Updated on 2022/05/22

写真a

 
MAEKAWA, Takashi
 
Affiliation
Faculty of Science and Engineering, Waseda Research Institute for Science and Engineering
Job title
Senior Researcher(Professor)

Education

  •  
    -
    1993

    Massachusetts Institute of Technology   School of Engineering,Department of Ocean Engineering   Department of Ocean Engineering  

  •  
    -
    1976

    Waseda University   School of Science and Engineering   Department of Mechanical Engineering  

Degree

  • Massachusetts Institute of Technology (USA)   PH.D.

Research Experience

  • 2019.04
    -
    Now

    Waseda University

  • 2019.04
    -
    Now

    Yokohama National University   Professor Emeritus

  • 2003.04
    -
    2019.03

    Yokohama National University Faculty of Engineering Division of Systems Research

  • 1999.07
    -
    2003.03

    M.I.T. , School of Engineering, Dept. of Ocean Enginnering, Principal Research Scientist

  • 1994.09
    -
    1999.06

    M.I.T. , School of Engineering, Dept. of Ocean Enginnering, Research Scientist/Lecturer

  • 1993.07
    -
    1994.08

    M.I.T. , School of Engineering, Dept. of Ocean Enginnering, Postdoctoral Associate

  • 1989.08
    -
    1993.06

    M.I.T. , School of Engineering, Dept. of Ocean Enginnering, Research Assistant

  • 1978.04
    -
    1989.07

    Bridgestone Corporation Engineer

▼display all

Professional Memberships

  • 2020.08
    -
    Now

    Japan Society for Industrial and Applied Mathematics

  •  
     
     

    The Japan Society of Mechanical Engineers

 

Research Areas

  • Design engineering

Papers

  • Accurate High-Order Derivatives of Geodesic Paths on Smooth Surfaces

    Felix Scholz, Takashi Maekawa

    Computer-Aided Design   140   103082 - 103082  2021.11  [Refereed]

    Authorship:Last author

    DOI

  • Fabrication of doubly-curved CFRP shell structures with control over fiber directions

    Masahito Takezawa, Yuto Otoguro, Kohei Matsuo, Tadahiro Shibutani, Akio Sakurai, Takashi Maekawa

    Computer-Aided Design   136   103028 - 103028  2021.07  [Refereed]

    DOI

  • Two-Lane Path Planning of Autonomous Vehicles in 2.5D Environments

    Riku Usami, Yuji Kobashi, Taiki Onuma, Takashi Maekawa

    IEEE Transactions on Intelligent Vehicles   5 ( 2 ) 281 - 293  2020.06  [Refereed]

    DOI

  • Control of lines of curvature for plate forming in shipbuilding

    M. Takezawa, K. Matsuo, T. Maekawa

    Computer Aided Geometric Design   75  2019.11  [Refereed]

  • Automatic Two-Lane Path Generation for Autonomous Vehicles Using Quartic B-Spline Curves

    Taketoshi Suzuki, Riku Usami, Takashi Maekawa

    IEEE Transactions on Intelligent Vehicles   3 ( 4 ) 547 - 558  2018.12  [Refereed]

    DOI

  • Embedding QR codes onto B-spline surfaces for 3D printing

    Ryosuke Kikuchi, Sora Yoshikawa, Pradeep Kumar Jayaraman, Jianmin Zheng, Takashi Maekawa

    CAD Computer Aided Design   102   215 - 223  2018.09  [Refereed]

     View Summary

    Recent advance of Additive Manufacturing technologies allows us to manufacture various parts used in real-world products. Consequently, product tracking of such 3D printed parts is an important issue. Quick Response (QR) code which is a two-dimensional matrix barcode invented by Denso, a Japanese automotive industry, in 1994, can be used for this purpose. It can store more data than the 1D barcode in a smaller space, and using a smartphone as a scanner, one can directly visit a website where all the information of the parts is stored. However, QR codes require secondary procedures to add them to products and are also vulnerable to wear and tear. Moreover, QR codes cannot be added to freeform surfaces, but only to developable surfaces. In this paper we propose a novel technique to embed QR codes onto CAD models consisting of freeform surfaces represented by B-spline surfaces, which produces 3D QR codes. 3D QR codes work similar to 2D QR codes and can be read by existing QR scanners, but are designed by grooving the surface to obtain light and dark regions caused by ambient occlusion. Unlike conventional QR codes, 3D QR codes do not fall off from the part and can even be painted if necessary. Furthermore, we do not need to prepare dark-colored and light-colored materials for 3D printing as the dark color is provided by the grooving. We demonstrate the effectiveness of our technique with various examples.

    DOI

  • An image processing approach to feature-preserving B-spline surface fairing

    Taro Kawasaki, Pradeep Kumar Jayaraman, Kentaro Shida, Jianmin Zheng, Takashi Maekawa

    CAD Computer Aided Design   99   1 - 10  2018.06  [Refereed]

     View Summary

    Reverse engineering of 3D industrial objects such as automobiles and electric appliances is typically performed by fitting B-spline surfaces to scanned point cloud data with a fairing term to ensure smoothness, which often smooths out sharp features. This paper proposes a radically different approach to constructing fair B-spline surfaces, which consists of fitting a surface without a fairing term to capture sharp edges, smoothing the normal field of the constructed surface with feature preservation, and reconstructing the B-spline surface from the smoothed normal field. The core of our method is an image processing based feature-preserving normal field fairing technique. This is inspired by the success of many recent research works on the use of normal field for reconstructing mesh models, and makes use of the impressive simplicity and effectiveness of bilateral-like filtering for image denoising. In particular, our approach adaptively partitions the B-spline surface into a set of segments such that each segment has approximately uniform parameterization, generates an image from each segment in the parameter space whose pixel values are the normal vectors of the surface, and then applies a bilateral filter in the parameter domain to fair the normal field. As a result, our approach inherits the advantages of image bilateral filtering techniques and is able to effectively smooth B-spline surfaces with feature preservation as demonstrated by various examples.

    DOI

  • Survey on geometric iterative methods and their applications

    Hongwei Lin, Takashi Maekawa, Chongyang Deng

    CAD Computer Aided Design   95   40 - 51  2018.02  [Refereed]

     View Summary

    Geometric iterative methods (GIM), including the progressive–iterative approximation (PIA) and the geometric interpolation/approximation method, are a class of iterative methods for fitting curves and surfaces with clear geometric meanings. In this paper, we provide an overview of the interpolatory and approximate geometric iteration methods, present the local properties and accelerating techniques, and show their convergence. Moreover, because it is easy to integrate geometric constraints in the iterative procedure, GIM has been widely applied in geometric design and related areas. We survey the successful applications of geometric iterative methods, including applications in geometric design, data fitting, reverse engineering, mesh and NURBS solid generation.

    DOI J-GLOBAL

  • Ship hull form modeling by geometric iterative method

    Takezawa Masahito, Matsuo Kohei, Maekawa Takashi

    Journal of the Japan Society of Naval Architects and Ocean Engineers   27   149-160  2018  [Refereed]

    DOI CiNii

  • Adaptive direct slicing of volumetric attribute data represented by trivariate B-spline functions

    Yuhi Sasaki, Masahito Takezawa, Seungki Kim, Hiroshi Kawaharada, Takashi Maekawa

    International Journal of Advanced Manufacturing Technology   91 ( 5-8 ) 1791 - 1807  2017.07  [Refereed]

     View Summary

    We introduce a framework for modeling of heterogeneous objects in terms of trivariate B-spline functions and a method for slicing them directly for additive manufacturing. We first fit volumetric attribute data associated with the geometry in terms of trivariate B-spline functions under the assumption that the geometric volume is already defined by the trivariate B-spline functions. Then, the B-spline volume and the associated attribute data are directly sliced without converting them to stereo-lithography format, resulting in a tool path with fewer errors. Furthermore, adaptive ray shooting is introduced in the slicing plane so that the zigzag tool path passes through all the tangential intersection points of the heterogeneous objects to represent all the feature points in the fabricated model. Complex examples illustrate the effectiveness of our method.

