Virtual Theory Of Machine Lab

Virtual Theory of Machine Lab

ABSTRACT As the title suggest, the project work will be carried out on software. The project work involves three major software 1) pro/e (2001 or 2003 wildfire) 2) 3dmax studio 3) VRML. Pro/e will be used for modeling purpose, as pro/e is a parametric modeling package, therefore modification in design as well as dimensions can be modified very easily. It the most popular software used among engineers and designers. This project enables us to acquire and master skills of pro/e that will be useful to us in our professional carrier in our future. We have planned to include basic mechanism of theory of machine subject. These mechanisms are complex to understand and explain theoretically. This project work aims at simulation of the mechanism, which will be quite easy to understand. We are undertaking this project work for students of second 4th semester production engineering.

Concept behind the project: - The project aims at creating a 3d educational multimedia for teaching learning process. The traditional multimedia in engineering involves 2d graphics whereas this project aims at 3d graphics, which will be more realistic to real mechanisms. VRML (virtual reality modeling language) is a plug in used on Internet explorer to view the 3d models in their working condition. VRML also enables to display the project on Internet so that anybody can access these models where the Internet is available. This eliminates need of carrying CD ROM.

Beneficial from the project : We are developing this project for teachers/instructors / lab assistance as well as students.

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Supporting literature to be studied: Following are the references, which will be most useful for our project 1) LEARN VRML IN 21 DAYS BY: CHRIS MARRIN AND BRUCE CAMPBELL 2) THEORY OF MACHINE BY R.S. KHURMI 3) PRO/E WILDFIRE BY SHYAM TICKOO

Methodology experiment to be adapted: the project work can be distinguished by three phases. 1) Modeling 2) simulation 3) viewing and interaction Simulation is the most critical part of our project, which will be carried out in 3d-max studio software. This software is used for animation purpose worldwide. The last phase that viewing and interaction will be carried out in VRML. Result expected: we will publish all the models on web in a form of small site on any free web-hosting server. This site will contain selected the working models of theory of machine with VRML software to down load. The web site will also explain in brief the concept of project and profile of members of project. With the LCD projector facility this project can be very well explained to group of students during expert lectures or in classroom teaching. We will develop the output in CD form, which can be distributed to the students.

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ABOUT VRML 3D graphics are all the rage today. We see them everywhere: in video games, advertising, even feature-length films. We have come to a point in history where we can create completely synthetic worlds that exist entirely inside a computer's memory. These worlds have been referred to in the popular media as "virtual reality," "cyberspace," or "the metaverse." These terms are great for a science fiction writer in search of a new book idea, but we are many years away from virtual worlds that are anywhere near the rich detail of the real world. However, 3D graphics give us much more than the future promise of virtual reality. They give us a powerful new tool for the presentation of information, art, and entertainment. And while I don't think virtual reality will ever overtake the real world, as so many science fiction movies would like us to believe, they will add to our repertoire of creative outlets. The World Wide Web adds an interesting new twist to the use of 3D graphics. In the past, the presentation of art or information was limited to those who could get their work shown in an art gallery, or to someone with access to a publishing house or television studio. But, access to the Web is relatively inexpensive, so almost anyone can communicate their ideas, as long as they know how to use the tools that turn their dreams into reality. VRML is the tool for creating 3D virtual experiences on the World Wide Web. Even though it is in its infancy, VRML will allow you to realize your visions and make them available to everyone on the Web.

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The purpose of this book is to help you get started using VRML. VRML is all about dynamic, moving experiences, so in the next seven chapters I will show you how to add life to your worlds and how to give visitors the ability to interact with them. In the last seven chapters, I will describe the most advanced features of VRML and show you how to create full multimedia experiences, integrating 2D and 3D elements. VRML is an exciting new development. It has been a lifelong dream of mine to be involved in something with the potential to change the world in a very positive and fundamental way. VRML is the realization of that dream for me.

VRML Background The notion of 3D graphics has been very popular lately, from video games to weather simulations to movies that give us a glimpse of virtual reality, complete with virtual villains and cyberheroes. The World Wide Web has gained even more popularity. Therefore, it is natural that people would want to join the two, marrying the compelling experience of 3D to the global access of the Web. VRML was born to solve just this problem: how to put compelling 3D onto every PC connected to the WebD you'll explore the phenomenon of the World Wide Web and how VRML was created to put interconnected 3D worlds onto every desktop. # Why use 3D on the Web? # A short history of VRML. # Authoring VRML worlds. # Tools and resources

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The World Wide Web has grown from a curiosity on college campuses to a major force in business in fewer than five years. It seems as though there is not a TV commercial, billboard, or panel truck without the now familiar http://.... The Web is the subject of jokes, talk shows, and articles in major magazines. You can buy wine and movie tickets on the Web, see the latest shots from the space shuttle, and find out the weather in any corner of the world, as long as you know the magic incantation, http://www.weather.com/current/. As with many of the inventions now taken for granted, no one knew what the Web would become when it was first conceived. It started out as an easier way to browse text pages on large computer databases. It was soon realized that some sort of text formatting and the capability to add images to a page were crucihal to the successful presentation of the information. Thus, the HyperText Markup Language (HTML) was born. An outgrowth of publishing standards of the late 1980s, HTML is a simple text-based file format with embedded commands (known as tags) to instruct the computer how to display the information. For instance, surrounding a word with the tags and causes that word to be displayed in bold. There are tags to distinguish between a heading and body text, to center text, and to create bulleted lists, to name a few. HTML also has a tag to embed images on a page, and it is here that HTML started down die path toward full multimedia integration. Brochures, magazines, and other printed material consist basically of words and images, with the occasional background color to set off a VRML Background sidebar. With text formatting and embedded images, HTML can handle most of this. But this is all static information, and because it is being

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displayed on a computer screen, it is ideally suited to dynamic presentations with motion, sound, and interactivity. This interactivity is easy to find at information kiosks in malls and airports where maps of the area and restaurant choices have been available for years. But these are all custom installations, created for a specific purpose. The next goal of the Web became bringing that richness of information presentation to every desktop,

A Short History of VRML The origins of VRML date back to the middle of 1994, to a European Web conference in which Tim Berners-Lee talked about the need for a 3D Web standard. He coined the name VRML (Virtual Reality Markup Language) as an acronym to parallel HTML. Mark Pesce picked up on this idea and was able to persuade Brian Behlendorf at Wired magazine to start a mailing list called www-vrml. The VRML mailing list was the seed from which a thriving community of artists, engineers, and visionaries grew. The name was quickly changed to Virtual Reality Modeling Language to reflect the emphasis on worlds rather than pages of text. This group produced the VRML 1 specification in record time purely through e-mail interactions. This was possible thanks in part to the fact that it was based on the Inventor file format from Silicon Graphics. Inventor is a mature file format used everywhere from universities doing research to animation houses doing special effects for movies and television. A subset of Inventor was chosen that facilitated implementation on a wide variety of platforms. Although this allowed several VRML browsers to be created, it also

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crippled the language to a certain extent Inventor's advanced interaction and animation capabilities were not included, so VRML 1 worlds were as still as a graveyard. So, before the ink even had a chance to dry on the specification, work was started to bring life to those Virtual worlds. A small extension to VRML, called VRML 1.1, was tried. It contained facilities to add audio clips to a scene and some very primitive animation. But because this was not nearly enough to create compelling content, VRML1.1 never saw the light of day. The VRML community set its sights on a major overhaul of the language and dubbed it VRML 2.

