Download or read book Precision CNC Machining of Free form Shapes Based on Analytical Real time Curve and Surface Interpolators written by Kevin M. Nittler and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Rational parametric geometry is utilized in its analytical form to solve computer-aided geometry, CNC machining, and motion control problems. The dissertation is broken into two parts: rational swept surfaces, and high-speed traversal of sharp corners. In Part I, a new class of swept surfaces is defined. The use of Pythagorean-hodograph (PH) polynomial sweep curves allows many geometrically intuitive sweep operations based on differential or integral properties of the sweep curve - such as the parametric speed, tangent, normal, curvature, arc length, and offset curves - to be used, while guaranteeing a rational surface compatible with the prevailing data types of CAD systems. A real-time surface interpolator is developed to machine this family of swept surfaces directly from their high-level procedural definitions. All the computations required for machining are performed in real time based on the exact surface geometry, including tool path planning, tool path interpolation, tool offsetting, and tool path step-over to achieve a prescribed scallop height. The surface interpolator offers profound accuracy and efficiency advantages over the traditional G-code approximation approach. For example, a 36,000-line piecewise-linear (G01) approximate part program file is replaced by a 3-line exact swept surface part program file. Physical examples are machined using an open-architecture CNC controller. In Part II, the problem of high-speed traversal of sharp tool path corners, within a prescribed geometrical tolerance is addressed. Each sharp corner is replaced by a quintic PH curve that meets the incoming/outgoing path segments with curvature continuity. The PH curve also permits a smooth modulation of feedrate around the corner by analytic reduction of the interpolation integral. To demonstrate this, real-time interpolator algorithms are developed for three model feedrate functions and incorporated into an open-architecture CNC controller. A global acceleration-limited approach to feedrate scheduling, including smooth deceleration and acceleration profiles along linear segments entering and leaving the rounded segments, is employed. Tests on a representative selection of tool paths yield substantial savings (up to 40%) in execution times, compared to the traditional "full stop" strategy for unmodified sharp corners.

Download or read book Real time CNC Interpolators for Precision Machining of Complex Shapes with Pythagorean hodograph Curves written by Yi-Feng Tsai and published by . This book was released on 2000 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Recent Advances in Manufacturing Modelling and Optimization written by Shailendra Kumar and published by Springer Nature. This book was released on 2022-04-21 with total page 830 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the selected proceedings of 2nd International Conference on Recent Advances in Manufacturing (RAM 2021). The book provides insights to current research trends and opportunities in modelling and optimization of manufacturing processes and systems. The topics covered include modelling analysis, computing and simulation, traditional and non-traditional optimization techniques, surface coating methods, additive manufacturing processes, CAD/CAM, robotics and automation, welding and joining processes, supply chain management and CAE and reverse engineering. This book will be a good reference for beginners, researchers and professionals interested in modelling and optimization related to manufacturing engineering and related fields.

Download or read book Advanced Intelligent Computing Theories and Applications With Aspects of Theoretical and Methodological Issues written by De-Shuang Huang and published by Springer. This book was released on 2008-09-08 with total page 1299 pages. Available in PDF, EPUB and Kindle. Book excerpt: The International Conference on Intelligent Computing (ICIC) was formed to p- vide an annual forum dedicated to the emerging and challenging topics in artificial intelligence, machine learning, bioinformatics, and computational biology, etc. It aims to bring together researchers and practitioners from both academia and ind- try to share ideas, problems and solutions related to the multifaceted aspects of intelligent computing. ICIC 2008, held in Shanghai, China, September 15–18, 2008, constituted the 4th International Conference on Intelligent Computing. It built upon the success of ICIC 2007, ICIC 2006 and ICIC 2005 held in Qingdao, Kunming and Hefei, China, 2007, 2006 and 2005, respectively. This year, the conference concentrated mainly on the theories and methodologies as well as the emerging applications of intelligent computing. Its aim was to unify the picture of contemporary intelligent computing techniques as an integral concept that highlights the trends in advanced computational intelligence and bridges theoretical research with applications. Therefore, the theme for this conference was “Emerging Intelligent Computing Technology and Applications”. Papers focusing on this theme were solicited, addressing theories, methodologies, and applications in science and technology.

