The 3D capability map model of humanoid robot based on 3D point cloud data has the disadvantage of large voxel mesh searching computation. Considering the hierarchical advantage of OcTree in 3D space subdivision, a local environment and capability map model based on Octomap was proposed. Firstly, a binary-tree-like kinematics model of NAO humanoid robot was constructed according to the joint composition, forward kinematics, inverse kinematics and rigid body coordinate transformation of NAO robot. Secondly, the forward kinematics was used to calculate the 3D discrete reachable point clouds in Cartesian space, which were used as the basic workspace of the robot terminal effector. Thirdly, the methods of transforming the point cloud space representation into Octomap space node representation, especially the probability updating method of space node, were described emphatically. Finally, an optimization method of space node updating order selection was proposed according to the geometric relationship of nodes. With this optimization method, the space optimization representation of the humanoid robot's capability map was realized efficiently. Experimental results show that compared with the original Octomap updating method, the proposed algorithm can reduce the number of space nodes by nearly 30% and improve the computional efficiency.

Color space conversion is the key technology in color management,direct quality-detection of printing images and color separation. Therefore, it is very important to find out a accurate and practical transform from CMYK to L*a*b*. In this paper the dot colorimetric plane of four-color halftone printing based on optic phenomena was verified by the standard printing. Then the equation of transition from CMYK to L*a*b* was modeled by analyzing the colorimetric values of process printing patches based on mathematic statistical method and numerical analysis method. And its precision was discussed and the main reasons that influence the equation precision were analyzed.