    DOI

  • Curvature sensitive analysis of axially compressed cylindrical tubes with corrugated surface using isogeometric analysis and experiment

    Takuma Imai, Tadahiro Shibutani, Kazumi Matsui, Seitoku Kumagai, Dang Tien Tran, Kaiyuan Mu, Takashi Maekawa

    COMPUTER AIDED GEOMETRIC DESIGN   49   17 - 30  2016.12  [Refereed]

     View Summary

    We study the effects of curvature on the energy absorption characteristics of cylindrical corrugated tubes under compression by isogeometric analysis and experiments. The corrugated volume is constructed by revolving a wavelike B-spline profile surface about the vertical axis. The curvature at peaks of the profile curve is gradually increased from a smaller value to a larger value while the wavelength and amplitude are kept unchanged. This leads to three curvature distribution patterns, which are found to significantly affect the energy absorption characteristics of the corrugated tube. Examples show that the tube with the largest curvature pattern absorbs around 21% more energy than that with the smallest curvature pattern. (C) 2016 Elsevier B.V. All rights reserved.

    DOI

  • Fabrication of freeform objects by principal strips

    Masahito Takezawa, Takuma Imai, Kentaro Shida, Takashi Maekawa

    ACM Transactions on Graphics   35 ( 6 ) 1 - 12  2016.11  [Refereed]

    DOI

  • Tool path generation for chamfering drill holes of a pipe with constant width

    Takato Sato, Youichi Sato, Takashi Maekawa

    COMPUTER-AIDED DESIGN   78 ( SI ) 26 - 35  2016.09  [Refereed]

     View Summary

    When drilling circular holes into metal circular pipes, burr is generated at the hole entrance as well as at the hole exit. The burrs generated at the edge curves associated with the outer and inner pipe surfaces must be removed by constant chamfering. Geometrically, the two edge curves can be defined as cylinder to-pipe intersection curves. In this paper, we employ differential geometric properties of the surface-to-surface intersection curves in order to generate an interference-free tool path with constant chamfering for a ball-end cutter. We demonstrate the effectiveness of our method by conducting experiments with physical pipe models. (C) 2016 Elsevier Ltd. All rights reserved.

    DOI

  • Development of microscopic shape measuring system using iterative photometric stereo techniques

    IMOTO Harutaka, MACHIDA Kenitiro, YAMAURA Yusuke, TADENUMA Hiroshi, MAEKAWA Takashi

      82 ( 835 ) 15-00512  2016.02  [Refereed]

    DOI CiNii J-GLOBAL

  • Automatic generation of LEGO building instructions from multiple photographic images of real objects

    Takuya Kozaki, Hiroshi Tedenuma, Takashi Maekawa

    COMPUTER-AIDED DESIGN   70   13 - 22  2016.01  [Refereed]

     View Summary

    We introduce a system to reconstruct large scale LEGO models from multiple two dimensional images of objects taken from different views. We employ a unit voxel with an edge length ratio of 5:5:6 for the shape from silhouette method that reconstructs an octree voxel-based three dimensional model with color information from images. We then convert the resulting voxel model with color information into a LEGO sculpture. In order to minimize the number of LEGO bricks, we use a stochastic global optimization method, simulated annealing, to hollow the model as much as possible but keep its strength for portability. Several real complex LEGO models are provided to demonstrate the effectiveness of the proposed method. (C) 2015 Elsevier Ltd. All rights reserved.

    DOI

  • Shape reconstruction from a normal map in terms of uniform bi-quadratic B-spline surfaces

    Yusuke Yamaura, Takaki Nanya, Harutaka Imoto, Takashi Maekawa

    COMPUTER-AIDED DESIGN   63   129 - 140  2015.06  [Refereed]

     View Summary

    This paper studies the recovery of the height field function of an object from its surface normal vectors in terms of uniform bi-quadratic B-spline surfaces. The study is motivated by two modern technological needs namely, the recovery of the height field function of an object from its surface normal vectors obtained by photometric stereo techniques, and the introduction of new design methodology of streamlined aesthetic surfaces through the direct editing of normal vectors. Our mathematical formulation for explicit surface reconstruction is based on differential geometry and geometric modeling techniques. Complex examples are provided to demonstrate the effectiveness of the proposed method. (c) 2015 Elsevier Ltd. All rights reserved.

    DOI

  • Surface design based on direct curvature editing

    Yuki Kineri, Shuhei Endo, Takashi Maekawa

    COMPUTER-AIDED DESIGN   55 ( 10 ) 1 - 12  2014.10  [Refereed]

     View Summary

    This paper presents a novel method for modifying the shapes of existing uniform bi-cubic B-spline surfaces by interactively editing the curvatures along isoparametric curves. The method allows us to edit the curvatures of the two intersecting isoparametric curves at each knot with specified positions, unit tangents, and unit normals. The user adjusts the radii of circles, representing the radii of curvature in the u and v isoparametric directions directly via a GUI without having to work with control points and knots. Such shape specifications are converted into iterative repositionings of the control points on the basis of geometrical rules. Using these point-based curvature-editing techniques, we successfully embedded log-aesthetic curves into existing surfaces along their isoparametric curves. Moreover, we were able to distribute the cross curvature with log-aesthetic variation along the isoparametric curves. We applied our technique to the design of automobile hood surfaces to demonstrate the effectiveness of our algorithms. (C) 2014 Elsevier Ltd. All rights reserved.

    DOI J-GLOBAL

  • Differential geometry properties of lines of curvature of parametric surfaces and their visualization

    Han Kyul Joo, Tatsuya Yazaki, Masahito Takezawa, Takashi Maekawa

    GRAPHICAL MODELS   76 ( 4 ) 224 - 238  2014

     View Summary

    We present algorithms for computing the differential geometry properties of lines of curvature of parametric surfaces. We derive a unit tangent vector, curvature vector, binormal vector, torsion, and algorithms to evaluate their higher-order derivatives of lines of curvature of parametric surfaces. Among these quantities, it is shown that the curvature and its first derivative of the lines of curvature lend a hand for the formation of curved plates in shipbuilding. We also visualize the twist of lines of curvature, which enables us to observe how much the osculating plane of the line of curvature turns about the tangent vector. (C) 2014 Elsevier Inc. All rights reserved.

    DOI

  • B-spline surface fitting by iterative geometric interpolation/approximation algorithms

    Yuki Kineri, Mingsi Wang, Hongwei Lin, Takashi Maekawa

    COMPUTER-AIDED DESIGN   44 ( 7 ) 697 - 708  2012.07  [Refereed]

     View Summary

    Recently, the use of B-spline curves/surfaces to fit point clouds by iteratively repositioning the B-spline's control points on the basis of geometrical rules has gained in popularity because of its simplicity, scalability, and generality. We distinguish between two types of fitting, interpolation and approximation. Interpolation generates a B-spline surface that passes through the data points, whereas approximation generates a B-spline surface that passes near the data points, minimizing the deviation of the surface from the data points. For surface interpolation, the data points are assumed to be in grids, whereas for surface approximation the data points are assumed to be randomly distributed. In this paper, an iterative geometric interpolation method, as well as an approximation method, which is based on the framework of the iterative geometric interpolation algorithm, is discussed. These two iterative methods are compared with standard fitting methods using some complex examples, and the advantages and shortcomings of our algorithms are discussed. Furthermore, we introduce two methods to accelerate the iterative geometric interpolation algorithm, as well as a method to impose geometric constraints, such as reflectional symmetry, on the iterative geometric interpolation process, and a novel fairing method for non-uniform complex data points. Complex examples are provided to demonstrate the effectiveness of the proposed algorithms. (C) 2012 Elsevier Ltd. All rights reserved.

