Creating Trajectory Ribs

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Creating Trajectory Ribs Theory

Like the traditional Profile Rib, Trajectory Ribs are typically used to strengthen parts; however, with a Trajectory Rib, you sketch the rib centerline from a top view, instead of sketching the rib from a side view. You can select an existing sketch or sketch internal to the Trajectory Rib.

The system can add material above or below the sketch, but with a Trajectory Rib the thickness is always applied symmetric about the sketch. You can also choose to add draft or rounds as part of the Trajectory Rib feature.

The sketch used for a Trajectory Rib has special abilities:

- The rib will self-extend to find solid material. Therefore, you do not have to extend the sketch and align it to the part. If sketched beyond the model, the rib will automatically trim itself to the model boundaries.

  • In the case of a model with complex wall geometry, it is best to allow the system to self-extend the rib to the model.

- The rib sketch can intersect itself. This enables quick and easy sketching to achieve the desired rib.

- The rib sketch can pass through existing features, such as screw boss geometry. The systems simply ignores the existing solid geometry, and continues the rib in the next free space.

- The rib sketch can have multiple open loops, unlike sketches for most other solid features. This enables you to sketch multiple unconnected ribs in the same feature.

The Trajectory Rib has several options:

  • You can add Draft. Draft is added such that the exposed end of the rib maintains its width, and you can specify the angle that tapers outward and towards the base of the model.
  • You can add rounds on the exposed edges of the rib. With this option you can round the top of the rib using a two-tangent round. The size of the two-tangent round is controlled by the width of the rib, similar to creating a full round. You can also create the rounds by specifying radius values manually.
  • You can add rounds on the internal edges of the rib. With this option you can round the bottom of the rib using a radius value that is equal to the top (exposed edges), or by specifying radius values manually.

Once a Trajectory Rib is created, there are some additional options:

  • You can right-click the rib and select Externalize Rounds. This separates the rounds from the rib feature, and creates a round feature in the model tree. The rounds can then be further customized.
  • If you did not add rounds within the rib feature, the internal and exposed edges of the rib are made available for quick selection by querying to an intent edge set.

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