  This paper proposes a shoulder inverse kinematics (IK) technique. Shoulder
complex is comprised of the sternum, clavicle, ribs, scapula, humerus, and four
joints. The shoulder complex shows specific motion pattern, such as Scapulo
humeral rhythm. As a result, if a motion of the shoulder isgenerated without
the knowledge of kinesiology, it will be seen as un-natural. The proposed
technique generates motion of the shoulder complex about the orientation of the
upper arm by interpolating the measurement data. The shoulder IK method allows
novice animators to generate natural shoulder motions easily. As a result, this
technique improves the quality of character animation.