The Requirements Gavin Bell was the SGI engineer primarily responsible foj- introducing the VRML community to Inventor. In thinking about 2, he conceived of three requirements he deemed important for 3D Web content: composability, scalability, and extensibility. Composability allows an author to create a virtual house, scale it down, and place it on a tabletop. This table with the house model can then be placed in the office building of a virtual architecture company. This building can be placed on a city block with other buildings, which, in turn, can be placed in a city, which can be placed on a planet orbiting the sun. In this composition, each piece is independent of the rest. The full-size house can be placed on a residential street somewhere else on the planet because everything that makes it a house, from the attic light that can be switched on to the door that opens to the basement, is contained within the house model.

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Scalability allows worlds of arbitrary size to be created. With VRML, it must be possible to see a galaxy, zoom in on a star system, then to a planet, then a city, a block, a park, a man sitting on a bench, and the mosquito sitting on his arm. This is difficult due to limits in the precision of computer hardware, but it is important to prevent every world from having arbitrary limits in size or detail. Extensibility allows an author to extend the capability of the language to serve special purposes. This allows, for instance, multiuser worlds to be created or new geometric objects to be added to VRML.

Tools and Resources for VRML How do you get started in writing VRML 2 worlds? First, you need a way to display your work. CosmoPlayer from Silicon Graphics is included on the CD-ROM that comes with this book. After installing it, you can view some of the VRML 2 worlds included on the CD-ROM. Installing CosmoPlayer CosmoPlayer runs under Windows 95 and works with Netscape Navigator 2 or 3.0 or Internet Explorer 3.0. To install it, follow these steps: 1. Insert the CD-ROM into the drive. 2. Double-click My Computer. 3. Double-click on the CD-ROM icon. 4. Double-click on the icon labeled npcosmop.exe. 5. When the installation begins, follow the on-screen instructions. I

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Basic VRML Concepts Now that you understand how VRML relates to the Web, let me show you how to create worlds of your own. You will be creating VRML yourself, so have Microsoft WordPad or your favorite text editor ready. Give any VRML file you create a suffix of .wrl. Then, as long as you have Netscape Navigator(or Internet Explorer) and CosmoPlayer set up properly, you can just click your files and display your 3D creations. 2D versus 3D graphics.

2D Versus 3D Graphics There is a big difference between 2D and 3D. Although this makes it harder to work with 3D, it also gives 3D huge advantages over 2D. You can create a 3D world, populate it with interesting objects, and then walk around that world using a 3D browser such as CosmoPlayer. The only way to get similar motion using 2D is by using movies, such as MPEG, or image-based formats, such as Shockwave from Macromedia. Both of these techniques create huge files that are extremely slow to download over the Web, and are not as flexible. The only viewing angle you have is the one the author has created for you. With 3D and VRML, you can go literally anywhere in the 3D world. You can walk up to a sign to read it, look over your shoulder to see where a sound is coming from, or walk up a flight of stairs to go into a second-story office. The compactness of 3D comes from the ability of the author to define objects as skeletons, to be filled in by the computer rendering the image. For a 2D image, you must define the color of every pixel on the screen. For 3D, you download the skeletal objects,

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pick a vantage point from which to view them, and then let the renderer do the rest. In VRML, the renderer can paint objects with 2D images. However, because they are repeated, they can be small and reused on many objects. For example, an image of inlaid stones could be used to represent a stone wall or a stone walkway. These images are called textures. As a VRML author, your job is to come up with an idea (often the hardest task of any job), create the skeletal models to realize your idea, and then combine these models into a VRML file. Once this is finished, you have created a virtual world.

The Future of VRML This is an exciting time for VRML. Now new browsers are available, and the current browsers will be more feature-rich and stable. But with the excitement also comes frustration. Making compelling content is difficult when products are changing so fast. But those who are now creating content will have some beautiful results a year from now, according to my VRML crystal ball. One Year Out The most important change we will see in the next year will be the wide availability of good-quality stable and compatible VRML browsers. With that will naturally come the first batch of really exciting and rich virtual environments. There will be game worlds, virtual shopping malls, and online museums. Some of these will be created purely for pleasure; others will be proving that 3D on the Web can be a compelling tool for business. When VRML catches the eye of the business community, its growth, which is very rapid right now, will become extraordinary. The commercialization C.O.E & T, Ak ola.

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of this technology troubles some, mostly from an artistic point of view. But while business will use 3D to sell, it will also stimulate the availability of tools for content creation and better hardware for browsing. This brings me to my next prediction: better tools. Some good tools for VRML authoring are available today. But many more are needed. we believe that over the next year you will see 3D Web tools to fit every niche, suitable for everyone from the professional graphics artist to the casual user. Forces are at work outside the VRML community that are giving users a wider choice of platforms for both browsing and creating Web content. Because of this, we believe that the new VRML tools will be available on many kinds of platforms, using many new technologies such as Java and HTML, to supply novel and flexible solutions to the problem of creating content for the new rich medium of VRML. Finally, It’s quite sure many interesting and sometimes bizarre applications for VRML will be seen. You can already see historic sites, where you can view the reconstruction of an ancient city, and sites showing what a decaying neighborhood will look like after a proposed renovation. Of course, not all sites will have such high ideals. Games will no doubt dominate VRML in the short term. A few holiday sites are popping up, with fun experiences for Halloween, Christmas, or New Year's. Then there's the site where you can create your own coffin, with a full 3D visualization. I'm sure the technology will show much progress over the next year. But what about the next milestone? What will happen in the next five years?

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Five Years Down the Virtual Road The way begins to get a bit murky this far down the path into the future. But assuming that the Web grows at the expected rate, VRML should be quite embedded in our everyday lives. WE mean that quite literally. Many manufacturers are talking about placing computer hardware into television sets. Just plug the TV into the cable connection and you have access to the world. It's hard to imagine the Internet surviving such a crush of new subscribers. When 75 percent of the homes in the world are online, the traffic of people talking, browsing, and exploring at all hours of the day or night will be unimaginable. But these big problems will be solved as they always have been. Necessity is the mother of invention, so someone will come up with solutions just in time to avert a major world crisis! This connectivity will be wonderful for VRML. With good 3D graphics hardware available; free inside your TV set, everyone will be able to have rich virtual experiences that, we can only dream of today. Five years is not quite enough time to make this experience available to everyone, but the effort will have made great progress by then. Multiuser virtual environments will be common, complete with lifelike, animated avatars and the ability to walk up to someone, hand him a briefcase full of information, and chat with him about the weather. Anyone with a few cyberbucks will be able to buy a little homestead on this virtual landscape, and set up shop, or just create a fortress of solitude, free from the noise and influences of the virtual city. Business on the Web will be in full swing by then. You'll be able to have all your cash online, so you'll be able to swing into the cybermall, try some new pants on your avatar, and buy the pants with your cyberbucks. Back in the real world, your pants will C.O.E & T, Ak ola.

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still take a couple of days to get to you, but you won't care because you'll be too busy trying to be a corporate tycoon in a new, multiplayer business game. But VRML and the Web won't be all high-tech fun and games. You'll be able to cruise around a model of that new lodge in the National Park you've been wanting to visit. That way, you can check out the view from various rooms before making a reservation and travel plans to get away from the TV and spend some quality time relaxing in the real world. Just like many technologies before it, such as the telephone and the airplane, VRML, and the Web in general, will eventually blend into society and become an ordinary tool. But it will be an amazingly powerful tool that will entertain you when you want entertainment and help you when you need help.

