G2 constraint Curve mesh problem

[TinkyWinky]

Hi !

Iam trying to do some curve meshs which are g2 to each other.

when i select g2 contiunity with a surface adjacent to a primary curve of the mesh it get the "Internal error Memory access violation" (Speicherzugriffsverletzung) if i select G1 i dont get this, but all curves of the mesh are G2 to the nearby surface, so why this? It doesnt even work if i select this G2 as the only constraint to nearby surfaces (other sides are G0)

I attached the file with the "broken" curve mesh 99

Might there be something wrong with my geometry??

the first cross curve should also be g2 with the curve mesh i want to create (see file)


thx in advance

 

[TinkyWinky]

I found this in the nx log file:

&MACRO DIALOG_BEGIN "Through Curve Mesh" 0 ! DA2
&MACRO BEG_ITEM 393216 (1 BOOL 0) = 0 ! Primary Curves
&MACRO BEG_ITEM 1179648 (0 BOOL 0) = 0 !
&MACRO BEG_ITEM 3932160 (1 BOOL 0) = 0 ! Cross Curves
&MACRO BEG_ITEM 4718592 (0 BOOL 0) = 0 !
&MACRO BEG_ITEM 7405568 (1 BOOL 0) = 0 ! Apply to All
&MACRO BEG_ITEM 7667712 (1 OPTM 0) = 0 ! G0 (Position)
&MACRO BEG_ITEM 7864320 (1 BOOL 0) = 0 ! Face
&MACRO BEG_ITEM 8585216 (1 OPTM 0) = 1 ! G1 (Tangent)
&MACRO BEG_ITEM 8781824 (1 BOOL 0) = 0 ! Face
&MACRO BEG_ITEM 9502720 (1 OPTM 0) = 2 ! G2 (Curvature)
&MACRO BEG_ITEM 9699328 (1 BOOL 0) = 0 ! Face
&MACRO BEG_ITEM 10420224 (1 OPTM 0) = 0 ! G0 (Position)
&MACRO BEG_ITEM 10616832 (1 BOOL 0) = 0 ! Face
&MACRO BEG_ITEM 11599872 (1 BOOL 0) = 0 ! Spine
&MACRO BEG_ITEM 12517376 (1 OPTM 0) = 0 ! Both
&MACRO BEG_ITEM 12713984 (1 OPTM 0) = 0 ! Normal
&MACRO BEG_ITEM 12910592 (1 BOOL 0) = 0 ! Primary Template
&MACRO BEG_ITEM 13500416 (1 BOOL 0) = 0 ! Cross Template
&MACRO BEG_ITEM 14483456 (1 BTAB 0) = 1 !
&MACRO BEG_ITEM 14745600 (1 OPTM 0) = 0 ! None
&MACRO BEG_ITEM 14942208 (1 INTE 0) = 3 ! Degree
&MACRO BEG_ITEM 15138816 (1 OPTM 0) = 0 ! Cubic
&MACRO BEG_ITEM 15335424 (1 INTE 0) = 7 ! Maximum Degree
&MACRO BEG_ITEM 15532032 (1 INTE 0) = 1 ! Maximum Segments
&MACRO BEG_ITEM 15728640 (1 INTE 0) = 3 ! Degree
&MACRO BEG_ITEM 16187392 (1 OPTM 0) = 0 ! None
&MACRO BEG_ITEM 16384000 (1 INTE 0) = 3 ! Degree
&MACRO BEG_ITEM 16580608 (1 OPTM 0) = 0 ! Cubic
&MACRO BEG_ITEM 16777216 (1 INTE 0) = 7 ! Maximum Degree
&MACRO BEG_ITEM 16973824 (1 INTE 0) = 1 ! Maximum Segments
&MACRO BEG_ITEM 17170432 (1 INTE 0) = 3 ! Degree
&MACRO BEG_ITEM 17825792 (1 REAL 0) = 0.0200000000000000 ! Intersection
&MACRO BEG_ITEM 18022400 (1 REAL 0) = 0.0010000000000000 ! G0 (Position)
&MACRO BEG_ITEM 18219008 (1 REAL 0) = 0.1000000000000000 ! G1 (Tangent)
&MACRO BEG_ITEM 18415616 (0 REAL 0) = 0.5000000000000000 ! G2 (Curvature)
&MACRO BEG_ITEM 19202050 (1 BOOL 0) = 1 ! Preview
&MACRO ASK_ITEM 393216 (1 BOOL 0) = 0 ! Primary Curves
&MACRO ASK_ITEM 393216 (1 BOOL 0) = 1 ! Primary Curves
&MACRO EVENT FOCUS_IN 0 0, 8585216, 1, 0, 0! G1 (Tangent)
&MACRO ASK_ITEM 8585216 (1 OPTM 0) = 1 ! G1 (Tangent)
&MACRO EVENT ACTIVATE 0 0, 8585216, 2, 0, 0! G2 (Curvature)
&MACRO ASK_ITEM 8585216 (1 OPTM 0) = 2 ! G2 (Curvature)
&MACRO ASK_ITEM 8585216 (1 OPTM 0) = 2 ! G2 (Curvature)
&MACRO ASK_ITEM 8585216 (1 OPTM 0) = 2 ! G2 (Curvature)
&MACRO ASK_ITEM 393216 (1 BOOL 0) = 1 ! Primary Curves
&MACRO ASK_ITEM 393216 (1 BOOL 0) = 0 ! Primary Curves
