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Computer-aided manufacturing: Computer-aided manufacturing (CAM) is the use of computer-based software tools that assist engineers and machinists in manufacturing or prototyping product components. CAM is a programming tool that allows you to make 3D models using computer-aided design (CAD). CAM was first used in 1971 for car body design and tooling. Overview Traditionally, CAM has been considered as an NC programming tool wherein 3D models of components generated in CAD software are used to generate CNC code to drive numerical controlled machine tools. Although this remains the most common CAM function, CAM functions have expanded to integrate CAM more fully with CAD/CAM/CAE PLM solutions. Early Use of CAM The first commercial applications of CAM were in large companies in the automotive and aerospace industries for example UNISURF in 1971 at Renault (Bezier) for car body design and tooling. Historical Shortcomings Historically, CAM software was seen to have several shortcomings that necessitated an overly high level of involvement by skilled CNC machinists. CAM software would output code for the least capable machine, as each machine tool interpreter added on to the standard g-code set for increased flexibility. In some cases, such as improperly set up CAM software or specific tools, the CNC machine required manual editing before the program will run properly. None of these issues were so insurmountable that a thoughtful engineer could not overcome for prototyping or small production runs; G-Code is a simple language. In high production or high precision shops, a different set of problems were encountered where an experienced CNC machinist must both hand-code programs and run CAM software. Typical areas of concern: • • • •

High Speed Machining, including streamlining of tool paths Multi-function Machining 5 Axis Machining Ease of Use

Machining process Most machining progresses through four stages, each of which is implemented by a variety of basic and sophisticated strategies, depending on the material and the software available. The stages are:

Roughing This process begins with raw stock, known as billet, and cuts it very roughly to shape of the final model. In milling, the result often gives the appearance of terraces, because the strategy has taken advantage of the ability to cut the model horizontally. Common strategies are zig-zag clearing, offset clearing, plunge roughing, restroughing. Semi-finishing This process begins with a roughed part that unevenly approximates the model and cuts to within a fixed offset distance from the model. The semi-finishing pass must leave a small amount of material so the tool can cut accurately while finishing, but not so little that the tool and material deflect instead of shearing. Common strategies are raster passes, waterline passes, constant step-over passes, pencil milling. Finishing Finishing involves a slow pass across the material in very fine steps to produce the finished part. In finishing, the step between one pass and another is minimal. Feed rates are low and spindle speeds are raised to produce an accurate surface. Contour Milling In milling applications on hardware with five or more axes, a separate finishing process called contouring can be preformed. Instead of stepping down in fine-grained increments to approximate a surface, the workpiece is rotated to make the cutting surfaces of the tool tangent to the ideal part features. This produces an excellent surface finish with high dimensional accuracy. Areas of usage • • •

In mechanical engineering In machining In electronic design automation, CAM tools prepare printed circuit board (PCB) and integrated circuit design data for manufacturing.

Softwares of CAM: Delcam: Delcam is one of the world's leading suppliers of advanced CAD/CAM software product development solutions for the manufacturing industry. The company has grown steadily since being founded formally in 1977, after initial development work at Cambridge University, UK. It is now a global developer of product design and manufacturing software, with subsidiaries in North America, Europe and Asia. Edgecam: EdgeCAM is a computer aided manufacturing (CAM) program developed by Planit. EdgeCAM specialises in solid based machining. It has support for direct translation of Solidworks solid files, as well as files from other popular CAD systems, like Inventor, Solid Edge, Pro/ENGINEER, Pro/DESKTOP, UGS NX and CATIA.

