Firearms Simulation in Ansys: Part 1 - Geometry Cleanup in SpaceClaim
Hi everyone, this is Mingyao from Ozen Engineering, Inc. I'm going to be doing a series of videos on using ANSYS simulation software to model firearms design. In this video, I'll start by looking at a geometry and doing some cleanup. Future episodes will cover:
- Explicit dynamics analysis to examine the motion of projectiles and mechanisms
- Rigid body dynamics and kinematics simulations
- Firing analysis with Olarion solvers
We're starting with a model I found on GrabCAD. I want to give a shout-out to the GrabCAD community for providing a wide range of CAD models ready for download. Special thanks to Tony for creating the Desert Eagle assembly that I'm using for analysis. These models are excellent and far better than what I could create. Thanks again to everyone contributing to the community.
Geometry Cleanup in SpaceClaim
In this video, I'll demonstrate how to clean up geometry in SpaceClaim. Often, CAD models used for design aren't necessarily suitable for simulation. One key aspect is reducing the parts to those we want to simulate. Here's how we can approach this:
- Start by hiding or deleting parts not needed for analysis, leaving only the components we wish to simulate or modify.
- Use SpaceClaim's cross-sectional view to identify overlapping parts. For example, if a part overlaps in the cross-section, you can select and move it to resolve the interference.
- Address issues like misplaced pins or overlapping components by adjusting their positions.
- Select components unnecessary for analysis, such as helical springs, and delete them.
- For linked components, make them independent to move them separately.
One of the first steps is to reduce the simulation to a set of components you're interested in modeling and ensure no interferences exist. For instance, if there's overlap between parts, resolve it by selecting and moving the components accordingly.
Setting Up the Simulation
To set up the simulation:
- Hide parts you won't analyze and select the necessary components for your simulation.
- Suppress unnecessary components for physics, ensuring they remain in the simulation but aren't included in the physics calculations.
- Consider creating a symmetry plane to reduce computational cost by modeling only half the simulation.
- For thin parts, use mid-surface tools to simplify the model by focusing on the internal surfaces.
After cleaning up the model, you can proceed with setting up the simulation. For example, you might pull the back part of the gun backward with the firing mechanism and push it up with the spring to load the bullet into the chamber.
Conclusion
This video provided a quick overview of setting up and simplifying a model for analysis. In the next video, I'll show you how to set up a loading simulation with all these bodies using ANSYS Explicit Dynamics.
Thank you for your attention. If you liked this video, please subscribe and watch out for more videos coming. Thanks and have a good day!
Hi everyone, this is Mingyao from OZ Engineering. I'm going to be doing a series of videos on using ANSYS, showcasing different aspects of ANSYS simulation software to model firearm design. In this video, I'm going to start with looking at a geometry and doing some cleanup.
I'll be covering in future episodes the explicit dynamics analysis to look at motion of projectiles and mechanisms, as well as rigid body dynamics kinematics simulations and firing analysis with Olarion solvers. We're going to start with this model I found on GrabCAD.
I want to give a shout out to the GrabCAD community for having a wide range of CAD models ready for downloading. Specifically, I want to thank Tony for creating this desert eagle assembly that I'm using for analysis. These are all really nice models and far better than what I can create.
So thanks again for everyone for contributing to the community. In this video, I'm going to be looking at how to clean up this geometry in SpaceClaim. Often, CAD models used for design aren't necessarily applicable or good for simulation.
One of the key things we don't like in simulation is geometry that's not suitable for analysis. So we're going to start with the first step: reducing the parts to those that we want to simulate.
I can, for example, start hiding parts or deleting them for analysis purposes, leaving only the mechanism or the components I like to simulate or modify. One of the really handy tools SpaceClaim has is the ability to work in the cross-sectional view.
For example, I can see this part is overlapping with this cross-sectional view. I can triple-click the barrel, which selects this part, and then choose the cross-section I want to bridge. I can move this component slightly to avoid overlap.
At this point, we're going to be working on the lower cover part. This one will have a double sub-assembly and it looks like it includes the bolt guide pin as well as the ejector and a whole bunch of other things. We can choose to move all of them or just one at a time.
Let's move this and slide it back, for example, or grab this whole assembly and move it backwards to remove interference. This is one way of simplifying the model. Let's now move on to resolving interferences.
One of the first things we want to do is reduce the simulation down to a set of components that you're interested in modeling and then make sure there are no interferences so that the analysis can proceed forward.
If I want to do a simulation that includes just this part and this part, I usually start by hiding the parts that I know I'm not going to be analyzing. I can then select and move these to a new component and suppress them for physics.
Now these components are still in the simulation, but they will not be included in the physics. For thin parts like this clip, it's helpful to do a mid-surface. We can choose to pull surfaces in and move them along the edge. Now we don't have to model the thickness; we can just model the inside.
Now if I look at my model, this is the part I want to simulate in my analysis. I can pull the back part of the gun backwards with this firing mechanism and push this up with the spring so that the bullet loads into the chamber, for example.
That's a quick description of how I would go about setting up and simplifying a model for analysis. In the next video, I'll show you how I set up a loading simulation with all these bodies using SSExplicit Dynamics. Thank you for your attention.
If you like this video, please subscribe and watch out for more videos coming. Thanks and have a good day.
