I did the face split/lines using 3d splines on surface (the blue lines)

       

      I am having a problem with curvature surface with spline continuous, for some reason the curvatures is inverting (inflection) next to the final point:

      curvature Pedro problem.jpgcurvature Pedro problemb.jpg

      So if i set to tangence its look fine, (like in solidworks2008):

      curvature Pedro problem tangence.jpgcurvature Pedro problem tangence b.jpg

       

      I thought that was a possibility to the main surface has some curvature problem but don't have any inverted curvature:

      curvature Pedro problem 03.png

      I know that have a lot others ways to fix that, for eg, add more two controls lines and make the splines curvature from that and drawing it in 2D planes, but i dont undestand

      why this happens with 3D splines.

      e.g:

      I should do something like that with guided lines to do smooth surfaces:

      curvature Pedro problem 12.jpg

      I can do curvature from 2D planes with any problem, but i really want now why 3D splines can't :

      curvature Pedro problem 2D plane.jpg

       

      Another problem i can't convert/duplicate 3D surface splines in sw2008 i can,

      another Topic about this problem:

      (2015 and later can not copy / convert a 3dsketch on surface, 2014 and older can. (why?) ):

      Pedro Garcia - converter esboço 3d inativo.jpg

      I draw using 3D surface splines, because is easyer to me see point cloulds (imagem above), SW16 dont had big improvimentes in "scan to 3D"

      for curve wizard too, i can do only 2d curves sections with that like in SW2008, again any big improviments here.

      We can't create relations using two "surface 3D splines"

      Surface splines not accept any relation from any 3D sketch object

      e.g. points or final lines points...

      curvature Pedro problem 13.jpg

       

       

      UPDATE 10/12/16 ( 02 tail curvature... file )

      I uploaded a new model, I tried replace main surface using loft surface, and I made

      the curvature continuous splines using 2d planes.(image above with zebra stripes)

      curvature Pedro problem 06.jpg

      but I still having problem with spline 3D curvature (red line).

      i tried just set curvature continuous (selecting spline/plane/endline) without a line split in surface, but with this method i don't have

      a really good control for the direction tha spline gona out from surface, but nether this method i have good curvature out, see image below:

      curvature Pedro problem 07.jpg

       

      i know that i can close my eyes and accept this because my job is with toys, not with automobilistic things, (i had done the tail):

      curvature Pedro problem 10.jpg

      but i thought that I gonna have big improviments for surface and anylises tools upgrading my SW2008, because it was almost 10 years of development, and i do not understand why they didn't improve the software to do better continuous surfaces (maybe i am wrong or maybe SW team don't want improves this for some reason,).

       

      UPDATE 10/13/16 ( 03 tail curvature... file)

      I tried another thing:

      extend the main surfaces, split them and convert into 3d sketch:

      curvature Pedro problem 12.jpg

      theoretically the splited surface lines should be continuous,

      but nether with this method i can do 3D curvature continuous with 3Dsplines:

      curvature Pedro problem 11.jpg

       

      Thanks you guys for the help and i still waiting an official solution.

      Sorry for my english.

        • Re: Curvature spline problems 2008 and 2016 version... 
          Christian Chu

          You don't need to use 3D spline for split line, but 2D split line instead

          I just added a 2D spline to match your 3D one

           

          Capture.JPG

          Capture 2.JPG

          • Re: Curvature spline problems 2008 and 2016 version... 
            Paul Salvador

            Pedro,... yep.. it has changed and is different from where you left off... for this, apply the spline curvature first to the surface then move the endpoint to your split.   (btw,.. nice surfacing work you show above!!)

            edgefacesplineequal.pngcurvatsurf.png

            • Re: Curvature spline problems 2008 and 2016 version... 
              Pedro García

              Thank you guys,

              Paul Salvador i tried your tip to add relation fisrt and than move the point, but for me this is wierd because if i add "curvature equals"  the splines still can be free moved breaking again the curvature surface...see below

              curvature Paul way test.jpgcurvature Paul way test2.jpg

              i think that i am doind something wrong maybe...

