Fast Optimization Design of the Flexure for a Space Mirror Based on Mesh Deformation

According to the requirements of high force-thermal stability and high performance of a space telescope, a space mirror assembly must not be influenced by environmental factors. In this study, a space mirror assembly under load conditions, such as gravity, thermal, and assembly error, is considered. After the mirror is optimized, the surface shape error is reduced by 22%, and the mass is increased by 0.113 kg. In order to improve the efficiency of integration optimization, we present a fast optimization method using mesh deformation to be applied to the flexure. The size parameters of flexure and axial mount position are obtained by optimization. With our method, the single optimization time reduces from 10 min to 40 s, which can improve the efficiency of multi-objective optimization. The mirror assembly is fabricated and assembled based on optimization results. Finite element analysis (FEA) and test results for the space mirror assembly confirm the validity and feasibility of the fast optimization method, and we believe that the flexure based on fast optimization meets the requirements of a space mirror assembly for space applications.

Local Dynamic Updating Method of Orebody Model Based on Mesh Reconstruction and Mesh Deformation

In this paper, to update the orebody model based on the given interpreted geological information, we present a local dynamic updating method of the orebody model that allows the interactive construction of the constraint deformation conditions and the dynamic updating of the mesh model. The rules for constructing deformation constraints based on the control polylines are discussed. Because only part of the model is updated, the updated mesh is effective and the overall quality is satisfactory. Our main contribution is that we propose a local dynamic updating method for the orebody model based on mesh reconstruction and mesh deformation. This method can automatically update a given 3D orebody model based on a set of unordered geological interpretation lines. Moreover, we implement a deformation neighborhood region search method based on the specified ring radius and a local constrained mesh deformation algorithm for the orebody model. Finally, we test the method and show the model update results with real geological datasets, which proves that this method is effective for the local updating of orebody models.

Efficient Medical Image Adaption via Axis-Aligned Mesh Deformation

Content-aware medical image adaptation can make medical images be well presented on different display devices. The existing adaption algorithms mainly consider the visual effect of salient regions, such as specific organ areas of the patient body, but either ignore the quality of unimportant areas or execute more slowly. In order to enhance the effect of adaption and accelerate the speed of adaptation, we propose an efficient medical image adaptation method via axis-aligned mesh deformation. With this method, importance map is firstly produced by combing the weighted edge map and saliency map. Then, integer programming is used to initialize and deform the axis-aligned mesh based on importance map. Finally, image adaptation is operated rapidly by bi-linear interpolation. With the proposed method, the real-time image adaptation can be realized, and not only the visual effect of the significant areas but also the contour integrity and continuity of the non significant areas can be maintained. Experiments on open data-sets show that the proposed method has high efficiency, better effect and strong stability, and is suitable for real-time image adaptation.