EdgeCAM is a complete CAM software solution for production machining and mold & die applications. It has an extensive range of 2-5 Axis milling, turning and mill/turn strategies, seamless CAD integration and sophisticated automation tools. EdgeCAM applications include prismatic and surface milling, complex multi-axis turning, mill/turn, rotary and multi-plane milling and family of parts machining. Supporting solutions for a more productive and profitable machine shop are supplied. These include toolpath simulation, a wizard approach to post processing, a comprehensive tooling database, intuitive and flexible machine tool communications and a web-enabled job management system. EdgeCAM provides the production machine shop with a wide range of flexible milling cycles. Machining efficiency is maximized on simple and complex prismatic parts as well as those incorporating sculptured surface geometry. EdgeCAM provides prismatic machining combined with powerful 3D solid and surface machining strategies. EdgeCAM Turning provides functionality for a wide range of machine tools, including 2-axis lathes, multi-turret configurations, sub-spindle turning centers and mill/turn machines. On a mill/turn machine, C-, Y- and B-axis milling and drilling take place within the same program as the turning to provide a fully integrated and associative programming solution. Ease of use and an understanding that cycle times are critical, especially on multi-configuration mill/turn machines, underpin the development of EdgeCAM's turning functionality. EdgeCAM produces advanced rough and finish turning cycles, together with support for facing, boring and drilling in either canned cycle or longhand format. Toolpath calculation takes into consideration the complete tooling insert and previously machined material to avoid gouging and eliminate air cutting. EdgeCAM offers support for Sandvik Coromant Wiper inserts for turning tools, allowing these productivity enhancing inserts to be used reliably in all aspects of production machining. Promanufacuring: CAM, if treated secondarily to CAD, can yield opportunities for costly delays and production mistakes. Pro/ENGINEER Production Machining provides manufacturing engineers with robust NC programming capabilities for directly cutting and shaping product parts using milling, turning, and wire EDM. And, since it enjoys seamless compatibility with the design, changes are automatically incorporated. The result: improved time to production and customer responsiveness. Improve your manufacturing tooling and factory equipment design processes with Pro/ENGINEER Production Machining. Benefits • •

Includes all the capabilities of prismatic and multi-surface milling Supports CNC mills, 2-axis/4-axis CNC lathes, and 2-axis/4-axis CNC wire EDM machines

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Provides low-level NC sequence editing, allowing precise toolpath control and optimization Detailed step-by-step production planning instructions improves manufacturing efficiency, and reduces development cost Optimized NC programming for families of designs accelerates time-tovolume production.

G Codes: G-code is a common name for the programming language that controls NC and CNC machine tools. Developed by the Electronic Industries Alliance in the early 1960s, a final revision was approved in February 1980 as RS274D. Due to the lack of further development, the immense variety of machine tool configurations, and little demand for interoperability, few machine tool controllers (CNCs) adhere to this standard. Extensions and variations have been added independently by manufacturers, and operators of a specific controller must be aware of differences of each manufacturers' product. When initially introduced, CAM systems were limited in the configurations of tools supported. Manufacturers attempted to overcome compatibility difficulties by standardizing on a machine tool controller built by Fanuc. Unfortunately, Fanuc does not remain consistent with RS-274 or its own previous standard, and has been slow at adding new features and exploiting the increase in computing power. For example, they changed G70/G71 to G20/G21; they used parentheses for comments which caused difficulty when they introduced mathematical calculations so the use square parentheses for macro calculations; they now have nano technology recently in 32-bit mode but in the Fanuc 15MB control they introduced HPCC (high-precision contour control) which uses a 64-bit RISC (reduced instruction set computer) processor and this now has a 500 block buffer for look-ahead for correct shape contouring and surfacing of small block programs and 5-axis continuous machining. This is also used for NURBS to be able to work closely with industrial designers and the systems that are used to design flowing surfaces. The NURBS has its origins from the ship building industry and is described by using a knot and a weight as for bending steamed wooden planks and beams.

Computer-aided engineering: Computer-aided engineering ((often referred to as CAE)) is the use of information technology for supporting engineers in tasks such as analysis, simulation, design, manufacture, planning, diagnosis and repair. Software tools that have been developed for providing support to these activities are considered CAE tools. CAE tools are being used, for example, to analyze the robustness and performance of components and assemblies. It encompasses simulation, validation and optimization of products and manufacturing tools. In the future, CAE systems will be major providers of information to help support design teams in decision making.

