Unity’s animation system allows you to control the range of motion of different bones using Muscles.
Once the Avatar has been properly configured, the animation system “understands” the bone structure and allows you to start using the Muscles & Settings tab of the Avatar’s Inspector. Use the Muscles & Settings tab to tweak the character’s range of motion and ensure the character deforms in a convincing way, free from visual artifacts or self-overlaps.
The areas of the Muscle & Settings tab include:
For the settings in the Muscle Group Preview and Per-Muscle Settings areas, you can preview the changes right in the Scene view. You can drag the sliders left and right to see the range of movement for each setting applied to your character:
You can see the bones of the skeleton through the Mesh.
You can enable the Translate DoF option in the Additional Settings to enable translation animations for the humanoid. If this option is disabled, Unity animates the bones using only rotations. Translation DoF is available for Chest, UpperChest, Neck, LeftUpperLeg, RightUpperLeg, LeftShoulder and RightShoulder muscles.
Note: Enabling Translate DoF can increase performance requirements, because the animation system needs to perform an extra step to retarget humanoid animation. For this reason, you should only enable this option if you know your animation contains animated translations of some of the bones in your character.