Adding Virtual Connectors in Altair SimSolid

Altair SimSolid is a game changer when it comes to reducing preprocessing, specifically its meshless technology and its automatic contact and fastener creation. One of the great workflows in SimSolid is when importing fasteners, SimSolid will automatically recognize the fastener geometry and create a fastener connection. However, in some instances you may have parts which do not have associated geometry for fasteners, so users will have to manually create the connector in their simulations. In today’s blog, I am going to highlight how to create a virtual connector for a bolt circle (Figure 1) in both SimSolid Desktop as well as doing it in SimSolid Inspire.

Figure 1: Bolt Circle Model

For those of you unaware, Altair has implemented the SimSolid Solver into Altair Inspire, so users can take advantage of Inspires CAD and modeling capabilities. If you currently have a units-based license of SimSolid, you can take advantage of Inspire, and it’s a great tool to utilize for CAD and modeling manipulation. For more information, check out the following videos on Inspire.

Creating Virtual Connectors in SimSolid Desktop:

As was previously mentioned, the beauty of SimSolid is upon importing CAD it will automatically recognize fastener geometry. My recommendation is to have all of your fastener geometry modeled in your designated CAD tool prior to importing into your SimSolid project, this will ensure that all fasteners are created automatically. However, there is a manual way to create virtual fasteners in SimSolid Desktop if you do not create the fastener geometry in your CAD tool.

In our case we will import our bolt circle model into SimSolid Desktop. We then click on the connections option in our design tree and click on the virtual connector icon (Figure 2). Within SimSolid Desktop users can create Pins, Bolts, Remote Supports, Bushings, Cable/rods, Rivets, Joints, and Superelement connectors. In our case we have a bolt circle so we want to apply bolt fasteners, so we can apply one of two connectors to represent a bolt, either the pin virtual connector or the general connector. The primary difference is with the virtual pin connector, users can specify if it’s a rotation/sliding/bonded contact, whereas the general connector implements a rigid contact on the faces you apply it to. Depending on the type of bolt you are applying, apply the appropriate connector that matches up with how your bolt contacts perform in reality!

Figure 2: SimSolid Desktop Virtual Connector Options

The caveat of applying virtual connectors in SimSolid Desktop, is it requires the user to click on each face you want to apply a connector to (Figure 3). As you can imagine this process can sometimes take time, especially if you have numerous connectors to apply. As I suggested previously, if you can import the fasteners into SimSolid Desktop it will save you substantial time. However, if you cannot create the fastener geometry in your CAD tool, there is a nice, automated feature in SimSolid Inspire where it will automatically recognize any holes and create the virtual connector for you. I will run through those steps now!

Figure 3: Manual Virtual Connector Process in SimSolid Desktop

Creating Virtual Connectors in Inspire SimSolid:

As mentioned above, SimSolid is also implemented in Inspire, so we will open up Inspire to aid in our connection modeling. In our case, our primary purpose will be to utilize Inspire’s automated fastener modeling to apply all of these fastener connections quicker than we would have to do in SimSolid Desktop. Our first step will be to open Inspire and then make sure we turn on the SimSolid solver from the Inspire preferences (Figure 4).

Figure 4: Altair Inspire Preferences to set SimSolid as Solver

Now that our solver has been set in Inspire for SimSolid, we can import our bolt circle model, and utilize the automated fastener creation tool in Inspire. We can navigate to the Structure ribbon in Inspire and then click on the Fasteners icon (Figure 5).

Figure 5: Fasteners Icon Location in Inspire

As soon as we click on the Fasteners icon, Inspire will automatically search your geometry to find any holes. Inspire looks for holes based on the size settings user specify, in my case I will utilize the default search tolerance, but I have the flexibility to change it (Figure 6). Immediately after searching for holes, Inspire will find the holes which are highlighted in red. If for whatever reason it does not find a hole or it finds a hole you do not want a fastener at, you can select/deselect holes accordingly. In my case the search found all holes that I want to have a fastener at, so I will hit the checkmark to accept the fasteners. I can now see my newly created fasteners (Figure 6), note these fasteners will show in my structural tree under the connections.

Figure 6: Left: Fasteners Options for Fastener Creation, Right: Newly Created Fasteners

At this point, we are now ready to apply the boundary conditions in our model and solve. I am going to apply a basic linear static model, with an interior pressure on both faces, and a steel material for both parts. SimSolid Inspire till harnesses the same SimSolid Desktop solver, so I do not need to mesh my model and the model will still solve very quickly. After solving, I can visualize the results utilizing Inspires post-processing tools. The post-processing tools in Inspire SimSolid will be visually different than SimSolid Desktop, but I will still retain all the necessary results I need. In my case I want to look at the forces on my fasteners, much like I would in SimSolid Desktop, I can do that by clicking on the Fastener Force Results Icon (Figure 7), after clicking the icon results will automatically be displayed. Fasteners will be listed in a table, and if I apply a call out, I can visually point to what the table results summarize for reach fastener (Figure 7).

Figure 7: Altair Inspire SimSolid Fastener Results

I hope this blog has illustrated the power and ease of use in how you can apply virtual fasteners in either SimSolid Desktop or SimSolid Inspire. If you have any more questions about Altair SimSolid or any Altair solution, please reach out to us at [email protected]!