The Distant Future Looking out beyond five years is largely pointless. With developments happening as fast as they are, something that we can't now imagine will surely come on the scene and will completely change the landscape (both real and virtual). The only thing you can say with certainty is that VRML is changing rapidly and, by all indications, will continue to do so well into the future.

Questions & Answers Q How can I keep up with all the changes taking place with VRML and other virtual reality technologies? No one can keep up completely nowadays. we recommend surfing the Internet to see what all the top companies are up to. Open up your favorite search engine in your Web C.O.E & T, Ak ola.

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browser and search on VRML and Virtual Reality. Also, read the online magazines devoted to VRML. If you can, download the latest beta copies of each browser and take a tour with them. Keep a list of the features of each browser. Spend some time thinking about the algorithms required to make a browser work. Keep a link to the VRML Consortium home page and other VRML-related organizations. And, by all means, go to the conferences where all the best ideas are presented and discussed. You'll never run out of things to think about, because VRML is involved in so many different disciplines, including education, scientific visualization, communication, psychology, physiology, anthropology, and entertainment, to name a few.

Q Why would I want to use 3D on the Web? Why would I need anything more than the text and images that are already on an HTML page? A The use of 3D on the Web has many great benefits. First, it allows a virtually infinite amount of interactivity. Viewing an image of the outside of a house is not nearly as interesting or informative as being able to walk through the front door and up to the master bedroom to check out the view. Second, 3D is much more compact than either images or text. They say that a picture is worth a thousand words. If that's true, a 3D world is worth a thousand pictures. Finally, 3D gives an author a richer medium in which to express ideas.

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Q Why was VRML created from scratch, rather than from one of the existing 3D formats? A VRML does build on the Open Inventor file format from Silicon Graphics. Inventor was intended to be a portable, cross-platform file format. Many other formats available were either proprietary or insufficient to meet the requirements of VRML. This was true because 3D had always been such a niche market that there was not enough of a need for a standard file format. The Web changed all that, so VRML was created.

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ABOUT 3D MAX 3ds max claims that "You bring the imagination. We'll bring the rest". New Features 3ds max® software offers powerful new features designed to increase performance and boost productivity Industry-leading normal mapping tools: 3ds max animation technology includes all new tools for creating normal maps and previewing the results in the viewport using DX9 shaders. Plus, 3ds max is now the first major 3D application to support normal maps in the rendering process, allowing artists to add amazing detail while limiting the total volume of geometry in a scene. Performance: Stability and performance are critical issues to any 3D artist. 3ds max technology continues to enhance stability while introducing numerous performance enhancements, including the new TurboSmooth smoothing system, increased Viewport speed, and a new Object Culling system that procedurally reduces the number of objects displayed, keeping the focus on critical aspects of the scene. What we learn by using 3ds max studio and by completing 3ds max course during this project? The 3ds max course incorporates the features, commands and techniques for creating and animating 3D models and rendering scenes with hands-on exercises. The course covers techniques for implementing various modeling methods, applying materials, placing lights and cameras, and creating still and/or animated images.

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Course Benefit: Upon completion of the course, we become familiar with the 3ds max Interface.  Understand the fundamental concepts and features of 3ds max.  Create and edit models  Define and apply materials •  Place lights and/or cameras  Create simple animations  Render the still or animated scene Course Pre-requisites: No previous 3ds max experience necessary. However, basic knowledge of computers and Windows operating system is needed. Course Contents trough which the projectee gone: Module 01 – Introduction to 3ds max  3ds max interface  Opening and saving scenes  Creating versions of a project Module 02 – Introduction modeling • Creating primitive objects • Selecting models • Removing models from a scene • Creating extended primitive objects • Changing models parameters C.O.E & T, Ak ola.

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• Basic rendering techniques

Module 03 – Modifying Models • Transforming techniques • Cloning techniques • Modifiers

Module 04 – Creating 3D Models with 2D Shapes • Creating 2D splines and shapes • Modifying splines and shapes • Extruding and Lathing • Rendering shades

Module 05 – Materials • Material Editor • Defining and applying materials Module 06 – Animation • Lights • Cameras • Basic animation techniques • Modifying Keys Why this course?

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3ds max is the world’s most widely used professional 3D modeling, animation and rendering software. It significantly improves connectivity, image quality, productivity, and content delivery. It provides ability to create heightened realism through global illumination, exposure, accurate physical controls and custom hardware support. This course helps to conceptualize and communicate various color schemes and is highly user friendly to frequent changes and add-ons. Audience: This course is intended for Designers, Drafters, Architects and professionals involved with graphics and design. People in related roles can also benefit from taking this course.

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ABOUT Pro/ENGINEER Pro/ENGINEER provides mechanical engineers with an approach to mechanical design automation based on solid modeling technology and the following features. 3-D MODELING

The essential difference between Pro/ENGINEER and traditional CAD systems is that models created in Pro/ENGINEER exist as three-dimensional solids. Other 3-D modelers represent only the surface boundaries of the model. Pro/ENGINEER models the complete solid. This not only facilitates the creation of realistic geometry, but also allows for accurate model calculations, such as those for mass properties. PARAMETRIC DESIGN

Dimensions such as angle, distance, and diameter control Pro/ENGINEER model geometry. You can create relationships that allow parameters to be automatically calculated based on the value of other parameters. When you modify the dimensions, the entire model geometry can update according to the relations you created. FEATURE-BASED MODELING

Parametric modeling systems are often referred to as feature-based modelers. In a parametric modeling environment, parts are composed of features (Fig.). Features may comprise either positive space or negative space. Positive space features are composed of actual mass. An example of a positive space feature is an extruded boss. A negative space feature is where a part has a segment cut away or subtracted. An example of a negative space feature is a hole. Parametric modeling systems such as Pro/ENGINEER incorporate an intuitive way of constructing features. Often, the feature is first sketched in two dimensions and C.O.E & T, Ak ola.

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then either extruded, revolved, or swept to form the three-dimensional object. When sketching the feature, design intent is developed in the model by adding dimensions and constraining the sketch. Features can be predefined or sketched. Examples of predefined features include holes, rounds, and chamfers. Many parametric modeling packages incorporate advanced ways of modeling holes. Within a parametric modeling package, predefined holes can be simple, counter bored, countersunk, or drilled. Parametric modeling package hole command allows users the opportunity to sketch unique hole profiles, such as may be required for a counter bore. Sketched features are created by sketching a section that incorporates design intent. Sections may be extruded, revolved, or swept to add positive or negative space features.

Fig. : Feature in a model Compared to Boolean modeling, feature-based modeling is a more intuitive approach. In Boolean modeling, a common way to construct a hole is to model a solid cylinder and then subtract it from the parent feature. In a parametric design environment, a user can simply place the hole by using a predefined hole command or by cutting a C.O.E & T, Ak ola.

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circle through the part. With most Boolean-based modelers, if the user has to change a parameter of the hole, such as location or size, he or she has to plug the original hole, then subtract a second solid cylinder. To adjust a feature-based hole, the user can change any parameter associated with the hole by modifying a dimension or parameter. Similarly, a feature's sketch can be redefined or modified. You create models in Pro/ENGINEER by building features. These features have intelligence, in that they contain knowledge of their environment and adapt predictably to change. Each features asks the user for specific information based on the feature type. For example, a hole has a diameter, depth, and placement, while a round has a radius and edges to round. ASSOCIATIVITY

Pro/ENGINEER is a fully-associative system. This means that a change in the design model anytime in the development process is propagated throughout the design, automatically updating all engineering deliverables, including assemblies, drawings, and manufacturing data. Associativity makes concurrent engineering possible by encouraging change, without penalty, at any point in the development cycle. This enables downstream functions to contribute their knowledge and expertise early in the development cycle. ENGINEERING GRAPHICS

The fundamentals of engineering graphics and the displaying of threedimensional (3D) designs on a two-dimensional surface have changed little since the advent of CAD. Despite the explosion of advanced 3D modeling packages, many design standards and techniques that once dominated manual drafting remain relevant today.