    DOI

  • Point-tangent/point-normal B-spline curve interpolation by geometric algorithms

    Shu-ichi Gofuku, Shigefumi Tamura, Takashi Maekawa

    COMPUTER-AIDED DESIGN   41 ( 6 ) 412 - 422  2009.06

     View Summary

    We introduce a novel method to interpolate a set of data points as well as unit tangent vectors or unit normal vectors at the data points by means of a B-spline curve interpolation technique using geometric algorithms. The advantages of our algorithm are that it has a compact representation, it does not require the magnitudes of the tangent vectors or normal vectors, and it has C-2 continuity. We compare our method with the conventional curve interpolation methods, namely, the standard point interpolation method, the method introduced by Piegl and Tiller, which interpolates points as well as the first derivatives at every point, and the piecewise cubic Hermite interpolation method. Examples are provided to demonstrate the effectiveness of the proposed algorithms. (C) 2009 Elsevier Ltd. All rights reserved.

    DOI J-GLOBAL

  • 3D shape reconstruction from 2D images

    Daisuke Hirano, Yusuke Funayama, Takashi Maekawa

    Computer-Aided Design and Applications   6 ( 5 ) 701 - 710  2009

     View Summary

    We present a method of reconstructing a 3D model from several 2D images of an object taken from different views. The data acquisition system consists of a camera on a tripod, and a computer-controlled turntable. We employ the Shape-From-Silhouette (SFS) method, which constructs a voxel-based 3D model from silhouette images. The concave shapes are further carved by using the space carving technique. In order to make the resulting model compatible with the CAD/CAM system, the voxel model is converted into a triangular mesh using the Marching Cubes algorithm. Since the mesh generated from the voxel model by using the Marching Cubes algorithm inherits the staircase effect, the mesh is adjusted to recover the object precisely by using silhouette images. Finally, we evaluate the accuracy of the proposed method. The reconstructed models of complex objects show the effectiveness of the proposed inexpensive 3D shape reconstruction system.© 2009 CAD Solutions, LLC.

    DOI

  • Computation of the Solutions of Nonlinear Polynomial Systems in the Barycentric Bernstein Basis

    M. Reuter, T. Mikkelsen, E. Sherbrooke, T. Maekawa, N. M. Patrikalakis

    The Visual Computer   24 ( 3 ) 187-200  2008  [Refereed]

  • Approximation of involute curves for CAD-system processing

    Fumitaka Higuchi, Shuuichi Gofuku, Takashi Maekawa, Harish Mukundan, Nicholas M. Patrikalakis

    ENGINEERING WITH COMPUTERS   23 ( 3 ) 207 - 214  2007.09  [Refereed]

     View Summary

    In numerous instances, accurate algorithms for approximating the original geometry is required. One typical example is a circle involute curve which represents the underlying geometry behind a gear tooth. The circle involute curves are by definition transcendental and cannot be expressed by algebraic equations, and hence it cannot be directly incorporated into commercial CAD systems. In this paper, an approximation algorithm for circle involute curves in terms of polynomial functions is developed. The circle involute curve is approximated using a Chebyshev approximation formula (Press et al. in Numerical recipes, Cambridge University Press, Cambridge, 1988), which enables us to represent the involute in terms of polynomials, and hence as a Bezier curve. In comparison with the current B-spline approximation algorithms for circle involute curves, the proposed method is found to be more accurate and compact, and induces fewer oscillations.

    DOI J-GLOBAL

  • Interpolation by Geometric Algorithm

    Takashi Maekawa, Yasunori Matsumoto, Ken Namiki

    Computer Aided Design   39 ( 4 ) 313-323  2007.04  [Refereed]

    DOI J-GLOBAL

  • Surface Faring Using Circular Highlight Lines

    Yu Nishiyama, Yoh Nishimura, Takayuki Sasaki, Takashi Maekawa

    Computer-Aided Design and Applications   4 ( 1-4 ) 405 - 414  2007  [Refereed]

     View Summary

    We herein propose a novel method for removing irregularities of B-spline surfaces via smoothing circular highlight lines. A circular highlight line is defined as a set of points on a surface such that the distance between a circular light source and an extended surface normal to be zero. Circular highlight lines allow us to capture the surface fairness in all directions, whereas conventional method, which uses a family of parallel straight lines for light sources, can capture the surface irregularity only in one direction. This method of correcting surface irregularities through circular highlight lines is intuitive and allows non-skilled persons to generate surfaces that can satisfy requirements imposed by downstream applications. Nonlinear equations that relate the difference between the circular highlight lines of the current surface and the target curves in the parameter space are formulated in terms of control points of the surface to be modified. The nonlinear governing equations are solved by Newton’s method. The effectiveness of these algorithms is demonstrated through examples. © 2007 by CAD Solutions.

    DOI

  • Algorithms for optimal partial matching of free-form objects with scaling effects

    KH Ko, T Maekawa, NM Patrikalakis

    GRAPHICAL MODELS   67 ( 2 ) 120 - 148  2005.03  [Refereed]

     View Summary

    A free-form object matching problem is addressed in this paper. Two methods are proposed to solve a partial matching problem with scaling effects and no prior information on correspondence or the rigid body transformation involved. The first method uses umbilical points, which behave as fingerprints of a surface and their qualitative properties can be used for matching purposes. The second method uses an optimization scheme based on the extension of the KH curvature matching method [Comput. Aided Design 35 (2003) 913], first introduced in the context of a matching problem without scaling effects. Two types of curvatures, the Gaussian and the mean curvatures, are used to establish correspondences between two objects. The curvature matching method is formulated in terms of minimization of an objective function depending on the unknown scaling factor, and the rigid body transformation parameters. The accuracy and complexity of the proposed methods as well as the convergence for the optimization approach are analyzed. Examples illustrate the two methods. (C) 2004 Elsevier Inc. All rights reserved.

    DOI J-GLOBAL

  • Circular Highlight/Relfection Lines

    T. Maekawa, Y. Nishimura, T. Sasaki

    Computer-Aided Design and Applications   2 ( 1-4 ) 291-300  2005  [Refereed]

  • Methods for feature-based design of heterogeneous solids

    H Liu, T Maekawa, NM Patrikalakis, EM Sachs, W Cho

    COMPUTER-AIDED DESIGN   36 ( 12 ) 1141 - 1159  2004.10  [Refereed]

     View Summary

    This paper presents a parametric and feature-based methodology for the design of solids with local composition control (LCC). A suite of composition design features are conceptualized and implemented. The designer can use them singly or in combination, to specify the composition of complex components. Each material composition design feature relates directly to the geometry of the design, often relying on user interaction to specify critical aspects of the geometry. This approach allows the designer to simultaneously edit geometry and composition by varying parameters until a satisfactory result is attained. The identified LCC features are those based on volume, transition, pattern, and (user-defined) surface features. The material composition functions include functions parametrized with respect to distance or distances to user-defined geometric features; and functions that use Laplace's equation to blend smoothly various boundary conditions including values and gradients of the material composition on the boundaries. The Euclidean digital distance transform and the Boundary Element Method are adapted to the efficient computation of composition functions. Theoretical and experimental complexity, accuracy and convergence analyses are presented. The representations underlying the composition design features are analytic in nature and therefore concise. Evaluation for visualization and fabrication is performed only at the resolutions required for these purposes, thereby reducing the computational burden. (C) 2003 Elsevier Ltd. All rights reserved.

    DOI J-GLOBAL

  • Surface to Surface Intersections

    N. M. Patrikalakis, T. Maekawa, K. H. Ko, H. Mukundan

    Computer-Aided Design and Applications   1 ( 1-4 ) 449 - 457  2004

     View Summary

    This paper presents an overview of surface intersection problems and focuses on the rational polynomial parametric/rational polynomial parametric surface intersection case including transversal and tangential intersections. Emphasis is placed on marching methods with a discussion of the problems with conventional tracing algorithms. An approach using a validated interval ordinary differential equation system solver is outlined and illustrated with examples, which offers significant advantages in robustness over conventional marching schemes. © 2004 by CAD Solutions Company Limited.

    DOI

  • Shape Intrinsic Properties for Free-Form Object Matching

    K. H. Ko, T. Maekawa, N. M. Patrikalakis, H. Masuda, F. E. Wolter

    Journal of Computing and Information Science in Engineering   3 ( 4 ) 325 - 333  2003.12  [Refereed]

     View Summary

    Despite extensive research and rapid increase of computing power, free-form object matching still remains a challenging problem in CAD/CAM areas. In this paper, various object features are discussed, and matching methods which use these features are introduced along with robust computational algorithms for umbilical points and intrinsic wireframes. The similarity of matched objects is assessed with three proposed tests. Each algorithm is demonstrated with examples.

