Understanding the RBD Solver in Houdini

Rigid Body Dynamics can be confusing. Luckily we have you covered with everything you need to know to get started with the Bullet Solver in Houdini 18.5.

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Rigid Body Dynamics Made Easy

Rigid Body Dynamics have changed slightly inside of Houdini 18.5. With that being said most of it is pretty similar but just has different nodes and a different workflow. Whether you are new to Rigid Bodies inside of Houdini or just looking to brush up on the new workflow so you can finish up a project we have you covered.

In our introductory video to the Bullet Solver and Rigid Body Dynamics we go through the initial set up. We cover the basics of the Bullet solver as well as the RBD Material Fracture node. The Material Fracture node has some nice default settings that can get you started with a few different materials like wood or concrete. This introductory video is a good place to start if you are completely new to Rigid Bodies inside Houdini. If you are a more experienced user you may want to skip this initial introduction but the follow up videos provide some easy solutions to more advanced issues you may run into.

The second video in this series shows you how to control the fracturing of your materials. We go over how you can set the number of fracture points, control their over all placement and for specific materials where you need exact control, like glass, we show how to set the exact position of the fractures.

After the second video of this series you should have a pretty decent understanding of the basics. The third video covers how to enable collisions of other objects with your main geometry inside the bullet solver. The fourth video takes this one step further by illustrating how to enable animation on those collision geometries. Towards the end of the fourth video we discuss how to use multiple collision geometries of different types. One object we keep static while another we add animation to. The third object is simulated as if it were a normal object with gravity.

Building upon everything that has been shown so far, the fifth video shows how to simulate a pile of debris using the Bullet Solver. This video is for more advanced users as it covers everything from the last videos while also solving some major issues that you may experience. One such issue is the Bullet Solver seeing multiple objects as connected when they should not be. 

By the end of this series you should be prepared to tackle Rigid Body Dynamics inside Houdini. If you have any questions or any issues please feel free to let us know in the comments of these videos as you probably aren’t the only one who has come across the issue or had that question. Your question or issue might just become a video itself.