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Subsubsection 8.3.2.4: Problems due to Contact Up Chapter 8: Troubleshooting Subsection 8.4.1: The penalty method

## 8.4 Guidelines for Contact Problems

FEBio offers many contact interfaces which allow the user to model complex boundary interactions. However, this capability comes at a price and the use of contact interfaces may create several problems in the solution process. It is hoped that the guidelines presented in this section may prevent many of the most common problems with contact.
Most of the contact algorithms implemented in FEBio offer two contact enforcement methods: a penalty method and an augmented Lagrangian method. Since the strategies for these two methods are slightly different, we will look at them separately. These algorithms are discussed in much more detail in the FEBio Theory Manual.
Subsubsection 8.3.2.4: Problems due to Contact Up Chapter 8: Troubleshooting Subsection 8.4.1: The penalty method