Childof Constraint Issues

Hi all,

I’m trying to animate an object (“Cube”) moving from one place to another by utilising the childof constraint linked to an empty (“Handle”). “Handle” is animated along a path and when it reaches the location of “Cube”, “Cube” will follow “Handle” via the childof constraint. Once “Cube” has reached the desired destination, it will let go of “Handle”. The problem is that once it lets go, “Cube” snaps back to it’s original position instead of maintaining it’s new position. The work around is to use a childof constraint to an empty for each pick up and drop off point, but when the number of "Cube’ objects and “pick up/drop off” points starts to go up , the number of objects quickly becomes unmanagable.

I’m unsure whether the problem is user error or a querk of blender that needs to be looked at. The childof constraint seems to give counter-intuitive results because it causes the object to revert to it’s original position instead of maintaining it’s new position.

Any suggestions would be greatly appreciated!

hi veefwoar,

Not sure if I am right on this, but I am thinking the childof constraint overrides the cubes location IPO, since the constraint moves the cube. So I am thinking, at the frame right before (or even the frame of) where the childof constraint no longer influences the cube, insert a location key for where the cube should end up. I know when a constraint is removed from a characters armature, the bones return to thier original position. I’m thinking the same thing is happening here…


Thanks for the response.

I tried your suggestion but the problem is that the transform properties of the cube remain zeroed and don’t update to the global position of the cube. Adding a keyframe as you suggest adds a keyframe for time x at 0,0,0 so the cube snaps back to it’s home position anyway.

When you add the key next time, choose VisualLocRot. The “Visual” sets a key at the location the you see the object, not it’s Ipo location which is still 0,0,0.

Thanks mate that works a treat! I always wondered what that was for, just one of the many things I had noticed but never gotten time to read up on!