Download or read book Piecewise Arc Length Parameterized NURBS Tool Paths Generation for 3 Axis CNC Machining of Accurate Smooth Sculptured Surfaces written by Maqsood Ahmed Khan and published by . This book was released on 2010 with total page 165 pages. Available in PDF, EPUB and Kindle. Book excerpt: In current industrial applications many engineering parts having complex shapes are designed using sculptured surfaces in CAD system. Due to the lack of smooth motions and accurate machining of these surfaces using standard linear and circular motions in conventional CNC machines, new commercial CNC systems are equipped with parametric curve interpolation function. However, in some applications these surfaces can be very complex that are susceptible to gouging and due to the approximation of; CL-path in CAM system and path parameter in real-time, high machining accuracy, smooth kinematic and feed-rate profiles, are difficult to achieve. This dissertation focuses on developing algorithms that generate tool paths in NURBS form for smooth, high speed and accurate sculptured surface machining. The first part of the research identifies and eliminates gouge cutter location (CL) point from the tool path. The proposed algorithm uses global optimization technique (Particle Swarm Optimization) to check all the CC-points along a tool-path with high accuracy, and only gouging free CC-points are used to generate the set of valid CL-points. Mathematical models have been developed and implemented to cover most of the cutter shapes, used in the industry. In the second phase of the research, all valid CL-points along the tool-path are used to generate CL-path in B-spline form. The main contribution of this part is to formulate an error function of the offset approximation and to represent it in NURBS form to globally bound the approximation errors. Based on this error function, an algorithm is proposed to generate tool-paths in B-spline from with; globally controlled accuracy, fewer control points and low function degree, compared to its contemporaries. The proposed approach thus presents an error-bounded method for B-spline curve approximation to the ideal CL-path within the accuracy. This part of research has two components, one is for 2 1/2- axis (pocket) and the other one is for 3-axis (surface) CNC machining. The third part deals with the problem of CL-path parameter estimation during machining in real time. Once the gouging free CL-path in NURBS form with globally controlled accuracy is produced, it is re-parameterized with approximate arc-length in the off-line stage. The main features of this work are; (1) sampling points and calculating their approximate arc-lengths within error bound by decomposing the input path into Bezier curve segments, (2) fitting the NURBS curve with approximate arc-length parameter to the sample points until the path and parameterization errors are within the tolerance, and (3) segment the curve into pieces with different feed rates if during machining the cutter trajectory errors are beyond the tolerance at highly curved regions in the NURBS tool path.

Download or read book Intelligent Robotics and Applications written by Caihua Xiong and published by Springer Science & Business Media. This book was released on 2008-09-29 with total page 1288 pages. Available in PDF, EPUB and Kindle. Book excerpt: This two volumes constitute the refereed proceedings of the First International Conference on Intelligent Robotics and Applications, ICIRA 2008, held in Wuhan, China, in October 2008. The 265 revised full papers presented were thoroughly reviewed and selected from 552 submissions; they are devoted but not limited to robot motion planning and manipulation; robot control; cognitive robotics; rehabilitation robotics; health care and artificial limb; robot learning; robot vision; human-machine interaction & coordination; mobile robotics; micro/nano mechanical systems; manufacturing automation; multi-axis surface machining; realworld applications.

Download or read book Real time Surface Interpolars for Multi axis CNC Machine Tools written by Rong-Shine Lin and published by . This book was released on 1994 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Real Time Scheme of Intelligent NURBS Interpolation for CNC Systems to Machine Sculptured Surfaces written by Fahad G. Ahmad and published by . This book was released on 2003 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ultraprecision Machining of Hybrid Freeform Surfaces Using Multiple Axis Diamond Turning written by Dennis Wee Keong Neo and published by Springer. This book was released on 2017-04-24 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis focuses on producing hybrid freeform surfaces using an advanced diamond-turning process, understanding the generation of surface accuracies (form errors) and how the choice of cutting strategies affects these, as well as simplifying the complications of generating cutting paths for such freeform surfaces. The breakthroughs behind this thesis are the development of novel, multiple-axis, diamond turning techniques to overcome the limitations of conventional diamond turning processes, an analytical model to optimize the generation of ultraprecise freeform surfaces, and an add-on tool path processor for CAD/CAM software solutions. It appeals to researchers and scholars with a strong machining background who are interested in the field of manufacturing ultraprecise freeform surfaces or in the field of optimizing ultraprecision machining processes.

Download or read book The NURBS Book written by Les Piegl and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 650 pages. Available in PDF, EPUB and Kindle. Book excerpt: Until recently B-spline curves and surfaces (NURBS) were principally of interest to the computer aided design community, where they have become the standard for curve and surface description. Today we are seeing expanded use of NURBS in modeling objects for the visual arts, including the film and entertainment industries, art, and sculpture. NURBS are now also being used for modeling scenes for virtual reality applications. These applications are expected to increase. Consequently, it is quite appropriate for The.N'URBS Book to be part of the Monographs in Visual Communication Series. B-spline curves and surfaces have been an enduring element throughout my pro fessional life. The first edition of Mathematical Elements for Computer Graphics, published in 1972, was the first computer aided design/interactive computer graph ics textbook to contain material on B-splines. That material was obtained through the good graces of Bill Gordon and Louie Knapp while they were at Syracuse University. A paper of mine, presented during the Summer of 1977 at a Society of Naval Architects and Marine Engineers meeting on computer aided ship surface design, was arguably the first to examine the use of B-spline curves for ship design. For many, B-splines, rational B-splines, and NURBS have been a bit mysterious.