    DOI

  • An algorithm for optimal free-form object matching

    KH Ko, T Maekawa, NM Patrikalakis

    COMPUTER-AIDED DESIGN   35 ( 10 ) 913 - 923  2003.09  [Refereed]

     View Summary

    A novel method of matching for 3-D-free-form objects (points vs. surface and surface vs. surface) is proposed. The method formulates the problem in terms of solution of a non-linear polynomial equation system, which can be solved robustly by the Interval Projected Polyhedron (IPP) algorithm. Two intrinsic surface properties, the Gaussian and the mean curvatures, are used as object features for matching. The related iso-curvature lines are used to establish the correspondence between two objects. The intersection points of these iso-curvature lines are calculated and sorted out to satisfy the Euclidean constraints from which the translation and rotation transformations are estimated. The performance of the proposed algorithm is also analyzed. This approach can cover global and partial matching, and be applied to automated inspection, copyright protection of NURBS models, and object recognition. Examples illustrate our technique. (C) 2003 Elsevier Science Ltd. All rights reserved.

    DOI J-GLOBAL

  • Surface Construction by Fitting Unorganized Cureves (Jointly worked)

    K. H. Ko, T.Maekawa

    Graphical Models   64 ( 5 ) 316-332  2002  [Refereed]

  • Shape Interrogation for Computer Aided Design and Manufacturing

    N. M, Patrikalakis, T.Maekawa

    Springer-Verlag    2002

  • Efficient simulation of shell forming by line heating

    G Yu, RJ Anderson, T Maekawa, NM Patrikalakis

    INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES   43 ( 10 ) 2349 - 2370  2001.10  [Refereed]

     View Summary

    A simplified thermo-mechanical model for the prediction of angular deformations of metal plates due to line heating is presented. The model utilizes a semi-analytically determined temperature distribution, which incorporates the effects of heat loss and a distributed moving heat source, to find the dimensions of a critical heat-affected region. The dimensions of this region are used to find the angular deformation by an analytic solution method. Predicted values of angular deformation compare well with corresponding values from experimental results. This model is also compared with thermo-mechanical analysis based on the three-dimensional finite element method. The comparisons indicate that the simplified model is fairly accurate and much more efficient in comparison to the finite element solution. (C) 2001 Elsevier Science Ltd. All rights reserved.

    DOI

  • FEM simulation of laser forming of metal plates

    G Yu, K Masubuchi, T Maekawa, NM Patrikalakis

    JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME   123 ( 3 ) 405 - 410  2001.08  [Refereed]

     View Summary

    A finite element model is developed for thermo-mechanical analysis of the process of metal plate forming by laser line heating. A rezoning technique is adopted to greatly reduce the simulation time. The effects of the refinement of mesh size on temperature distribution and final distortion are studied. Comparison between numerical and experimental results shows a good agreement in final distortion of the formed plate. Finally, edge effects in the laser forming process are studied.

    DOI

  • Self-Intersections of Offset Curevs and Surfaces

    J. Wallner, T. Sakkalis, T. Maekawa, H. Pottmann, G. Yu

    International Journal of Shape Modelling   7 ( 1 ) 1-21  2001.06  [Refereed]

  • CNC tool path in terms of B-spline curves

    C Lartigue, F Thiebaut, T Maekawa

    COMPUTER-AIDED DESIGN   33 ( 4 ) 307 - 319  2001.04  [Refereed]

     View Summary

    We present an accurate and efficient method to generate a CNC toot path for a smooth free-form surface in terms of planar cubic B-spline curves which will be fed into a free-form curve interpolator. We assume the use of a three-axis CNC machine tool with a ball end-mill cutter. We first interpolate break points, which art: generated by computing the offset surface-driving plane intersection curve reflecting the curvature, by a planar cubic B-spline curve. We then evaluate the maximum scallop height along a scallop curve by computing the stationary points of the distance function between the scallop curve and the design surface. Furthermore, we compute the maximum pick feed such that the maximum scallop height along a scallop curve coincides with the prescribed tolerance. illustrative examples show the substantial improvements this method achieves over conventional methods where the tool path consists of linear or circular paths. (C) 2001 Elsevier Science Ltd. All rights reserved.

    DOI

  • Optimal development of doubly curved surfaces

    GX Yu, NM Patrikalakis, T Maekawa

    COMPUTER AIDED GEOMETRIC DESIGN   17 ( 6 ) 545 - 577  2000.07  [Refereed]

     View Summary

    This paper presents algorithms for optimal development (flattening) of a smooth continuous curved surface embedded in three-dimensional space into a planar shape. The development process is modeled by in-plane strain (stretching) from the curved surface to its planar development. The distribution of the appropriate minimum strain field is obtained by solving a constrained nonlinear programming problem. Based on the strain distribution and the coefficients of the first fundamental form of the curved surface, another unconstrained nonlinear programming problem is solved to obtain the optimal developed planar shape. The convergence and complexity properties of our algorithms are analyzed theoretically and numerically. Examples show the effectiveness of the algorithms. (C) 2000 Elsevier Science B.V. All rights reserved.

    DOI

  • Differential geometry of intersection curves of two surfaces

    XZ Ye, T Maekawa

    COMPUTER AIDED GEOMETRIC DESIGN   16 ( 8 ) 767 - 788  1999.09  [Refereed]

     View Summary

    We present algorithms for computing the differential geometry properties of intersection curves of two surfaces where the combination of two surfaces can be parametric-parametric, implicit-implicit and parametric-implicit. We derive unit tangent vector, curvature vector, binormal vector, curvature, torsion, and algorithms to evaluate the higher-order derivatives for transversal as well as tangential intersections for all three types of intersection problems. (C) 1999 Elsevier Science B.V. All rights reserved.

    DOI J-GLOBAL

  • An overview of offset curves and surfaces

    T Maekawa

    COMPUTER-AIDED DESIGN   31 ( 3 ) 165 - 173  1999.03  [Refereed]

     View Summary

    A literature survey on offset curves and surfaces up to 1992 was carried out by Pham (Pham B, Offset curves and surfaces: a brief survey. Computer Aided Design 1992; 24(4): 223-229). The objective of this article is to overview the literature after 1992 and those which were not cited in aforementioned paper. The article focuses on five active areas of research on offsets: (1) representing exact offsets in Bezier/B-spline format, (2) approximations, (3) self-intersections, (4) geodesic offsets and (5) general offsets. (C) 1999 Elsevier Science Ltd. All rights reserved.

    DOI J-GLOBAL

  • Computation of inflection lines and geodesics on developable surfaces

    T Maekawa, JS Chalfant

    MATHEMATICAL ENGINEERING IN INDUSTRY   7 ( 2 ) 251 - 267  1999

     View Summary

    A developable surface can be formed by bending or rolling a planar surface without stretching or tearing; in other words, it can be developed or unrolled isometrically onto a plane. This paper describes two main differential geometry properties of developable surfaces that have industrial applications. First, a method for identifying the inflection line of a developable surface is described. Second, geodesic lines between two points on a developable surface are found as an initial value problem, which is easier to solve than the boundary value problem that is normally required.

  • Design for manufacturing using B-spline developable surfaces

    JS Chalfant, T Maekawa

    JOURNAL OF SHIP RESEARCH   42 ( 3 ) 207 - 215  1998.09  [Refereed]

     View Summary

    A developable surface can be formed by bending or rolling a planar surface without stretching or tearing; in other words. it can be developed or unrolled isometrically onto a plane. Developable surfaces are widely used in the manufacture of items that use materials that are not amenable to stretching such as the formation of ducts, shoes, clothing and automobile parts including upholstery and body panels (Frey & Bindschadler 1993). Designing a ship hull entirely of developable surfaces would allow production of the hull using only rolling or bending. Heat treatment would only be required for removal of distortion, thus greatly reducing the labor required to form the hull. Although developable surfaces play an important role in various manufacturing applications, little attention has been paid to implementing developable surfaces from the onset of a design. This paper investigates novel. user friendly methods to design complex objects using B-spline developable surfaces based on optimization techniques. Illustrative examples show the substantial improvements this method achieves over previously developed methods.

