34 Replies Latest reply on Sep 7, 2018 9:15 AM by X. Liu

    Edge Ripples in Boundary Surfaces

    Luke Mastrangelo

      Hey y'all,

       

      I have a specific question and was wondering if anyone else has encountered and learned a repeatable solve for this issue:

       

      I would say 90% of my SW model building revolves around setting up and creating smooth surfacing (and then battling the heartburn). Sometimes when I create a Boundary Surface (with either Tangent or Curvature edge conditions ON) I get these odd ripples, always near the seam of the surfaces. I've attached an image that I've cropped for confidentiality reasons, hopefully this is illustrative enough.  These ripples appear in the final model despite being small scale, and despite my best efforts of adding guide curves to aid the profile in smoothly flowing, the ripples will appear elsewhere in the surface.

       

      So far my only fix in some cases has been to resort to Rhino 5, where I cut away and patch the holes smoothly then take the model back to solidworks (which is a horrible workflow)  Currently running SW 2017. 

       

      Overall this begs a bigger question which I've wondered since I've started using the software, which is why bother adding a "curvature continuous" checkbox in the Feature if it's essentially (visually) not curvature continuous?

       

      - Luke

        • Re: Edge Ripples in Boundary Surfaces
          Charles Smith

          Start by setting the tangency influence percentages to a lower number, and then work up a bit.  You can't have all 4 edges 100% tangent without ripples elsewhere on the surface.  Also the curvature option is more demanding than the tangency option, and it more likely to fail.

           

          Frankly, in the 12+ years I've used this software, I'm in agreement with you that the curvature and fillet options are somewhat weak.  If this was CATIA, we'd have a boatload more options.  As it is, stock up on Pepto Bismol.  :-/

          • Re: Edge Ripples in Boundary Surfaces
            Paul Salvador

            Hello Luke,.. for as long as I can recall, it has been a constant battle, struggle with tweaking the boundary conditions.

            One of the things you learn is to create helper curves or surfaces to aid the flow between the boundaries.

            As it is, the ripples are unacceptable and there should be greater control with tolerance and influence along the boundary to achieve a clean surface.

            High-end surfacing (class A) in SW is NOT and will most likely NEVER be a priority for Dassault Systemes.

            • Re: Edge Ripples in Boundary Surfaces
              X. Liu

              Hi Luke,

               

              I am the author of the "XNurbs releases the most powerful and easiest-to-use NURBS software" thread in SolidWorks Forum (XNurbs releases the most powerful and easiest-to-use NURBS software ). I would like to show Paul Salvador that "XNurbs can solve all kinds of problems SolidWorks may have in surfacing creation.". Could you send your model to us (support@xnurbs.com)? I will show in my thread how easy it can be done. I only need the surrounding geometries.

               

              If you would like to try XNurbs yourself, could you send me the image generated by XNurbs (you can crop the image for confidentiality reasons)? I will then post it to my thread. Please let me know how you would like to get the issue solved. Many thanks.

                • Re: Edge Ripples in Boundary Surfaces
                  Dave Bear

                  Hi X. Liu,

                   

                  How do you think that solving this single issue will prove to Paul that your product lives up to it's BIG title?

                  I have been following the other thread with much interest and to be honest I think you are over-inflating the claims of your product or belittling the knowledge held by those who challenge it's worth.

                   

                  Yes, you can solve this issue perhaps, but it doesn't really prove as much as you'd like to think..........

                   

                  Dave.

                    • Re: Edge Ripples in Boundary Surfaces
                      X. Liu

                      Hi Dave,

                       

                      Luke Mastrangelo mentioned "creating smooth surfacing (and then battling the heartburn)". So he should have a lot of cases. Let's assume XNurbs can solve all kinds of problems Luke Mastrangelo has, then it should mean something.

                       

                      I worked in R&D department for a big CAD company in the past, so I clearly know where they are. For SolidWorks users, after seeing our video, they might try to challenge XNurbs (they are not mathematicians and don’t know what the video really means). For professional developers, after seeing our video, they won't challenge us.

                       

                      Many thanks for your kind reminding.

                       

                      Kevin

                  • Re: Edge Ripples in Boundary Surfaces
                    X. Liu

                    Hi Luke,

                     

                    The problem is caused by inherent limitations of NURBS: Boundary Surfaces are based on the ordinary NURBS, which itself is made of a four-sided patch (like A4 paper). To represent the surface shown in your image, the four-sided surface must be distorted to a circular shape. The ripples come from the distortions, and the four corners (of A4 paper or near the seam of the surfaces) are the most serious.