*** EXCEPTION: O/S ERROR: signal 11 in line 1686 of O:\ugnx603\ip6\src\syss\error\ind\error.cxx at Thu Aug 20 14:04:11 2009 W. Europe Daylight Time
+++ General Fault Exception
[ 1] 000029D8AEF0 (libpart)
[ 2] 000029D8C40F (libpart)
[ 3] 0000251F285C (libcmod)
[ 4] 00001D889069 (libuimodl)
[ 5] 00001D888345 (libuimodl)
[ 6] 00001D88697A (libuimodl)
[ 7] 000039DFD752 (libuifw)
[ 8] 000039E14B94 (libuifw)
[ 9] 00001D885E69 (libuimodl)
[10] 000039E54A10 (libuifw)
[11] 000039E756E7 (libuifw)
[12] 000039E729A6 (libuifw)
[13] 0000209DB9DE (libugui)
[14] 0000209DC225 (libugui)
[15] 0000209DC648 (libugui)
[16] 0000209DCD4C (libugui)
[17] 000021B6B745 (windowsui)
[18] 000021B4DAFD (windowsui)
[19] 000021B6E89E (windowsui)
[20] 00007837CF2C (MFC80U)
[21] 00007837D190 (MFC80U)
[22] 00007833FDB5 (MFC80U)
[23] 00007833FCF0 (MFC80U)
[24] 00007835CCE9 (MFC80U)
[25] 00007833FB73 (MFC80U)
[26] 00007833FC58 (MFC80U)
[27] 00007833ECC9 (MFC80U)
[28] 00007833DFE0 (MFC80U)
[29] 00007833DF4C (MFC80U)
[30] 00007833C1A0 (MFC80U)
[31] 00007833C561 (MFC80U)
[32] 000078339653 (MFC80U)
[33] 000077C43ABC (USER32)
[34] 000077C4337A (USER32)
[35] 000077C7B359 (USER32)
[36] 000077C79A07 (USER32)
[37] 000077C7AE0C (USER32)
[38] 000077C43ABC (USER32)
[39] 000077C435D1 (USER32)
[40] 000077C436FB (USER32)
[41] 00007833D1C8 (MFC80U)
[42] 00007833DF64 (MFC80U)
[43] 00007833C1A0 (MFC80U)
[44] 00007833C561 (MFC80U)
[45] 000078339653 (MFC80U)
[46] 000077C43ABC (USER32)
[47] 000077C4337A (USER32)
[48] 000077C4341B (USER32)
[49] 000077CAAF90 (USER32)
[50] 000077CAA90B (USER32)
[51] 000077CA40E0 (USER32)
[52] 000077CA5541 (USER32)
[53] 000077C43ABC (USER32)
[54] 000077C435D1 (USER32)
[55] 000077C436FB (USER32)
[56] 00007833D1C8 (MFC80U)
[57] 00007833DF64 (MFC80U)
[58] 00007833C1A0 (MFC80U)
[59] 00007833C561 (MFC80U)
[60] 000078339653 (MFC80U)
[61] 000077C43ABC (USER32)
[62] 000077C43F5C (USER32)
[63] 000078390F32 (MFC80U)
[64] 000021BA5A10 (windowsui)
[65] 000021BA7B97 (windowsui)
[66] 000021BA8133 (windowsui)
[67] 000020A1B7E0 (libugui)
[68] 0000209F6E1E (libugui)
[69] 0000209F6EF6 (libugui)
[70] 0000209F710C (libugui)
[71] 000020AA8A4F (libugui)
[72] 000020AA92E8 (libugui)
[73] 000039E573B8 (libuifw)
[74] 000020B6951A (libugui)
[75] 000038974741 (libmodlint)
[76] 00002524EE75 (libcmod)
[77] 000020519270 (libsyss)
[78] 0000205194CC (libsyss)
[79] 00002524C1F0 (libcmod)
[80] 00002524E4B4 (libcmod)
[81] 000038A8A160 (libmodlint)
[82] 000038A8D824 (libmodlint)
[83] 000038A8FE27 (libmodlint)
[84] 000020B69BE3 (libugui)
[85] 000020B69E71 (libugui)
[86] 000020A1B4AD (libugui)
[87] 000021BA7B68 (windowsui)
[88] 000021BA8133 (windowsui)
[89] 000020A1B7E0 (libugui)
[90] 000020BBAD87 (libugui)
[91] 000020B6A169 (libugui)
[92] 00002025A4DC (libuginitint)
[93] 0000202550CD (libuginitint)
[94] 000140003521 (ugraf)
[95] 00014000201A (ugraf)
[96] 000140006921 (ugraf)
[97] 000077D596AC (kernel32)
>>>> O/S ERROR: signal 11 caught in file "O:\ugnx603\ip6\src\uifw\no\ind\ModlUtilsUI_FreeFormPreview.cxx" at line number 1041
&MACRO DIALOG_BEGIN "Persistent Dialog" 129015 ! Persistent
&MACRO DIALOG_PERSISTENT_END 129015
&MACRO ASK_ITEM 8781824 (1 BOOL 0) = 0 ! Face
&MACRO ASK_ITEM 8781824 (1 BOOL 0) = 1 ! Face
&MACRO FOCUS CHANGE OUT 1
&MACRO FOCUS CHANGE OUT 1
&MACRO MENU, 0, UG_HELP_SYSTEM_LOG UG_GATEWAY_MAIN_MENUBAR !
&MACRO MENU, 0, UG_LWIN_FILE_EXIT ListingWindowMenuBar !
&MACRO FOCUS CHANGE IN 1
&MACRO FOCUS CHANGE OUT 1