  • Design and tessellation of B-Spline developable surfaces

    T Maekawa, J Chalfant

    JOURNAL OF MECHANICAL DESIGN   120 ( 3 ) 453 - 461  1998.09  [Refereed]

     View Summary

    Developable surfaces are widely used in various engineering applications. However, little attention has been paid to implementing developable surfaces from the onset of a design. The first half of the paper describes a user friendly method of designing developable surfaces in terms of a B-Spline representation whose two directrices lie on parallel planes. The second half of the paper investigates a new method for development and tessellation of such B-Spline developable surfaces which is necessary for plate cutting and finite element analysis.

    DOI

  • Efficient and reliable methods for rounded-interval arithmetic

    SL Abrams, W Cho, CY Hu, T Maekawa, NM Patrikalakis, EC Sherbrooke, Ye, X

    COMPUTER-AIDED DESIGN   30 ( 8 ) 657 - 665  1998.07  [Refereed]

     View Summary

    We present an efficient and reliable method for computing the unit-in-the-last-place (ulp) of a double-precision floating-point number, taking advantage of the standard binary representation for floating-point numbers defined by IEEE Std 754-1985. The ulp is necessary to perform software rounding for robust rounded-interval arithmetic (RIA) operations. Hardware rounding, using two of the standard rounding modes defined by IEEE-754, may be more efficient. RIA has been used to produce robust software systems for the solution of systems of nonlinear equations, interrogation of geometric and differential properties of curves and surfaces, curve and surface intersections, and solid modeling. (C) 1998 Elsevier Science Ltd. All rights reserved.

    DOI

  • Analysis and applications of pipe surfaces

    T Maekawa, NM Patrikalakis, T Sakkalis, GX Yu

    COMPUTER AIDED GEOMETRIC DESIGN   15 ( 5 ) 437 - 458  1998.05  [Refereed]

     View Summary

    A pipe (or tubular) surface is the envelope of a one-parameter family of spheres with constant radii r and centers C(t). In this paper we investigate necessary and sufficient conditions for the nonsingularity of pipe surfaces. In addition, when C(t) is a rational function, we develop an algorithmic method for the rational parametrization of such a surface. The latter is based on finding two rational functions alpha(t) and beta(t) such that /C'(t)/(2) = alpha(2)(t) + beta(2)(t) (Lu and Portmann, 1996). (C) 1998 Elsevier Science B.V.

    DOI

  • Self-intersections of offsets of quadratic surfaces: Part II, implicit surfaces

    T Maekawa

    ENGINEERING WITH COMPUTERS   14 ( 1 ) 14 - 22  1998

     View Summary

    The paper investigates self-intersections of offsets of implicit quadratic surfaces, The quadratic surfaces are the simplest curved objects, referred to as quadrics, and are widely used in mechanical design. In an earlier paper, we have investigated the self-intersections of offsets of explicit quadratic surfaces, such as elliptic paraboloid, hyperbolic paraboloid and parabolic cylinder, since not only are they used in mechanical design, but also any regular surface can de locally approximated by such explicit quadratic surfaces. In this paper, we investigate the rest of the quadrics whose offsets may degenerate, i.e, the implicit quadratic-surfaces (ellipsoid, hyperboloid, elliptic cone, elliptic cylinder and hyperbolic cylinder). We found that self-intersection curves of offsets of all the implicit quadratic surfaces are planar implicit conics and their corresponding curve on the progenitor surface can be expressed as the intersection curve between an ellipsoid, whose semi-axes are proportional to the offset distance, and the implicit quadratic surfaces themselves.

    DOI

  • Self-intersections of offsets of quadratic surfaces: Part I, explicit surfaces

    T Maekawa

    ENGINEERING WITH COMPUTERS   14 ( 1 ) 1 - 13  1998

     View Summary

    Although offset surfaces ape widely used in various engineering applications, their degenerating mechanism is not well known in a quantitative manner. Offset surfaces are functionally mole complex than their progenitor surfaces and may degenerate even if the progenitor surfaces are regular. Self-intersections of the offsets of regular surfaces may be induced by concave regions of surface where the positive offset distance exceeds the maximum absolute value of the negative minimum principal curvature or the absolute value of the negative offset distance exceeds the maximum value of the positive maximum principal curvature.
    It is well known that any regular surface can be locally approximated in the neighborhood of a point p by the explicit quadratic surface of the form r(x, y) = [x, y, 1/2 (alpha x(2) + beta y(2))](T) to the second order where -alpha and -beta are the principal curvatures at point p. Therefore investigations of the self-intersecting mechanisms of the offsets of explicit quadratic surfaces die to differential geometry properties lead to an understanding of the self-intersecting mechanisms of offsets of regular parametric surfaces. in this paper, we develop the equations of the self-intersection curves of an offset of an explicit quadratic surface. We also develop an algorithm to detect and trace a small loop of a self-intersection curve of an offset of a regular parametric surface based on our analysis of offsets of explicit quadratic surfaces. Examples illustrate our method.

    DOI

  • Robust interval algorithm for surface intersections

    CY Hu, T Maekawa, NM Patrikalakis, XZ Ye

    COMPUTER-AIDED DESIGN   29 ( 9 ) 617 - 627  1997.09  [Refereed]

     View Summary

    In this paper, we develop robust algorithms for computing interval polynomial curve-to-surface and surface-to-surface intersections. These include well-conditioned transversal intersections as well as ill-conditioned non-transversal intersections. Key components of our methods are the reduction of the intersection problems into solving balanced or unbalanced systems of non-linear interval polynomial equations. These systems are solved using an interval non-linear polynomial solver based on Bernstein subdivision coupled with rounded interval arithmetic, documented in a series of earlier papers. The solver provides results with numerical certainty and verifiability. Examples illustrate our techniques. We also provide a theoretical analysis of degenerate interval polynomial curve-to-surface and surface-to-surface ill-conditioned non-transversal intersections. (C) 1997 Elsevier Science Ltd.

  • Computation of self-intersections of offsets of Bezier surface patches

    T Maekawa, WJ Cho, NM Patrikalakis

    JOURNAL OF MECHANICAL DESIGN   119 ( 2 ) 275 - 283  1997.06  [Refereed]

     View Summary

    Self-intersection of offsets of regular Bezier surface patches due to local differential geometry and global distance function properties is investigated. The problem of computing starting points for tracing self-intersection curves of offsets is formulated in terms of a system of nonlinear polynomial equations and solved robustly by the interval projected polyhedron algorithm. Trivial solutions are excluded by evaluating the normal bounding pyramids of the surface subpatches mapped from the parameter boxes computed by the polynomial solver with a coarse tolerance. A technique to detect and trace self-intersection curve loops in the parameter domain is also discussed. The method has been successfully tested in tracing complex self-intersection curves of offsets of Bezier surface patches. Examples illustrate the principal features and robustness characteristics of the method.