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Sketching is an important tool in the design process. Design modeling techniques using two-dimensional CAD, three-dimensional CAD, or manual drafting can restrict an individual’s ability to work out a design problem. It takes time to place lines on a CAD system or to construct a solid model. Sketching allows a designer to work through a problem without being constrained by the standards associated with orthographic projection or by the time required to model on a CAD system. There are two types of sketching techniques: artistic and technical. Many individuals believe that artistic sketching is a natural, inborn ability. This is not always the case. There are techniques and exercises that engineering students can perform that will improve their ability to think in three dimensions and solve problems utilizing artistic sketching skills. Despite this, few engineering students receive this type of training. When engineering or technology students are trained in sketching, it is usually the technical variety. Technical sketching is similar to traditional drafting and twodimensional computer-aided drafting. This form of sketching enables a design to be displayed orthographically or pictorially through sketching techniques. The design process requires artistic sketching and technical sketching to be utilized together. Conceptual designs are often developed through artistic sketching methods. Then once a design concept is developed, technical sketches of the design can be drawn that will allow the designer to display meaningful design intent information. This information can then be used to develop orthographic drawings, prototypes, and/or computer models. The traditional way to display engineering designs is orthographic projection. Any object has six primary views These views are used to display the three primary C.O.E & T, Ak ola.

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dimensions of any feature: height, width, and depth. By selectively choosing a combination of the primary views, a detailer can graphically display the design form of an object. Often, three or fewer views are all that are necessary to represent design intent. A combination of views such as the front, top, and right side will display all three primary dimensions of any feature. By incorporating dimensions and notes, design intent for an object can be displayed. Orthographic projection is not a natural way to display a design. The purpose for orthographic drawings is to show a design in such a way that it can be constructed or manufactured. Pictorial drawings are often used to represent designs in a way that nontechnically trained individuals can understand. Pictorial drawings display all three primary dimensions (height, width, and depth) in one view. There are many forms of pictorial drawings, the most common of which are isometric, diametric, and trimetric. Naturally, objects appear to get smaller as one moves further away from them. This effect is known as perspective. Perspective is another form of pictorial drawing. Orthographic, isometric, diametric, and trimetric projections do not incorporate perspective. Perspective drawings are often used to display a final design concept that can be easily understood individuals with no technological training. Before an object can be manufactured or constructed, technical drawings are often produced. Technical drawings are used to display all the information necessary to properly build a product. These drawings consist of orthographic views, dimensions, notes, and details. Details are governed by standards that allow for ease of communications between individuals and organization.

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PARAMETRIC MODELING CONCEPTS Parametric modeling is an approach to computer-aided design that gained prominence in the late 1980s. An assumption commonly held among CAD users is that similar modeling techniques exist for all CAD systems.

To users that follow this

assumption, the key to learning a different CAD system is to adapt to similar CAD commands. This is not entirely true when a two-dimensional CAD user tries to learn, for the first time, a parametric modeling application. Within parametric modeling systems, though, you can find commands that resemble 2D CAD commands.

Often, these

commands are used in a parametric modeling system just as they would be used in a 2D CAD package. The following is a partial list of commands that cross over from 2D CAD to Pro/ENGINEER. LINE The line option is used within Pro/ENGINEER’s sketcher mode (or environment) as a tool to create sections. Within a 2D CAD package, precise line distances and angles can be entered using coordinate methods, such as absolute, relative, and polar. Pro/ENGINEER does not require an entity to be entered with a precise size. Feature size definitions are established after finishing the geometric layout of a feature’s shape. CIRCLE As with the line command, the circle option is used within Pro/ENGINEER’s sketcher environment. Precise circle size is not important when sketching the geometry.

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ARC As with the line and circle options, the arc command is used within Pro/ENGINEER’s sketching environment. Pro/ENGINEER’s are command also includes a fillet command for creating rounds at the intersection of two geometric entities. DELETE The delete command is used within a variety of Pro/ENGINEER modes. Within the sketcher environment, delete is used to remove eometric entities such as lines, arcs, and circles. Within Part mode, delete is used to remove features from a part. For assembly models, the delete command is used to delete features from parts and to delete parts from assemblies. OFFSET Offset options can be found within various Pro/ENGINEER modes. Within the sketcher environment, existing part features can be offset to form sketching geometry. Additionally, planes, within Part and Assembly modes can be offset to form new datum planes. TRIM The trim command is used within Pro/ENGINEER’s sketching environment. Geometric entities that intersect can be trimmed at their intersection point. MIRROR The mirror option is used within Pro/ENGINEER’s Sketch and Part modes. Geometry created as a sketch can be mirrored across a centerline. Also, part features can be mirrored across a plane by executive the copy option.

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COPY The copy option is used within Part mode to copy existing features. Features can be copied linearly, mirrored over a plane, or rotated around an axis. Within Assembly mode, parts can be copied to create new parts. ARRAY Polar and rectangular array commands are common components in 2D CAD packages. Pro/ENGINEER’s pattern command serves a similar function. Features may be patterned using existing dimensions. Selecting an angular dimension will create a circular pattern. Parametric modeling presents a different approach to CAD, especially when compared to 2D drafting and Boolean-based 3D modeling. Oftentimes an experienced CAD user will have trouble learning a parametric modeling package. This is especially true when a user tries to approach 3D parametric modeling as he or she would approach Boolean solid modeling. They use similar concepts, but the approaches are different.

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ABOUT MECHANISM The descriptions of mechanisms designed by us are given below. 1. SLINDING PAIR: When two element of a pair are connected in such a way that one can only slide relative to the other the pair is known as sliding pair. 2. TURNING PAIR: When the two element of a pair are connected in such a way that one can only turn or revolve about a fixed axis to another link the pair is called Turning pair. 3. CHAIN DRIVE: The chain drives are mostly used to transmit and power from one shaft to another shaft when the distance between the center of the shaft is short. 4. CAM WITH OFFSET FOLLOWER: A cam is a rotating machine element which gives reciprocating or oscillating motion to other element known as follower and when the motion of the follower is along an axis away from the axis of cam centre. It is called off set follower. 5. SCREW PAIR : When the two elements of a pair are connected in such a way that one element can turned above the other by screw thread. The pair known as screw pair. 6. FRICTION DISC :The friction disc running without slip and toothed gearing are identical by you to the Pomibility of plexping of disc, are friction disc can only used for transmission of small power.

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7. BAND BLOCK BRAKE: The band brake may be lined with blocks of wood are other material the friction between the block and drum provide to breaking action. 8. EPICYCLOID GEAR: The epicycloid gear are useful for transmitting high velocity ratio with gear of moderate size in a comparatively lesser space. The epicyclic gear are used in the back gear of lathe. In Epicycloid gear one gear is fixed and another gear is forced to rotate upon the another gear. 9. OLDHAM'S IS COUPLING: An oldham's coupling is used for connecting to parallel shaft whose axes are at smaller distance apart. The shafts are coupled in such a way that if one shaft rotates, the other shaft also rotates at the same speed. 10. INTERNAL EXPANSION BRAKE: An internal expanding brake consist of two shoes. The outer surfaces of the shoes are linked with some friction material to increase the coefficient of friction and to prevent wearing away of the material. 11. CYCLOTIAL GEAR: In this a curve is traced by a point on the circumference of a circle, which rolls without slipping on a fixed straight line. When circle roll without slipping on the outside of a fixed circle the curve traced by the point on the outside of a fixed circle is known as epi-cycloid and if it rolls inside the circumference of circle is called hypocycloid.

