B-spline Interpolation Method Research Articles

Subpixel mapping on remote sensing imagery using a prediction model combining wavelet transform and radial basis function neural network

Soft classification methods can be used for mixed-pixel classification on remote sensing imagery by estimating different land cover class fractions of every pixel. However, the spatial distribution and location of these class components within the pixel remain unknown. To map land cover at subpixel scale and increase the spatial resolution of land cover classification maps, in this paper, a prediction model combining wavelet transform and Radial Basis Functions (RBF) neural network, abbreviated as Wavelet-RBFNN, is constructed by predicting high-frequency wavelet coefficients from low-frequency coefficients at the same resolution with RBF network and taking wavelet coefficients at coarser resolution as training samples. According to different land cover class fraction images obtained from mixed-pixel classification, based on the assumption of neighborhood dependence of wavelet coefficients, subpixel mapping on remote sensing imagery can be accomplished through two steps, i.e., prediction of land cover class compositions within subpixels and hard classification. The experimental results obtained with artificial images, QuickBird image and Landsat 7 ETM+ image indicate that the subpixel mapping method proposed in this paper can successfully produce super-resolution land cover classification maps from remote sensing imagery, outperforming cubic B-spline and Kriging interpolation method in visual effect and prediction accuracy. The Wavelet-RBFNN model can also be applied to simulate higher spatial resolution image, and automatically identify and locate land cover targets at the subpixel scales, when the cost and availability of high resolution imagery prohibit its use in many areas of work.

템플릿 정합과 B-Spline 보간에 의한 3차원 광학 영상 처리

본 논문에서는 비젼을 이용한 영상처리 기술을 기반으로 비접촉식 미세 측정 광학기에 의해 측정된 이미지를 템플릿 매칭과 B-Spline 보간법에 의해 보다 빠르고, 정밀한 복원 기법을 제안한다. 이를 위해 먼저 각각의 이미지로부터 매칭 템플릿과 피 매칭 템플릿을 검출한다. 그런 다음 기준면으로부터 두 이미지의 중첩되는 부분의 롤, 피치, 요 오차를 보정하여 정합시킨다. 그리고 B-Spline 보간법에 의해 정합된 부분을 연속화한다. 마지막으로, 제안된 방법은 실험을 통해 그 응용 가능성을 증명한다. The purposes of this paper is to propose new techniques to reconstruct measured optical images by using the template matching and B-Spline interpolation method based on image processing technology. To do this, we detect the matching template and non-matching template from each optical image. And then, we match the overlaped images from base level by correcting roll, pitch, and yaw error of images. At last, the matching image is interpolated by B-Spline interpolation. Finally, we show the effectiveness and feasibility of the proposed method through some experiments.

Trajectory planning of multi-robot coordination platform for locating large subassembly

In the manufacturing engineering field, a multi-robot coordination platform is often used to adjust a large subassembly's location (including position and orientation). This paper introduces an open spherical joint coupling between the subassembly and every robot manipulator and presents a B-spline interpolation trajectory planning method for the manipulators. The location of the subassembly can be described with an element of the group of spatial displacement in Euclidean space. The trajectory of every manipulator can be obtained through finding a smooth motion of the subassembly and then mapping it to the corresponding axes of every manipulator. Unit quaternion is adopted for describing a given set of orientations, and then a cubic B-spline interpolation method is applied to calculate the position and orientation curves, respectively. Finally, the two curves are fused. This paper proves that all the motion points of the subassembly are continuous in the same order as the B-spline function.

Ｂスプライン補間を用いた逐次軌道計画とモデル予測制御を併用した船舶の運動制御

In this paper, we discuss the motion control of underactuated ocean vehicles by using trajectory planning and trajectory tracking control. Important factors which greatly affect the control performance are their model errors, disturbances, obstacles, and actuator constraints. To solve these problems, we attempt to apply the B-spline interpolation method for trajectory planning and model predictive control for trajectory tracking control. We propose a new online control algorithm for the underactuated ocean vehicles and evaluate the performance of the proposed algorithm by numerical case studies.

Inflation of elastomeric circular membranes using network constitutive equations

The present paper deals with the use of network-based hyperelastic constitutive equations in the context of thin membranes inflation. The study focus on the inflation of plane circular membranes and the materials are assumed to obey Gaussian and non-Gaussian statistical chains network models. The governing equations of the inflation of axisymmetric thin rubber-like membranes are briefly recalled. The material models are implemented in a numerical tool that incorporates an efficient B-spline interpolation method and a coupled Newton–Raphson/arc-length solving algorithm. Two numerical examples are studied: the homogeneous inflation of spherical balloons and the inflation of initially plane circular membranes. In the second example, the inflation profiles and the distributions of extension ratios along the membrane are extensively analysed during the inflation process. Both examples highlight the need of an accurate modelling of the strain-hardening phenomenon in elastomers.

Sculptured surface recognition and localization strategy in the CMM process

This paper presents a sculptured surface recognition and localization strategy for the inspection process using the CMM. First, the database is generated from the CAD data based on the Z-Layer concept. Then, the three-dimensional shape of the object on the CMM table is constructed using a vision guided CMM. Two vision cameras are implemented to guide the CMM to the object, and B-spline interpolation method is applied to generate a surface that passes through the obtained data points. As a following step, the Z-layers of the generated surface are created and the geometric properties are calculated to determine the best matching surface in the database. Rough location and orientation of the object are determined by analyzing the image data, and the minimization algorithm is applied as a next step to obtain more accurate localization results. The experimental results show that the proposed method can be applied effectively for sculptured surface recognition and localization in the inspection processes.

The general B-spline interpolation method and its application to the modification of curves and surfaces

Direct manipulation of B-spline control points has been used for modifying B-spline curves and surfaces. But, designers usually wish to modify shapes in more direct ways in practical designing situations, such as moving a point on a curve to some desirable location or modifying a tangent vector at some point on a curve into another direction etc. The author will propose a method that enables arbitrary and direct modification of curves by constructing a displacement function. Moreover, a systematic B-spline interpolation method which has enough generality for practical use will be proposed. The method is also available for surfaces and some interesting applications will be shown.

Response statistics of van der Pol oscillators excited by white noise

The joint probability density function of the state space vector of a white noise exoited van der Pol oscillator satisfics a Fokker-Planck-Kolmogorov (FPK) equation. The paper describes a numerical procedure for solving the transient FPK equation based on the path integral solution (PIS) technique. It is shown that by combining the PIS with a cubic B-spline interpolation method, numerical solution algorithms can be implemented giving solutions of the FPK equation that can be made accurate down to very low probability levels. The method is illustrated by application to two specific examples of a van der Pol oscillator.

Dose distribution study for an experimental gamma-source

Dose distribution studies were carried out using different dosimetric techniques for the purpose of transferring the respective methodologies to a semi-industrial Gamma Irradiation plant (UTR GAMA-Pi). The work was performed using a Cobalt-60 experimental source (Graviner, England - initial activity - 1/3/71 - 3.7X10 14 Bq), and different dosimetric systems (Fricke system, ethanol monochlorobenzene and polymethyl methacrylate). The dose distribution in the irradiation chamber, with a volume of 65X50X20 cm 3, was calculated using a two-dimensional B-Spline interpolation method.