                     

                    We can easily solve all kinds of problems you may have in surfacing creation. Could you send your models to us or send us the images generated by XNurbs (in case you would like to fix them yourself using XNurbs. You can crop the images for confidentiality reasons)?

                     

                    No need to "battle the heartburn" as you said anymore.

                     

                    Kevin

                    • Re: Edge Ripples in Boundary Surfaces
                      X. Liu

                      Please read this thread “XNurbs - further investigations ”. Are you willing to share some models or images? I think you have a number of issues with SolidWorks own tools. We should be able to solve all kinds of problems you have and silence Paul (just kidding with Paul).

                        • Re: Edge Ripples in Boundary Surfaces
                          Paul Salvador

                          Here, X. Liu.. dude,,.. I like what xnurbs can do... but, if you want a challenge for xnurbs programming,.. please show how xnurbs can do the examples attached,  (this can be done using standard boundary).

                           

                          again,.. just trying to get some content to understand how this makes sense for many of us as a 3rd party add-on.

                           

                          Oh,.. BTW,.. where can I get my FREE license (that you offered) for using BOTH Rhino3D and SolidWorks? 

                          xns-bndry-examples.png

                            • Re: Edge Ripples in Boundary Surfaces
                              X. Liu

                              Paul,

                               

                              We intend to solve all your models with one strike. We hope you have more models and send them together.

                               

                              FYI, I don’t understand why you sent those models. For example, your “xns-boundary-examples-zxys.SLDPRT” twists horribly. (The attached Paul.x_t is a part of your model so that you can clearly see the problem. Why do you only apply tangent continuity?)  The attached XNurbs.x_t is the same part generated by XNurbs, and we apply curvature continuity.

                               

                              Paul.png

                                • Re: Edge Ripples in Boundary Surfaces
                                  Paul Salvador

                                  X. Liu,.. I look forward to how you guys can patch (either tangent or continuity) the 3 above examples using xnurbs... thank you.

                                    • Re: Edge Ripples in Boundary Surfaces
                                      X. Liu

                                      For your examples, splitting it into (multiple) patches would be a better solution. We made a quick run for your example, and the following shows the results of using a single surface.

                                       

                                      Lofting2.png

                                       

                                      The surfaces are generated by the “raw” version of variational lofting. Of course, they are better than your results (As pointed out above, your models twist horribly.). However, the “raw” version does not meet the design intent (marked in the images). The “optimized” version of variational lofting should directly generate surfaces satisfying the design intent, but I don’t think you have a chance to see it.

                                       

                                      Could you kindly tell me why you think “xnurbs will forever only be a better Fill Surface”? For quite a while, we have been waiting SolidWorks’s approval to release V2 – From Dassault's viewpoint, xNURBS may be a quite complex application (please read my response to XNurbs - further investigations ). We would hope we could extract some useful info from your comments and submit to SolidWorks to speed up their discussion.

                                        • Re: Edge Ripples in Boundary Surfaces
                                          Paul Salvador

                                          Hello X. Liu .. I'll need that Free License you promised for me to evaluate.

                                            • Re: Edge Ripples in Boundary Surfaces
                                              X. Liu

                                              Paul,

                                               

                                              At the very beginning of xNURBS release, we did provide some free copies to the selected parties per their request, e.g., SolidWorks. We are picky who is qualified to get the free copy and that offer is only available for very short period of time.

                                               

                                              It appears that we created an over-powerful addin, and Dassault is a bit too careful for our application. Dassault is fully aware xNURBS’s capacities and the technology powering xNURBS, so they won’t be fooled by your comments. However, we would hope to make up something from your comments to speed up their discussion.

                                                • Re: Edge Ripples in Boundary Surfaces
                                                  Paul Salvador

                                                  "..so they won’t be fooled by your comments."

                                                   

                                                  Wow.

                                                  • Re: Edge Ripples in Boundary Surfaces
                                                    Dave Bear

                                                    X. Liu wrote:

                                                     

                                                    Paul,

                                                     

                                                    At the very beginning of xNURBS release, we did provide some free copies to the selected parties per their request, e.g., SolidWorks. We are picky who is qualified to get the free copy and that offer is only available for very short period of time.

                                                     

                                                    It appears that we created an over-powerful addin, and Dassault is a bit too careful for our application. Dassault is fully aware xNURBS’s capacities and the technology powering xNURBS, so they won’t be fooled by your comments. However, we would hope to make up something from your comments to speed up their discussion.

