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Keigo Watanabe - One of the best experts on this subject based on the ideXlab platform.

  • Vibrational motion Control for foamed polystyrene machining robot and extraction of radius of curvature for fuzzy Feed Rate Control
    Artificial Life and Robotics, 2015
    Co-Authors: Fusaomi Nagata, Maki K. Habib, Akimasa Otsuka, Shohei Hayashi, Tomoya Nagatomi, Keigo Watanabe
    Abstract:

    There are two serious requirements to machining systems used in manufacturing industries. They are machining quality and efficiency. In this paper, a vibrational motion Control is proposed for an endmill attached to the tip of a machining robot to suppress the occurrence of undesirable cusp marks. In addition, the calculation of radius of curvature along discrete CL data is introduced for a fuzzy Feed Rate Controller which can regulate the tangent velocity. The radius of curvature is effective information as a fuzzy input. The effectiveness of the proposed methods is validated through experiments.

  • Feed-Rate Control using fuzzy reasoning for NC machine tools
    Artificial Life and Robotics, 2008
    Co-Authors: Fusaomi Nagata, Keigo Watanabe
    Abstract:

    In this article, a 3D design and machining system based on an NC machine tool with a rotary unit is first introduced to effectively produce attractive paint rollers. A post-processor is proposed to transform a base tool path called cutter location data (CL data) to NC data, mapping the y -directional pick Feed to the rotational angle of the rotary unit. The 3D machining system with the postprocessor allows us easily to transcribe a relief design on a flat model surface to a cylindrical model surface. The postprocessor has another function that systematically adjusts the Feed-Rate according to the curvature of each design to prevent the machined surface from being chipped. The post-processor geneRates suitable Feed-Rate codes by using a simple fuzzy reasoning method while checking the edges in relief designs. Experimental results show that wooden paint rollers with attractive relief designs can be successfully machined without undesirable edge chipping. Next, the proposed fuzzy Feed-Rate generator is further applied to a mold-polishing robot, so that the polishing time can be reduced by about 30% compared with the case without the generator.

  • Feed Rate Control Using Fuzzy Reasoning for a Mold Polishing Robot
    Journal of Robotics and Mechatronics, 2006
    Co-Authors: Fusaomi Nagata, Keigo Watanabe
    Abstract:

    Reducing time cost of polishing process is a major issue in metallic mold manufacturing. The Feed Rate, i.e., tangential velocity, of a polishing robot is generally limited to maintain stable contact with workpieces having a large curvature. We propose a Feed Rate generator using fuzzy reasoning for polishing robots that regulates the Feed Rate along free-formed surfaces appropriately. The smaller the curvature of the model designed by a 3D CAD, the larger the distance between two adjacent cutter location data (CL data) steps geneRated by the main processor of CAM. Therefore, given curvature results in acquiring the distance between two adjacent steps of CL data. We also propose a hybrid position/force Controller with the Feed Rate generator enabling the robot to conduct polishing efficiently. Experiments show promising results.

Yoshimi Takeuchi - One of the best experts on this subject based on the ideXlab platform.

  • study on post processor for 5 axis Control machining centers in case of spindle tilting type and table spindle tilting type
    Journal of The Japan Society for Precision Engineering, 1994
    Co-Authors: Yoshimi Takeuchi, Kazuhiro Wada, T. Hisaki, Makoto Yokoyama
    Abstract:

    In order to make use of 5-axis Control machining centers, the post-processor plays an important role, which converts collision-free CL data, geneRated by the main-processor, to actual NC data. The difficulty of developing the post-processor lies in the diversity of the structure of 5-axis Control machining centers. The structure of 5-axis Control machining centers can be classified into three types, that is, table-tilting type, spindle-tilting type and table/ spindle-tilting type. The study especially deals with the development of the post-processor concerning spindletilting type and table/spindle-tilting type 5-axis Control machining centers, taking account of linearization, Feed Rate Control and spindle rotation Control. The validity of the post-processor developed in the study is experimentally confirmed.

