The Biped System

The Biped system is a full skeleton, complete with hierarchical linkages and its own blend of forward and inverse kinematics. It is completely adjustable to your character. It will render, but you turn off its display before rendering your scene. You create a biped by going to Create tab Ø Systems, clicking the Biped button, and dragging out a biped in the viewport.

	WARNING You have to drag out the size of the biped in the viewport. If you just click once, you will create a microscopic biped.

You edit the biped and access the various modes of Character Studio under the Motion tab. In the Structure section of the tab, you set the number of links you want for the different parts of the body. The most important part of the biped is the center of mass in the middle of the pelvis, because all the other parts are linked under that. This is the part that is named Bip01 as a default. You can rename the biped and all its respective parts by changing this root name in the Structure section, rather than having to rename every part of the body separately.

Figure Mode

Figure mode is for adjusting the parts of the biped to fit your character. It’s best to get this just the way you want it before starting to animate. It’s possible to make adjustments afterwards, but the results aren’t always reliable.

With any part of the biped selected, click the Figure mode button, move the center of mass to adjust the overall position of the biped, and then start scaling the corresponding parts of the biped to fit the segments or areas of the mesh that they will affect.

	TIP Using non-uniform scale is not problematic when scaling biped parts.

You can add a “ponytail,” one of the optional body parts on a biped, with sufficient links—like the joints of a finger—to animate things like ears, noses, or hats and other clothing. For a segmented model, you can simply link the parts directly to the corresponding parts of the biped. For a single mesh, you will also have to apply the Physique modifier, as explained later.

Footsteps Mode

	Footsteps mode takes care of all the cases where you want the character’s feet to be touching the ground: walking, running, or jumping. This has always been a challenging part of character animation: preventing the feet from going through the floor. With Footsteps, it’s taken care of for you. Default footsteps, however, do not make for interesting animation. You start with the footsteps, adjust the weight and stride for your character, and add the motions that make your character distinctive.
	To create footsteps, click the Footsteps Mode button and then click Create Footsteps or Create Multiple Footsteps under the Footstep Creation section. If you click Create Footsteps, you can click in the viewport to drop the footsteps. If you click Create Multiple Footsteps, you will get a dialog box that will allow you to choose the number and attributes of the footsteps.
	Before the biped will use these footsteps, you need to click Create Keys for Inactive Footsteps in the Footstep Operations dialog box. Then you can play the animation.
	Any frame in which a foot is not touching the ground is available for free-form animation. You can go out of Footsteps mode, move the biped around, and click the Set Key button under the Keyframing section.

Loading Figure and Motion Files

A great feature unique to Character Studio is that you can save figure files (.fig) independently of motion files (such as .bip) and apply the same motion to different characters. The Save File and Load File buttons are available in Figure mode for saving figure files and in Footstep mode and free-form mode (with none of the mode buttons on) for saving motion files.

Motion Flow Mode

In Motion Flow mode, you can combine your own saved segments of animation with motion capture segments (such as those shipped with MAX R3) into a unique script. You can then export this script as a .bip file, load it, and edit it some more.

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