In regard to information networks, CAE systems are individually considered a single node on a total information network and each node may interact with other nodes on the network. CAE systems can provide support to businesses. This is achieved by the use of reference architectures and their ability to place information views on the business process. Reference architecture is the basis from which information model, especially product and manufacturing models. The term CAE has also been used by some in the past to describe the use of computer technology within engineering in a broader sense than just engineering analysis. It was in this context that the term was coined by Dr. Jason Lemon, founder of SDRC in the late 70's. This definition is however better known today by the terms CAx and PLM. CAE areas covered include: • • • • • •

Stress analysis on components and assemblies using FEA (Finite Element Analysis); Thermal and fluid flow analysis Computational fluid dynamics (CFD); Kinematics; Mechanical event simulation (MES). Analysis tools for process simulation for operations such as casting, molding, and die press forming. Optimization of the product or process.

In general, there are three phases in any computer-aided engineering task: •

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Pre-processing – defining the model and environmental factors to be applied to it. (typically a finite element model, but facet, voxel and thin sheet methods are also used) Analysis solver (usually performed on high powered computers) Post-processing of results (using visualization tools)

This cycle is iterated, often many times, either manually or with the use of commercial optimization software.

Softwares of CAE: ANSYS: ANSYS, Inc. is one of the world’s leading engineering simulation software providers. It develops general-purpose finite element analysis and computational fluid dynamics software. ANSYS develops a complete range of computer-aided engineering (CAE) products, but it is perhaps best known for its ANSYS Mechanical and ANSYS Multiphysics products. ANSYS Mechanical and ANSYS Multiphysics software are self-contained analysis tools incorporating pre-processing (geometry creation, meshing), solver and postprocessing modules in a unified graphical user interface. These are general-purpose

finite element modeling packages for numerically solving a wide variety of mechanical problems, including static/dynamic structural analysis (both linear and non-linear), heat transfer and fluid problems, as well as acoustic and electro-magnetic problems. The software is used to analyze a broad range of applications. ANSYS Mechanical technology incorporates both structural and material non-linearities. ANSYS Multiphysics software includes solvers for thermal, structural, CFD, electromagnetics, and acoustics and can couple these separate physics together in order to address multidisciplinary applications. ANSYS software is also used in Civil Engineering(ANSYS/CivilFEM), Electrical Engineering, Physics and Chemistry. ANSYS acquired the CFX computational fluid dynamics code in 2003 and Fluent, Inc. in 2006. The CFD packages from ANSYS are powerful and flexible, used for engineering simulations of all levels of complexity. They offer a comprehensive range of physical models that can be applied to a broad range of industries and applications. MSC.Adams/Control: Highlights: ⇒ ⇒ ⇒ ⇒ ⇒

Build complex mechanical system models without writing equations Visualize simulation results with animation and strip-charts Model full nonlinear effects including flexibility and collisions Modify parametrically defined geometry and physical properties Integrate seamlessly with Simulink models

Description: MSC.Adams/Control help control system developers eliminate the need to write complex equations of motion for mechanical plants. The software enables users to graphically model mechanical systems, containing a variety of constraints and force types as well as parts of arbitrary shape, then directly integrate their Simulink developed control system models within these mechanical system designs. Users can then simulate their systems' full-motion behavior from within the Simulink environment and visualize the results using animations and plotting. The ADAMS suite of tools allows virtual prototyping and virtual testing -- the ability to build and test your complex products in the computer before committing to expensive and time-consuming physical prototyping and testing. Employing an interactive graphical environment and libraries of components, joints, and forces, ADAMS enables engineers to parametrically model 3-D mechanical systems and study alternative designs as "virtual prototypes" by simulating and comparing realistic motion behavior.

