I tried the lisp but it told me the same thingcant extrude self intersecting curve. Saving and reopening the drawing later, will no longer indicate the unresolved. Then i start a 2d sketch on my 30 degree work plane, project the edge i want from the 3d sketch and offset it whatever i want my gap to be. How to extrude a selfintersecting or curves drawing into 3d. Net block insertion along closed polyline aug 3, 2011. I am trying to import coordinate points to design modeler to get a curve. To find intersection point of a selfintersecting bspline. Some dwg drawings may contain curves polylines with selfintersecting segments creating loops, or polylines containing duplicate vertices. I have created a text file which contains 5 columns. Slice the sweep in two halves, in order to create a selfintersecting compound. The figure shows the tubing curve intersecting the inflow curve in two.
Selfintersection detection and elimination in freeform. Ideally, the cad program exports a sphere and a cube without having the interior overlap highlighted in the picture below. Apr 14, 20 with autocad 2014 you now have the ability to use the fillet or chamfer commands on a polyline that is selfintersecting. Since the boundary curve is offset in a threedimensional 3d space, the local self intersection in the offset curve is addressed in a 2d space by approximately mapping the offset vectors in the. The software s affordability and ability to run on personal computers in the mid1990s allowed engineers to do their own drafting and analytic work to some extent. The 3d spline curve is selfintersecting solidworks forums.
With a part open, click intersection curve on the sketch toolbar, or tools sketch tools intersection curve. To find intersection point of a selfintersecting bspline curve. Catia is a worldclass 3d software that incorporates computeraided design cad, computeraided manufacturing cam, and computeraided. When the radius of a fillet is set to or when there is no angle set to a chamfer, these tools can be used to clean intersections by trimming or extending objects at their intersections. Question asked by samuel pinckney on oct 6, 2017 latest reply on oct 7. Cad forum fix problem of areas on selfintersecting. I would like to detect if a certain polyline is selfintersecting and if so i would like to compute those intersection points. Userwish 7 siemens nx 9 training wrap curve duration. This applies only to self intersecting faces, not two different faces of the same feature that intersect. I would like import this surface topography text file as 3d curve to designmodeler, but i get the following error. It is possible to build bad models using rhino tools for. May 20, 2009 in the properties dialog for curve, on the curve page, checkmark show frame.
If this message is ignored, the drawing dimensions may not update correctly. For the life of me, i cant figure out why so many ask. Fixing selfintersecting curves for extrusion i have been working on this project for awhile, trying to get it to extrude. Jan 27, 2011 nx hints and tips extrude with intersecting section curves in one feature siemens software. I understand why its self intersecting, but i have no choice, this is the curve shape i must work with, and i must use this surface to trim solids with. I cut a linear pattern of spacer grids with mixing vanes through a channel to study subchannel thermal hydraulics in modular pwrs. Nx hints and tips extrude with intersecting section curves. Ive tried region based and part based meshing, i believe. My question is how can we prove that the curve does in face self intersect, and, if possible, find the coordinates of a particular intersection point a general formula would be lovely, but it seems like a far shot. Autocad civil 3d illegal selfintersecting or nonclosed. I noticed that geometry size was very large which made me. Nx hints and tips extrude with intersecting section curves in one feature siemens software. Identifying selfintersection points in one parametric.
To open a 2d sketch, select the plane first then click intersection curve. Click 3d sketch tab draw panel intersection curve to create a 3d curve. I did have an issue with the symmetry plane that cuts the center of the car. Command locator crashing autocad if a custom ribbonsplitbutton is present main. With autocad 2014 you now have the ability to use the fillet or chamfer commands on a polyline that is. We often will xref our first floor plans onto our second floor plans and then create a rather involved pline to use as a. I do this sort of extrusion all the time closed polylines with. Sometimes a model can become damaged and the damaged areas can cause problems. Here is an older vb script from my library for selecting self intersecting curves and marking the intersection points. Mar 31, 2018 the computeraided design cad files and all associated content posted to this website are created, uploaded, managed and owned by third party users. How to find lines in a network that self intersects.
I cannot sweep or extrude a self intersecting curve. The model below is a good example of intersecting surfaces. Apr 05, 2016 i made a program that graphs a figure 8 using equations, and it outputs a single curve. Self intersecting curves curve data comprises lines, arcs, or splines. I have the option to change the bounds, so i can print out a half finished 8 or just a half of the 8, but i didnt make a maximumminimum value for the bounds, so theoretically i could make the curve draw over itself an infinite number of times. I cannot sweep or extrude a selfintersecting curve. Beginning in the 1980s, cad software reduced the need for draftsmen. Extrude option does not work in autocad 2010 software and shows the error message that cant sweep or extrude selfintersecting curves. Im getting this message sometimes when i try to extrude objects with lots of curves and arcs. Identifying selfintersection points in one parametric graph. So,i want to find the intersection point in order to trim. Cad forum fix problem of areas on selfintersecting curves in autocad 20. Any ideas what a self intersecting curve looks like. Can anyone please help me to find the intersection point of a selfintersecting bspline curve.
