In this tutorial, we will show how to create surfaces from a complex mesh model by using Surface from Mesh option. The original mesh model is shown in the following picture.
mesh model We will create 12 surfaces from the mesh model. They are shown in the following 2 pictures. From the pictures, you can see the surfaces boundary lines extending along the natural mesh feature line. We will show how to select the elements by Propagation method for reasonable feature line boudanry capturing, we also will show some details for better surface generation.
surface
surface
Create surface s1. First of all, click bottom toolbar icon
to set the element displaying mode as Hide Elem. This mode enable users select the element easily. Then click бо Geometry->Surface->Fit from pnts/mesh ' or click the left icon
, check the checkbox Prop and set the Ang as 10, select element as shown as the highlighted elements in the following picture.
mesh selection These elements capture the fillet feature line on both side of boundary, also the boundary line is very similar to a rectangle since there are 4 right angles (tagged by green circle in the picture), therefore we check the checkbox Untrimmed boundary in the dialog and create the surface as untrimmed surface ( surface boundary is iso-line).
sub-mesh Untrimmed surface has more advantages of matching with neighbor surface on the boundary line to G0/G1 continuity in math than trimmed surface since untrimmed surface boundary line is iso-line while trimmed surface boundary line is not iso-line.
untrimmed surface If we do not check the checkbox Untrimmed boundary , the surface will generate a trimmed surface as shown in the following picture. However, we prefer to use the untrimmed surface.
trimmed surface
After you have gotten a satisfactory surface , such as the precision has been smaller than 0.01, you click button Apply to add the surface into database, then click the checkbox Mesh again for another new surface generation .
Continue to create surface S2 to S8 by using the same element selection method in step1. When you select elements, pay attention to keep the surface boundary smooth enough for being matched with new surface S9 later.
surface boundary
Continue to create surface S9. Select all the highlighted elements shown in the following picture by setting Prop Ang = 10 .
surface
Continue to create surface S9. Select all the highlighted elements shown in the following picture by setting Prop Ang = 10 .
selected mesh Make sure that you have selected all the neccessory elements. In the following picture, there is one triangle element (in green circle)lost in the selection. This lost element will result in a hole in the surface, or sometimes if this element happens on boundary position, the surface may can not be created successfully due to self-interstionc boundary line happening there.
improve mesh selection Continue to select all the neccessory elements for surface S9, and make sure the surface boundary has been matched the original surface's boundary very well.
better selected mesh Set Max tol = 0.01, uncheck Untrimmed boundary . (we uncheck this button since we can accept trimmed surface here). Click button Preview for base surface and click button Fit for advanced surface to create surface S9.
surface
create surface s10 by setting Prop Ang = 10 for element selection , unchecked Untrimmed boundary and Max tol= 0.01.
surface
Continue to create surface s11 and s12. In order to get fine boundary line, we create both of them as untrimmed surface.
surface Finally, we have created all surfaces.
final surface