Abaqus: Abaqus is a commercial software package for finite element analysis developed by SIMULIA, a brand of Dassault Systemes S.A. The Abaqus product suite consists of three core products: Abaqus/Standard, Abaqus/Explicit and Abaqus/CAE. Abaqus/Standard is a general-purpose solver using a traditional implicit integration scheme to solve finite element analyses. Abaqus/Explicit uses explicit integration scheme to solve highly nonlinear transient dynamic and quasi-static analyses. Abaqus/CAE provides an integrated modeling (preprocessing) and visualization (postprocessing) environment for the analysis products. The Abaqus products use the open-source scripting language Python for scripting and customization. Abaqus/CAE uses the fox-toolkit for GUI development. Abaqus is used in the automotive, aerospace, and industrial product industries. The product is popular with academic and research institutions due to the wide material modeling capability, and the program's ability to be customized. Abaqus also provides a good collection of multiphysics capabilities, such as coupled acoustic-structural, piezoelectric, and structural-pore capabilities, making it attractive for production-level simulations where multiple fields need to be coupled. Abaqus was initially designed to address non-linear physical behavior; as a result, the package has an extensive range of material models. Its elastomeric (rubberlike) material capabilities are particularly noteworthy. The spelling for ABAQUS derives from the Greek word, aba-kala-culus, meaning the memory solver. Abaqus was originally spelled in capital letters; however after a rebranding of the company and the introduction of the SIMULIA brand, Abaqus is now in lower case letters, with an upper case 'A'.

Computer-aided design: Computer-Aided Design (CAD) is the use of computer technology to aid in the design of a product. Current software packages range from 2D vector base drafting systems to 3D solid and surface modellers. Origins and terminology: CAD originally meant Computer-Aided Drafting or designing because of its original use as a replacement for traditional drafting. Now, CAD usually means Computer Aided Design to reflect the fact that modern CAD tools do more than just drafting. CAD is sometimes translated as "computer-assisted", "computer-aided drafting", or a similar phrase. Related acronyms are CADD, which stands for "computer-aided design and drafting", CAID for computer-aided industrial design and CAAD, for "computer-aided architectural design". All of these terms are essentially synonymous, but there are a few subtle differences in meaning and application.

Introduction:

The CAD process.

Commercial floor plan. CAD is used to design, develop and optimize products, which can be goods used by end consumers or intermediate goods used in other products. CAD is also extensively used in the design of tools and machinery used in the manufacture of components, and in the drafting and design of all types of buildings, from small residential types (houses) to the largest commercial and industrial structures (hospitals and factories). CAD is mainly used for detailed engineering of 3D models and/or 2D drawings of physical components, but it is also used throughout the engineering process from conceptual design and layout of products, through strength and dynamic analysis of assemblies to definition of manufacturing methods of components. CAD has become an especially important technology, within the scope of Computer Aided technologies, with benefits such as lower product development costs and a greatly shortened design cycle. CAD enables designers to lay out and develop work on screen, print it out and save it for future editing, saving time on their drawings.

Softwares of CAD: AutoCAD: AutoCAD is a CAD software application for 2D and 3D design and drafting, developed and sold by Autodesk, Inc. Initially released in late 1982, AutoCAD was one of the first CAD programs to run on personal computers, and notably the IBM PC. Most CAD software at the time ran on graphics terminals connected to mainframe computers or mini-computers. In earlier releases, AutoCAD used primitive entities — such as lines, polylines, circles, arcs, and text — as the foundation for more complex objects. Since the mid1990s, AutoCAD has supported custom objects through its C++ API. Modern

