Blender 3D：第四单元：与高级教程起飞

Using the floor constraint will keep a bone from passing through an object from a given direction. It is useful when making floors of course but also when making walls and other items which are obstacles for the armature.
::使用地板约束将防止骨从特定方向穿过物体.当然,它在制造地板时也是有用的,但在制造墙壁和其他对具构成障碍的物品时也是有用的.

There is also an offset value which is very useful when say for example you have a foot where the mesh stretches down below the actual tip of the armature you can then use the offset to make the bone stop before it actually reaches the obstacle object.
::对于一个脚, 网格可以伸展到具实际尖端以下, 您可以使用此位移来使骨头在实际到达障碍物之前停止.