Stutter / going backwards during animation

[N_M_Hawthorne]

Sometimes I'll create a path for an object to move along, then when I render the scene the object will sometimes slow way down along the path or even sometimes go backward.

What causes this, and how can I limit it from happening?

Thank You
N.M.

[A Lindsay]

It's because the keyframes are too close for the path on the timeline. The velocity is off due to the implicit keys.

You can adjust the beziers, make sure you don't have two keys on top of each other, switch to linear/natural interpolation and then back to bezier.

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