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12. WHITWORTH QUICK RETURN MECHANISM :It is an inversion of single slide crank chain. This mechanism is mostly used in shaping and slotting machines. 13. OSCILLATING CYLINDER MECHANISM: It is also an inversion of single slider crank chain. This mechanism is used to convert reciprocating motion into rotary motion. 14. SINGLE STAGE HELICAL GEAR: A helical gear has teeth in the form of helix around the gear. Two such gears may be used to connect two parallel shafts in place of spur gear. The teeth of helical gears with parallel axis have line contact, as in spur gearing. This provides gradual engagement and continuous contact of the engaging teeth. Hence helical gear give smooth drive with a high efficiency of transmission. In case of single stage helical gear, there is some axial thrust between the teeth, which is a disadvantages. In order to eliminate this axial thrust, double helical gears are used. 15. CAM WITH KNIFE EDGE FOLLOWER :When the contacting end of the follower has a sharp knife edge, it is called a knife edge follower. The sliding motion takes place between the contacting surfaces. In knife edge follower, a considerable thrust exist between the follower and the guide. 16. CAM WITH SPHERICAL FACED OR RECIPROCATING FOLLOWER: When the contacting end of the follower is of spherical shape, it is called a spherical faced follower.

It may be noted that when a flat faced follower is used in

automobile engines, high surface stresses and produced in order to minimize these

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stresses. The flat end of the follower is machined to spherical shape. When the follower reciprocates in guides as the cam rotates uniformly it is known as reciprocating follower. 17. SINGLE SHOE BRAKE: - It consist of a block or shoe which is pressed against the rim of a revolving brake wheel drum. The block is made of softer material than the rim of the wheel. This type of brake are commonly used on train and tram cars. 18. BEVAL GEAR: - The two non parallel or intersecting but co-planer shaft connected by gear. These gears are called beval gear. 19. SPIRAL GEAR :- Spiral gear are used to connect and transmit motion between two non parallel and non intersecting shaft. The pitch surface of the spiral gear are cylindrical and the teeth have point contact.

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NEED OF MULTIMEDIA IN EDUCATION At first sight, interactive multimedia should offer the same benefits to school pupils as it does to adult trainees. Lessons can be structured to individual requirements, students can control their rate of learning and retention rates can be increased. Interactive videodisks have been used in European schools since the early 1980s. The first and best known project in the UK was the BBC's Domesday system -a set of two disks that contained data on the life of the United Kingdom in the 1980s. An optical disk player was developed, together with the Laser Vision ROM (LV-ROM) format for interactive videodisks. Despite this early interest the use of multimedia in schools remains low. The costs of hardware and software have been a deterrent. Early government-funded programmes, such as the Interactive Video in Schools (IVIS) project sponsored by the Department of Trade and Industry, have probably caused more harm than good by encouraging schools to invest in platforms that are now outmoded. More recently there have been governmentsponsored programmes in France, Spain and the United Kingdom to get CD-ROM drives into schools. The National Council for Educational Technology (NCET), a governmentfunded body which promotes technology in education, is enthusiastic about the use of CD-ROM and multimedia to give pupils access to source material, such as newspapers from a particular period, so that they do not have to rely on opinions of teachers or textbooks. However, the plethora of different compact disk formats will continue to confuse and dismay would-be purchasers.

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In American schools videodisks are seen as a source of information, to be used with a remote control unit or bar-code reader to control the player, instead of a computer. This approach allows teachers and students to create and use interactive workbooks in the classroom, whilst avoiding the expense and complexity of the European systems.

a)_New developments in distance learning Distance learning reverses the normal approach to training. Instead of the trainees traveling to a training centre to meet the trainer, the training is brought to the trainees who are remote from the trainers and source of training materials. Distance learning courses are based on text, supported by a wide range of other media - audio- and videotape, radio and TV broadcasts - and occasional meetings with tutors. In future wide area communications will also be used to give students on-line access to their tutors. The teaching of surgery - like many branches of medicine - is heavily dependent on conveying visual information. One pilot project is designed to use facilities at University College London to enhance the teaching of surgery at other hospitals. Super JANET is used to relay surgical demonstrations from the operating theatre and clinical demonstrations from the lecture hall. The project is also exploring ways to enhance existing courseware in a distance learning environment.

b) The Multimedia Teleschool The CEC is encouraging the growth of training in Europe through the DELTA (Developing European Learning Through Technological Advance) programme.

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DELTA II has an emphasis on market-oriented projects. One of these is the Multimedia Teleschool (MTS) for European personnel development, whose aim is to develop a large, complex and realistic scenario for the application of advanced telecommunications technologies in corporate training. The MTS project will merge traditional distance training techniques with telematics (the integration of computing and telecommunications technologies). Its first phase was based on existing telecommunications technologies - public networks and direct broadcast by satellite (DBS). For example, the Berlitz Teleschool project runs a course in English for telecommunications. A computer conferencing system on the host computer in Berlin delivers a series of regular study letters to each student's personal computer at their workplace. Students use the same system to return completed assignments to their tutors. This is supplemented once a fortnight by a live satellite broadcast by a panel of experts. The participants in their workplaces are linked with each other and with their tutors. Questions and contributions are sent on-line by the students to the tutors, who either respond online or pass them on to the experts at the TV studio. Students benefit from being able to communicate with fellow students and experts throughout Europe. In the second phase of MTS these facilities are being extended to include basic rate ISDN to support facilities such as:  A direct connection between the tutor's computer and that of the student for interactive remote tutoring;  Videoconferencing between the tutor and students at different sites for interactive distributed learning;

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 Delivery of CBT packages onto the corporate LAN via a training, delivery and administration server;  Remote distance control of local resources such as CD-ROM on end user machines. The result will be a computer-mediated multimedia communication system with voice, images, video and data annotation. Students will be able to interact with their tutor and with each other. RUNNING PRO/ENGINEER WITH DEFAULT SETTINGS The best way to learn Pro/ENGINEER is to run the product using the default settings installed on your system. Once you are familiar with the ways these defaults operate, you can easily change them according to your needs. In this section you will learn how to start Pro/ENGINEER from the operating system and from the Application Manager, retrieve an object, and save your work when you exit Pro/ENGINEER. Later sections in this chapter provide detail on how to use the Application Manager, Model Tree, and startup configuration options to customize Pro/ENGINEER.

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CONTENTS OF CD  Project Report  Virtual Models  Seminar Reports of Projectees.  Troubleshooting  Information about projectees.  Information about guide.  Information about expert guide.  Information HOD.

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STORAGE CD-ROM Tutorial CD-ROMs are one of the most commonly used mediums for transporting and transferring software from computer to computer. CD-ROMs are an essential part of a computer as well as a great tool for use in educational settings. In this tutorial, you'll learn a little bit about CD-ROMs: •

What is a CD-ROM?

•

How to use a CD-ROM?

•

What can a CD-ROM offer education? To examine a topic, click on one of the links below. When you finish with

a section return to this Table of Contents.

