Analytical inverse kinematics with body posture control

This paper presents a novel whole‐body analytical inverse kinematics (IK) method integrating collision avoidance and customizable body control for animating reaching tasks in real‐time. Whole‐body control is achieved with the interpolation of pre‐designed key body postures, which are organized as a function of the direction to the goal to be reached. Arm postures are computed by the analytical IK solution for human‐like arms and legs, extended with a new simple search method for achieving postures avoiding joint limits and collisions. In addition, a new IK resolution is presented that directly solves for joints parameterized in the swing‐and‐twist decomposition. The overall method is simple to implement, fast, and accurate, and therefore suitable for interactive applications controlling the hands of characters. The source code of the IK implementation is provided.