Importing FBX animation from a tool could be a tricky. It is really not easy, especially for a beginner. If you want to learn to import the FBX animation, please read all the entire article about importing FBX animation.
In general, you are able to import FBX animation into Roblox with baked animations. However, FBX export options have different methods across software. Here is the details to import FBX animation:
- 3D Max
Apparently, Character Animation Toolkit rigs are supported but have to be exported a particular way. If you want to export the animation that is made using CAT, please make sure you do the following. Before you try to export, you have to make sure that you are not displaying any bones as a box. Then, choose the object or bone, right click and go to Object Properties. Keep in mind that Display as Box can cause the FBX export error. When you export the animated model, you only have to choose the Model not the bones. It is said that any CAT bones that are skinned to the mesh will be automatically exported. In the FBX Settings, you need to check Convert Deforming Dummies to Bones. If not, it will cause the error and your bones will display as geometry.
There are a plenty of ways to import FBX animation from Blender. One of the ways is explained by a Youtube channel called AndreyPlaying. Here are all the steps to do it according to the channel. First, open the tool called Blender and make your model. Second, be sure there is no more that 5000 tris or Roblox will not import it. Third, press File, press User Preferences and navigate to Add-Ons tab. Fourth, type in “FBX”. Do not forget that you need this adds-on because that is the only way to import mesh in Roblox. Fifth, be sure the scene is clear by deleting camera and lights. Sixth, choose the object and head to File > Export > FBX. Seventh, right click and head to Insert Object > Mesh part when you are in the Roblox Studio. Eighth, press on Mesh ID and look for your object.
Apparently, once you bake the rig your model will be contained wihin the hierarchy. In this case, you need to grab this item and drag it out of the hierarchy to be a top level item. When exporting, please make sure that you have only that main model selected. The whole hierarchy and any child objects such as eyeballs, teeth, and so on will automatically export into your FBX.
By default, it is best for you to use the Game Explorer option located under the File menu for exporting, and especially when you want to upload a couple of animations to the model. You can add the clip name and the Start and End of each animation. This step will package all your animations into one file. For those who have the complex rigs with a lot of hierarchy and controls, the another option is using the Export Selected for FBX.