“Fixed Joints” refer to a function to connect objects together. It is the simplest form of all Joint Components.
“Friction Combine” refers to a calculation method of friction coefficient (magnitude of friction). The magnitude of friction between two colliding objects is calucated in the following four ways:
1) Average: Take the average
2) Minimum: Take the smallest of the two values
3) Maximum: Take the largest of the two values
4) Multiply: Take the multiplied value.