Recently someone on eurobricks was attempting this. Right now, they're experimenting with a deform-able mesh, which is what the lego video games use.
More here http://www.eurobricks.com/forum/index.php?showtopic=113184

Hello,

Unfortunately I don't really have any experience with rigging. The difficulty is that you might need higher poly mesh to get a proper result. A couple of weeks ago, Nachapon made some experiments. He posted this image:

He also posted a couple of links in the comments: http://www.mecabricks.com/en/models/kLyjWOQ3jJr

Thanks guys. I think I will add some subdivisions and clean up the geometry.

Let us know how you progress. I'm sure quite a few people would be interested 😃

Personally I prefer the style of the LEGO MOVIE. Keep them as they are with little tolerances for a good stop motion style. I have to say that ANIMAL LOGIC did a perfect job. This will keep things simple and give you less headache. Honestly: the animation style of the LEGO MOVIE is a blast to watch.

In 3d character development you have several steps to do that finally an animator is able just to focus on a simple setup for his animation task. If you want to bend the model you have to subdivide the parts for a nice subdivsion surface result and you will use a bone rig with a proper weight setup. But most important is that the rig will be controlled by handles. That means you use simple spline elements which are connected mostly by scripts to the parts which allows you an easy and error free control for the animation.

Here are some examples how this will look like:
https://www.youtube.com/watch?v=51qUyH7h6ss
http://www.cgmeetup.net/home/making-of-the-lego-movie/

Especially for very complex setups a clever and simple rig controlled by handles is essential. Finally a pipeline will use proxy-models for animation. These models are very simple low-poly-versions of the final render models for best performance. They usually behave the same good enough for capturing without shaders but textures like facial expressions. Also for facial animations you need a clever and flexible setup like what you can see in the Making-of-link of the LEGO MOVIE. ANIMAL LOGIC is using a separate face rig which will control spline based textures internally mapped onto the head. The face rig is usually present in a separate window. Finally when the animation is finished they replace everything with the final elements with all shaders and other details for lighting and rendering.

The people doing such tasks are called "Character TD" (Technical Director). They are usually 3D-artists with a strong background in programming (Python, C++ etc.) like SCUBS. 😃

Let's animate bricks!
Scrubs: do you want to be our strong programmer? 😛

It looks like it is the next step. We've been building and rendering fix images. Next: animation
Another field were my knowledge is quite limited and even nonexistent lol
The LEGO Movie style with no parts deformation seems to be easier to start.

I agree with virtualrepublic, too 😉

For a Minifig-Rig you don't need programming skills. Just some knowledge about techniques how to rig a character. We are talking about translations and rotations only but it would be wise to script some "special effects" like when rotating an arm in z-axis where you have to pull it out to the side a bit to prevent intersections. There are many ideas how to simplify special movements which would need a lot of animation keys and curves to deal with just by a single handle. A good rig will just allow you to select the handles only. I guess there are tutorials for Blender describing basic techniques. Finally you can load example scenes to analyze. And last but not least the LEGO figures are quite simple compared to PIXAR characters 😃

I Just made a post with a download link to my rig.

http://mecabricks.com/en/forum/topic/351

use the epicfigrig https://www.youtube.com/watch?v=mZM0jk-jfP0&list=TLPQMTUwNjIwMjHEef4lgEcVWg 😃