  • study on post processor for 5 axis Control machining centers
    Journal of The Japan Society for Precision Engineering, 1992
    Co-Authors: Yoshimi Takeuchi, Takahiro Watanabe
    Abstract:

    The study deals with the general method of generating NC data from collision-free tool path of 5-axis Control machining centers. The use of 5-axis Control machining centers, capable of machining complicated workpiece shapes efficiently and accuRately, is recently increased. Then, it is inevitable to geneRate collision-free CL data and NC data rapidly. CL data are geneRated by the main-processor having the collision avoidance procedure between a workpiece and an arbitrary tool shape, based on the solid modeling technique. The post-processor developed in the study can convert CL data to actual NC data, taking account of the structure of machining centers, linearization, Feed Rate Control and spindle rotation Control. The main- and post-processors are experimentally found effective.

Makoto Yokoyama - One of the best experts on this subject based on the ideXlab platform.

Ming-yang Cheng - One of the best experts on this subject based on the ideXlab platform.

  • High-speed contouring Control with NURBS-based C^2 PH spline curves
    The International Journal of Advanced Manufacturing Technology, 2010
    Co-Authors: Javad Jahanpour, Mi-ching Tsai, Ming-yang Cheng
    Abstract:

    This paper presents a C^2 Pythagorean hodograph (PH) spline curve constructed by the non-uniform rational B-spline (NURBS) curve for high-speed contouring Control. With the knot vector, weights, and Control points given, the C^2 PH spline curve is defined to be a “good” interpolant for Hermit data obtained from a NURBS curve of degree 3 specified by the same Control polygon, weights, and the knot vector. To this end, the first- and second-order derivatives are evaluated at the nodal points on the NURBS curve. These boundary conditions are imposed on the PH segments of degree 9 to preserve continuity between the connecting segments. The S-curve motion planning architecture with variable Feed Rate for a planar NURBS-based C^2 PH spline curve is also developed in this paper. In particular, C^1 cubic Feed acceleration/deceleration is imposed on the first and last PH segments. Several NURBS-based C^2 PH spline curve-following tasks were conducted to verify the effectiveness of the proposed interpolation algorithm. Experimental results show that the proposed interpolator is not only feasible for machining the complicated parametric curves represented in the NURBS-based C^2 PH spline form but also yields satisfactory contouring performance under variable Feed Rate Control.

  • High-speed contouring Control with NURBS-based C2 PH spline curves
    The International Journal of Advanced Manufacturing Technology, 2009
    Co-Authors: Javad Jahanpour, Mi-ching Tsai, Ming-yang Cheng
    Abstract:

    This paper presents a C2 Pythagorean hodograph (PH) spline curve constructed by the non-uniform rational B-spline (NURBS) curve for high-speed contouring Control. With the knot vector, weights, and Control points given, the C2 PH spline curve is defined to be a “good” interpolant for Hermit data obtained from a NURBS curve of degree 3 specified by the same Control polygon, weights, and the knot vector. To this end, the first- and second-order derivatives are evaluated at the nodal points on the NURBS curve. These boundary conditions are imposed on the PH segments of degree 9 to preserve continuity between the connecting segments. The S-curve motion planning architecture with variable Feed Rate for a planar NURBS-based C2 PH spline curve is also developed in this paper. In particular, C1 cubic Feed acceleration/deceleration is imposed on the first and last PH segments. Several NURBS-based C2 PH spline curve-following tasks were conducted to verify the effectiveness of the proposed interpolation algorithm. Experimental results show that the proposed interpolator is not only feasible for machining the complicated parametric curves represented in the NURBS-based C2 PH spline form but also yields satisfactory contouring performance under variable Feed Rate Control.

Dmitry A Stepanenko - One of the best experts on this subject based on the ideXlab platform.

  • modeling of spraying with time dependent material Feed Rate
    Applied Mathematical Modelling, 2007
    Co-Authors: Dmitry A Stepanenko
    Abstract:

    This paper presents a mathematical model for predicting the thickness of coatings deposited by means of spraying onto rotating parts with circular symmetry, for the case of time-dependent material Feed Rate. A procedure for calculating the material Feed Rate Control law providing production of coatings with uniform thickness or coatings with a predefined law of thickness variation is developed. The proposed procedure was used to analyze the process of spraying onto the surface of a rotating disc. A material Feed Rate variation law providing production of uniform coatings and coatings with linear thickness variation is calculated. It is demonstRated that for the first case the optimal law of material Feed Rate variation is described by a linear function and for the second case it can be successfully approximated by a quadratic function. The proposed calculation technique can be easily used for the case of coatings with a more complex law of thickness variation.