Hydraulics

One of the important parts for Albus movements were the hydraulic pistons included in both legs and arm.
The idea is that despite his movements, for cartoonish as they might be, they needed to be constrained to each other at all time to keep this feeling of being a mechanic character. Matt gave me a good idea to aim constrain them one another and, on its own, it was working just fine. The problem came when I had to constrain those constrains to parts of geometry that where already bond to the rig.

I found this very useful video online that basically takes you through a good way of not only make functional pistons, but also how to "cheat" by making an infinite constrain between the master and slave parts of the hydraulic part.

Skeleton of Albus

Rigging was not such a bit task as the robot had a simple structure, but the problem began when I had to bind it to the geometry.
I was told to try a rigid binding as it could work best for robot like movements, but no matter how much I tried I just couldn't get my head around it.
I ended up going for a soft binding and it turned out to be just fine, as I just had to do be very specific with the weight painting to avoid having organic movements.
Probably the part that made it a bit difficult was the fact that the character was not model in a T pose so the influence between the joint in the arm and right leg was creating a bit of confusion, but the character doesn't have a full arm extended so not putting him on a T pose from the beginning was part of the plan.

After weight painting, the joints were working smoothly but I discovered that there were some issues when the elbow would bend above one point. By the time I realised this issue the project was ready to start animation and going back to fix this small issue was probably going to delay the whole process. We opted to just make a note next to the model to let them know where to be careful in case someone else was to work with it in the animation process. Luckily, the movements of Albus did not require to bend his elbow to that extend.

Skeleton and skin of an alien

So this is the part of the process that was the most complicated for me in an over all view. From the beginning having to think where the joints go sounds easy as we can reflect the joints that we have, but it is pretty easy to over look at some other movements that normally I wouldn't even consider as important (for arm roll and the clavicles for example).
At some point here I got left behind from the rest of the class as I understood something completely different in one lecture. Luckily I was able to catch up thanks to the video guides we had made.

After making the skeleton, we had to constrain them one another, think of a hierarchy in which the react in relation to the whole structure and identify key joints for certain movements. All this at the same time as making sure that everything was properly named and organized as any mistake at this point would be pretty dramatic and complicated to come back later on to fix it. After the joints where orient and parent constrained, we then moved to create some controllers or handles to avoid having to move the skeleton itself. Master control, jaw and a large number of NURBs circles where created and placed on position, making sure the pivot points were set on the appropriate joint.

The whole process itself was pretty intimidating, specially for the amount of detail that you have to put on. Also knowing that the next step was skin weight painting and that if anything was wrong with the rig, the only way to come back and fix it is to delete all work done in the weight skin process; now that put a lot of pressure to make everything right on the first go.

So after soft binding the skin to the rig, the big job of weight paint the skin come into place. This is basically to determine  how much influence each joint has over each vertex of the character. So it is a case of try and test; paint a bit, bend, see how react and modify according to the elasticity of the skin in relation of the deformation desire when animating. Long story short, it is hard work, and from this depends a lot of the final look of the character. This is why, after doing a big work on the weight skin painting it's really painful to find a problem with the rig that will cause you to unbind the skin, fix the skeleton, then bind it again and repeat the long process.