Below is a recording of me making ik redirects, as well as text compilation:

Using IK (Reverse Dynamics) to redirect animation sequences in Unreal Engine (UE), character animation can be accurately adjusted and dynamically adapted. This is often used to adjust the fit of an animation between different skeletons, or to dynamically change a character’s posture at run time to suit the environment. Here are the detailed steps and methods:

1. Ensure skeleton compatibility:
   Make sure the skeleton of the animation sequence is compatible with the skeleton of the target character. If the skeleton is not compatible, you can use Retarget Manager for skeleton redirection.
2. Prepare the animation sequence:
   Make sure the animation sequence is properly imported and aligned with the skeleton. You can verify this by looking at the animated preview in the skeleton asset.
   IK Steps for redirecting and applying animation sequences
   Step 1: Create a new ik rig to open the target character’s skeleton assets.
   In the Skeleton panel, click Retarget Manager. Set up the skeleton and ensure that the joint mapping of the source and target skeleton is consistent. Save the Settings to ensure that animations can be shared between skeletons.
   Step 2: Create an IK retarget
   Make sure that the skeleton IK control points of the original character are consistent with the IK control points of the animated character. If desired, you can edit the skeleton and add or adjust the skeleton.
   Step 3: Apply the animation sequence
   Open the target character’s Anim Blueprint.
   In the Anim Graph, add the Animation Sequence Player node: Select the animation sequence to use. Connect the Output to the character’s final Pose node (such as Output Pose). Make sure the animation blueprint drives the character’s posture properly.
   Connect the input of the IK node to the Animation sequence output, and connect the IK output to the Final Animation Pose.

Import motion capture data and modify it – dance animation

By modifying the imported motion-capture data, I made changes to the character’s dancing movements.
In this process I encountered some problems that I did not encounter when animating with maya, for example: since it is motion capture data, the amount of data is very large, each xyz axis has a corresponding data point, if you modify one of them, you must modify all three together, otherwise there will be some motion problems.

Importing motion capture data in ue also needs to pay attention to the following key issues, which I will encounter when making import animations and modifying:

1. Skeleton compatibility
   Bone name and structural consistency
   The motion capture data (usually imported in FBX format) needs to be consistent with the skeleton of the target character. If the bone names or hierarchy do not match, it may result in animation application failure or posture deformity.
   If the skeleton is inconsistent, bone mapping can be done through Retarget Manager. Make sure the skeleton of the motion capture data has the same proportions and joint orientation as the target character skeleton.
2. Animation cleaning and correction
   Noise issues with capturing data: Noise or abnormal movements (such as jitter or joint penetration) may be introduced during motion capture. Before importing UE, you need to clean it up in Maya.
   Jitter removal: Handled by smoothing filters or manually correcting joint curves.
   Key frame optimization: Reduce redundant key frames and keep animation smooth.
   Ground penetration and floating issues: The motion-capture data may have characters with their feet off the ground (floating) or their feet on the ground. Fix it: Use UE’s IK foot correction function to make sure your foot fits the terrain. Or adjust the joint position in the animation editing software to ensure accurate foot movements.
3. Root movement problems
   Root bone trajectory and Motion adjustment: Root Motion is commonly used in motion capture to drive the overall displacement of the character. If the root bone movement trajectory is abnormal (such as too fast or inconsistent), it needs to be corrected: Check and adjust the root bone trajectory in maya, enable or disable the root movement in UE, depending on the specific needs.