LEGO® Galloping Horse by JK Brickworks – Maya 2020.2 – Redshift 3.0.21

This brilliant LEGO® Technic MOC designed by Jason Allemann aka JK Brickworks is a real rigging challenge. What looks simple at the first glance has some technical finesse what makes it hard to rig the kintetic mechanics perfectly.

There's a crank controlling a bunch of gears. Two of the top gears driving the legs. All legs have a same construction concept and a fixed axis at the horse's body. The left back leg is also driving a handle what controls the waving movement of the body.

And here comes a kind of loop. The leg drives the waving but the waving body drives the legs and gears again. This will cause some issues and you need deeper knowledge about rigging techniques or you must find creative workarounds. If you look closer to the model you will recognize one strange behavior of a black vertical part at the right side what seems to follow delayed to the movement. This is wrong because the part is connected to the body but also connected to the handle controlling the body.

What you don't see due to the fast movement of the motion blurred legs that one special part is intersecting with other parts. This happens because the rig made of joints and constrains can't consider real collisions of elements forcing the construction to rotate around the axis at this moment. I tried to use a so called "Driven Key" method but this doesn't work because in reality the model has more flexibilty by real life physics what can deal with some kind of pressure.

What's also tricky is the gear construction inside the horse what will be waved forth and back and has to be considered in so called expressions controlling everything by just one animation of the crank.