                • Re: Curvature spline problems 2008 and 2016 version... 
                  Paul Salvador

                  Pedro,.. understand and as you know you can try other workarounds but since things have changed... another option to consider is using Boundary Surface,.. it works well for something like this.

                    • Re: Curvature spline problems 2008 and 2016 version... 
                      Neil Larsen

                      on SW2009 myself so I am not a lot of help... but isn't there really a bug or at the least undesirable behaviour going on there? Why should you have to slide a relation into place to avoid it crapping out if you endeavour to construct it directly/intuitively and why does it flip curvature orientation? If the spline code has some ambiguity in the way it resolves surely the user should have the option in the UI to 'flip orientation' or such so you can specify what you want. Right click on and... I gather this issue is occurring because the edge somehow messes up the evaluation of the tangency, perhaps its because the trim cuts the underlying sheet/patch obliquely? Seems like something that ought to work better than it does presently...

                        • Re: Curvature spline problems 2008 and 2016 version... 
                          Paul Salvador

                          Neil,..

                           

                          YES... you would think by NOW (>20 years for this program!?).. we would experience some consistency or LESS CHAOS.... but ... NADA!

                           

                          2D and 3D Spline have changed often over the years and per service pack..  and it is NOT easy for most of us to understand or get consistent handle on their behavior.

                           

                          ... currently, not sure if what I'm seeing are bugs or what I think it is,..  inconsistent/unfinished/inprocess spline components for us users or "beta testers" to send back to SW Corp so they do not have to pay anyone to test?

                           

                          WOULD BE GREAT IF WE HAD A OFFICIAL CHART ON ALL the 2D and 3D ALGORITHMS which have been applied to SW 1995-2017... information to help everyone on how/what was added/changed.. on the issues, behaviors and recommendations with splines per release? 

                           

                          Anyhow, it clearly has been a GREAT business model for SW Corp and D-Cubed!

                           

                          ..

                            • Re: Curvature spline problems 2008 and 2016 version... 
                              Neil Larsen

                              Yeah I am inclined to think there is something incomplete or not considered there too. A missing or extra line of code required of the nature 'if x or y then' or such.

                              Pedro should probably turn it in as a bug - if he can be bothered - seeing as how doing so often doesn't result in a very timely or satisfactory resolution.

                              As you say with all the changes that go on behind the scenes and for no apparent reason it leaves the user a bit nonplussed as to whether things are intended or broken or....and of course there is no notification. This has long been a SWX weakness (as have things for which there are no help notes - but that's another topic).

                              For the users who make serious use of surfacing it would indeed be handy to know what areas have been 'refined' by the golden touch of programmers lately and why. It is often quite important to preserve a surface model just as it was created or at least to be aware of a subtle change that may have taken place. It would be certainly be possible to make an expensive mistake with tooling if there where unknown inconsistencies say between service packs never mind the time and inconvenience of reworking something to avoid a suddenly emerged issue.

                              Most likely as a private contractor you have been in the situation of seeing the profitability vanish on a job because SWX created a whole lot of work for you in their endeavour to silently fixing something you didn't know was broken and may have not have been anyway. Compulsive Obsesssive Code Tinkering - Unknown Purpose (COCT-up) I would call it.

                              SWX folk ought to consider any and all spline or surfacing maintenance to be of potential interest to users and publicise it.

                              When Mark B. was around he probably would have looked in to this thread and had something to say about the nature of the issue. Today I am afraid users end up voicing their concern/dissatisfaction among themselves and probably to little or no effect...

                      • Re: Curvature spline problems 2008 and 2016 version... 
                        Paul Salvador

                        Maybe SW Corp or D-Cube can answer,..... since,.. it is their program(s) and JOB!?............. ????????????????????????????

