Using Pro/ENGINEER AutoRound Feature

AutoRound is a feature in Pro/ENGINEER Wildfire 4.0 that intelligently rounds all the edges of a part. This feature enables you to create rounds of a constant radius on a solid or a quilt of a Pro/ENGINEER part or assembly.

In this technical tip we will create the AutoRound Feature and look at how to convert it into rounds which can later be individually modified.

1. Click >Insert >Auto Round from the Pro/ENGINEER menu. Adjust the radii values for the convex and concave edges (Figure 1). Also, if needed, exclude certain edges that you would not like to have rounded using this method. Complete the feature.

2. Select the AutoRound feature from the Model Tree and right-click in order to Convert to Group. This operation (Figure 2) will convert the AutoRound feature in a group of individual round features for each of the edges that were previously selected.

3. Select the just created group and right-click to Ungroup. You can adjust/modify/delete each of the round sets and/or radii values.

Using Mechanism Design Spring & Damper Parameters

Another great enhancement that can help you in setting proper Spring and Damper properties has been introduced in the Mechanism Design module of Pro/ENGINEER Wildfire 4.0. The properties of the Spring and Damper idealizations can be parameterized and added to Pro/ENGINEER relations and Family Tables.

In this technical tip, we will take a look at how to make use of this new functionality in order to find the proper spring stiffness required to sustain a certain reaction load. We will combine the functionality from Mechanism Design and Behavioral Modeling modules to attain our optimum solution.

1. Define a new Pro/ENGINEER parameter using >Tools >Parameters (note that in Pro/ENGINEER Wildfire 4.0 you can directly define this parameter in Mechanism Design module) as seen in Figure 3.

2. Assign this parameter to the spring stiffness (Spring & Damper idealizations are Pro/ENGINEER Wildfire 4.0 features) by creating a simple relation (Figure 4). Create a Mechanism Design measure to evaluate the reaction load developing in the spring.

3. Select >Applications >Standard and define a new Optimization Study via >Analysis >Optimization/Feasibility. Next, set the goal, design limits and parameters (Figure 5). The result will provide you with the spring stiffness able to sustain the reaction load.

Controlling Element Size in Pro/ENGINEER Mechanica

Another set of improvements has been brought to the Pro/ENGINEER Mechanica AutoGEM settings tool. If you use Pro/ENGINEER Wildfire 4.0 you can now control the maximum size of elements, improve the number of elements in areas of local curvature, and exclude elements where singularities may occur.

You can control the maximum size of elements in certain areas of the model or for an entire component (or, series of components). This option, Maximum Element Size can be customized in the AutoGEM Control dialog box, which can be accessed via >AutoGEM >Control menu from within Pro/ENGINEER Mechanica.

With the new curvature-based mesh control (Edge Length by Curvature), you can now add additional elements only where the geometry of the model has curvature (thus, elements are sized by the local curvature). This option comes in handy since default values for the AutoGEM limits sometimes tend to be overly aggressive in minimizing the number of elements in mesh.

You can now exclude elements in areas of singularities using the Isolate for Exclusion AutoGEM control. By ignoring these singularities you can now save analysis time and get high-quality results.

All these options are presented in Figure 6, comparing, for the same geometry, four different scenarios of P-element generated meshes.