animation problem

i made this animation ,i went to frame1 and selected the gate and then select loc and locrot, then i went to frame 60 moved the gate up and select loc . then i selected the gears and rotated them 175 degrees and select locrot ,but the result are weird and i don’t know why i get this

You want to set a keyframe for both the gate and the gears at frame 1. If (for example) the gate is only changing location (and not size and rotation) then it’s better to just use a LOC IPO (and so on the gear only a ROT IPO). Then you move the gate to the end of it’s travel and I-Key another LOC.
The gear is a bit different because, if you move it 1440 degrees (4 turns = 0-360 x4 where 360=0 so blender reads 0-0x4=0) your gear, although you turned it 4 times it’s back where it started.

You want to work out how many degrees it turns between frame 1 and 60, divide that by 90deg or 180 deg rotations and add keyframes there.


thanks i’ll try that

i have tried but i can’t get it to work. now i went to frame 1 ->locrot then i went to frame 31 and rotated the gear 90 degrees but the results are the same and the ipo curve is strange

You can try this script:

Or, if you want to move onto 2.40 animation capabilities:

It will only work in one of the 2.4alpha builds though.

But, essentially, your setup is easy to Key. You move both gears and the gate down to their frame1 position and line the teeth up with the rack. Select the Gate, I-Key and a Loc key. Then select 1 gear and do a LocRor, and the same on the other gear.
Now work out which teeth on both gears will slot into which teeth on the rack half way up, move the gate and 2 gears up and line the gear teeth with the Rack teeth on their marks. Do another Loc key for the gate and LocRots for each gear. Then move them to the top and do it again.


To avoid confusion, I’d make sure I pressed Alt-C (or is it Alt-S?) to remove any rotation on the gears. This may be confusing the issue as to the correct axes.

Alt-C (or is it Alt-S?)

Almost there; Ctrl-A.

(Alt-C is convert to mesh and Alt-S is Clear Size.)


Hehehe. At least I was on the correct part of the computer! (the keyboard, that is!) Close enough, surely! :smiley:

this time i didn’t move the gate all the way up but i went to frame 10 and moved the gate and the gears up two teeth . then for the gate loc and i rotate the laft gear on the left 2 teeth and the right gear on th right 2 teeth . i did this another time and it was ok but then i did i another time but this time the right teeth was breakdancing . i don’t know why it happens becouse i did the same thing on the left and right gear ,i only rotated them in different directions .

Well, I think it looks cool like that… :wink:

have you examined the IPO curves of the gears to make sure there are no anomolous keyframes, or something like that?

It’s turning around the Z axis at the end. You can safely find the RotZ IPO in the IPO window and delete it.

If you want me to take a look at the file either upload it or send it to me ([email protected]) and I’ll write in the Text editor what I do to it and send it back.


Fligh % :

i have sent the file to your e-mail so if you have some time take a look at it , thanks

Sent it back.


thanks a lot