What is a CD-ROM? A CD-ROM is a computer peripheral or attachment that is used to read CDs (compact discs). CD-ROM stands for Compact Disc - Read Only Memory. There are basically 2 types of CD-ROM drives: 1. Internal CD-ROM Drives. These drives are placed inside the case of your computer. 2. External CD-ROM Drives. These drives are placed outside of your computer and are connected to your computer via a cable. External CD-ROM drives resemble portable CD Players, such as those available for cars. C.O.E & T, Ak ola.

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There are no functional differences between internal and external CDROM drives. The major difference between the two is that of portability. The external CD-ROM drive you can unplug and take it with you. The internal one would require you to dismantle your computer and remove the drive in order to move it from one computer to another. The other major difference is in the price of the two different models. External CD-ROM drives cost slightly more than the internal ones. As mentioned earlier, CD-ROMs are the now the easiest vehicle for transporting computer files and software. CD-ROMs are continuously being improved upon; the main improvement involves the speed of the CD-ROM drive. The first CDROM drive released was a Single Speed (1X) Drive. Soon after its release the Double Speed (2X) CD-ROM Drive was released. Currently there are Fourteen Speed (14X) CDROMs available, as well as Multiple CD-ROM drives also known as CD Changers. CD Changers are very similar to multiple CD audio players. A CD Changer is a CD-ROM drive that can hold more than one compact disc. There are currently 4 - 6 - 12, & 16 Disk CD Changers on the market, although the price on the newer models is quite steep. A CD Changer is a CD-ROM Drive that can hold more than one CD. CD Changers can hold anywhere from 2 to 16 different CDs, but can only access one CD at a time. These drives are best used in a network setting in which you partially install several programs on a server that require the CD to be present in order for the program to function. This will allow users to access a main server and use whichever program they need at the time. This allows users to free up personal Hard Drive space that is being used to store large software programs.

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Advantages of CD-ROMs 1. CD-ROMs have many advantages over other disk drives such as: 2. A CD-ROM Drive can read both computer CD's as well as Audio CD's. (A Special "player" application is needed to preform this function.) 3. Newer Computer Programs are being released on CD's that will work on both IBM and Macintosh platforms. 4. A CD can hold up to 650 Megabytes, newer CDs can hold up to 1.2 gigabytes, of data compared to 1.44 megabytes of data on a floppy disk. This is approximately 250,000 pages of text. 5. Data stored on CD-ROMs can't be altered or deleted. 6. CD's are generally safe from computer viruses. 7. Data stored on a CD is digital versus analog data on Laser discs, thus picture and sound quality are increased as well as the amount of data that can be stored. 8. Quality of data on a CD is better than other tyes of storage media.

Disadvantages of CD-ROMs 1. CD-ROMs can pose problems to users as well, such as: 2. CD-ROM drives are about 10 - 20 times slower than a Hard Drive. 3. CD-ROM drives and Compact Discs are more expensive than other disk drives and other storage media.

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How to use a CD A CD can hold up to 650 Megabytes of data; a vast amount compared to standard diskettes. In order to run the programs from a CD most of them require you to install at least part of the program. This usually consists of movies and sounds as well as other required files. This helps increase the speed of the program. Movies and sounds can play faster and clearer from a hard drive than from a CD-ROM drive. When you install a software program, you generally have a choice of how to install the program. These choices are: 1. Minimal - Installs only those files that are absolutely necessary to make the program function. 2. Recommended - Installs movies, sounds, and other files that the Manufacturer believes will help the CD run. 3. Full - Installs most of program to your hard disk. This installation will usually help the program to perform at its best, but will use a larger amount of disk space. The only differences in these 3 types are related to the speed and performance of the program. When installing the program, choose the setup that will most benefit your needs. (e.g., - If you only have a 400 megabyte hard drive, it would not be recommended to perform a full installation of a CD.)

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Installation To setup or install a CD to your hard Drive, you will follow the same basic commands that you would follow to install any other software. To install a CD Program on an IBM or Compatible Machine running Windows Version 3.x follow these steps. 1. Insert the CD into your CD-ROM drive. 2. From the File Menu click Run. 3. Browse to the CD-ROM Drive, and select the Installation File located on the CD. (usually called Setup or Install). 4. Then follow the directions the program displays. To install a CD Program on an IBM or Compatible Machine running Windows Version 95, follow these steps. 1. Insert the CD into your CD-ROM Drive. 2. Click the Start button. 3. Select Run. 4. Browse to the CD. 5. Click the Installation File (usually Setup, or Install). 6. Follow the directions the program displays. NOTE - On many CD's that are used with Windows 95, there is a special feature installed on the CD, called the autorun feature. The autorun feature automatically brings up a window for that CD. In this window are usually 3 prompts:

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1. Install the program. - This will take you through the Installation Procedure. 2. Run the program - This will run the program if it has already been installed. 3. Exit or close the window - This will close the window and return you to your desktop.

To Install a CD Program on a Macintosh Computer follow these steps. 1. Insert the CD into the CD-ROM Drive. 2. Wait for the CD Icon to appear on the Desktop. Double click the CD icon. 3. From the CD window click the Installation File and 4. Follow the directions from the program. One thing that you will probably want to remember is that most CDs require you to have the CD in the CD-ROM drive when you run the program, especially those programs that have not been fully installed.

Using CD-ROMs in the Schools and colleges. CD-ROMs have many possibilities that benefit students and teachers. There are many educational programs and educational utilities currently available on Compact Discs that may be used in the calssrom. Many items (programs, files, pictures, etc.) that were too large to be put on a disk or too large to be replicated on multiple machines are now available on a Compact Disc.

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Educational uses of CD-ROMs Databases

Encyclopedias

The CIA World Factbook Encarta

How the Leopard got his Spots

The Magic School Bus

Grollier's Encyclopedia

SIM Earth

Encarta

SIM Planet

Brittanica Encyclopedia

SIM Isle

Interactive Story Books Instructional Software Just Grandma & Me

Simulations

Information & Investigative Software

Carmen SanDiego

Dinosaur

Oregon Trail

Oceans

Math Blaster

Dangerous Creatures

There are literally hundreds of educational titles available on CD-ROM. These titles are just some examples of CDs that you might use in your classroom. The following sites may be helpful in learning about and finding more information about CDROM titles that are currently available.

Compact disk-read-only memory (CD-ROM) CD-ROM is an extension of the CD-DA technology that can support up to 550 MB of pre-recorded digital data. A standard for CD-ROM - known as the Yellow Book - was announced by Philips and Sony in 1985. Mode I is for computer data. Mode 2 C.O.E & T, Ak ola.

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is for compressed audio data, image and video data. CD-ROMs (identifiable by the words 'data storage' beneath the logo) are best suited for the storage of text, but can support still image, graphics and audio if these are used separately - it is not possible to have commentary over pictures, for example. CD-ROM is operating system dependent - different versions are required for MS- DOS and the Macintosh, for example. The directory format is covered by an ISO standard (IS 9660) - formerly known as the High Sierra standard. Level One is similar to an MS-DOS file system, with restrictions on filenames and directory names. Level Two allows longer filenames, up to 32 characters, whilst retaining many of the other restrictions. Level Two disks are not usable on some systems, particularly MS-DOS. Most CD-ROMs intended for the Macintosh are created in the Hierarchical Filing System (HFS) format, which is unrelated to High Sierra and IS 9660 formats. CD-ROM is an economic medium for the publication and distribution of information. CD-ROMs are usually made by specialist companies who will make a master and then use that to duplicate the disks. Microsoft, Philips and Sony. It supports simultaneous text, still image and audio together with some motion video - partial screen, 15 fps. A supplement to the Yellow Book published in 1991 defines the CD-ROM XA standard, including a new kind of track that may interleave Mode 2 compressed audio and Mode 2 data sectors. Additional hardware is needed to separate these when playing the disk. The hardware is programmed to separate the audio from the data, decompress the audio and play it out through the audio jacks. At the same time, the hardware passes the data to the computer. It requires a Mode 2 CD-ROM drive and upgrade card. C.O.E & T, Ak ola.

