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Question Animation Rigging - Multi Rotation throws off Hand & Arm position from IK targets

Discussion in 'Animation Rigging' started by acMacav, Jan 1, 2024.

  1. acMacav


    Apr 1, 2018
    Hello Everyone,

    I’m currently using Animation Rigging for animating characters and objects during Cinematics made with Timelines and Sequences, rigging the characters in a way so that they’re able to move their hands/feet with Two Bone IK targets as well as their Head and Upper Body by having Multi-Rotation set on each of the spine bones on a character’s body, with the source object being their head, and when the character moves their head via Multi-Aim target, their spine rotates according to their head position as needed to create much more fluid upper-body movement within these cinematics.

    The problem that I’m encountering with Multi-Rotation being set up on the spine and having the body move and orient to follow the head with it's Multi-Aim target, is that the position of the arms and hands move away from their hand IK targets.

    The Hand IK targets themselves are Multi-Parented to empties, which these empties are child objects of another character's spine bone, and then these empties are animated for challenging animations where a character needs to get onto or hold onto an object/character while they also move. What I want to have happen is that as a character’s upper body moves, their hands and arms stay in place with the Hand IK targets on those Multi-Parented empties, rather than being overwritten by their spine Multi-Rotation as shown below.
    01 - MultiParent throws off hand positions from their IK targets.png

    10 - mRotation setup.png

    I have the character rigs set up so that the Multi-Rotation is further down the rig hierarchy than the HeadLookatIK and Hand IK targets, but I'm not sure if this is a hierarchical issue, constraint issue, or if I’m missing something with how I’m animating the empty targets that the character's Hand IK targets are also Multi-Parented to.
    07 - Player Rig Heirarchy + Targets.png
    09 - ToppoTargets.png

    Any help on this would be greatly appreciated, thanks!
    Last edited: Jan 3, 2024
    brian-nielsen likes this.