                        • Re: Curvature spline problems 2008 and 2016 version... 
                          Mark Biasotti

                          Hi Pedro,

                           

                          I've seen similar issues and it is because of a combination of the constraint solver and conflicting constraints being placed at the endpoint of 3D splines. I have two recommendations for you; first, use Style Spline (introduced in 2014) for any spline that is greater than a 2 point spline (if possible.) They are Bezier and much higher quality than you can get with multipoint through-point splines. Also for legacy work in 2016> you can convert a through-point to a style spline and vice-versa.  Second, I use the face Tangency and Face curvature constrains on 3d Splines which are less likely to over constrain. These two constraints are rather undiscoverable in that you need to preselect the spline then the edge that it is attached to and then the adjacent face, only then will they show up in the shortcut popup or PM.

                           

                          Like your toy work, we too here at Spanner are involved with GreenToys in which we've had to execute a lot of SW surfacing.

                           

                          Mark

                            • Re: Curvature spline problems 2008 and 2016 version... 
                              Pedro García

                              Thank you Mark Biasotti for your response,

                              and very nice toys that your team make!

                              I remember that brand grentoys, i saw them in toys fair in Nuremberg this year and it was a very nice experience to me!

                               

                              About SW, i gonna try to use you tips, but this is a shame, after almost 10 years that we have to find quick fixes to make good surfaces that could be much easier and fast...

                               

                               

                               

                              Paul Salvador

                              i was looking about CREO, and in this vídeo the user makes continuous splines from surface much easy and fast at 9:10, Creo Car Tutorial Toyota 86 - Part 9 Creating the back wheel arch blends - YouTube

                              and true free-form tool

                              Creo Shoe Tutorial 3 - Overall Shape with Freestyle - YouTube

                              anybody can tell me if inventor is better for surfacing and mold design?

                              Inventor Freeform 2016 - YouTube

                                • Re: Curvature spline problems 2008 and 2016 version... 
                                  Paul Salvador

                                  Pedro,.. I worked with Creo 1.0 and beta of 2.0.. I did not do much with Freestyle.. I would say, not much production.. and at the time I felt I better with using what I knew for the project (eyewear).

                                  Splines in Pro/e or Creo are much more consistent.. or more manageable, imho,... I rarely experienced extreme behavior as I see with SW Splines.

                                   

                                  I know very little about surfacing in inventor. 

                                   

                                  btw,.. in the toyoto video 15:20, he says, play around with it.. this is true for SolidWorks as well.. nudging the end point or slightly changing the curve or surface can give you a desired result... again, not consistent... suggest locking the feature after you get what you need!

                                   

                                  also, consider the addin Power Surface  (similar to Freestyle)   I have not used it but have seen some good results for early layouts.

                                • Re: Curvature spline problems 2008 and 2016 version... 
                                  Neil Larsen

                                  Hi Mark thanks for stopping by with the very useful answer. If I ever knew about this particular issue I have forgotten about it....'rather undiscoverable' well what can I say....  I wish someone would gather up all of these insider tips into a special help for surfacers. Perhaps you would consider putting together a booklet or pdf for sale? I am sure you would find more than a few buyers.

                                  I gather then the solver/constraint issue is a limitation rather than some situation not addressed fully but perhaps it could be handled better. The recommendations you provided aren't something you are going to come up with yourself sitting in front of it but rather like Pedro you will be defeated by the behaviour. Maybe there should be a popup message to say 'the constraints applied to the endpoint may not provide the desired geometry see Surfacing Help' or such. Really though I would have thought it would go 'over-constrained' or 'unsolvable' rather than be allowed to solve oddly/unhelpfully given that most people would be looking to make some sort of continuity. IMO there is just too much involved here that is beyond the awareness of the typical user and cant easily be presented in the UI.. Hopefully the person who manages this area presently will see the thread and consider some refinement/change or perhaps give their blessing to a Surfacers Help written by someone with inside knowledge.