 

[JohnRBaker]

The single 11 error (Memory Access Violation) is generally an indication of a problem with the software and not the model. I took your file and recreated the last couple of surfaces using NX 6.0.4.3 and it worked fine. I've attached the model to this post and you should be able to open it and perhaps even continue to work, but you may still encounter the problem but it does appear that when the next MR is released (NX 6.0.4.3) which will be soon, that this problem may no longer be there since I didn't get the error.

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.

 

[TinkyWinky]

Thx for your help John,

strangely enough i was able to fix this by checking the intersecting curves with the upper mesh surface on which i aligned the g2 continuity.
I changed them from cubic to 5th grade and i created some of those curves in the sketches (maybe not accurate enough for the program?),so i deleted those being created within the sketch and instead i created them in 3d space by intersecting with the corresponding datum plane.

After this the surface could be created with g2 ?



NX6

 

[hudson888]

The way the system works for the time being at least is that you'll generally find studio splines in 3D space happier bedfellows with surface creation than you will splines built inside sketches. A number of associativity functions simply exist as supported better by the former than the latter.

Best Regards

Hudson

www.jamb.com.au

Nil Desperandum illegitimi non carborundum

 

[Xwheelguy]

If splines are created in Sketcher, how are you assigning G2 continuity to them within the Sketch? The curves have to be within the G2 tolerance in order for the surface to be successfully created with G2 continuity. As hudson kindly pointed out, this is much easier to achieve with Studio Splines...and yes, try to always use 5 degree curves when you're wanting G2 continuity between the surfaces.

Surfaces always reflect the quality of the curves being used. If you use poor curve networks or the wrong settings (spline degree or segmentation), then your surfaces are probably not going to look very good and might be quite difficult to deal with the continuities.

Tim Flater
Senior Designer
Enkei America, Inc.

http://www.enkei.com

Some people are like slinkies....they don't really have a purpose, but they still bring a smile to your face when you push them down the stairs.

 

[hudson888]

Yep! If you use at least degree 3 for G1, degree 5 for G2 or degree 7 for G3 continuity then you can create a single segment curve with a studio spline. In all other cases the system may/will create multi segment curves. Simplicity being the essence of an elegant solution fewer segments are usually preferred.

Best Regards

Hudson

www.jamb.com.au

Nil Desperandum illegitimi non carborundum