                                                     

                                                    So now you renege on the offer that was originally made to Paul, how very unprofessional. Did you not set aside the copy you had offered him at the time, or allocate one for him? Also unprofessional. Is the price of your product as expensive as the tickets you sell on the claims you make of it?

                                                     

                                                    I think that your overall comment (quoted above) actually probably highlights why Dassault hasn't dealt with you yet rather than the product itself, just my opinion (I do not speak on behalf on Dassualt).

                                                     

                                                    I can only imagine how a customer might get treated if they were to dare to actually ring your customer support and complain about your product.

                                                     

                                                    This is shameful..........

                                                     

                                                    Dave.

                                                      • Re: Edge Ripples in Boundary Surfaces
                                                        X. Liu

                                                        We never promised Paul a Free License! Could Paul please tell me when and how we made such a promise?

                                                          • Re: Edge Ripples in Boundary Surfaces
                                                            Dave Bear

                                                            X. Liu wrote:

                                                             

                                                            We never promised Paul a Free License! Could Paul please tell me when and how we made such a promise?

                                                             

                                                             

                                                            If you didn't make such a commitment then why have you made this statement?

                                                             

                                                            "At the very beginning of xNURBS release, we did provide some free copies to the selected parties per their request, e.g., SolidWorks. We are picky who is qualified to get the free copy and that offer is only available for very short period of time."

                                                             

                                                            I have followed with interest the various exchanges between yourself and Paul and can vouch that you did indeed make such a gesture!

                                                            Could it have possibly been inadvertently deleted?

                                                             

                                                            It is fine for you to promote your product as you see fit, albeit without any endorsements as yet from external references and only self promotion. Paul has in no way influenced my comments, you have.

                                                             

                                                            Please do not treat me as a fool. I am far from such. I have not said that your product holds no worth, but I will question ethics when I see that they indeed need questioning.

                                                             

                                                            With respect,

                                                            Dave.

                                                              • Re: Edge Ripples in Boundary Surfaces
                                                                X. Liu

                                                                What? We were just polite to say that “Paul, you may miss the very short period of time”. I think It is better than “Paul, we don’t think we made you such a promise!”

                                                                • Re: Edge Ripples in Boundary Surfaces
                                                                  X. Liu

                                                                  I check the various exchanges with Paul. Indeed, Paul asked us several times for the free copy and always use the same way "we promised him a free copy". So you assume that we did make such a gesture! But the question is we NEVER made him such a promise!

                                                                    • Re: Edge Ripples in Boundary Surfaces
                                                                      Paul Salvador

                                                                      Amazing... .it took you a while,.. and you finally came to the same conclusion as I... it was based on your original initial offer made by you/your company... if had/used both Rhino3D and SolidWorks you offered a FREE License,.. and, I had "asked" for a license multiple times... and I had made many efforts to share examples with you,..  and yes, you have absolute the right to choose who you want,.. I have no problem with that... and honestly, I wish you the best, seriously.   Kind of reminded me of the classic... carrot/stick/bait/switch.. classic PTC sales move?

                                                                      I personally agree with you though, they are a concerned with your past connections and you have something which is good,.. although, I think SW Corp is a PITA... but most likely are freaking out you have some past contract/conflict which will place them over a legal barrel.

                                                                      BTW,..  as a past Pro/e Surfacing v9-Creo1  user >14yrs  (which I luved using) I have to say you have reminded me of the past.. seems your PTC arrogance has not rubbed off much... and why most Pro/e users are using SW... sad.  

                                                                        • Re: Edge Ripples in Boundary Surfaces
                                                                          X. Liu

                                                                          Paul,

                                                                           

                                                                          Thank you for clearing it up. In that pre-release announcement we posted in Rhino Forum, we clearly stated "... A small number of users may get a permanent XNurbs license for free. If ... please contact us (to discuss it).". That offer opened only for a very short period of time. (Sometimes later, we found out that a reference must purchase the product, but if we promised anyone for a free copy, we kept our promise.)

                                                                           

                                                                          "...most likely are freaking out you have some past contract/conflict which will place them over a legal barrel."

                                                                          When I resigned from PTC, there is a written agreement about the ownership of the IP, which was signed by PTC and me and states clearly that I totally own the technique/kernel …

                                                                           

                                                                          I was educated in UK and got my Ph.D in UK, and then worked several years in Cambridge … Paul, you are not my boss, but sometimes, you are a bit curious about others personal info. Are you satisfied now? ;-)

                                                                    • Re: Edge Ripples in Boundary Surfaces
                                                                      Paul Salvador

                                                                      Yes.. you did NOT "promise" anything.... you feel better now?   I do.

