rig


CGI coffee

Dynamic sloshing liquid rig. Making it look like a simulation with nothing but the Awesome Power of MATH. Part 1: the basic rig

Check this out:

Looks delicious, doesn't it?

What you see here is not a result of a fluid simulation. It's a combination of Linear Algebra and some neat mesh manipulation tricks to make the surface deform and behave as if it were a small body of water in a container reacting to being thrown around a scene, sloshing and splashing back and fourth.

This is what you call a rig. A "sloshing liquid rig" as I decided to name it. Intended to be used in a couple of scenes of the animated short film I'm working on.

final-liquid-rig-v2

This bad boy will save me so much time when I get to animating liquids for background objects.

Let's now dive in and see what's happening under the hood. There's some math involved, but be not afraid: as always, I will try to make it as entertaining as possible and visualize everything along the way.

Quick review and test of the Perception Neuron Lite MoCap system

Noitom is a company who specialize in affordable inertial motion capture devices and software, specifically their own line of MoCap systems called Perception Neuron.

Yesterday I finally received my Perception Neuron Lite kit which is a promotional 6-neuron system for those who want to interact with 3D objects in a virtual reality headset or are just looking to try out Perception Neuron before investing into a 18- or 32-neuron kits. I was interested in Noitom tech since the first days they started their Kickstarter campaign back in 2014, so it's only natural I jumped the bandwagon as soon as the opportunity presented itself.

This is what arrived with the order and what I'll briefly review:

perception neuron lite box

Perception Neuron Lite carrying case

perception neuron lite case contents

Perception Neuron Lite carrying case contents

It's important to remember that this is an inertial MoCap system, which means it comes with extremely sensitive sensors which only work in a relatively magnetically safe environment. They are so sensitive in fact, that they come in a special anti-mag container. After use they should always reside inside to make sure they don't magnetize which would render them useless.

Perception Neuron Lite Anti-Mag Container

Perception Neuron Lite Anti-Mag Container

Having said that I must admit that I had no issues whatsoever using them even in close proximity to a monitor screen, PC and even my Wi-Fi router. There's also a crazy amount of Wi-Fi networks available all around the apartment so all I can say is – the system worked like a charm even in such non-perfect conditions which was a very pleasant surprise!

Perception Neuron Lite photo

Perception Neuron... well, neurons

Setting the whole thing up was quite intuitive, although I found the manual quite lacking in detail on how to assemble the cables and put it all together. Just a Quick Start Guide and you're kind of on your own.

Perception Neuron Lite photo

Perception Neuron Lite strapped to my quaggy arm

Perception Neuron Lite photo

The whole set-up is lightweight and durable

This particular kit doesn't come with a standard glove but rather some sort of a Velcro strap you wrap around your wrist whilst securing it with your thumb. In fact all non-electric elements or connectors have Velcro strips for placing on top of the base elements.

Perception Neuron Lite close-up photo

There's also a semi-interactive manual provided with the Axis Neuron software, but it mostly explains how the system works. Axis Neuron is a specialized app by Noitom designed to record and playback the MoCap data from the Perception Neuron system and it works quite well!

Axis Neuron Software

Axis Neuron Software

There are two editions: Standard and Pro, the latter costing about 700$ but (in theory) available for free for all Perception Neuron owners. I've contacted support on how to obtain access to the Pro version since it has all bells and whistles including motion smoothing, contact editing and other tools the Standard version is lacking.

UPDATE: Noitom support team replied the very next day with the info on how to receive my copy of Axis Neuron Pro, so now I'm a happy Pro user. Thank you, guys!

After quick set-up and calibration I was actually able to produce a descent take. Here's the raw recording without any smoothing or filtering to showcase what PN is capable of:

All in all, I can definetely say that the system works and can process even relatively fast motion. It will surely come in handy when the time comes to animate the characters in the film, so my next purchase from Noitom will be the 32-neuron full-body MoCap set. Can't wait!