AutoCAD includes a full set of basic solid modeling and 3D tools, but lacks some of the more advanced capabilities of solid modeling applications. AutoCAD supports a number of application programming interfaces (APIs) for customization and automation. These include AutoLISP, Visual LISP, VBA, .NET and ObjectARX. ObjectARX is a C++ class library, which was also the base for products extending AutoCAD functionality to specific fields, to create products such as AutoCAD Architecture, AutoCAD Electrical, AutoCAD Civil 3D, or third-party AutoCAD-based applications. AutoCAD's native file format, DWG, and to a lesser extent, its interchange file format, DXF, have become de facto standards for CAD data interoperability. AutoCAD in recent years has included support for DWF, a format developed and promoted by Autodesk for publishing CAD data. In 2006, Autodesk estimated the number of active DWG files to be in excess of one billion. In the past, Autodesk has estimated the total number of DWG files in existence to be more than three billion. AutoCAD currently runs exclusively on Microsoft desktop operating systems. Versions for Unix and Macintosh were released in the 1980s and 1990s, but these were later dropped. AutoCAD can run on an emulator or compatibility layer like Virtual PC or Wine, keeping in mind the performance issues that can arise when working with 3D objects or large drawings. AutoCAD and AutoCAD LT are available for German, French, Italian, Spanish, Japanese, Korean, Chinese Simplified (No LT), Chinese Traditional, Russian, Czech, Polish, Hungarian (No LT), Brazilian Portuguese (No LT), Danish, Dutch, Swedish, Finnish, Norwegian and Vietnamese. The extent of localization varies from full translation of the product to documentation only. IGES: The Initial Graphics Exchange Specification (IGES) (pronounced eye-jess) defines a neutral data format that allows the digital exchange of information among Computeraided design (CAD) systems. The official title of IGES is Digital Representation for Communication of Product Definition Data, first published in January, 1980 by the National Bureau of Standards as NBSIR 80-1978. Many documents (like MIL-D-28000) refer to it as ASME Y14.26M, the designation of the ANSI committee that approved IGES Version 1.0. Using IGES, a CAD user can exchange product data models in the form of circuit diagrams, wireframe, freeform surface or solid modeling representations. Applications supported by IGES include traditional engineering drawings, models for analysis, and other manufacturing functions. Pro/ENGINEER: Pro/ENGINEER (commonly referred to as Pro/E or ProE) is a 3D CAD parametric feature solid modeling software created by Parametric Technology Corporation (PTC). Its direct competitors are UGS-NX and CATIA, and to a lesser degree

SolidWorks, Autodesk Inventor and SolidEdge. It runs on several UNIX flavours, Linux and Microsoft Windows, and provides solid modeling, assembly modelling and drafting functionality for mechanical engineers. Pro/ENGINEER is an integrated 3D CAD/CAM/CAE solution for mechanical engineering and design which was created by Dr. Samuel P. Geisberg in the mid1980's. It pioneered the CAD industry by introducing the concept of Parametric, Feature-based Solid Modeling. Models are driven parameters and intelligent features, rather than simple dimensional values. Pro/ENGINEER outputs consist of solid model data for tooling and rapid prototyping, CNC manufacturing, and finite element analysis. A product and its entire Bill of Materials can be modeled accurately with fully associative engineering drawings, and revision control information. It is compatible with Windows and Unix-variants. All data is interchangeable between these platforms without conversion. PTC also provides a comprehensive product development system that helps companies optimize their product development processes. This integral, interoperable and internet-based system provides the capabilities to create, colllaborate, control, configure, and communicate product development information. PTC's product families include Pro/ENGINEER, CoCreate, Windchill, ProductView Mathcad, and Arbortext. SolidWorks: SolidWorks is a 3D mechanical CAD (computer-aided design) program that runs on Microsoft Windows and was developed by SolidWorks Corporation - now a subsidiary of Dassault Systèmes, S. A. (Suresnes, France). SolidWorks is a parametric feature-based solid modeler, using the Parasolid geometric modeling kernel. SolidWorks was introduced in 1995 as a low-cost competitor to CAD programs such as Pro/ENGINEER, SDRC I-DEAS, Unigraphics and CATIA, and is currently one of the most popular products in the "midrange" or "mainstream" mechanical CAD market. SolidWorks employs a parametric, feature-based approach to creating models and assemblies. Parameters refer to constraints or conditions whose values determine the size, shape, characteristics, and behavior of the model or assembly. Parameters can be either numeric, for example dimension values such as the diameter of a circle or the length of a line; or geometric, such as conditions like tangent, concentric, coincident, parallel, horizontal, and the like. Numeric parameters such as dimensions can easily be related to each other through equations to capture even the most complicated design intent. Features refer to the building blocks of the part. They are the shapes and operations that construct the part. Shape-based features would include slots, holes, bosses and the like that either add or remove material from the part. Shape-based features typically begin with either a 2D or 3D sketch. Operation-based features generally don’t have sketches. These types of features include operations like filleting, chamfering, shelling, or applying draft to a part.