I often use svgimported beziers to create the geometry, and frequently i have problems with selfintersecting bezier curves. Finding selfintersections on a polar curve mathematics. Straight lines conic sections freeform parametric curves bsplines, nurbs curves of intersection between surfaces defined during model construction curve use in design. This applies only to selfintersecting faces, not two different faces of the same feature. A great new piece of functionality in the extrude tool allows the user to extrude selfintersecting curves. When using a cadsystem for designing geometric objects, youll find. The bottom pices are what i have broken it into and joined as polylines for extrusion. Some dwg drawings may contain curves polylines with selfintersecting segments creating loops, or polylines containing duplicate vertices superfluous repeating vertices or backing zigzag, self retracing segments or segment parts. I then exploded closed and opened a few of the separate curved elementsrejoined and for some reason autocad now sees it as extrudable so i am back to work. Oct 31, 20 autocad 20 selfintersecting curves for extrusion oct 31, 20.
Mike carter shares a trick he developed to deal with selfintersecting clip boundaries. I have the option to change the bounds, so i can print out a half finished 8 or just a half of the 8, but i. Use the curve to create shapes such as those used in consumer products, piping, and to control the shape of complex lofts. A great new piece of functionality in the extrude tool allows the user to extrude self intersecting curves. Intersections in cad when using a cad system for designing geometric objects, youll find inside the cad system extensive use of intersection algorithms to determine which parts of curves and surfaces describe the shells of the volume, and to establish the correct relation between points, curves and surfaces used in the description. Cad forum selfintersecting polylines and polylines with. Can anyone please help me to find the intersection point of a self intersecting bspline curve. Selfintersecting curves curve data comprises lines, arcs, or splines. Beginning in the 1980s, cad software reduced the need for draftsmen significantly, especially in small to midsized companies. I had a look at thelarge outer polyline and it appeared ok using the. I do this sort of extrusion all the time closed polylines with various geometry and usually have no trouble. In order to make sure that each pair t1, t2 corresponds to the same intersection, and that we have found them all, and that they are correct, we can plot the points together with the original curve. Autocad 2014 self intersecting polylines autocad tips. Any ideas what a selfintersecting curve looks like.
Autocad 3d self intersecting surface while sweeping. May 01, 2012 when i try to extrude this closed polyline yes it is closed i get the message cannot sweep or extrude a self intersecting curve. Curves in modeling curves produced in modeling systems. Nx hints and tips extrude with intersecting section. Tagged withboolean, cad, curves, design visionaries, design viz. In selection info, check show frame in the curve section. Modeling uncertainty the bodies or surfaces have low. This is a great way to create ribs or similar features without having to extrude lines separately.
Split and trim curves and surfaces linkedin learning. I made a program that graphs a figure 8 using equations, and it outputs a single curve. For instance, if you trim a surface with a selfintersecting curve, rhino will let you do it, but the result will be a poorly defined model that causes. Question asked by alan thomason on jul 24, 2014 latest reply on jul 27, 2014 by alan thomason. To open a 2d sketch, select the plane first then click intersection. As you draw your curve, it places a polyline between the points. I am trying to create a cad drawing for the construction of paddle pop sticks. Geometry errors self intersecting surfaces a surface that folds onto itself is a self intersecting surface. A 3d sketch opens because you clicked before selecting a plane. An open selfintersection is a selfintersection that occurs inside a. Caddoctor for nx enables both the nissan and the supplier to validate and secure the quality of all. This applies only to selfintersecting faces, not two different faces of the same feature that intersect. The figure shows the tubing curve intersecting the inflow curve in two places. For the life of me, i cant figure out why so many ask questions without providing enough information.
Remove the intersection by adding a sketch point at curve intersections or by changing nonprofile geometry to construction geometry. To open a 3d sketch, click intersection curve first then select the plane. Pedit command edit a vertex abdusing the next option to walk arond. Geometry and topology error reference repair and construction. All crossing intersections and selfintersecting curves are rejected. Since the boundary curve is offset in a threedimensional 3d space, the local selfintersection in the offset curve is addressed in a 2d space by approximately mapping the offset vectors in the. Because you selected object and it didnt work im betting a selfintersecting curve. Selfintersecting polylines and polylines with duplicate vertices. The pdq np is a plugin for nx that provides instant cad model checking, healing, and certification. Hi i keep getting the above error but the curve does not intersect. The top drawing of the shape is when i created it, still as lines and arcs. My question is how can we prove that the curve does in face selfintersect, and, if possible, find the coordinates of a. Most of the problems i can spot and correct in inkscape after. Inventor doesnt allow it but other software allows you to change the sketch of the bend during creation, but with inventor you need to draw it before hand.
