Navigating Pro/ENGINEER: Three Things You Didn’t Know

How to use Mathcad with Pro/ENGINEER Wildfire 3.0

Mathcad 13 complements the existing CAD/CAE capabilities of Pro/ENGINEER Wildfire 3.0. This technical tip provides an introduction to this integration and expands on some of the most important characteristics of this process.

Part or assembly parameters and dimensions can be associated to Mathcad worksheets with the help of Pro/ENGINEER Analysis features. Important values computed in Mathcad can be mapped back in Pro/ENGINEER for different parameters and dimensions to easily drive the CAD model without any loss of information.

The operation of mapping parameters and dimensions is accomplished by tagging the math regions of the Mathcad assignment variables. The most important characteristic of this operation is to ensure that Pro/ENGINEER parameters or dimensions and Mathcad variables have same unit type. In order to map a Mathcad unit that does not exist in Pro/ENGINEER, create a custom unit in Pro/ENGINEER to match the unit of the Mathcad variable.

Let’s consider the quick return mechanism example shown in Figure 1. The goal is to evaluate the angular motion of the slotted link using the dimensions of the model (length and angle) and angular motion of the crank at a specific instant. We want to identify the variation of this angular motion as the mechanism changes positions.

• Prepare the input using Pro/ENGINEER functionality as seen in Figure 2. You can define parameters (using relations, or different Measure analysis features) and establish the dimensions to be inputted into the Mathcad worksheet. Parameters (such as VEL_AB, etc in this example) were created without units. Appropriate units will be added in the worksheet using Mathcad functionality.
  
  
• Tag the math regions of the Mathcad assignment variables with proe2mc. (Figure 3). When you tag a math region as proe2mc, the Mathcad variable receives the value of the Pro/ENGINEER parameter or dimension as input. In order for Mathcad results variables to be available for computation in Pro/ENGINEER, you must tag the math regions as mc2proe as seen in Figure 4.
  
  
• From Pro/ENGINEER menu select > Analysis > Mathcad Analysis (or > Insert > Model Datum > Analysis). This operation will launch the Mathcad Analysis feature definition window as seen in Figure 5. Load the Mathcad worksheet, and specify the input and output by mapping it accordingly to the Mathcad variables. Once completed click Compute from the same definition window. Close the definition window.
  
  
• Mathcad Analysis feature output parameters can be specified and used either in Pro/ENGINEER relations, to further drive the CAD model, or simply called out in 3D notes for quick visual inspection. Any geometrical/parameter changes and proper model regeneration will be parametrically reflected in the Mathcad Analysis feature output parameters. (Figure 6)

This example can also be combined with Pro/ENGINEER Mechanism Dynamics functionality (e.g., evaluating the input angular motion at certain instant using the Motion Analysis feature), and so increases the advantage of using different Pro/ENGINEER modules for the same model without any loss of information or data.

How to use the right mouse button to accomplish simple tasks in Pro/ENGINEER Wildfire 2.0 and beyond

The process of creating an Extrude feature can be easily accomplished without the use of the dashboard in Pro/ENGINEER Wildfire 2.0 and 3.0.

• Select the Extrude button from the Pro/ENGINEER toolchest, or from Pro/ENGINEER main menu > Insert > Extrude.
  
  
• Without using the dashboard, click right mouse button (as shown in Figure 7) and select Define Internal Sketch. Specify references and complete your sketch.
  
  
• Define depth and value (Blind, Symmetric, etc).
  
  
• Specify if the extrude operation should be completed as Surface, Remove Material, etc. Choose direction and complete feature.

These right-mouse-button shortcuts can be used in Pro/ENGINEER Wildfire 3.0 (with the implementation of component placement dashboard) for assembling components.

• Click Add component to the assembly button from the Pro/ENGINEER toolchest, or from Pro/ENGINEER main menu > Insert > Component > Assemble, and retrieve a Pro/ENGINEER model for assembling.
  
  
• Without using the dashboard, click right mouse button (as shown in Figure 8) and either Move (for better positioning) or constrain component by default (or Fix it).
  
  
• If you wish to specify a certain location, use the Select component item and Select assembly item. You can add additional assembly constraints if needed. Complete the placement.
  
  
• In Wildfire 3.0, you can save this placement as an Interface.

How to model with motion skeletons and assigned mass properties in Pro/ENGINEER Mechanism Dynamics

Pro/ENGINEER Wildfire 3.0 parts created from motion skeleton bodies are, by default, without any solid geometry. Therefore, no mass properties can be evaluated. This is critical when about to analyze the dynamics of a mechanism assembly. The following can be used in this kind of situation or when about to create a light version of the model for easy data manipulation. You can also use this method if you wish to send a simplified model — that contains 3D solid proprietary data — to another enduser. All this can be done without affecting Pro/ENGINEER Mechanism Dynamics Analysis results.

• Open each Pro/ENGINEER component that was created from motion skeleton bodies.
• From Pro/ENGINEER main menu access > Edit > Setup > Mass Props. Specify all the required properties as seen in Figure 9. After completion, click Generate Report from Setup Mass Properties definition window. Close the window.
  
  
• Access Pro/ENGINEER Mechanism Dynamics functionality (from main menu > Applications > Mechanism). Specify external loads/motors/etc and Dynamic Analysis settings. Run the analysis and specify measures. Notice that there is no change in results (Figure 10) when analysis runs with 3D solid geometry versus a model with assigned mass properties.