screen shot captured from a SolidWorks top down design approach. Building a model in SolidWorks usually starts with either a 2D or 3D sketch. The sketch consists of geometry such as lines, arcs, conics, and splines. Dimensions are added to the sketch to define the size and location of the geometry. Relations are used to define attributes such as tangency, parallelism, perpendicularity, concentricity, and such. The parametric nature of SolidWorks means the dimensions and relations drive the geometry, not the other way around. The dimensions in the sketch can be controlled independently, or by relationships to other parameters outside the sketch. For example, you can sketch a rectangle and dimension its height and width. Then you can extrude the rectangle to create a rectangular prism. You can then relate the length of the extrusion to the height of the rectangle so that if extrusion gets longer, the height changes accordingly. Furthermore, you can subsequently add a hole in the face of the prism and create another relationship so that the diameter of the hole, which was created after the prism, drives the width of the prism. This way, if the hole has to grow larger, the prism’s dimensions would also increase to accommodate it. Another aspect of the feature-based nature of SolidWorks is you can roll back into the history of the part in order to make changes, add additional features, or change to sequence in which operations are performed. In an assembly, the analog to sketch relations are mates. Just as sketch relations define conditions such as tangency, parallelism, and concentricity with respect to sketch geometry, assembly mates define the same relations with respect to the individual parts or components. This means you can assemble parts with the same easily edited intelligence that you have in part modeling. Beyond the simple mates are advanced mates that include gear and cam and follower mates. MicroStation: MicroStation is an innovative CAD platform used by teams of architects, engineers, contractors, and GIS professionals to integrate work on buildings, civil engineering projects, power plants, and geospatial information. MicroStation is used by a majority of the global design elite for very good reason. Here's why: • • • •

MicroStation provides a sound platform for BIM. At the heart of Bentley's DigitalPlant strategy is MicroStation Forty-seven out of 50 U.S. State DOTs standardize on MicroStation. The whole world is mapped using MicroStation and DGN

CATIA: CATIA (Computer Aided Three dimensional Interactive Application) is a multiplatform CAD/CAM/CAE commercial software suite developed by French company Dassault Systemes and marketed world-wide by IBM. The software was originally intended for the development of Dassault's Mirage fighter jet, but became a runaway success and was subsequently adopted by numerous well known companies worldwide, such as Boeing and IBM. The software was also famously used by architect Frank Gehry in his building of the Guggenheim Museum Bilbao. CATIA is written in the C++ programming language. CATIA is the corner stone of the Dassault Systemes PLM software suite. Commonly referred to as a 3D Product Lifecycle Management software suite, CATIA supports multiple stages of product development (CAx). The stages range from conceptualization, through design (CAD) and manufacturing (CAM), until analysis (CAE). CATIA provides an open development architecture through the use of interfaces, which can be used to customize or develop applications. The supporting application programming interfaces are as follows: • •

The Fortran and C programming languages for version 4 (V4). The Visual Basic and C++ programming languages for version 5 (V5).

These APIs are referred to as CAA for V4 and CAA2 (or CAA V5) for V5. The CAA2 are component object model (COM) like interfaces. They provide integration for products developed on the CATIA suite of software. Although later versions of CATIA V4 implemented NURBS, version 4 principally used piecewise polynomial surfaces. CATIA V4 uses a non-manifold solid engine. Catia V5 features a parametric solid/surface-based package which uses NURBS as the core surface representation and has several workbenches that provide KBE support. As of 2007, the latest release is V5 release 18 (V5R18). One of the main reasons customers choose CATIA V5 is its ability to seamlessly interact and work in tandem with a host of other applications like Enovia, Smarteam, various CAE Analysis applications etc.