A shell selfintersection is an intersection between different surfaces in the shell. We often will xref our first floor plans onto our second floor plans and then create a rather involved pline to use as a clipping boundary for the xclip command to mask off parts of the first floor xref that we dont want to be visible on the second floor. I got it to work for a few models earlier, but once i added a fin to the solidworks model and tried to run it again, it started giving me the. This prevents automated programs from posting comments. The way to identify these issues is through going to repairidentify self intersecting surfaces. Aug 29, 2019 when performing a series of surface commands in nx 11. Can produce self intersecting curves easy to determine whether a given point lies on the line set. To use the sketched curve to extrude a feature, the sketch that opens must be a 2d sketch. I have a rather strong feeling that this is really easy but im not getting how for some reason. Selfintersecting loop found in this profile prevents dimension values in inventor drawing products and versions covered inventor 2018, inventor 2019, inventor lt 2018, inventor lt 2019, inventor.
The result is a surface thats self intersecting that i cant trim other solids with. Each cad and any associated text, image or data is in no way sponsored by or affiliated with any company, organization or realworld item, product, or good it may purport to portray. Tip of the day 32 self intersecting surfaces simplify3d. Such polylines with nonstandard geometry may cause different problems when processing. I replaced your curve with a smooth one and performed the sweep with no problems. Jan 26, 2014 because you selected object and it didnt work im betting a self intersecting curve. Instead of having to painstakingly tweak a curve with thousands of small segments, you position a few control. Discussions about mcneel related software products rhino3d, grasshopper, flamingo, bongo, brazil, neon. It is possible to build bad models using rhino tools.
For instance, if you trim a surface with a self intersecting curve, rhino will let you do it, but the result will be a poorly defined model that causes problems later. Faces, surfaces, or the entire part body 2d sketch curves work planes on the ribbon, click 3d model tab sketch panel create 3d sketch. As previously pointed out, the selfintersection is to be expected. Fix problem of areas on selfintersecting curves in. The first example of global selfintersection elimination is illustrated in fig.
Sheet metal self intersecting flanges error autodesk. Intersecting curve an overview sciencedirect topics. The curve where the surfaces meet will be an edge in the cadmodel to be found by intersecting the surfaces. Cannot sweep or extrude a selfintersecting curve autocad 3d. The problem is that the obtained bspline curve is self intersecting. The computeraided design cad files and all associated content posted to this website are created, uploaded, managed and owned by third party users. Figure 44 shows a tubing performance curve intersecting a well deliverability inflow curve inflow performance curveipr. Region command autocad 2020 autodesk knowledge network. Surfaces must be continuous and smooth without changing direction. Fix problem of areas on selfintersecting curves in autocad 20 the command area in autocad 20 old, no more referenced from menu does not report proper area of polylines containing intersecting. I check the mesh in rhino and rhino reports its fine. Be careful with file tolerance, it also finds parts of the same curve folded back on itself that are nearer than file tolerance but dont necessarily cross mitch. I often use svgimported beziers to create the geometry, and frequently i have problems with self intersecting bezier curves. Geometry errors selfintersecting surfaces a surface that folds onto itself is a selfintersecting surface.
Im not at all suggesting that things should be done this way, since it will be decidedly slow, and the undocumented findintersections function is apparently a little unreliable, but i thought the following. Model complex 3d architectural geometry with rhinoceros. How to extrude a selfintersecting or curves drawing into. I even tried to slice a model from ultibots the micro extruder body created in alibre design, and their stl had the same issues. Autocad 3d self intersecting surface while sweeping dec 12, 2011. When i try to extrude this closed polyline yes it is closed i get the message cannot sweep or extrude a selfintersecting curve. Besides drawing a geometric model with the cad tools built into comsol multiphysics, an alternative is to create it with a specialized cad software application and save it to a fileone that the.
Free product trials 3d cad software civil engineering drafting. Curve representation all forms of geometric modeling require the ability to define curves. Processing these files through netfabbs mircosoft cloud service doesnt remove these self intersecting surfaces. I have been working on this project for awhile, trying to get it to extrude. Geometry errors selfintersecting surfaces a surface that folds onto itself is a. I cut a linear pattern of spacer grids with mixing vanes through a channel to. I got it to work for a few models earlier, but once i added a fin to the solidworks model and tried to run it again, it started giving me the same self intersecting geometry errors despite having no pierced faces.
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