Download or read book Machining Impossible Shapes written by Gustav J. Olling and published by Springer. This book was released on 2013-03-20 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt: On November 9-11, 1998,85 participants, representing 17 countries, gathered in Aubum Hills, Michigan, at the Chrysler Tech Center, to attend a workshop "SSM'98" (or Sculptured Surface Machining '98) organized by IFIP Working Group 5.3. This was the first major workshop on sculptured surface machining since the CAM-I sponsored conference "Machining Impossible Surfaces" held in 1981. The purpose of the SSM'98 workshop, entitled "Machining Impossible Shapes", was to promote a cross-fertilization of ideas among three communities: industrial users, CAM software developers and academic researchers. There were 17 participants who were "industrial users", 15 represented CAM software developers, 4 were from the machine tool industry, with the remainder being academic researchers. The format of the meeting included 40 presentations in 9 sessions, 4 keynote speeches and a sufficient amount of time for informal discussion amongst the participants. One of the most valuable aspects of the workshop was the opportunity for participants to meet informally and to discuss their mutual interests. This led to two "participant organized" sessions on five axis machining and on machine tool controllers.

Download or read book Advanced Numerical Methods to Optimize Cutting Operations of Five Axis Milling Machines written by Stanislav S. Makhanov and published by Springer Science & Business Media. This book was released on 2007-04-18 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents new optimization algorithms designed to improve the efficiency of tool paths for five-axis NC machining of sculptured surfaces. The book covers both the structure of the SLAM problem in general and proposes a new extremely efficient approach. It can be used by undergraduate and graduate students and researchers in the field of NC machining and CAD/CAM as well as by corporate research groups for advanced optimization of cutting operations.

Download or read book Real time Manufacturing Control Strategies Based on Open architecture Systems and Precise CAD Geometry written by Jyothirmai Srinathu and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Three inter-related methodologies are developed to improve the accuracy and efficiency of manufacturing operations by exploiting exact CAD geometry to drive CNC machines through open-architecture controllers. The first is based on a real-time interpolator algorithm for the offset curve trimming and filling operations required to ensure continuous, gouge-free toolpaths in the machining of strongly-curved part shapes. Using the exact part shape to perform real-time tool radius compensation eliminates the need to rely on voluminous G code part programs that must be regenerated to accommodate a change of tool radius. The second project develops a feedrate modulation strategy to ensure accurate traversal of tangent discontinuities in trimmed offset paths, and to balance the competing effects of chip load variations and tool acceleration rates. Finally, the possibility of suppressing chip load variations by real-time modulation of spindle speeds at a constant tool feedrate is investigated, and the DC motor regulation required to achieve this spindle speed modulation is analyzed.

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2001 with total page 818 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Minimum Error Tool Path Generation Method and an Interpolator Design Technique for Ultra precision Multiaxis CNC Machining written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pythagorean Hodograph Curves Algebra and Geometry Inseparable written by Rida T Farouki and published by Springer Science & Business Media. This book was released on 2008-02-01 with total page 725 pages. Available in PDF, EPUB and Kindle. Book excerpt: By virtue of their special algebraic structures, Pythagorean-hodograph (PH) curves offer unique advantages for computer-aided design and manufacturing, robotics, motion control, path planning, computer graphics, animation, and related fields. This book offers a comprehensive and self-contained treatment of the mathematical theory of PH curves, including algorithms for their construction and examples of their practical applications. It emphasizes the interplay of ideas from algebra and geometry and their historical origins and includes many figures, worked examples, and detailed algorithm descriptions.

Download or read book Shape Interrogation for Computer Aided Design and Manufacturing written by Nicholas M. Patrikalakis and published by Springer Science & Business Media. This book was released on 2002-02-14 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shape interrogation is the process of extraction of information from a geometric model. It is a fundamental component of Computer Aided Design and Manufacturing (CAD/CAM) systems. The authors focus on shape interrogation of geometric models bounded by free-form surfaces. Free-form surfaces, also called sculptured surfaces, are widely used in the bodies of ships, automobiles and aircraft, which have both functionality and attractive shape requirements. Many electronic devices as well as consumer products are designed with aesthetic shapes, which involve free-form surfaces. This book provides the mathematical fundamentals as well as algorithms for various shape interrogation methods including nonlinear polynomial solvers, intersection problems, differential geometry of intersection curves, distance functions, curve and surface interrogation, umbilics and lines of curvature, geodesics, and offset curves and surfaces. This book will be of interest both to graduate students and professionals.