                                  Thanks again for sharing your insight with the community.

                                    • Re: Curvature spline problems 2008 and 2016 version... 
                                      Mark Biasotti

                                      Hi Neal,

                                       

                                      I use SW, Creo and Rhino here at Spanner but most of my projects are SW - all have their particular issues. While at SW, Rob Jost and I worked hard (mostly Rob who was PD on it and responsible for its definition - he did an excellent job!) on the Style Spline which I wanted to put in place of the thru-point spline spline for many years. It is a worthy successor but doesn't completely replace it.

                                      If I recall, SW uses a different constraint solver for their 3D sketch than their 2D. This is wherein the problem lies. It is particularly not good on SOS (Spline on surface) but SW developers have made this feature better than it was (I think in SW2015.)  What you have to look for in 3D sketch splines is that they can easily over constrain because, for some reason, competing constraints are placed where you make the endpoints of the spline coincident with an existing external vertex (i.e. surface vertex or edge endpoint.) Having the show>sketch relationship on helps to identify these dual constraint issues. Then it is a simple matter of deleting one of them.

                                       

                                      Really though I would have thought it would go 'over-constrained' or 'unsolvable' rather than be allowed to solve oddly/unhelpfully given that most people would be looking to make some sort of continuity.

                                       

                                      When there is obvious non-tangeny happening (even thou a seemingly proper constraint is applied) there is a problem but no error indication and I think this is a bug. What is worse, is that thru a rebuild, it becomes a visible error. What I have to do sometimes as a work around is to create a construction line at the vertex of the spline and the geometry and make the construction line tangent to the external edge. Then I apply tangency between the spline and the construction line.  This seems to always work.

                                       

                                      Mark

                                        • Re: Curvature spline problems 2008 and 2016 version... 
                                          Pedro García

                                          thanks Mark Biasotti  and Neil Larsen to help us again,

                                          with tangency i never had problems using that too, it works very well in SW, but i am corious guy...

                                           

                                          i know the right construction lines to my model should be something like this to make a very smoth surfaces :

                                          curvature Pedro problem 12.jpg

                                           

                                          but, i tried another method but i didn't have good results:

                                          i tried extend the surfaces/ split / convert lines into sketch and merge them with splines...

                                          curvature+Pedro+problem+12.jpgcurvature Pedro problem 11.jpg

                                          unfortunately no good results...

                                           

                                           

                                          so, that is it, we need give up, and be happy to use only tangency, (like in sw2008/2005...) maybe in SW2030 we can use 3d splines curvature continuous...

                                      • Re: Curvature 3D splines problems 2008 and 2016 version... 
                                        Ryan Feeley

                                        Insightful discussion. Regarding this comment from Mark:

                                         

                                        "Second, I use the face Tangency and Face curvature constrains on 3d Splines which are less likely to over constrain. These two constraints are rather undiscoverable in that you need to preselect the spline then the edge that it is attached to and then the adjacent face, only then will they show up in the shortcut popup or PM."

                                         

                                        Does this actually work with the style spline? In my experience (mainly SW2015 SP05) you can create a face curvature relation on a 3D style spline, but the solver doesn't use it. Interestingly, if you then convert the style spline to a B-spline, the relation will be enforced. But you loose all the niceness of the style spline. Perhaps I'm just doing something in the wrong order, but I don't think that's the case.

                                         

                                        I think this is what Pedro was referring to when he said:

                                         

                                        "i tried your tip to add relation fisrt and than move the point, but for me this is wierd because if i add "curvature equals"  the splines still can be free moved breaking again the curvature surface".

                                         

                                        Thanks!

                                        Ryan

                                      • Re: Curvature 3D splines problems 2008 and 2016 version... 
                                        Mark Biasotti

                                        Pedro the contraint method I outlined should work well for C2 also. Also, you will be more successful with style spline and C2 - as long as you increase it to a higher order (increase polynomials)