Best procedure to Accomplish goal

Hey guys looking to learn about the best process or procedure to achieve my end goal, thanks in advance for your assistance, hopefully I am asking correctly.

Here is a picture of a small portion of this conveyor, it actually has many more rollers that would be in this but I figure these would be good enough as this is the Drive moving all other rollers (and rotating components) throughout the system.

I am attempting to create 3 animations containing all rotating roller and components;

Ramp up Rotation to rotating
Constant Rotating
Slow down rotation to stop

I believe to do this and export this to be used in Unity I would create Actions, but I am not sure exactly how to do this. I have tried researching multiple objects into a single action, but not sure if that is the correct route.

Again, thanks for the assistance, I’ll be glad to answer any questions to help anyone better understand what I am trying to do.

Thank you :slight_smile:

Hey, I don’t know anything about Unity, but if it uses actions that should be easy. When you ‘key frame’ something you create an action (action editor). So, you are going to animate your ‘Drive’ roller - give all the other rollers a ‘copy rotation’ constraint.( I would use ‘Axis Angle’ as your ‘rotation’ mode but you can use 'Euler", just make sure all the rollers are the same). Frame 1 > insert key frame (0 degrees), go to frame 61 > rotation 360 degrees > insert key frame, go to frame 21 > rotation 342 degrees > insert key frame, go to frame 41 > rotation 18 degrees > insert key frame, go to frame 22 > rotation 0 degrees > insert key frame, go to frame 40 > rotation 360 degrees > insert key frame. Now go to the “Animation” layout, change the 'Dope sheet ’ to the ‘Action Editor’, there will be the action name > hit the [+] sign twice - now you have 3 actions. So what your going to do is pic an action (say the first one with out the .001/2) > delete all but the first 2 key frames (so 1 and 21 are left) > re-name it to “start action”. Next select the next action name (something.001) > delete all but the 2 center key frames (so 22 and 40 are left) > re-name it to “constant action”. Lastly select the next action name (something.002) > delete all but the last 2 key frames (so 41 and 61 are left) > re-name it to “stop action”. The next thing is to modify those actions (key frames) in the ‘graph editor’ so they will behave properly. Select the “start action” in the ‘Action Editor’, go to the ‘graph editor’ and select the first keyframe (frame 1), > S (scale) 2 enter. Do the same for the “stop action” last keyframe (61). Back to “start action”, select the other keyframe (21) > V (handle type) > select ‘Aligned’ > R (rotate) until its one handle is over the curves line, do the same for the “stop action” first keyframe (41). Last, select the “constant action” select a keyframe (22) > T (interpolation mode) > select ‘Linear’, do the same for the other keyframe (40). Modify the frame length in the graph or action editor if you need to then “Stash” them.
Post back if you have any questions.

I revised my solution :upside_down_face:


Thank you very much for responding! Seems like I need to allocate a bit of my evening on this following you instructions :slight_smile:

I’ll keep you posted if I run into any issues!

Thanks again for you assistance, I appreciate the time you spent to write up this up.

Best regards,

If the animations consist of nothing than simple rotations wouldn´t it be more reasonable if you did the animaton in Unity?

I don´t now anything about Unity but if i had to do this in Unreal i´d simply do the animation there because it would be more flexible.


This worked out really well! Thank you very much for your assistance!

The next step I am trying to figure out is have a Conveyor Belt rotate around the enter setup of all pulleys, and that one is certainly difficult.


Thats the easy part, a ‘Curve’ (beziercircle) , a mesh object (plane) with an ‘Array’ mod and a ‘Curve’ mod, animate the 'plane’s “X” location. Getting it to match the roller speed might be the harder part, but not really.
BTW, I seen a short coming in my reply for the roller animation. It mainly has to due with accuracy when it comes to the size of the ‘driven’ rollers - if the ‘Drive’ roller is X units and the ‘Driven’ rollers are half that size, they would turn at twice the driven speed - the ‘Copy Rotation’ can’t increase the speed so a “DRIVER” would have to be used, I don’t know if that will export to Unity. --sorry for that. You may have to animate one of the ‘driven’ rollers and give the rest a ‘c/r’ const targeting it. THANX

Luckily for these specific sets of rollers they are all within a small tolerance of each other. No difference really in terms of rotation speed across all the rollers.

Yeah that sounds really similar to some Tank Tread tutorials I have been watching, I’ll be messing around with that a bit more, shouldn’t have any trouble with matching the drive roller speed.

Most of the rollers (beyond the three that I sent over in a picture) are running in a Clockwise Rotation, there were 3 sets that had a Counter Clockwise Rotation and inverting the Rotation Constraint was no problem.

As far as everything located on the underside of the conveyor, creating the ‘Curve’, Mesh Obejct/Array & Curve Mod, then animation should be no problem…….BUT

Add in a troughing rollers to the top side…Will tackle that when I get the belt, at a minimum, rotating around everything down.



How would you export that Conveyor Belt as an FBX File to include that animation?


Hey, I wish I could say, but I am unfamiliar with any of that, google it I guess, sorry

maybe this video could help

I found some Tutorials on youtube with a couple different approaches, some Baking Animations, other parenting to an empty and animating the empty on the X-Axis. I have not watched the one you shared so will definitely do that. Thanks for the help!

Sure thing, don’t forget about the Unity forum, it may be of great help