One of the characteristics you see, and many people have it including great scientists, is that usually when they were young they had independent thoughts and had the courage to pursue them.

-Richard Hamming "You and your Research"

Natural Character Posing from a Large Motion Database   Project webpage 

We present NAT-IK, a new interactive inverse kinematics scheme that can robustly and interactively generate natural poses in a large human-reachable space. NAT-IK employs an adaptive kd-clustering algorithm to select a representative frame set from a large motiondatabase, and a sparse approximation algorithm to accelerate thetraining and posing speeds. The model training process needsto be done only once. The training results contain 30MB of data, which can beconveniently imported into existing animation packages. To appear in IEEE Computer Graphics and Applications.

Motion Compression using Principal Geodesics Analysis    Project webpage [Tech Report]

We present a novel  compression method for human motion data using PGA (Principle Geostatic Analysis). Our method reaches high compression ratios (>60:1) while maintaining good reconstruction quality. Presented at Eurographics 2009 (Best paper award).

 DL-STDM: A Robust Watermarking Scheme for Motion Data

We propose a double-layer STDM watermarking framework and verify it on 1000 motion clips. Experimental results demonstrate that it is more robust than existing methods, including Kim's method and standard STDM. 

[PDF(Computers & Graphics, 32(3), pp 320-329, 2008)         


A 12-DOF Analytic Inverse Kinematics Solver for Human Motion Control

One of the fastest IK solver for 12-DOF chain of human-like figure. It provides closed-form solutions to multi-constrained IK problem. It is rather stable and easy to implement. But it only works for human-like figures.

Technical Report: [PDF]

                                            Paper Published in JOICS: [PDF]

                                            Demo: [MP4]


On-line Motion Style Transfer

The “stride” style of a walking motion (middle) was transfered to a running motion (top), producing a “stride running” motion (bottom) within 300 miliseconds.


Paper Published by Springer LNCS (ICEC '06): [PDF]

Demo: [MP4]

[ Errata]




Template-Model Based Modeling and Animation of Human Bodies with Anatomical Structure

Given a designed skin mesh, the template model consisting of bones and muscles can be semi-automatically deformed according to the shape of the mesh. This techniques can decrease the workload of animators who want to generate anatomically plausible skin deformations.


Paper presented at CASA 2005: [PDF]       

Demo: [MP4]










 State of the Art of the Research on Human-Body Modeling and Skin Deformation in Computer Animation






Paper  published in Chinese J. Image & Graphics: [PDF] (in Chinese)