Using a scaled version of a knuckle design, SOLIDWORKS Technical Manager Mike Sande demonstrates how to get the most out of your design to cut materials, reduce mass, increase confidence in the durability of your design and better understand the life cycle your product will endure. In just 15 minutes, he uses three iterations through Simulation to create a good design, a better design and the best design for this product.
Optimization is key when it comes to creating a design that is going to last. To begin, we look at our known variables: a geometry created in CAD software and an input to Simulation. Aside from this, you have information on materials, which are easily defined through the Simulation database. Type of material, mass density and yield strength are all made known to you, along with the actual placement of your part within the model.
Another piece of information that is relevant throughout this process is the known force. By knowing the load your piece will be placed under, you will know how to best equip it to handle this weight. In this case, there is a 25,000 pound force that Mike is trying to design this object to withstand. He is just missing the optimal angle.
The “Good Design”
Will your design break? This is a step in the “Good Design” stage where using a Linear Static Analysis will find the worst case loading scenario while moving to the next stage of optimization. Begin by creating a New Study, and enter all your known variables; for Mike he created the knuckle mentioned earlier. From here, you will actually apply a load in order to begin testing for that missing optimal angle. Once you apply your direction of the load and change your Sensor Type to Simulation Data, you can then run a test. What you will be looking for is the Factor of Safety. By modifying variables and constraints, Simulation will run multiple tests. These scenarios change the direction of the load to see how the stress on your part is affected based on the Factor of Safety requirement you set.
By examining the data produced in these scenarios Mike pinpoints the optimal angle as well as its location, giving an exact number for the place of max stress as the part shifts through its range of motion. Checking this information against the full model gives you a better understanding of the design.
The “Better Design”
Making a design that works is just the first stage of the process, now it’s time for improvement. Let’s find the “Better Design.” Varying the geometry this time, as opposed to the load, will allow you to understand more behind your design and the ways to strengthen it. Mike changes the Flange thickness and Internal Fillet since we found out the most stress was occurring within these aspects in the “Good Design” tests. Like the last design, run your worst case scenario to find the Factor of Safety, then use it to optimize by changing those variables and constraints to run test scenarios.
Once these scenarios are run, you will quickly see which design combinations fail and soon find your “Better” optimal design.
The “Best Design”
We saved the best for last. You’ve run the tests and reduced both the materials used along with the overall mass. Now it’s time to validate. Mike does this by looking at the overall life cycle and trying to prevent failure in the design. In this case, a Fatigue Study was run using the”Better Design”, looking at 100,000 cycles of loading and unloading on your part. You’ll now see where failure has occurred. This can be used for warranty information or to continue optimizing the design. Question all aspects of failure in the design to best provide quality parts for your optimal model.
So what’s the takeaway? Design itself is great, but with a few extra steps you can take your design from good, to better, to your best, most optimized design yet. By simply running worst case scenario, testing that scenario with changes in variables and constraints and then analyzing the trends presented in the data, you can create a wealth of information to validate your design and make the necessary improvements.
Use SOLIDWORKS Simulation today to create your best design yet!