Preview

Engineer

Powerful Essays
Open Document
Open Document
7636 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Engineer
September 3, 2012 NURBS CURVE MATHEMATICAL REPRESENTATION AND NURBS BASE INTERPOLATION TECHNIQUES FOR
CNC PROGRAMMING
Biruk Mamo Wodaj
Page 1 of 33
ABSTRACT
This term paper is prepared to partially fulfill a requirement of graduate studies program in industrial engineering for the course „FLEXIBLE MANUFACTURING SYSTEMS‟. The term paper studies on NURBS (Non-Uniform Rational B-Splines) curve Mathematical Representation and NURBS based Interpolations Techniques for CNC programming.
Because of its importance in both high-speed machining and tool-path generation, approximating a contour by NURBS format is a potential function in CAD/CAM/CNC systems. NURBS curve is one of the most commonly used tools in CAD systems and geometric modeling for its various specialties, which mean that its shape is locally adjustable as well as its continuity order and it, can represent a conic curve precisely.
Over the recent years, different curves and surface representation forms have been proposed. Currently, B-Splines and NURBS (Non-Uniform B-Splines ) are the most popular mathematical forms. NURBS offer a unified mathematical form not only for representation of free-form curves and surfaces but also for precise representation of close form shapes such as lines, conics, quadrics and surfaces of revolution.
In the following sections, there is an introduction, a detail analysis of NURBS mathematical representation and NURBS base interpolations techniques discussed. Finally the study provides a conclusion.
September 3, 2012 NURBS CURVE MATHEMATICAL REPRESENTATION AND NURBS BASE INTERPOLATION TECHNIQUES FOR
CNC PROGRAMMING
Biruk Mamo Wodaj
Page 2 of 33
ACKNOWLEDGMENT
I would like to deeply praise the Holy Lord, God for allowing me passing all of this moment; nothing is possible without you.
Special thanks are given to our instructor Dr. Tafesse Gebresenbet for the opportunity he provide in the preparation of a term paper about NURBS Curves Mathematical Representation and



References: 1. A LECTURE NOTE BY Dr. Tafesse Gebresenbet (FMS-AAiT) 2. Khairan Rajab; Knowledge Guided Non-Uniform Rational B-Spline (NURBS) for Supporting Design Intent in Computer Aided Design (CAD) Modeling, 2011. 3. Yuan L. Lai, Jian H. Chen, and Jui P. Hung; Development of Machinable Ellipses by NURBS Curves, World Academy of Science, Engineering and Technology 14 2008. 4. S¨oren Larsson, Johan Kjellander; Implementation of NURBS curves into theVARKON CAD system, 2003 5. http://en.wikipedia.org/wiki/Non-uniform_rational_B-spline 6. Suk-Hwan Suh, Seong Kyoon Kang, Dae-Hyuk Chung, Ian Stroud; Theory and Design Of CNC Systems, Springer –Verlag London Limited, 2008.

You May Also Find These Documents Helpful

  • Satisfactory Essays

    ‎In this section we illustrate the sign control chart using a set of data from Montgomery \cite{(2)} on the inside diameters of piston rings manufactured by a forging process based on the SRS and RSS schemes‎. ‎Forty samples‎, ‎each of size 5‎, ‎have been taken from this process‎. ‎All samples are combined such that we have 200 measurements of the inside diameters of the piston rings‎. ‎\\‎…

    • 358 Words
    • 2 Pages
    Satisfactory Essays
  • Satisfactory Essays

    A part programme is coded using coordinates to give a detailed set of directions to be read by the machine control unit and then followed by the machine tool. When creating a part programme, first of all the programmer must look at a detail drawing to tabulate coordinates and create an operation plan which will include a tool list and materials – this can all be very time consuming and can leave much room for error. Any incorrect code in a programme could lead to errors in the machined component, for example if a datum point is not set in the right place then only part of the component may be drilled/milled in the wrong place; errors in the finished component will mean the entire written programme will have to be thoroughly checked through again, which again is very long and mistakes in the code are not easily identified by the same person who wrote it. If the error is so small the fault in the part made may go unnoticed until put into the final assembly – leading to malfunction. A much more efficient approach to creating a programme would be for the programmer to create a CAD drawing which software such as CIMCO can use to generate a code all by itself. Simulation using CAD can be used for testing a design before letting the programme make it straight away, this makes for less redrafting and delays, therefore saving time. When sent a CAD drawing from a client, it would be quicker to open them using a software – like CIMCO – to generate a tool path for use immediately rather than using the CAD drawing with dimensions to print as a detail drawing to then tabulate etc. Complex shapes and tool paths such as curvy three dimensional designs (for example see figure 1) are much more achievable using 3D modelling because there may be need for more than one tool path at a time which would not be very fun to programme manually. There are some…

    • 509 Words
    • 2 Pages
    Satisfactory Essays
  • Good Essays

    A CAD model can quickly display an engineer’s ideas in a realistic way. And those models can be used to generate technical drawings that can communicate the information necessary to make the idea a reality. In order to generate a 3D model, designs must start with sketches that are generated within the CAD program. These computer generated sketches will appear resemble hand drawn sketches in geometry (the combination of points, lines, and shapes), but have big advantages over hand drawn sketches. One important difference between a freehand sketch and a CAD sketch is accuracy. The lines of a CAD sketch can be drawn perfectly straight, with start and end points that occur in exact locations in space. By using numeric (dimensional) constraints a line may also be given precise length, placed a specific distance from another sketch feature, or constrained to be oriented at a specific angle from another straight line. By applying geometric constraints a line can be made perfectly horizontal or vertical. If more than one line is being sketched, they can be made perfectly parallel or perpendicular, collinear, or equal in length. Lines can be constrained to be tangent to circles or arcs, and two circles can be constrained to be concentric. In order to precisely model a part, the designer must be able to use dimensional and geometric constraints within the CAD program.…

