Problem to keep stopped

Hello guys. I want to animate the charles. I do the next: keyframe 0f initial position (close), keyframe 2f open, keyframe 4f initial position. I want to repeat in half second, so I duplicate keyframes like this: 12f as 0f (it is for avoid that charles open progressive from 4f to 14f), 14f as 2f and 16f as 4f. Oddly, from 4f to 12f it moves (it bounces). How can I do for avoid this movement?
Thanks.

Hola Genete. Te lo pongo en español por si no lo he escrito bien en inglés. Intento hacer que se mueva el plato superior del charles. Hago lo siguiente: keyframe 0f, posición inicial (cerrado), keyframe 2f charles abierto, keyframe 4f, posición inicial. Como quiero repetirlo en medio segundo duplico los keyframes: en 12f duplico 0f (para evitar que se vaya abriendo desde 4f hasta 14f), en 14f duplico 2f y en 16f duplico 4f. Curiosamente al renderizar, desde 4f hasta 12f, el plato superior desciende y vuelve a subir (como rebotando). ¿cómo hago para que continúe en la posición inicial desde 4f hasta 12f?
Gracias.
animando bateria para banda jazz.sifz (31.1 KB)

Easy peasy, just change the out interpolation of the 4f waypoints to constant or linear.
Default is TCB interpolation which gives smooth curves which goes through the waypoints creating a dip on the other side. You want to break this so the curve is just flat on the other side of the waypoint.
Open up the Curves panel to see how your changing of interpolation effects your curves.

Hi Rafael,
the default interpolation for waypoints is TCB what gives a smooth interpolation between waypoints. But the TCB interpolation curve uses the information from the previous and next waypoint if they exist. To avoid that bounce you have to edit the waypoints in the frames 4f and 12f. what you need is a linear variation between 4f and 12f that doesn’t take account the previous and next waypoints. Each waypoint (and thus each keyframe) has two sets of values: “In” values and “Out” values. They define the interpolation before (“In”) and after (“Out”) the waypoint. So you want a TCB “In” for the waypoint in 4f and a Linear “Out” for the waypoint at 4f. Similar to 12f. You need Linear “In” for the waypoint at 12f and TCB “Out” for the waypoint at 12f.
As you probably have lots of layers and lots of waypoints in each layer you can do it easily by editing the keyframe properties.
Select the keyframe at 4f and press the Edit Keyframe button in the keyframe panel. Check the “Out” side and set it to Linear.
Same for 12f. Select the keyframe at 12f and press the Edit Keyframe button in the keyframe panel. Check the “In” side and set it to Linear.

That should solve the bounce problem.
Greetings.
-G

EDIT: OK, rylleman said the same more quickly and more concisely :wink:

Hi, guys. It works fine. Thanks a lot. I hope i’ll finish my little animation in a few days. Now it’s time for the double bass.