Adjusting Vertical Dynamics

Because Biped's keyframe interpolation is based on the mechanics of two-legged characters, it varies according to whether the feet are on or off the ground. When you activate footsteps, the default keyframes for the leg tracks are given states that correspond to the footstep pattern from which they were created.

A leg's motion has four phases, beginning with the foot on the ground. Then the foot lifts, moves through the air, and returns to the ground again. Biped divides this motion into four phases as follows:

Biped displays the state of each foot in the General rollout of the Motion panel.

Regardless of the footstep pattern, in order to properly interpolate you character's motion, Biped will always generate and maintain leg keyframes at each lift and touch transition in the steps.

Footstep states in General rollout

Dynamics of Walking

For our purposes, a walking gait is defined to be any footstep pattern in which there is always at least one foot on the ground. Of course, this is a more general use of the term since it includes many irregular and non-periodic footstep patterns, and even standing in place. The main feature of walking gaits is that there is no dynamics of ballistic motion at work.

When Biped first activates footsteps to create default keyframes for walking footstep patterns, it attempts to create as few keys as possible to establish a fundamental framework for you to work from. In general it will create: