Puppets

Having spent several years building and animating both stop-motion and CG puppets I can honestly say that not all characters are created equally. With today's software the same character model can be set up many different ways but, only a few will be useful to the animator. I've made a lot of mistakes and learned a lot of lessons the hard way when it comes to creating puppets for animation, so here are a few of the pitfalls to avoid and tricks to learn that will make your job as an animator, a lot more fun.

One of the most basic rules of character animation is that great animation doesn't happen FROM point A to point B, It happens AT point A and point B (meaning the key POSES and anticipation and overshoot are where the good stuff is really going to happen). Some important things to keep in mind when creating a pose-able puppet for the animator are:

1. A method to control knee direction independently of the foot and hips.

2. Feet should be able to rotate 180 degrees in opposing directions.

3. A method to rotate the heel independently from the leg.

4. A method to rotate the ball of the foot.

5. A method to rotate the toes independently of the foot.

6. A method to tilt the hips side to side without having to re-adjust the torso.

7. A method to tilt or rotate the upper torso and neck without having to re-adjust the head.

3. The right hand should be able to easily touch the left shoulder without shoulder creasing and vice versa.

8. Both hands should be able to easily touch the top of the head without shoulder creasing.

7. A method to twist the forearm.

9. A method to control elbow direction independently from the shoulder and wrist.

10. A method to place to hand on a surface and lock it there.

11. A method to slide a hand across a surface.

12. A method to control the arc line of action of the hand separately from the body.

Another important thing to keep in mind is that automating actions, (i.e.... Hip placement, toe, heel roll) will often result in fighting with the puppet instead of posing it how you wish. Exceptions to this are situations where it will help you POSE the character quickly (i.e.. a slider for rotating all the fingers into a fist for example). Automated actions sound great on paper and look great when your moving a character around to test the puppet but, when it comes time to animate they usually get in the way. When I'm posing a character and I move one of the feet, that doesn't mean I want the hips to move or the other foot to rotate. I'm going to keyframe those motions anyway so let me do my job.

I've seen many experienced animators struggle with a puppet because it wasn't set-up properly (I'm one of them). It seems that many technical directors have been told that setting up a simple, easy to use character, means automating many of the controls so the animators don't have to waste their time looking at extra tracks. THIS IS COMPLETELY FALSE. A simple, easy to use character is one that is easy to POSE and, doesn't fall apart between POSES. Anyone who tells you otherwise probably has very little experience animating stop-mo or CG puppets. It's important to realize that computers, expressions, math and the most sophisticated algorithms can't produce great character animation. It's the artist using the the computer that creates a great performance. Character animation on a computer is exactly the same as character animation with cels or Stop-motion animation with puppets. Let the animators decide how the characters should move.

Another important factor in character setups is making the system easy to read and understand. Bones and control nodes should be easy to see and select. Also, the animator should be able to read what the characters skeleton is doing at a glance. I shouldn't have to guess or select a node to see its orientation. Believe it or not, this is a very important issue in many off the shelf software packages.

The points I'm trying to make here are:

1. Provide yourself with a puppet that is easy to pose.

2. Give yourself a puppet that's easy to read, understand, and FUN to work with.

Here's a few tips for creating your own puppet that's easy to work with.

1. The hands, instead of animating each joint in the hand separately, create one control or slider to bend each finger. Or better yet, create a system that allows you to capture a hand gesture for later use.

2. The arms, using forward kinematics is a simple approach that gets the job done and provides most of the functionally needed in this area. However, it won't allow you to lock a characters hand to an object. If your software has a good IK system and you need your characters arms to stay locked in place, take advantage of it.

3. The torso, again FK. Does every thing you NEED it to do. This is one area that probably shouldn't be automated.

4. The head should rotate independently from the neck. There are two reasons for this. First, if I want my character to stare at something while he's moving I don't want to constantly have to readjust the head. The second goes back to the traditional principles of animation:

----Overlapping action and Progressively breaking joints

Generally in a head turn, the head will either lead the action or follow the action like a whip. Also the head should generally follow a slightly different arc than the neck. Head turns and eye blinks are one of the most important elements used to convey character and produce the illusion of life.

Best solution: Use the skeletons root orientation in world space to orient the head

5. Collar bones, believe it or not this is something that a lot of people overlook. Ever try to raise you hands above your head without using your collar bones and shoulder blades. It doesn't work. Make sure you've got a way to shrug the shoulders and raise those arms up high.

7. The knees, there has to be a method to control knee direction independently of the hips and feet or this entire area will be very difficult to work with. If you can't control where the knees are pointing, how do you pose the character?

8. The feet, this is a very important area of your puppet, after all, if your using IK to control the lower body of your puppet this area is going to drive most of that action. There are two different schools of thought regarding setting up the feet. Working from the heel of the foot and working from the ball of the foot. I prefer to work from the ball of the foot for a couple of reasons.

a. Your character is going to need to pivot on their toes from time to time. If your working from the heel this is going to be hard to do and may look odd.

b. Your going to want your character to spring off the ball of their foot a lot. Have you ever tried to jump or walk with out pushing off with your toes?

c. Try climbing up a ladder or walking up stairs on your heels and see how far you get.

d. How many times have you reached for something up high with out standing on the ball out your foot?

e. Balance, try balancing yourself on the ball of one foot, then try balancing on the heel of one foot, which is easier?

Regardless of which school of thought you choose to work with here. Give your self a method of rotating your puppets foot at the ball and the heel. I.e... If you work from the heel, make sure you can still get your character up on their toes. If you work from the ball, make sure you can easily get your character to rock back on their heels for those strong heel strike poses.

For a diagram of how I set my feet up, go here.