Eurhythmy: Concept and process

Eurhytbmy means a state of harmony between body and mind. Reflecting this theme, the animation depicts animals, humans and a flock of birds joining together in a surrealistic spiritual dance in a deserted temple courtyard. Adding a sense of religious mystery to the surroundings, the temple, bearing a resemblance to an Islamic mosque, is decorated with symbols from other religions: Egyptian hieroglyphics adorn the walls, and images of angels grace the inside of the temple dome. The observer enters the temple, watches and then becomes part of a ritual dance, one that expresses a mystifving harmony between the physical and spiritual world. The religious symbols within the architecture might be viewed as symbols ofinstitutionalized religion, where human existence is conceived in terms of a soul which transcends the physical self and the real world. In contrast, the spirituality evoked in primitive dance is acted out in reverence for our identity with ourselves as animals, deeply rooted in our bodies and our connection with the natural environment. To convey a spiritually uplifting dance, the movement of all of the animals had to be both convincing and expressive. As graduate students at Ohio State University, Michael Girard and Susan Amkraut each carried out research focused on the development of computational models which embody physically motivated qualities of complex animal movements. The animation in Eurhythmy was produced exclusively with the software developed during this research. The human and animal motion was produced using the PODA animation system, written by Michael Girard. PODA implements Girard’s research on modelling legged animal motion, incorporating many robotics techniques for body co-ordination, limb kinematics and dynamics. The multi-legged locomotion of gaits and dance seen in Eurhjthqr employs inversekinematic control of limbs in order to achieve goal-directed leg motions. A supervisory level of control over legged animal locomotion is provided by the animation system. Given the animator’s specification of a sequence of gaits and a desired path of motion in the horizontal plane, the locomotion model calculates the co-ordination of the animal’s legs in each gait, manages transitions between gaits and determines footholds which are computed to bring each of the legs to a dynamically stable supporting position (see Figure 1). The translational motion of the animal’s centre of mass is accurately simulated during the animal’s flight phase as a function of the velocity of the animal’s centre of mass at the time of lift-off and the downward gravitational acceleration. Also, the animal’s banking angle as it turns is calculated to maintain the Eurhythmy: Concept and Process