  • Robust interval algorithm for curve intersections

    CY Hu, T Maekawa, EC Sherbrooke, NM Patrikalakis

    COMPUTER-AIDED DESIGN   28 ( 6-7 ) 495 - 506  1996.06  [Refereed]

     View Summary

    In this paper, we develop and study a robust algorithm for computing intersections of two planar interval polynomial curves. The intersection problems include well-conditioned transveral intersections as well as ill-conditioned cases such as tangential and overlapping intersections. Key components of our methods are the reduction of the intersection problems into solving systems of nonlinear interval polynomial equations which consist of m equations with n unknowns. An earlier interval nonlinear polynomial solver for balanced system based on Bernstein subdivision method coupled with rounded interval arithmetic is extended to solve unbalanced systems. The solver provides results with numerical certainty and verifiability. Examples illustrate our techniques. Copyright (C) 1996 Elsevier Science Ltd

  • Towards robust geometric modelers, 1994 Progress Report

    NM Patrikalakis, W Cho, CY Hu, T Maekawa, EC Sherbrooke, J Zhou

    PROCEEDINGS OF THE 1995 NSF DESIGN AND MANUFACTURING GRANTEES CONFERENCE     139 - 140  1994  [Refereed]

  • COMPUTATION OF SINGULARITIES AND INTERSECTIONS OF OFFSETS OF PLANAR CURVES

    T MAEKAWA, NM PATRIKALAKIS

    COMPUTER AIDED GEOMETRIC DESIGN   10 ( 5 ) 407 - 429  1993.10  [Refereed]

     View Summary

    The objective of this paper is to compute the singularities of a normal offset of a planar integral polynomial curve and the intersections of two specific normal offsets of two planar integral polynomial curves. Singularities include irregular points (such as isolated points and cusps) and self-intersections. The key element in the above techniques is the computation of all real roots within a finite box of systems of nonlinear equations involving polynomials and square roots of polynomials. The curves that we are investigating are described by polynomial functions, but their offset curve representations involve polynomials and square roots of polynomials. A methodology based on adaptive subdivision techniques to solve the resulting systems of nonlinear equations is investigated. Key components of our methods are the reduction of the problems into solutions of systems of polynomial equations of higher dimensionality through the introduction of auxiliary variables and the use of rounded interval arithmetic in the context of Bernstein subdivision to enhance the robustness of floating point implementation. Examples illustrate our techniques.

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Books and Other Publications

  • Shape Interrogation for Computer Aided Design and Manufacturing

    MAEKAWA Takashi( Part: Joint author)

    Springer-Verlag  2002.02

  • Handbook of Computer Aided Geometric Design Chapter 25 Intersection Problems

    ( Part: Joint author)

    Elsevier Science Publisher  2002

Misc

  • 2415 B-spline volume interpolation of discrete data by iterative geometric algorithm

    SASAKI Yuhi, TAKEZAWA Masahito, KIM Seungki, MAEKAWA Takashi

      2014 ( 24 ) "2415 - 1"-"2415-5"  2014.09

     View Summary

    In the past, tremendous amount of research has been conducted to fit point clouds using B-spline curves and surfaces. However, there are few studies on fitting scientific volume data using the trivariate B-spline functions. In this paper, an iterative geometric approximation method, which iteratively repositions B-spline control points on the basis of geometrical rules, is introduced to fit the scientific volume data.

    CiNii

  • Reconstruction of complex objects from multiple photographic images using LEGO blocks

    Hui Lin, Takashi Maekawa

    IPSJ SIG Notes. CVIM   2013 ( 9 ) 1 - 6  2013.11

     View Summary

    We introduce a system to reconstruct LEGO models from multiple two-dimensional images of complex objects taken from different views. We employ a unit voxel with edge length ratios 5:5:6 for the Shape from silhouette method, and convert the resulting voxel models with color information to LEGO sculptures. In order to minimize the number of LEGO blocks, we remove inside voxels as much as possible before the conversion so that the thickness of the voxel model is uniform from the surface voxels.

    CiNii

  • 2113 Accurate Reconstruction of 2.5D Objects by Photometric Stereo

    YAMAURA Yusuke, NANYA Takaki, IMOTO Harutaka, MAEKAWS Takashi

      2013 ( 23 ) "2113 - 1"-"2113-6"  2013.10

     View Summary

    This paper studies the recovery of the height field function of an object from its surface normal vectors in terms of uniform bi-quadratic B-spline surfaces. Our mathematical formulation for explicit surface reconstruction is based on differential geometry and geometric modeling techniques. Complex examples are provided to demonstrate the effectiveness of the proposed method.

    CiNii

  • 3307 Constrained B-spline surface fitting by iterative geometric algorithm

    KINERI Yuki, MAEKAWA Takashi

      2012 ( 22 ) "3307 - 1"-"3307-8"  2012.09

     View Summary

    Recently, the advancement of the laser range scanner has made it possible to provide dense and accurate range data of 3D objects. From these point clouds, one can reconstruct a CAD model of the existing old mechanical parts, which is called reverse engineering. However, if we fit the point cloud without any constraints on geometric characteristics, these features will be easily lost on the reconstructed surface. In this paper we introduce novel methods to impose geometric constraints on the B-spline approximants during the iterative geometric fitting process. The geometric constraints include reflectional symmetry of the surfaces of industrial products and feature curves on the aesthetic surfaces provided by designers.

    CiNii

  • 2111 Computer Aided Design of Highways Based on Differential Geometry of Space Curves

    Suzuki Junya, Maekawa Takashi

      2011 ( 21 ) 176 - 179  2011.10

     View Summary

    In the current highway design, a center curve of a highway is designed in three steps. In the first step the projection of the center curve onto the horizontal plane is designed with planar curves, i.e. x=x(t), y=y(t) consisting of straight lines, circular arcs, and clothoid curves. Secondly, the elevation z=z(t) is designed separately. Finally, the super elevation, which is the tilting of the road to account for the centripetal forces as the vehicle goes around a curve, is considered. Therefore, the resulting 3D curve may pass through the desired positions and tangents, however, in general, it does not have the correct normal and binormal vectors. In this research, we introduce a new method to generate the center curve with correct positions, tangents and curvature vectors at the input positions. Then, the section curves are generated along the normal vector at each input position, and blended together to form a lofted surface.

    CiNii

  • 2112 Topologically Robust Mesh Generation from Point Clouds Using Level Set Methods

    Yoshihara Hiroki, Yoshii Tatsuya, Shibutani Tadahiro, Maekawa Takashi

      2011 ( 21 ) 180 - 185  2011.10

     View Summary

    In this paper, we propose a novel method for approximating a set of scattered data points by a quadrilateral mesh using level set methods followed by geometric algorithms. The level set method is used to capture the topology of the point clouds, and the geometric algorithm using Catmull-Clark subdivision surface is employed to generate high quality meshes. Finally the Catmull-Clark control mesh is converted to B-spline representation. The reconstructed models of topologically complex models show the effectiveness of the proposed algorithm.

    CiNii

  • Extraction of Fingerprints from Free-Form Objects

    MAEKAWA Takashi

    Journal of Japan Society for Design Engineering   39 ( 12 ) 648 - 652  2004.12

    CiNii

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Industrial Property Rights

  • 「曲面生成装置および曲面生成用プログラム」

    土江庄一, 前川 卓

    Patent

  • 運搬車両の管制システム及び運搬車両の管理方法

    前川卓, 鈴木健稔, 宇佐美陸, 小橋裕司, 竹田幸司, 田貫富和

    Patent

  • 「軌道算出プログラム、加工装置、及び、軌道算出方法」

    前川 卓

    Patent

  • 目的面形状物製造方法、目的面形状物製造装置、部材形状取得装置およびプログラム

    前川 卓, 竹澤 正仁

    Patent

  • 「除去部分設定装置、曲面形成装置、除去部分設定方法、曲面形成方法およびプログラム」

    前川 卓, 村富 洋一, 竹澤 正仁

    Patent

  • 補間処理方法および補間処理装置

    特許第4934789号

    前川 卓, 松本泰典, 並木謙

    Patent

     View Summary

    単線形システムを解かずに純な幾何処理により点群を補間して高品質な曲面を生成する方法。

  • 形状評価方法、形状評価装置、及び形状評価装置を備えた装置

    特許第4876256号

    前川 卓, 西村 遥, 佐々木孝行

    Patent

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Awards

  • The Best Paper Award 1st Place

    2021.09   Solid Modeling Association SPM 2021  

    Winner: Felix Scholz, Takashi Maekawa

  • 貢献賞

    2019.09   日本機械学会 設計工学・システム部門  

    Winner: 前川 卓

  • 発明表彰

    2019.05   横浜国立大学  

    Winner: 前川 卓

  • 120周年記念功労者表彰

    2017.11   日本機械学会  

    Winner: 前川 卓

  • 特別研究員等の書面審査 表彰

    2016.08   日本学術振興協会  

    Winner: 前川 卓

  • 設計・システム部門 業績賞

    2014.09   日本機械学会  

    Winner: 前川 卓

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Research Projects

  • 炭素繊維刺しゅう機によるCFRP自由曲面成形方法の開発と応用

    日本学術振興会  科学研究費助成事業 基盤研究(B)

