Auto Midsurface Tool

closed solid

Select a single surface of the solid geometry and click extract. The enclosed volume the selected surface belongs to is automatically determined, and the midsurface is extracted from it.

incomplete solid

Enable additional options for selecting and orienting the surfaces defining the body to extract.

When normals are consistent, color display normals colors the outer surfaces of the model red or blue, but never a mixture of both. For most models, normals are automatically oriented consistently.

fix normals

Automatically fix the normals of all the surfaces in the selection.

reverse normals

Reset your surface selection and select the surfaces for which normals need to be adjusted if surface normals are inconsistent.

offset + planes + sweeps

Identify the places where a piece of plane or a piece of a sweep surface can be used as a middle surface. A middle surface is constructed at the remaining places in the model, for example the places where planar or sweep surface pieces cannot be used as a middle surface, by the same algorithm as in offset via the offset of the model's sides.

Figure 1.

offset + planes

Identify the places in the model where a piece of plane can be used as a middle surface. At the remaining places in the model, for example the places where planar pieces cannot be used as a middle surface, the same algorithm as in offset is used to construct the middle surface via the offset of the model's sides.

Figure 2.

offset

Create pieces of the middle surface by offsetting the model's side surfaces towards the middle. This is the traditional approach for midsurfacing in HyperWorks.

Figure 3.

skin offset

Method description: The "skin offset" method automatically detects the two largest faces on the model, detects the thickness, and then creates the middle surface by offseting one of the faces towards the other one by half of thickness. This is the quickest method for creating a midsurface. However, it is not applicable to many models.

Assumptions:

• There are smooth transitions along the faces. Sometimes, certain non-smooth transitions may be handled by increasing the default geometry feature angle.
• There are no smooth transitions at edges/holes from one face to another one, the transitions should be sharp enough.
• No ribs are present. There should only be one face(plate) in the input.
• No variations in thickness are taken into account.

The typical models where "skin offset" can be successfully applied are metal stamped parts.

Figure 4.

align steps

Align midsurfaces.

step jumps

Produce steps between the various midsurfaces as in the original model.

Figure 5. Valid Steps. Steps are in Front of a Single Surface

Figure 6. Invalid Steps. Steps are in front of multiple surfaces.

auto mid position

Create a midsurface parallel to the largest side of the volume. This midsurface includes "offset" data to represent the changes in distance between the midsurface and the smaller faces at each "step".

Figure 7. . The midsurface (with orange nodes) is parallel to the larger face of the solid plate.

user mid position

define the offset of the midsurface, using a value from 0 to 1, in order to specify the offset from the largest side of the volume.

When extracting a new midsurface, the midsurface is generated using the collapsed lines that were automatically found during the initial midsurface extraction and the lines that you manually collapsed.

If allow rerun is disabled or the allow rerun switch is set to no rerun or prepare for rerun, then the lines that you manually collapsed will not be used when a new midsurface is extracted.

If use base surfaces is disabled, new midsurfaces will not be generated at the specified distance from the selected base surfaces. The setup of the base surfaces that you modified will be retained for future use as long as you do not delete them.

thickness bounds

Specify a minimum and maximum thickness of the plates in the part.

Middle surfaces are only created for plates with a thickness that falls into the specified range. Thickness bounds can improve the robustness of the results and speed up middle surface creation; however, you must be sure that you do not cut off some plates by selecting thickness limits that are too narrow.

no thickness bounds

Specify a max thickness ratio for midsurface extraction.

This is the highest acceptable ratio of the thickest plate's thickness to that of the thinnest plate. Plates whose thickness is greater than this value multiplied by the thinnest plate's thickness is ignored. Using too small of a value can cause incorrect midsurface extraction. However, larger ratios take more time to process.

Figure 8.

Since in many cases the fillet is not an exact cylinder and has a variable curvature, or the fillet cross-section is not orthogonal to the fillet axes, in reality the length on the curve at the fillet is taken and R is recalculated from this length as if it were an arc of a circle.

Clear this checkbox to use the global cleanup tol specified in the Options panel for stitching. This method is recommended when an extensive manual edit of the auto midsurfacing result is expected, because stitching comparatively distant midsurfaces may misrepresent the geometry of the model and affect following operations on geometry.

extract by component

If each part is contained in its own component, extract the midsurface of one component at a time.

cross components

If your model contains a single part organized in multiple components.

result in Middle Surface comp

Organize midsurfaces in the Middle Surface component (Recommended).

result in current comp

Organizes midsurfaces in the current component.

sorted results

Perform midsurface sorting immediately after extraction.

<~[o]riginal name> comp

Create new components by removing the first letter of the original component name and replacing it with a ~ and sorts the midsurfaces accordingly. For example, my_comp -> ~y_comp.

<Midsurface #nn> comp

Create components with the name Midsurface #, where # increases for each component that exists for the input surfaces/solids.

original comp

Organize the midsurfaces into their parent surface/solid components.

<original name~> comp

Create components using the original component name and adds ~ at the end.

<original nameN> comp

Create new components by incrementing the name of the original.