    • 453 Words
    • 2 Pages
    Good Essays
  • Satisfactory Essays

    Nt1330 Unit 3 Essay

    • 604 Words
    • 3 Pages

    I believe that the importance of correct programming and setting up of part is very important in today’s CNC manufacturing world as you are producing very precise components that need to be produced first time, every time or this is bad news for the company because of loss profits, scrap material and expensive repair costs. So ensuring correct programming and setting up of CNC machines is critical.…

    • 604 Words
    • 3 Pages
    Satisfactory Essays
  • Good Essays

    Throughout the semester, I have been working with Creo Parametric 1.0. This class has not only taught me a new 3D modeling program, but it has also taught me new ways to think about a design before I draw it. Each of the chapters, I have either enhanced something I already knew, or learned something new.…

    • 1142 Words
    • 5 Pages
    Good Essays
  • Good Essays

    Engineer

    • 1220 Words
    • 5 Pages

    There are always going to be challenges in teams but having a plan that will effectively address the challenges will help to mediate the severity of the challenges. If challenges are left alone and not addressed they can lead to team conflicts, misunderstandings, arguments, poor performance, project failures, resentment, and loss of motivation. As a team it is in its best interest to clearly set guidelines that will mitigate problems and reduce the risk of challenges the team may face. Before the team can set guidelines that address challenges that the majority of teams face the team must clearly define challenges that may lead to bigger problems within the team.…

    • 1220 Words
    • 5 Pages
    Good Essays
  • Best Essays

    Engineer

    • 2628 Words
    • 11 Pages

    Qantas is the world 2nd oldest airline founded in 1920. Qantas is widely recognized as the world 's leading long distance airline and one of the strongest brands in Australia.…

    • 2628 Words
    • 11 Pages
    Best Essays
  • Powerful Essays

    ABSTRACT Nowadays almost every industry needs fast processing power especially in engineering field. Manipulating high-resolution interactive graphics in engineering, such as in aircraft engine design, has always been a challenge in terms of performance and scalability because of the sheer volume of data involved.…

    • 4104 Words
    • 17 Pages
    Powerful Essays
  • Good Essays

    Loran and Shoran

    • 1233 Words
    • 5 Pages

    B is constant along each hyperbolic curve; when demarcated on a map, such curves are known as "TD…

    • 1233 Words
    • 5 Pages
    Good Essays
  • Good Essays

    Engineer

    • 17039 Words
    • 136 Pages

    Located in the State of California COMPREHENSIVE ANNUAL FINANCIAL REPORT FISCAL YEAR ENDED JUNE 30, 2013 LOUIS D. VAN MULLEM JR AIR POLLUTION CONTROL OFFICER MISSION STATEMENT Our mission is to protect the people and the environment of Santa Barbara County from the effects of air pollution. Front Cover: FACING NORTH FROM SANTA BARBARA SHORES COUNTY PARK (COURTESY OF DONALD KENDIG) Santa Barbara County Air Pollution Control District Located in the State of California Comprehensive Annual Financial Report…

    • 17039 Words
    • 136 Pages
    Good Essays
  • Powerful Essays

    y = ax2 + bx + c (a ≠ 0), is a parabola. In fact, coordinate geometry has been developed…

    • 4274 Words
    • 31 Pages
    Powerful Essays
  • Good Essays

    Autocad 2012 Tutorial

    • 3614 Words
    • 15 Pages

    The first true 3D computer model created on CAD systems in the late 1970s was the 3D wireframe model. Computer generated 3D wireframe models contain information about the locations of all the corners and edges in space coordinates. The 3D wireframe models can be viewed from any direction as needed and are in general reasonably good representations of 3D design. But because surface definition is not part of a wireframe model, all wireframe images have the inherent problem of ambiguity. For example, in the figure displayed below, which corner is in front, corner A or corner B? The ambiguity problem becomes much more serious with complex designs that have many edges and corners.…

    • 3614 Words
    • 15 Pages
    Good Essays
  • Powerful Essays

    CAD is an important industrial art extensively used in many applications, including automotive, shipbuilding, and aerospace industries, industrial and architectural design, prosthetics, and many more. CAD is also widely used to produce computer animation for special effects in movies, advertising and technical manuals. The modern ubiquity and power of computers means that even perfume bottles and shampoo dispensers are designed using techniques unheard of by engineers of the 1960s. Because of its enormous economic importance, CAD has been a major driving force for research in computational…

    • 2338 Words
    • 10 Pages
    Powerful Essays
  • Satisfactory Essays

    surface in space

    • 1497 Words
    • 6 Pages

    Permission required for reproduction or display. Slide 6 10.6 SURFACES IN SPACE EXAMPLE 6.3 Sketching an Ellipsoid Graph the ellipsoid Solution Draw the traces in the three coordinate planes: yz-plane (x = 0): xy-plane (z = 0): xz-plane (y = 0): © The McGraw-Hill Companies, Inc.…

    • 1497 Words
    • 6 Pages
    Satisfactory Essays
  • Powerful Essays

    Ans3 – The pencil is rotated in finger while drawing a long line in order to get a line of uniform thickness…

    • 5309 Words
    • 22 Pages
    Powerful Essays

Related Topics