14 Replies Latest reply on Nov 8, 2018 3:13 AM by Dave Bear

    Draping a coil

    Bob Gooding

      Hello Friends,

       

      I've had a successful iteration of this part which is a study to try and estimate how a coil of cable will drape or hang in my project. But, by trying to alter it to more accurately follow my real world sample, I have stumbled on a strange phenomenon.

       

      As you can see below, I have twisted a surface along a spline to create a coiled path to sweep along (Thank you for helix-helix @Paul Salvador)... At one of my lower control points where the curvature of the spline has brought the loops into a possible interference, the sweep has jumped a revolution of the path! What strange magic is this?

       

      This is not super critical with respect to my model but I did want to get rough idea of where to place the holster for the IEC plug and the upshot would be a nice model for our marketing team to use in the full product renderings. The attached model is unfinished and configured to be Draped, Hung and As Drawn, where i will ultimately lay it flat and straight to describe it to our suppliers.

       

      Before I set off in that direction, could you offer some constructive comments on this approach and maybe I could simplify the method? (hoping for an avalanche )

       

      Warm regards, Bob

        • Re: Draping a coil
          Krzysztof W.

          Hello.

          This is the real world situation

          ...and now a little bit more serious.

          I have done it in the past. Simple sweep with revolutions control. 2019 part attached.

            • Re: Draping a coil
              Bob Gooding

              Thanks Krzystof,

               

                   I'm not struggling with this modelling concept, only how bizarre the maths is that calculated the jump between turns of the coil.

               

                   The main issue is my approach to this task?

               

                   I haven't got access to any cable routing add-ins so I'm configuring this part to do the two options "Draped" & "Hung" so that I can calculate the length of the tails to produce the third configuration which will flatten it out into something I can describe to our supplier on a drawing later.

               

              Many thanks, Bob

                • Re: Draping a coil
                  Deepak Gupta

                  Can you upload the model to see why it is behaving like that?

                   

                  You can also try creating a split in the spline to see if that helps.

                    • Re: Draping a coil
                      Bob Gooding

                      Please forgive me Deepak I thought I had attached the zip file... I've progressed it some more now so I'll upload them both for your perusal

                        • Re: Draping a coil
                          Deepak Gupta

                          Bob Gooding wrote:

                           

                          Please forgive me Deepak I thought I had attached the zip file... I've progressed it some more now so I'll upload them both for your perusal

                          No worries Bob, we have all gone thru that route.

                           

                          OK, I reset the spline handle on around that intersection and that seems to fixed the issue but I was not able to save the file. I'm trying that again and would share the result and file.

                          • Re: Draping a coil
                            Paul Salvador

                            Hello Bob,.. yeah, it's intersecting so reducing the diameter works or changing the original center sweep path/loop can help..

                            but... as is, if you want make it work, use Profile Twist - "Natural" (seems to allow for intersection).. (image attached)

                            natru 2.png

                            ..and... "Tangent to Adjacent Faces" also will allow the intersection in this case..

                            tangu 2.png34-38e.png34-38b.png

                            ..and furthermore,.. if I relax/reset the center curve (34 and 38 differences).. there are new overlapping/intersecting issues on the v1 and v2.. so, the center curve needs to be massaged to work cleanly for both.

                             

                            ..lastly,.. I'll add an example of making this more consistent.... create a Arc Chain (master/parent) for the drape,.. and then Convert the arc chain into a Spline (child).  (this is the way of the sweep/twist beast.. it's more consistent or likes doing it this way). arcconvert.png

                              • Re: Draping a coil
                                Bob Gooding

                                Thanks Paul,

                                 

                                     That is really useful to me on two counts. Firstly extending my knowledge of the twist functionality for a swept surface. I must play with this a bit more. But, more importantly, the idea of a Spline (child). This is a better way to control the overall shape of the drape but it also has lead me to believe that if I treat the path of the solid sweep the same way, I.E. a composite curve that includes the sweeps at each end of the draped coil, I will be able to do one solid sweep which will help when rebuilding after an edit.

                                 

                                     This one has really caught my imagination, I still think it is witchcraft how SWX knew how to jump the profile to later part of the path though

                                 

                                Thanks to everyone who contributed, Bob

                                  • Re: Draping a coil
                                    Paul Salvador

                                    Bob, glad it helps and I hope others as well,..  it is confusing seeing the sweep give so many different results and I always "hoped" sw corp would provide a better way to examine the overlap/intersection "and" ways or options for compressing/expanding along the chain (using either a set of arcs/lines, spline, style-spline, composite and convert to spline.... they all give slightly different results.

                                     

                                    btw,.. you mentioned the need to check total wire length.. you may have you own way but since the convert to spline came into this... a quick way to check is combining the whole chain of curves/edges into one spline... (image attached)

                                    length 1.png

                                • Re: Draping a coil
                                  Deepak Gupta

                                  Here is the result (file attached as well). On a close look there is a self-intersection in that zone.

                                   

                          • Re: Draping a coil
                            Kevin Chandler

                            Bob Gooding wrote:

                             

                            Hello Friends,

                             

                            I've had a successful iteration of this part which is a study to try and estimate how a coil of cable will drape or hang in my project. But, by trying to alter it to more accurately follow my real world sample, I have stumbled on a strange phenomenon.

                             

                            As you can see below, I have twisted a surface along a spline to create a coiled path to sweep along (Thank you for helix-helix @Paul Salvador)... At one of my lower control points where the curvature of the spline has brought the loops into a possible interference, the sweep has jumped a revolution of the path! What strange magic is this?

                             

                            This is not super critical with respect to my model but I did want to get rough idea of where to place the holster for the IEC plug and the upshot would be a nice model for our marketing team to use in the full product renderings. The attached model is unfinished and configured to be Draped, Hung and As Drawn, where i will ultimately lay it flat and straight to describe it to our suppliers.

                             

                            Before I set off in that direction, could you offer some constructive comments on this approach and maybe I could simplify the method? (hoping for an avalanche )

                             

                            Warm regards, Bob

                            I suspect the red arrow points to a self-intersection failure.

                            • Re: Draping a coil
                              Glenn Schroeder

                              If you're looking for other input, after creating the first Sweep you can use an existing edge instead of creating a new sketch coincident with the it.  I know it says "Sketch Profile" in the property manager, but it doesn't actually need to be a sketch.  That will save you some time.

                               

                              • Re: Draping a coil
                                Dave Bear

                                Awesome thread here Bob,

                                I am going to need to do this exact same process when I create the CB radio cord hanging from the roof console in my truck model. Thanks for doing my homework for me in this instance!

                                Seriously, thanks to all that got involved in this post.

                                 

                                Dave.