    Project Year :

    2018.04
    -
    2021.03
     

    前川 卓, 松尾 宏平, 澁谷 忠弘, 竹澤 正仁

     View Summary

    1)曲面を伸ばしたり切込みを入れたりせずに、曲げ変形のみで平面に展開できる曲面を可展面という。可展面のガウス曲率はゼロであることから、ガウス曲率がゼロに近い値を取る領域では曲率線を止め、基布に無駄な切込みを抑えるようにすることにより、切込み量の少ないガラスクロス基布を作成することができた。
    2)プリフォームの基布上に炭素繊維束を刺しゅうするための一筆書きツールパスを生成する基礎アルゴリズムを開発した。開発手法を自動車フード曲面に適用することで、平面展開図上において1本で繋がったツールパスを生成することができた。また生成したツールパスCADデータを刺しゅう機に適したデータ形式に変換して入力することで、生成したツールパスに沿って炭素繊維束をプリフォーム基布上に縫い付けることができた。
    3)改良型曲率線展開法で展開した短冊状の基材を張り合わせることで曲面を有する製品形状を再構築できることを利用して、設計形状の雌型を必要としない新たなCFRP成形手法の実用化に向けて開発を開始した。本年度は、プリフォームに比較的剛性の高いガラスロービングクロスを用いて成形試験を行うことで、より実用的な成形が可能であることを示した。しかし成形中の自重による変形、ならびに成形後の製品表面の平滑性については改善する必要がありこれらの課題について、引き続き取り組む。
    4)数値シミュレーションを通してその妥当性を検証した。標準的なプロペラを対象に、モード解析と静解析を実施して、炭素繊維による効率的な強化方法について検討した。炭素繊維を任意の曲線に沿って配置することで、より軽量かつ高強度なプロペラ構造が期待できる。また、主応力分布をもとに炭素繊維の配置を決定するための試行として、ボンネットのシェル要素モデルを対象に主応力分布から応力線を作成するための基礎検討を行った。

  • 曲率線展開法に基づくCFRP成形技術の開発と応用

    日本学術振興会  科学研究費助成事業

    Project Year :

    2015.04
    -
    2018.03
     

    前川 卓

     View Summary

    地球の温暖化に伴い、今後CO2排出量の規制強化がますます進むと予測される中、自動車、航空機、船舶等日常的に使用される乗り物の軽量化は、CO2排出量の削減に直接的に大きく貢献することができる。このような背景の中、炭素繊維強化プラスチック(CFRP)は鉄と比較して高価ではあるものの、重さが約4分の1、強度が10倍の高機能材料であり、鉄の代替材料として注目を集めている。その中でもとりわけ、自動車、航空機の翼と胴体とのブレンド曲面、新幹線のノーズ、船舶のプロペラ、ハル等の形状は意匠性や流体力学特性を満たさなければならない複雑な曲面をしており、各層毎のCFRPの切り込みをどのように決めれば高強度でかつ、仕上げ工程の少ない製品に仕上がるのかという統一された基準がない。本研究ではこれらの複雑な曲面に曲率線展開法に基づいた新たな成形加工方法を適用することにより様々なCFRP曲面を作製し、その用途に応じた強度試験や数値シミュレーションを通

  • 幾何処理による曲面曲率コントロールとそのIsogeometric解析への応用

    日本学術振興会  科学研究費助成事業

    Project Year :

    2012.04
    -
    2015.03
     

    前川卓

  • 幾何処理による点群の位置並びに法線ベクトルのフィッティング

    日本学術振興会  科学研究費助成事業

    Project Year :

    2008.04
    -
    2011.03
     

    前川 卓

  • ポリゴンメッシュで形成された3次元ソリッドモデルの電子指紋に関する研究

    日本学術振興会  科学研究費助成事業

    Project Year :

    2004.04
    -
    2007.03
     

    前川 卓

Presentations

  • 掘削面に対する油圧ショベル作業具正対手法に関する研究

    佐藤 隆人, 前川 卓

    第 26 回設計工学・システム部門講演会  (慶應義塾大学 日吉キャンパス)  日本機械学会

    Presentation date: 2016.10

  • From CAD Models to Toy Brick Sculptures: A 3D Block Printer

    Y. Maeda, O. Nakano, T. Maekawa, S. Maruo

    RSJ International Conference on Intelligent Robots and Systems (IROS)  (Daejeon, Korea)  2016 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)

    Presentation date: 2016.10

  • 法線マップ直接編集による流線型形状曲面の設計

    蓼沼 周, 前川 卓  [Invited]

    情報処理学会 グラフィクスとCAD研究会 

    Presentation date: 2015.11

  • 自立性と安定性を考慮したレゴモデル組み立て図の自動生成

    狐崎 拓哉, 竹澤 正仁, 佐々木 雄飛, 前川 卓  [Invited]

    情報処理学会 グラフィクスとCAD研究会 

    Presentation date: 2015.11

  • 照度差ステレオ法を用いた検査システムの開発

    町田賢一郎, 井本治孝, 前川卓  [Invited]

    第 25 回設計工学・システム部門講演会 

    Presentation date: 2015.09

  • 照度差ステレオ法を用いた3次元物体の復元

    蓼沼 周, 井本治孝, 町田 賢一郎, 前川 卓  [Invited]

    第 25 回設計工学・システム部門講演会 

    Presentation date: 2015.09

  • 曲率線展開法に基づく自由曲面を有するペーパークラフトの作成方法

    竹澤正仁, 佐藤隆人, 前川卓  [Invited]

    第 25 回設計工学・システム部門講演会 

    Presentation date: 2015.09

  • Isogeometric 解析による前縁半径をパラメータとした二次元翼周りの流体解析

    志田 健太朗, 遠藤 修平, 蓼沼 周, 前川 卓  [Invited]

    第 25 回設計工学・システム部門講演会  (信州大学工学部) 

    Presentation date: 2015.09

  • 幾何処理によるB-SPLINE VOLUME フィッティングとその可視化

    金 勝基, 佐々木 雄飛, 竹澤 正仁, 前川 卓  [Invited]

    関東学生会第54回学生員卒業研究発表講演会  日本機械学会

    Presentation date: 2015.03

  • 波形管軸圧縮時に波形曲率が最大応力に及ぼす影響の研究

    今井 琢麻, 熊谷 盛徳, 前川 卓  [Invited]

    関東学生会第54回学生員卒業研究発表講演会  (波形管軸圧縮時に波形曲率が最大応力に及ぼす影響の研究)  日本機械学会

    Presentation date: 2015.03

  • 組み立てやすさを考慮したレゴブロックモデルによる複雑な物体の再構築

    狐崎 拓哉, 前川 卓  [Invited]

    関東支部第21期総会・講演会  日本機械学会

    Presentation date: 2015.03

  • 微分幾何学に基づくNACA 翼型形状のB-spline 曲線による近似方法

    蓼沼 周, 遠藤 修平, 前川 卓  [Invited]

    関東学生会第53回学生員卒業研究発表講演会 

    Presentation date: 2015.03

  • 露天掘り鉱山の形状設計

    狐崎 拓哉, 安里 翼, 前川 卓

    第 24 回設計工学・システム部門講演会  日本機械学会

    Presentation date: 2014.09

  • 幾何処理による離散データの B-spline volume 補間

    佐々木 雄飛, 竹澤 正仁, 金 勝基, 前川 卓

    第 24 回設計工学・システム部門講演会  日本機械学会

    Presentation date: 2014.09

  • 複雑な物体の複数画像からのレゴブロックによる再構築

    林慧, 前川卓

    情報処理学会研究報告グラフィクスとCAD (第153回グラフィクスとCAD研究発表会) 

