How to rig your machine gears using constraints and one all-controlling empty

After creating ‘Pumping Memory’ a showreel of a machine I build and posted the model on blendswap I got a few requests for a tutorial on the constraints I used on the gears (links to blendswap and showreel at the bottum)

In this tutorial I will show you how to make different types of links between gears using constraints. We’ll go into the copy rotation-, and transformation constraint.
After this we’ll create a controller object to control your entire machine and make it really easy to control and animate. I will also show you how to create a cyclic never-ending animation using the cycles modifier and the graph-editor.

showreel of the original machine:

Blendswap for the machine:

WOW – an awesome model and now an awesome tutorial. Thanks!!

i have been trying to animate a pump similar to the one you have in the back there. how is that done? my final model ended up with an IK rig for the rotation side and a track to constraint tracking an empty parented to a bone that follows the pumping motion of the boom, but even that causes the pump rod to twist. every other constraint/rig system i tried just destroys the model. any chance you could show us how the pump itself is rigged?

@ Safetyman: You are very welcome :wink:
@ Small Troll: I will see what I can do, I’ve got a relitivly short day of school tomorrow, so depending on the amount of homework given I’ll try to squize out enough time to tape a quick tut on the oil pump :slight_smile:
Offcourse you can try to reverse-engineer the model I shared on Blendswap. Again, I’ll see what I can do :smiley:
If I am unable to make this tutorial on short notice I’ll put a post on this thread within 48 hours from now.

I don’t know how Ristridyn rigged it, but it’s basically just a crank and piston with the rod broken into two parts by the beam.

In the armature depicted above, Beam and CrankRod are an IK chain of length 2 targeting Crank; PistonIK is a child of Beam; Stroke, Piston and PistonRod are an IK chain of length 3 targeting PistonIK, with Stroke allowed to stretch but not rotate, PistonRod to rotate but not stretch, and Piston neither. When Crank is rotated around its tip (the cursor location in the picture), Piston moves up and down.

Real beam engines have rather more complex linkages between the piston rod and the beam, to keep the rod as close to vertical as practicable.

Best wishes,

@ Mccollet, Thanks for helping out here, this is indeed a rig similar to what I used, though I side less bones and more constraints.
But this one will work perfectly as well. thanks for the comment :smiley:

hmm interesting. this is identical to the rig i originally started out with btu for some reason it caused problems. if i remember right the beam wouldnt rotate, it just followed the ik wierdly. the whole beam went up and down rather than pivoting

I did the extra tutorial for you :slight_smile:

cool! thats really helpful. Do you mind if I link to these videos from my youtube channel?

Looks like super complicatedly awesomeness. Will be watching.

Thanks :smiley: @Small Troll: Sure not a problem :slight_smile: