I. Foreword
The problem of non-rigid dynamic scene reconstruction is a current research hotspot in the field of 3D scenreconstruction. Many researchers have been active in this field, from approaches using scene-specific priors to template-based and template-free reconstruction methods under fewer constraints. The non-rigid ICP (Iterative Closest Point) algorithm [1] was originally proposed for the 2D non-rigid alignment problem and later extended to 3D non-rigid alignment [2], The first non-rigid alignment methods [3], [4] that could track complex deformations used deformation agents to decouple the dimensionality and model complexity of the decoupling optimization problem, but still required offline operation. In recent years, many robust offline template tracking methods utilize keyframes and robust optimization algorithms [5], [6] that allow for discontinuities in the deformation field and are more suitable for joint motion tracking problems.