individuals were not aware of the appearance of their own body, they seemed to generally

respect the avatars of others, trying to avoid passing through them, and sometimes

apologizing when they did so." The avatars used in the study were simple models

associated with a unique color [18].

 Digital characters have been successfully integrated into real environments using

computer vision and camera tracking techniques. These characters are used partly as

"virtual teachers" that train factory workers to operate some of the machinery. The

virtual humans pass on knowledge to participants using an augmented reality system.

Although the characters are automated, a training specialist can control them from a

different location via a networked application [19].

 Digital character realism has been integrated into the character rendering system

created by Haptek. This system can integrate multiple highly realistic and customizable

characters into a virtual environment. These characters also act realistically (i.e. blinking,

looking around, and shifting weight). The Haptek system allows these characters to be

used as avatars, or as autonomous virtual humans [20].

 There are many other commercially available character-rendering systems:

 UGS Corp. Jack-usability, performance, and comfort evaluation using digital
 characters that are incorporated into virtual environments.

 Boston Dynamics DI-Guy-real-time human simulation used in military
 simulations created by all branches of the United States Armed Forces.

 VQ Interactive BOTizen-online customer support conducted by digital
 characters. Characters respond to queries using a text-to-speech engine [21, 22,
 23].