Define your available spaces into Rigging mode…
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As a case in point, we are going to animate a classic juggling act, making use of Space Switching in akeytsu.
In rigging mode - and in Bind Pose, we’ll start by defining possible spaces. Click space icons opposite to joints in Picker to enable them as new spaces. For juggling we’ll activate Wrist_R, Wrist_L and Root.
… And then start to play with space switch directly in your animations!
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Switch over to Animation Mode and start a new animation.
Concerning the joint we want to space switch (in our case - Potion_Healing) we’ll first create/extract a MRS layer (Move, Rotate, Scale) that will contain the MRS keys.
Then, we will use these MRS keys to position our object at the desired place (in our case - the hand). Once the object is correctly positionned we’ll create a Space Switch layer (that will contain the Space Switch keys).
The goal is to have - at least - one MRS key with the targeted joint at that time in the timebar so, when you create your space switch keys, be sure that you have a corresponding MRS key below/above at this time. That’s the rule guys !
Creating a Space Switch key will automatically open the Space Switch dialog where we’ll set the space we want to switch our potion (here - Wrist_R).
And that’s it! Now, on this keyframe, the potion will follow the hand.
When creating your following Space Switch keyframes, we recommend to rather use the Timebar than the Stacker. Position the time cursor right at the MRS key time and RMB click/Create Space Switch key. This way, you’ll have perfect synchronisation.
If you break the synchronization between MRS and Space Switch keys, a tiny warning icon will be displayed to clearly indicate you to fix it.
However there are some rules to move/retime your keyframes safely.
Indeed, you must keep in mind that a MRS key must stay in his current space meaning, depending on you want to speed up or slow down your animation, you won’t proceed the same way.
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If you need to slow down your animation, move first your MRS key(s) and then your Space key(s)…
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… while if you need to speed it up, move first your Space key(s) and then your MRS key(s)…
In our juggling animation, we used 3 space switch keyframes.
The Potion joint is Parented (by default) to the Root joint, the Potion joint is first space switched to the Wrist_R joint, then to the Root joint (“flying” period) and finally to the Wrist_L joint (plus a loop key at the end).
Of course, you can update the space of existing keyframes. In order to do that, select your keyframe, go into the Transform window and click on the Space Switch channel. That will open the Space Switch dialog where you’ll be able to redefine your space.
Enjoy 
!