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CD-ROM XA is the link between the workstation environment supported by CD-ROM and the consumer environment. It uses the same sound formats as CD-I (ADPCM levels B and C), but different graphics formats and operating systems. A special kind of CD-ROM XA bridge disk - Karaoke CD - was developed jointly by Philips and JVC. These disks can be played on a dedicated Karaoke CD player or on a CD-I player equipped with a Digital Video cartridge. This concept was developed further in the White Book specification for Video CD, another CD-ROM XA bridge disk. These disks, typically containing films or music videos, can be played on a dedicated Video CD player, on a CD-I player equipped with a Digital Video cartridge or on a computer equipped with the appropriate hardware and software. The Video CD standard is supported by Philips, JVC, Sony and Matsushita. Both Karaoke CD and Video CD support FSFM video with CD-quality audio, using the MPEG-I compression standard.

Compact disk-interactive (CD-I) In June 1987 Philips, Sony and Matsushita published a new standard, the Green Book, for CD-I - a self-contained multimedia system based on compact disk and compatible with existing CD audio technology. At its launch CD-I supported text, graphics, four levels of audio including CD-DA, still video and partial screen video. Support for FSFM video to the White Book specification can now be provided by equipping the CD-I player with a Digital Video cartridge. CD-I is a self-contained computer system, with its own processor unit based on the Motorola 68020, with specific video, audio and control hardware and a CD drive. It runs a real-time, multitasking operating system called CD-RTOS, based on the OS-9 operating system from Microware. A standard TV display is used for output. CD-I is a consumer product, aimed at repeating C.O.E & T, Ak ola.

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the success of CD-DA, so a CD-I disk will play on any CD-I player anywhere in the world. All CD-I players can play CD-DA disks and CD-I disks can contain CD-DA tracks. A variety of players, designed for different markets, are available from Philips and Sony. These include:  Consumer players such as the CD-I 220 are intended for home use and are sold through retail outlets;  Professional players such as the CD-I 360 have specific features, such as This topic stars by outlining the real and potential uses of video. Current use is largely confined to audiovisual material stored on analogue videodisk and played back as part of training or POI/POS applications. In future real-time video communications will be available on personal computers. The chapter then goes on to describe the technology and components that are required to capture and compress video images, including conversion to and from broadcast TV standards. It closes with a review of the most important international standards: the H.320 family for audiovisual telephony and MPEG for stored audiovisual applications. Proprietary techniques such as DVI are also included.

# AUDIO FILE FORMAT This project outlines some of the uses of audio in multimedia applications. It then describes the requirements for music and speech, together with an explanation of the methods used to capture and encode audio. The chapter closes with a review of the international standards that are relevant to audio telephony and audiovisual applications.

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Audio applications The audio side of multimedia has attracted relatively little attention in the computer industry. This is partly because of the massive publicity devoted to video. It may also be because the use of audio in business information systems is not clear. The existing multimedia platforms that support audio seemed designed for the entertainment market.

Despite this neglect, audio clearly has an important role in multimedia

applications. Special effects, such as music and voice, can be added to applications, especially training and point-of-sale or point-of-information systems.

A voice

commentary can be used to narrate what is happening on-screen or to highlight and reinforce key concepts. Combined with still pictures or animations, it can be used to explain an idea or a process to the user in a more effective way than text or graphics alone. Music can be used to attract customer attention or to create a particular mood. A huge volume of audio material already exists on records, tapes and compact disks. However, almost all of this will require copyright clearance before it can be used. Existing legislation such as that covering performing rights for music that is played in public areas may be unsuitable for new multimedia applications. A point-of-sale system, for example, might contain a large number of short musical extracts. It would be difficult and very costly to identify when each extract was played and make the requisite royalty payments. Libraries of sound clips can be purchased, free of copyright, for such applications. However, application developers may prefer to generate their own audio material.

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In some specialised areas audio on its own may form the core of a multimedia application. One such example is the provision of systems to help visually handicapped people. A recent project involved the downloading of a daily newspaper to a special terminal in the user's home. Here he or she could choose to listen to a speech processing system read selected articles aloud or have them displayed in a large typeface on the monitor. As costs come down and the technology improves, interest in using speech processing and recognition in more general business applications will increase. It is already possible to use simple commands to control a computer as part of the user interface.

Audio capture A sound digitiser is used to capture and digitise analogue sound from audiotape, cassettes, records, CD-ROM and the original audio version of compact disk known as CD-DA (compact disk-digital audio). Alternatively original music can be recorded using a microphone or composed on instruments that are attached to the computer through a MIDI interface. Once captured, audio is then stored on hard disk or optical media and can be edited and played back through speakers connected to the computer or through a headset. Many computers are now equipped with built-in sound processors and speakers. However, externally powered speakers will provide higher sound clarity and volume. They will be needed if the audio source is a separate compact disk drive that needs to be attached to speakers and cannot play through the computer.

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Music on the computer A variety of tools are available to support musicians who want to compose and edit music using a multimedia system. These include sequencers, which record MIDI information rather than sound. This information can then be edited and sent back to the MIDI instruments for playback.

MIDI Musical Instrument Digital Interface (MIDI) is an industry-standard connection for computer and digital control of musical instruments. It provides a way to record, play back and synchronise the settings needed to control sound-producing devices.

Speakers

Digitise Computer Source

Fig. Configuration for sound system

MIDI coding is also used in some multimedia editing and control systems. MIDI includes standards for the hardware itself (for example, the cables and connectors) as well as for the electronic information in the form of MIDI messages that are sent from one device to another. A computer with a MIDI interface can be used to control other

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MIDI-compatible devices through a MIDI port - a five-pin connection socket built into a device for connecting MIDI cables. There are three types of port: MIDI In receives data, MIDI Out sends data and MIDI Thru relays data without reading the message. The device also requires a microprocessor that is able to send and receive MIDI messages. These communicate musical events such as note-on/note-off or the pitch bend of a note. All systems must have at least one MIDI port with MIDI In, Out and Thru.

Voice on the computer The use of voice is likely to be far more important than music to most managers who want to develop multimedia information systems. Until recently this was not well catered for by suppliers. Suitable adapters and software are now available from several suppliers including Apple, Microsoft and Creative Labs. The Windows Sound System, for example, consists of a 16-bit audio card, microphone, headphones and a software application that Is designed to support business audio. It includes voice recognition (so that the user can teach it to recognise commands), voice synthesis, and support for importing sound clips into applications that make use of OLE. It also allows users to synchronise audio with digital video. Speech recognition technology, once used mainly by people who were unable to type due to physical disabilities, is now closer to being of practical use in the office. IBM has started to ship its Personal Dictation System for OS/2. In addition to supporting dictation at around 70 to 100 words per minute for text input, the system can be used to control the functions of the computer system and its applications. It can be trained to recognise the voice of an individual speaker uttering simple commands such as 'save file' and 'close window'. If speech recognition is to be used in business C.O.E & T, Ak ola.

