Domarius's animation tips
Reference material
If possible, film yourself or someone else going through a few variations of the animation you want (exaggerated, minimalistic, theatric...) and if it's a complex motion, you may want to capture each example from a few angles. If you can't film your own footage, act it out in front of a mirror, paying particular attention to the small sub movements.
Actually I really can't stress how good it is to have reference footage. Even if you just do a rough job of the overall movement, adding in the little sub movements that you can pick up from playing the footage over and over (arms swaying due to torso movement, shifts of the legs or arms to maintain balance, etc) the "believability" of the animation will increase ten fold. The viewer's brain will pick up on these "physics" cues and tell them the animation is "real".
Rough out key poses
Rough out the key poses in your animation program. To get the timing right, play the empty anim, and stop it where you think the peak of the first pose should happen, and create it there. Continue on for each major pose. Fully pose the body as much as possible, sometimes it can be hard to come back and make major changes to the pose when there are already a lot of other little movments in there, but at least if you are using Motion Builder, you can make a new layer and adjust the overall pose that way (see the Motion Builder tutorial).
Changing position
Whenever the center of mass changes and the character moves its feet to another position to maintain balance, the feet must reach their destination before their center of mass reaches the end of its movement. Because the feet is what causes the center of mass to slow and then stop moving.
Humanise the movement
Less consistant transitions
"Humanize" the overall movement with this technique - consider the transition from one pose to another, it takes 2 key frames (for each body part - but if you select all body parts in Motion Builder, you can do the following as if it were just two keyframes for the whole body).
- Add a keyframe just after the first keyframe, and drag that forward to some point less than halfway between the first and last.
- Add a key frame just before the last keyframe and drag that backward to some point more than halfway between the first and last.
This makes for a slow suble movement at the start, and then a sharper transition into the final position, and then a small wobble as they hold the position. First big step to making it look less robotic.
Break up the perfect timings
Randomly adjust the timing of starts and ends of movements of each body part so that different movements are not starting and stopping at the same times at each other. Start random, and then use your artistic eye to tweak it.
Subtle movements
Apply the more subtle movements, such as "secondary" movements - other indirect movements caused by the main action (eg. arms swinging gently). Refer to the original footage for this. If you have used the mirror, go back and do the action again and this time look for the subtle movements.