If you need to design a framework structure and the strength and rigidity of this structure is critical, you’ll want to have a good idea of how the design will perform before creating the actual details of the framework. Pro/ENGINEER Mechanica offers a great method of looking into this.

First, inside Pro/ENGINEER, using datum curves to create the basic shape of your framework.

Then take this part into Pro/ENGINEER Mechanica Structure Applications > Mechanica. 

Use the Beam tool    to assign beam idealizations. Simply walk down the Beam Definition dialog box to setup your analysis. First select the curves you wish to include in the first set of beams. Then assign the material for these beams by selecting More... 

Pick and select your desired material from the Pro/ENGINEER materials library.

The next step is to assign the Properties of the beams, specifically their type and orientation. To do this, we first need to assign what is known as the “Y-Direction” for our analysis. Display your coordinate system.  Note the direction that would be considered “out of the screen” for your selected curve entities (in the displayed case below it is the Z-direction). In the dialog box assign a “1” to that axis and a “0” to the other 2 axes.

(This may seem counterintuitive as you are assigning the Z-axis as your Y-direction, but trust me, it works.)

Now you will define what type of beams you will be using. Select the More… button next to Beam Section, then New… in the next dialog. This will bring up a window for defining the shape of your beam. 

Select the Type (I-Beam, Rectangle, Channel, etc…) and provide the dimensions of the section. 

Select OK in all the dialog boxes to see the result.

To adjust the orientation of the beams, select the Beam Idealization either in the graphics window or in the Model Tree under ‘Idealizations’. Right Mouse Button > Edit Definition. 

Select the More… button after Beam Orientation. Select the New… button in the next dialog. Now assign the appropriate angular change to your beam. (In this case we will change its orientation by 90º).

Select OK in all the dialog boxes to see the result.

You can repeat this procedure to assign the same or different beam cross-sections and orientations to the remaining segments of your design. Once you have assigned Beam Idealizations to all your entities (as in the model shown below) you can assign loads and constraints.  



While there are many different methods of constraining a design, we will step through one simple method:

points to site the exact location.) In the case below we have completely constrained the bottom 2 points.

• You can allow additional degrees of freedom in your constraints if necessary by altering the toggles at the bottom of the dialog. 

• When finished, select OK.

While there are many different loading cases we could apply to a design, we will step through one simple case:

• Select the button Force/Moment Load.
  
• Change the References selection to Points. 
  
• Pick the points on your model where you wish to apply your loading case. (Again you may want to create

datum points for exact location).

• Define the Force/Moment to be applied in the bottom of the dialog box assigning the proper X, Y & Z components of the Force/Moment. Simply use negative to reverse the direction. Be certain to assign the proper units of your load as well.
  
• When finished select OK. 
   

The design is now ready for a static analysis. 

Select the Mechanica Analyses/Studies icon  from the toolbar.

In the dialog box select File > New Static. The default settings in the Static Analysis Definition dialog box should be fine for our purposes so select OK. 

Then select the Run Icon  in the toolbar.

Now Pro/ENGINEER Mechanica will solve your analysis. If you are using Pro/ENGINNER Wildfire 5.0, a Diagnostics window will appear and provide you feedback on your model and the analysis you are performing. It will also tell you when the analysis run is completed, which should not take much time at all. Pro/ENGINEER Mechanica solves for an accurate answer very quickly.

It should be noted that unlike some other analysis tools, Pro/ENGINEER Mechanica users can continue working on their model while the computer is working on the solution to your analysis. The analysis runs in the background and does not tie up the Pro/ENGINEER and  Mechanica Interface.

Once the “Run completed” appears in the dialog, select Close on the diagnostics window.



















Now review your results. 

Select the Results icon.  In the new interface that appears, select the Results icon  and select your analysis (by default it will be named “Analysis1”) > Open.

You then define what you want to see in the results. Most commonly users set the Quantity to either Stress or Displacement, being certain to set the appropriate units display and component. 

Select the Display Options tab, toggle on Continuous Tone, Deformed (set the Scaling to “1”) and toggle on Animate.

Once satisfied with your Window Definition, select OK and Show. The resulting window should display an accurate portrayal of the performance of your design.

Explore the tools available to you under the Format and Info Menus such as Model Max, Model Min, Dynamic Query and formatting of the Legend. Note that to use most of the tools in the Info menu you will need to turn off the Animate setting. To do this, or to alter any of the Window Definition settings, select the Edit Definition icon.  You can also add multiple windows by defining a new Window Display using the Results Icon .

Now that you know this method, you can make alterations to the design’s original structural shape or change the type and orientation of your beams until you have a design that performs to your specifications. Of course it is recommended that you still test your final detailed design, but this method can quickly and easily put you on the right path to a structural framework design that meets your exact needs and specifications.

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