    Presentation date: 2013.11

  • 照度差ステレオを用いた2.5D物体の高精度復元

    山浦 佑介, 南谷 崇輝, 井本 治孝, 前川 卓

    第23回設計工学・システム部門講演会 

    Presentation date: 2013.10

  • 鉱山における3D-GEO Map生成

    小橋 裕司, 前川 卓

    第23回設計工学・システム部門講演会 

    Presentation date: 2013.10

  • 美的曲線を取り入れた意匠曲面の曲率コントロール

    遠藤 修平, 前川 卓

    第23回設計工学・システム部門講演会 

    Presentation date: 2013.10

  • Isogeometric解析用 3D NURBSソリッドの生成方法

    チャン ダン ティエン, 前川 卓

    第23回設計工学・システム部門講演会  (沖縄県読谷村)  日本機械学会

    Presentation date: 2013.10

  • Constrained B-spline Surface Fitting by Iterative Geometric Approximation Algorithm

    Y. Kineri, W. Choi, T. Maekawa

    ACDDE2012, Niseko Japan, December 2012 

    Presentation date: 2012.12

  • 幾何アルゴリズムによる拘束条件付きB-spline曲面フィッティング

    木練 佑樹, 前川 卓

    第22回設計工学・システム部門講演会 

    Presentation date: 2012.09

  • ボクセルの統合を用いた,複雑なモデルのリバースエンジニアリング

    南谷 崇輝, 吉原 宏貴, 前川 卓

    第22回設計工学・システム部門講演会 

    Presentation date: 2012.09

  • コンピュータビジョンによるマイクロ製品の形状評価方法

    末安 秀匡, 前川 卓

    第146回グラフィクスとCAD研究発表会 

    Presentation date: 2012.02

  • SFS法と合焦判定法を用いたマイクロ製品形状評価

    末安 秀匡, 前川 卓

    Presentation date: 2011.12

  • レベルセット法による点群からの位相頑強なメッシュ生成

    吉原 宏貴, 吉井 達哉, 澁谷 忠弘, 前川 卓

    日本機械学会 第21回設計工学・システム部門講演会 

    Presentation date: 2011.10

  • 空間曲線の微分幾何学に基づく高速道路のコンピュータ支援設計

    鈴木 絢也, 前川 卓

    日本機械学会 第21回設計工学・システム部門講演会 

    Presentation date: 2011.10

  • B-splineにより曲率が精確に表現されているシェルモデルのisogeometric 解析

    穆 凱圓, 澁谷 忠弘, 松井 和己, 前川 卓

    日本機械学会 第21回設計工学・システム部門講演会 

    Presentation date: 2011.10

  • ボクセルの統合による3 次元物体の全体形状復元

    南谷 崇輝, 篤 幸太郎, 末安 秀匡, 前川 卓

    Visual Computing / グラフィクスとCAD 合同シンポジウム 

    Presentation date: 2011

  • 三角形メッシュの主曲率と主効率方向の計算方法

    岡庭翔一, 前川 卓

    日本機械学会 第20回設計工学・システム部門講演会 

    Presentation date: 2010.10

  • 高速化された幾何アルゴリズムによるB-spline曲面近似

    良知 鷹彦, 王 銘思, 前川 卓

    日本機械学会 第20回設計工学・システム部門講演会 

    Presentation date: 2010.10

  • レベルセット法による三次元モデルの再構築

    金 東俊, 良知 鷹彦, 三橋 郁, 澁谷 忠弘, 前川 卓

    日本機械学会 レベルセット法による三次元モデルの再構築 

    Presentation date: 2010.03

  • レベルセット法と幾何アルゴリズムを用いた点群からのポリゴンメッシュ生成

    金 東俊, 良知 鷹彦, 安藤 嘉章, 澁谷 忠弘, 前川 卓

    Visual Computing / グラフィクスとCAD 合同シンポジウム 

    Presentation date: 2010

  • 幾何処理と線形解法による細分割曲面補間の比較

    安藤 嘉章, 岡庭 翔一, 前川 卓

    日本機械学会 第19回設計工学・システム部門講演会 

    Presentation date: 2009.10

  • 幾何処理によるB-spline曲線・曲面補間の高速化

    町田 賢一郎, 良知 鷹彦, 前川 卓

    日本機械学会 第19回設計工学・システム部門講演会 

    Presentation date: 2009.10

  • SFS法を用いたマイクロ製品評価方法

    船山裕輔, 篤 幸太郎, 前川卓

    Visual Computing /グラフィクスとCAD 合同シンポジウム 

    Presentation date: 2009

  • B-spline曲線による無人車両の準最適走行経路生成

    田村 重文, 尾崎 友紀, 野田哲也, 前川 卓

    日本機械学会 第18回設計工学・システム部門講演会 

    Presentation date: 2008.09

  • 膨大な点群からなる形状の細分割曲面近似

    森岡真之, 西山 悠, 前川 卓

    日本機械学会 第18回設計工学・システム部門講演会 

    Presentation date: 2008.09

  • 視体積交差法を用いた3D-CADモデルの作成

    船山裕輔, 平野大輔, 前川 卓

    日本機械学会 第18回設計工学・システム部門講演会 

    Presentation date: 2008.09

  • マイクロ製品の3次元形状評価方法

    船山 裕輔, 平野 大輔, 前川 卓

    日本機械学会 2008年度年次大会講演会 

    Presentation date: 2008.08

  • 幾何処理によるB-スプラインフィッティング

    呉服 秀一, 田村 重文, 梶原 健, 前川 卓

    日本機械学会 第17回設計工学・システム部門講演会 

    Presentation date: 2007.11

  • 視体積交差法による三次元モデル復元装置

    安倍 史朗, 平野 大輔, 船山 裕輔, 前川 卓

    日本機械学会 第17回設計工学・システム部門講演会 

    Presentation date: 2007.11

  • 幾何アルゴリズムによる区分平滑曲面補間

    宮崎 達矢, 西山 悠, 前川 卓

    日本機械学会 第17回設計工学・システム部門講演会 

    Presentation date: 2007.11

  • 幾何処理による細分割曲面補間

    並木 謙, 松本 泰典, 前川 卓

    日本機械学会 第16回設計工学・システム部門講演会 

    Presentation date: 2006.11

  • 幾何処理によるB-spline補間

    樋口 文隆, 呉服 秀一, 前川 卓

    日本機械学会 第16回設計工学・システム部門講演会 

    Presentation date: 2006.11

  • 円形ハイライト線によるB-Spline曲面のフェアリング

    西山 悠, 前川 卓

    日本機械学会 第16回設計工学・システム部門講演会 

    Presentation date: 2006.11

  • タービンブレードの線切削加工における工具経路の算出方法

    平野 大輔, 前川 卓

    日本機械学会 関東学生会第45回学生員卒業研究発表講演会 

    Presentation date: 2006.03

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Teaching Experience

  • 応用機械設計製図II

    横浜国立大学  

  • 設計統合CAD

    横浜国立大学  

  • 設計と加工

    横浜国立大学  

  • 機械設計 I

    横浜国立大学  

  • 機構学Ⅰ

    横浜国立大学  

  • 機械要素設計製図Ⅱ

    横浜国立大学  

  • 機械要素設計製図Ⅰ

    横浜国立大学  

  • 機械要素設計・製図Ⅱ

    横浜国立大学  

  • 機械要素設計・製図Ⅰ

    横浜国立大学  

  • 設計統合CAD

    横浜国立大学  

  • 機構学

    横浜国立大学  

  • 機械設計Ⅱ

    横浜国立大学  

  • 機械設計Ⅰ

    横浜国立大学  

  • 形状処理特論

    横浜国立大学  

▼display all

 

Committee Memberships

  • 2012.03
    -
    Now

    Computer-Aided Design  Editor

Social Activities

  • Rhinocerosによる3次元CAD理論入門

    工学研究院  (横浜国立大学田町サテライトキャンパス) 

    2006.09
    -
     

     View Summary

    3次元CADソフトRhinocerosを使って製品設計を行う際の曲線・曲面理論の基礎知識を習得し、演習や実際の応用事例を通して理解を深める。

  • Rhinocerosによる3次元CAD理論入門

    工学研究院  (横浜国立大学田町サテライトキャンパス) 

    2005.09
    -
     

     View Summary

    3次元CADソフトRhinocerosを使って製品設計を行う際の曲線・曲面理論の基礎知識を習得し、演習や実際の応用事例を通して理解を深める。