In this paper,we discuss a new multilevel method for the vascular surface registration.Such registration is used for hemodynamic calculations.Special care is given to the discretization of the distance function and re...In this paper,we discuss a new multilevel method for the vascular surface registration.Such registration is used for hemodynamic calculations.Special care is given to the discretization of the distance function and regularizer,as well as to the surface coarsening.We demonstrate the effectiveness of our method of vascular data used in flow computations.展开更多
In order to obtain and master the surface thermal deformation of paraboloid antennas,a fast iterative closest point( FICP) algorithm based on design coordinate guidance is proposed,which can satisfy the demands of rap...In order to obtain and master the surface thermal deformation of paraboloid antennas,a fast iterative closest point( FICP) algorithm based on design coordinate guidance is proposed,which can satisfy the demands of rapid detection for surface thermal deformation. Firstly,the basic principle of the ICP algorithm for registration of a free surface is given,and the shortcomings of the ICP algorithm in the registration of surface are analysed,such as its complex computation,long calculation time,low efficiency,and relatively strict initial registration position. Then an improved FICP algorithm based on design coordinate guidance is proposed. Finally,the FICP algorithm is applied to the fast registration test for the surface thermal deformation of a paraboloid antenna. Results indicate that the approach offers better performance with regard to fast surface registration and the algorithm is more simple,efficient,and easily realized in practical engineering application.展开更多
Surface registration brings multiple scans into a common coordinate system by aligning their overlapping components. This can be achieved by finding a few pairs of matched points on different scans using local shape d...Surface registration brings multiple scans into a common coordinate system by aligning their overlapping components. This can be achieved by finding a few pairs of matched points on different scans using local shape descriptors and employing the matches to compute transformations to produce the alignment. By defining a unique local reference frame(LRF) and attaching an LRF to shape descriptors,the transformation can be computed using only one match based on aligning the LRFs. This paper proposes a local voxelizer descriptor,and the key ideas are to define a unique LRF using the support around a basis point,to perform voxelization for the local shape within a cubical volume aligned with the LRF,and to concatenate local features extracted from each voxel to construct the descriptor. An automatic rigid registration approach is given based on the local voxelizer and an expanding strategy that merges descriptor representations of aligned scans. Experiments show that our registration approach allows the acquisition of 3D models of various objects,and that the local voxelizer is robust to mesh noise and varying mesh resolution,in comparison to two state-of-the-art shape descriptors.展开更多
This paper proposes a novel method to compute the diffeomorphic registration of 3D surfaces with point and curve feature landmarks.First the surfaces are mapped to the canonical domain by a curve constrained harmonicm...This paper proposes a novel method to compute the diffeomorphic registration of 3D surfaces with point and curve feature landmarks.First the surfaces are mapped to the canonical domain by a curve constrained harmonicmap,where the landmark curves are straightened to line segments and their positions and inclining angles are determined intrinsically by the surface geometry and its curve landmarks.Then,the canonical domains are registered by aligning the corresponding point and straight line segments using the dynamic quasiconformal map(DQCM),which introduces the combinatorial diagonal switches to the quasiconformal optimization such that the resultant map is diffeomorphic.The end points of the source curve landmarks are mapped to their corresponding points on the target surface,while the interior points of the source curves can slide on the corresponding target curves,which provides more freedom for the surface registration than the point-based registration methods.Experiments on the real surfaces with point and curve landmarks demonstrate the efficiency,efficacy and robustness of the proposed method.展开更多
文摘In this paper,we discuss a new multilevel method for the vascular surface registration.Such registration is used for hemodynamic calculations.Special care is given to the discretization of the distance function and regularizer,as well as to the surface coarsening.We demonstrate the effectiveness of our method of vascular data used in flow computations.
基金Supported by the National Natural Science Foundation of China(No.51474217,41501562)the Open Fund Program of Henan Engineering Laboratory of Pollution Control and Coal Chemical Resources Comprehensive Utilization(No.502002-B07,502002-A04)
文摘In order to obtain and master the surface thermal deformation of paraboloid antennas,a fast iterative closest point( FICP) algorithm based on design coordinate guidance is proposed,which can satisfy the demands of rapid detection for surface thermal deformation. Firstly,the basic principle of the ICP algorithm for registration of a free surface is given,and the shortcomings of the ICP algorithm in the registration of surface are analysed,such as its complex computation,long calculation time,low efficiency,and relatively strict initial registration position. Then an improved FICP algorithm based on design coordinate guidance is proposed. Finally,the FICP algorithm is applied to the fast registration test for the surface thermal deformation of a paraboloid antenna. Results indicate that the approach offers better performance with regard to fast surface registration and the algorithm is more simple,efficient,and easily realized in practical engineering application.
基金supported in part by the National Natural Science Foundation of China (No.61403357)Anhui Provincial Natural Science Foundation (No.1508085QF122)Fundamental Research Funds for the Central Universities (No.WK0110000044)
文摘Surface registration brings multiple scans into a common coordinate system by aligning their overlapping components. This can be achieved by finding a few pairs of matched points on different scans using local shape descriptors and employing the matches to compute transformations to produce the alignment. By defining a unique local reference frame(LRF) and attaching an LRF to shape descriptors,the transformation can be computed using only one match based on aligning the LRFs. This paper proposes a local voxelizer descriptor,and the key ideas are to define a unique LRF using the support around a basis point,to perform voxelization for the local shape within a cubical volume aligned with the LRF,and to concatenate local features extracted from each voxel to construct the descriptor. An automatic rigid registration approach is given based on the local voxelizer and an expanding strategy that merges descriptor representations of aligned scans. Experiments show that our registration approach allows the acquisition of 3D models of various objects,and that the local voxelizer is robust to mesh noise and varying mesh resolution,in comparison to two state-of-the-art shape descriptors.
基金supported by the China National Natural Science Foundation(61872224,12090021).
文摘This paper proposes a novel method to compute the diffeomorphic registration of 3D surfaces with point and curve feature landmarks.First the surfaces are mapped to the canonical domain by a curve constrained harmonicmap,where the landmark curves are straightened to line segments and their positions and inclining angles are determined intrinsically by the surface geometry and its curve landmarks.Then,the canonical domains are registered by aligning the corresponding point and straight line segments using the dynamic quasiconformal map(DQCM),which introduces the combinatorial diagonal switches to the quasiconformal optimization such that the resultant map is diffeomorphic.The end points of the source curve landmarks are mapped to their corresponding points on the target surface,while the interior points of the source curves can slide on the corresponding target curves,which provides more freedom for the surface registration than the point-based registration methods.Experiments on the real surfaces with point and curve landmarks demonstrate the efficiency,efficacy and robustness of the proposed method.
