Papers by Keyword: Spline Interpolation

Abstract: The traditional fixed pitch error compensation method exists some defects, such as sampling points are not comprehensive and the necessary compensation points are easy to miss. Faced with these problems, this paper presented a new pitch error compensation method based on the open numerical control system. With this method, the traditional measurement points were serried, and more pitch error data were measured. Then calculated the error data with the cubic spline interpolation computation method, and the compensation location and value were obtained according to the accuracy requirement. The pitch error compensation was completed when the data inputted into the open numerical control system with a defined format.

Abstract: Developing a true 3D experimental stress analysis technique has been the holy grail of solid mechanics researchers since the genesis of the field. Combined the high-resolution x-ray computer tomography (Micro CT) with the 2D speckle photography technique developed by one of us (Chiang), we recently proposed a new 3D strain analysis technique called Digital Volumetric Speckle Photography (DVSP). The elements of DVSP technique are as follows. A reference volumetric image of the specimen is recorded by a Micro-CT scan and stored as a reference. Under load the deformed CT image of the specimen is also recorded. Both volume images are divided into subimages of certain voxel arrays. Each corresponding pair of the subimages are ‘compared’ via a two-step 3D Fourier Transform analysis. The result is a 3D map of displacement vectors representing the collective displacement experienced by all the speckles within the subset of voxels. Strain distribution of the entire specimen can then be calculated using appropriate displacement strain relations. Application of this technique to strain mapping of red sandstone and composite are presented.

Abstract: When low-spline interpolation algorithm is adopted by super-resolution reconstruction for video images, there are some defects, such as saw tooth and blur edge, if the result image is magnified. In this paper, high-order spline interpolation algorithm is introduced and it is optimized. Firstly, the common low-spline interpolation algorithms are analyzed and their shortcomings are pointed out. Then cubic spline interpolation algorithm is discussed. If the image is rotated by cubic spline interpolation algorithm, the magnified image may be not correctly displayed and the image can not be registered in super-resolution reconstruction. Finally, the cubic spline algorithm has been improved. Experimental results show that the improved cubic spline interpolation algorithm can not only eliminate the edge blur and saw tooth, but also do registration in reconstruction when image is rotating.

Abstract: Biped robots research is mainly concentrated on the control system development and doing simulation, cubic spline interpolation method is widely applied to pre-gait planning work. This paper analyzed the robots walking process and calculated the joint trajectory curves of a walk cycle by using spline interpolation and the quintic polynomial fitting means, verifies that the result obtained by quintic polynomial algorithm tends to be more ideal, it is conducive to maintain walking stability and find the optimal joint angles. The paper provides a theoretical basis for optimizing robots trajectory planning.

Abstract: According to the raw multi-source data, all strata should be standardized. With the aid of the cubic spline interpolation function, the virtual drilling could be created. With the help of Deluanay triangulation, every stratum is turned to triangular net, namely initial stratum surface. A top triangle of stratum is connected with a corresponding bottom triangle of stratum in the net. It makes a triangular prism unit. Finally, according to certain rules, numerous triangular prism units are assembled orderly to form a geologic body. The GTP model can realize 3D strata simulation and the purpose of true three-dimensional.

Abstract: There are a lot of developments focused on 3D surface reconstruction based on 2D contours in recent decades, mostly based on closed contours. Due to the limitation of imperfect technology on material classification and edge extraction, it’s difficult to extract closed contours automatically, and this situation limits the application of 3D surface reconstruction based on contour. This paper designs a reconstruction algorithm based on non-closed contour, which not only provides a new viewpoint for research on 3D reconstruction, but also make 3D reconstruction based on contour more applicable.

Abstract: A visualization algorithm was presented for the optimization of geometrical shape matching in the wheel-rail contact system. The algorithm of the subsection cubic spline interpolation was adopted to fit the wheel-rail profiles curves, and curve boundary was got by the finite difference method; furthermore, the wheel-rail contact positions were figured out by computing the roll angles of wheelset iteratively with the dichotomy. Based on MATLAB and Visual C++, the wheel-rail contact geometrical parameters were calculated and visualized, the simulation results show the algorithm has the strong robustness.

Abstract: The damage analysis based on the modal parameters usually need to compare the test data with the computed data by theoretical analysis. In bridge structure damage analysis, it is impossible that the sensors are set at every node. So the test data need to be extended to every node by using interpolation technology. In the paper, three interpolation methods, cubic interpolation method, cubic spline interpolation method and sinc interpolation method, are introduced. Their applications in bridge structure damage analysis are discussed. The experiment results show that the best interpolation method is cubic spline interpolation method. Using the data processed by interpolation technology can well obtain the damage location of bridge.

Abstract: For the purpose of measuring the micro changes of morphological parameters of melon organ, this paper put forth a new algorithm based on mathematical morphology and spline interpolation to obtain the phenotype information of melon such as area and horizontal and vertical diameter and developed a high-resolution non-destructive and contactless measuring system based on vision processing to get the projection area of melon and its diameter. The algorithm is easy to carry out, and can get more ideal edge information than some traditional algorithms. It supplies theoretical basis for revealing the combined response relationship and temporal and spatial variation character between melon morphologies and key environmental factors.

Abstract: In this paper, based on the output feedback decoupling, curve fitting and spline interpolation method, a mathematical model is presented for nonlinear dynamical system wherein only system inputs and outputs are known.