The Angry Man (Mocap editing) by Yue Peng Toh

[ Download (.wmv) ] [ Youtube ] Goals The goal is to create an animation of an angry walking man from the mocap data of a normal walking man. At the end of the angry walk, he will exhibit a (unexpected) high kick to show how furious he is.

Techniques/Methods

1. Increase movement speed To convey the emotion of anger, the man must walk fast. In fact, he has to look like he is charging. Hence, I increased the walking speed of the original man by taking out all the even-numbered frames. This effectively doubles the speed of the walking man, and adds the charging effect. 2. Exaggerate arm swing An angry person swings his/her arms through a larger angle both to the front and to the back of the body. I increased these angles to achieve this effect. I did this by multiplying the original forward/backward angles between the upper arm and the body by a constant factor of 2.5. Forearms are also bent to almost 90 degrees with respect to the upper arm. The resulting arm posture in general makes the man look like he is on the brink of running, as he storms towards his adversary. 3. Clench the fists Clenching is an important action associated with anger because not only does it portray the tensed-up state of the body, it is also the action adopted before you punch someone. The fingers are altered to bend inwards while the thumb is flushed down, touching the fingers. The man maintains this state throughout the angry walk. 4. Lean forward, tilt head upwards The upper body is thrusted forward to convey menace and anger. It also portrays speed. I raised the head up a little so that the man knows where he is heading. He should know where he is heading! He is a man on a mission:p

Arm swing exaggerated, fist clenched, forward leaning, head up, and moving at high speed. Angry eh?

5. The final kick To add the final kicking motion, I added 4 main "keyframes" after the last frame of angry walk: halfway, up, halfway, down. The first keyframe depicts the state where his knee is still bent and his upper leg has not full extended. The second keyframe is when the leg have kicked out to the highest point. At this point the foot also bends down to the fullest possible too. The third keyframe is similar to the second keyframe. Finally, the last keyframe is his "landing position", with the kicking foot in front. Note that during the kicking motion, the man is made to lean backwards. This is important because it looks more natural to lower or back off a bit when u kick forward. Also, the "halfway" stage is neccesary because I want the kicking leg to bend first before kicking up, rather than swing a straight leg up which could look awkward. To piece the actions of the keyframes smoothly, I linear-interpolated the bone angles so that frames in between can be generated.
Halfway	Up	Down

Results The final product is a 3 second angry-walking-man motion. I am satisfied with the exaggerated arm movements because they play a huge role in changing a normal walk into an angry walk. Even though the transition between the walk and the kick is slighly fast, I think it contributes to the sense of "cartoon element" that this walking man already shows through his exaggerated walking action. The height of the kick also adds to the sense of unexpectedness which I have wanted to achieve. Some Observations Motion-captured animations give realistic human-like results since they are captured from the actions of humans themselves. Hence, mocap is especially good for purposes where we want to achieve a huge degree of realism in our motions.However, these animations might be harder to edit too because changes made must maintain and not break the existing realism in the animation. Hand Drawing Animations on the other hand, are usually geared towards cartoon-like productions. Editing rules tend to be more flexible, and many "non-realistic" techniques, like breaking the body parts, stretching, exaggeration are used to good effect in portraying various feelings, personalities, emotions or states. In the production of the "angry man", I used exaggeration in mocap editing, and the results are resonably great. This shows that there are no hard-and-fast rules to editing animations as long as the output conveys the intended emotion you set out to achieve.