                                                                    • Re: Edge Ripples in Boundary Surfaces
                                                                      Paul Salvador

                                                                      Hey Dave,.. thanks for the defense (appreciated).. but X. Liu  and his company have that right using whatever tactics to get where they want.   Yes, they originally gave a blank offer to Rhino3D/SolidWorks users..  I did make real modeling/comparing efforts and/also asked multiple times  but... .  I'm not surprised with X. Liu  past comments towards me or other users in this forum and/aslo the Rhino3D forum..,  just a bit cold/arrogant .. or maybe a past business creed/culture/education..  or PTC made him this way?

                                                                      Can't blame them.. they want to choose/select a specific "type of user and/or company" to control what is/not shared to best display the strengths of their product and possibly market them.  hmm,..almost sounds communist/nationalist... X. Liu ... do you work for the party??)

                                                                        • Re: Edge Ripples in Boundary Surfaces
                                                                          Dave Bear

                                                                          Hey Paul,

                                                                          I don't just stand up for my friends, I'll stand up when I think something is blatantly wrong or being portrayed as the fault of an innocent. Call it old school or whatever if you like. Maybe sometimes I should just mind my own business but in this world if we just turn a blind eye then the types I mention get the upper hand and I was raised better than that.

                                                                           

                                                                          Dave.

                                                                            • Re: Edge Ripples in Boundary Surfaces
                                                                              X. Liu

                                                                              Dave,

                                                                               

                                                                              I am afraid that you totally made a mistake this time.

                                                                               

                                                                              The “promise” Paul mentioned is a pre-release announcement we posted in Rhino Forum! It is not a promise for free copies! I can get the announcement if you are still confused.

                                                                              • Re: Edge Ripples in Boundary Surfaces
                                                                                X. Liu

                                                                                Dave,

                                                                                 

                                                                                Since you insisted "something is blatantly wrong or being portrayed as the fault of an innocent", here is the story (I am not trying to embarrass you):

                                                                                 

                                                                                The "promise" Paul mentioned is a pre-release announcement we publicly posted in Rhino Forum: "... A small number of users may get a permanent XNurbs license for free. If ... please contact us (to discuss it).". Weeks later, Paul found the post and then asked for a free license several times. We politely turned it down. Nothing wrong with that.

                                                                                 

                                                                                Then you jumped out and claimed we are unethical. You can even vouch that we did indeed make Paul a "promise". Both Paul and I confirmed that, except for the announcement publicly posted in Rhino Forum, there is not any other "promise". How could you vouch what you claimed?

                                                                                 

                                                                                Next time, when you condemn others unethical, please be sure that you understand what you are doing. No hard feeling ;-) Dave, you are a funny guy.

                                                                        • Re: Edge Ripples in Boundary Surfaces
                                                                          X. Liu

                                                                          Paul,

                                                                           

                                                                          You should not mislead others to believe that we promised you a Free License. As you can see Dave really believe what you said.

                                                                           

                                                                          You always want to know who we are. Since Dassault has fully investigated our history, so we don't mind to tell you:

                                                                           

                                                                          About Us

                                                                          People at xNURBS previously held senior R&D positions at PTC. After left PTC, more than a decade has been spent on the development of our variational surfacing kernel. In fact, ten years ago, established CAD companies (ISV) started to license our kernel and use it to develop applications for end users. Here is one of our kernel PR news related to nPowerSoftware in 2009 (now the kernel has a different name): http://www.digitaleng.news/de/integrityware-licenses-vbsplines-nurbs-library/.

                                                                          Now after years of R&D, we eventually solve the key issues in surfacing and start to develop end-user applications. We invite users to judge if xNURBS is the most powerful and easiest-to-use NURBS software ever developed."

                                                                            • Re: Edge Ripples in Boundary Surfaces
                                                                              Dave Bear

                                                                              X. Liu wrote:

                                                                               

                                                                              Paul,

                                                                               

                                                                              You should not mislead others to believe that we promised you a Free License. As you can see Dave really believe what you said.

                                                                               

                                                                               

                                                                              This statement has been addressed above..........

                                                                               

                                                                              Dave.

                                                                                • Re: Edge Ripples in Boundary Surfaces
                                                                                  X. Liu

                                                                                  Paul asked a free license in his last message. We were just polite to Paul and say “Paul, you may miss the very short period of time or SolidWorks is more qualified to get the free copy.”. I think it is better than “Paul, we don’t think we made you such a promise!”

                                                                                   

                                                                                  Since Dave made some mistakes, could Paul please tell me when and how we made such a promise? I am 100% sure we NEVER make such a promise to you!