Combining analytical inverse kinematics with example postures to generate virtual human whole body reaching postures

To ensure the real-time interactivity and the lifelikeness, analytical inverse kinematics and the example posture library are adopted to generate whole body reaching postures. The upper limb joint angles are solved using analytical inverse kinematics and optimization. First, a new objective function to minimize the wrist joint angles is presented and the optimized swivel angel is calculated with directed searching method. Afterwards, the other joint angles in the upper limb are calculated by analytical IK and bidirectional searching with joint limits and collision avoidance considered. A new example key postures sampling and design principle based on the vertical height of the shoulder joint is presented and example whole body postures except upper limb joints are pre-designed by hand off-line. Once the reaching target is given, the corresponding posture in the library can be determined efficiently using related shoulder joint height values. Finally, through the combination of the example posture found in the library with the upper limb joint angles calculated by analytical IK, the whole body reaching posture from vertical standing to total squat is generated. The main advantage of the whole process is its high speed and practicability and therefore suitable for interactive applications.