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applications, then good acoustic conditions will be required to reduce ambient noise. Success rates are also affected by factors such as the size and composition of the vocabulary used, the attitude and speaking style of the user, and the type and placement of the microphone. Suitable applications are those that require relatively limited vocabularies in a quiet environment. They include inspections, sorting and visual monitoring where hands- free operation is required. A quiet environment will also be required for the use of video PCs in the office. Traditional videoconferencing equipment supports full duplex audio without echo. Picture Tel's IDEC technology, for example, adjusts the audio to maintain maximum sound quality without recalibration, allowing participants to move around the room. An enhanced version is provided in the company's video PCs, designed to suppress unwanted background noise from air conditioning or fans in PCs.

Compression As human beings are more sensitive to variations in the quality of sound than in the quality of image, multimedia systems will be required to support high standards for audio. Techniques to encode audio information are already well developed. Sound consists of pressure differences in the air. A microphone picks up these differences and feeds them through an amplifier. This analogue signal is first digitised using an analogue to digital converter (ADC). The computer samples the input waveform at regular intervals and converts the amplitude to a binary code, using pulse code modulation (PCM). For speech the audio signal is sampled at 8 kHz (i.e. 8,000 times per second) and 8 bits - representing 256 different amplitude values - are used to code each C.O.E & T, Ak ola.

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sample. The technique of limiting the number of values in this way is known as quantisation. This method of encoding will generate a stream of 64,000 bits per second (written as 64 Kbit/s), which needs to be put into packets for transmission over a network. For music of the quality provided by compact disk, the signal is sampled at 44.1 kHz (i.e. 44,100 times per second) and 16 bits are used to code each sample. In stereo this will generate a stream of 1.4 million bits per second (Mbit/s). Further compression can be achieved by suppressing silences or by better methods of coding: 1.

Non-linear PCM assigns the amplitude value points non-linearly. For example, a logarithmic scale can be used to assign codes more sparsely at the maximum amplitudes and more densely near the zero-crossing point.

2.

Differential PCM (DPCM) encodes the differential of the signal instead of the signal itself. The range of differentials is usually smaller than the range of amplitudes.

3.

Adaptive DPCM (ADPCM) dynamically adjusts the range of amplitude values to match the expected range of amplitudes in the input data stream.

# VIDEO FILE FORMAT Applications The launch of audiovisual applications on personal computers has attracted much attention. The use to which this technology will be put in the future is

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rather less clear, although some early experiments point the way. We can think of video applications in two groups: playback of stored audiovisual material and real-time audiovisual communications. The first group is well established. Training applications based on interactive videodisk have incorporated analogue video sequences as a standard technique. Public information systems also incorporated video clips, often as a way of attracting the attention of the user. The use of digital video in networked systems is still restricted by the technical problems of transferring large volumes of time- dependent data. Possible applications include the use of servers to hold libraries of Audiovisual communications may be one-to-one, as for example in a meeting between two people, each of whom has a videophone or video camera mounted on a personal computer. Compared to conventional videoconferencing equipment, these personal video systems seem rather limited. The combination of a small image (a window on a 14-inch monitor), low resolution and relatively slow frame rate means that current products are unlikely to satisfy users' requirements for lengthy face-to- face 'meetings' such as recruitment interviews where eye contact and body language are important. They could, however, be successfully used in situations where the discussion involves other forms of interaction. For example, a sales director might wish to contact sales executives in different cities. Each executive could display the latest forecasts on the computer, using a shared workspace. The quality of the video links is of secondary importance in this case. Real-time video communications may also be one-to-many. In this case only one person has a video camera; everyone else receives the video on their computers, C.O.E & T, Ak ola.

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as in a live broadcast.

This

latter approach is suitable for internal

company

communications - the company President's Christmas message, for example. More importantly it can form a part of a distance learning project. For example, in a university programme for US high schools that use personal computers for teaching the fine arts, the instructor can talk to students on remote locations via a real-time video link, as well as showing them still images of paintings.

Video capture Converting video for the computer Conventional broadcast TV, audio and video signals are analogue, whilst computers handle digital information. Multimedia systems need to be able to handle information in both analogue and digital forms, because: 1. Analogue video and audio signals may need to be converted into digital form so that they can be manipulated more easily. 2. Applications developed on computers may need to be converted back into analogue form for playback - from videotape, for example. 3. Analogue and digital forms may be combined in one application, as when a live television broadcast is run in a window on a computer screen, for example. Conversion between analogue and digital video presents a number of technical difficulties. The situation is complicated by the different and incompatible standards that have been adopted by the different industries involved. A TV screen may look superficially like a computer screen but it differs in a number of important ways. Most computers and some video systems use a component C.O.E & T, Ak ola.

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signal made up of three basic colours - red-green-blue (RGB) - that are individually controllable. Broadcast TV and most video systems use a composite signal in which luminance (brightness) and chrominance (colour), together with synchronisation information, are combined into a single signal. A decoder is needed to change a composite signal from a video source into an RGB signal for display on a computer screen. A complete image in a sequence of moving film or video is called & frame. In most broadcast video, the screen is interlaced. Two sets of alternating lines are broadcast. Even-numbered lines are drawn at one pass, odd-numbered lines are in a second pass. This allows an image to be broadcast at comparatively low frame rates (2530 fps) without excessive flicker. The eye averages similar values so the image remains clear. Computer screens, in contrast, are non-interlaced - video lines are presented sequentially. To compensate for this, frame rates are faster - 66.7 frames per second (fps) for the Macintosh, for example. Video resolution varies between broadcast standards - 625 lines for the US standard (NTSC) or 525 lines in Europe for the PAL and SECAM standards. In contrast, a computer with a VGA screen has a resolution of 640 x 480 pixels, with a 256-colour palette. On a television set the picture is extended to fill the entire screen, known as overscan, so that part of the picture at the edges is lost. Computer screens use underscan, in which the entire picture is visible, surrounded by a black border. So conversion from analogue to digital video requires a decoder to convert a composite video signal to an RGB signal and a scan converter to accelerate interlaced video for a non-interlaced computer screen. In addition if computer graphics are to be C.O.E & T, Ak ola.

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combined with the video signal, a synchronisation generator lock (genlock) will be required to combine the two. This allows the system to set its timing to match the timing of the video signal. Creating videos on the desktop The market for video adapters and related equipment has evolved rapidly. Each generation of products is swiftly overtaken by the next, as compression methods are improved, whilst at the same time proprietary techniques give way to developing international standards.

Video overlay boards The first generation of adapter boards provided overlay and genlock facilities - the ability to combine broadcast quality analogue video with computergenerated text and graphics. They were designed for use with videodisk players. It was possible to mask part of the video image on-screen, so that the remaining part appeared to be playing in a window, surrounded by text. However, the image itself could not .be manipulated - its size and position thus remained constant. Digitisers These were followed by a range of digital video capture devices (digitisers or frame grabbers) that could be used to accept PAL or NTSC signals from a videodisk player, video cassette recorder or video camera, and digitise them. Single frames could be 'grabbed' and stored as still images. Some of these adapters could provide real-time manipulation of the video image, including the ability to change its size, position, brightness, saturation, contrast sharpness and hue. A full screen of video could be scaled to any size and placed anywhere on the screen, within a window if desired. C.O.E & T, Ak ola.

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Compression boards In 1989 Intel introduced a new proprietary compression technology for audiovisual applications called DVI. Intel itself supplied both processors and adapter boards for real-time compression and decompression. These compressors can take a data stream from a digitiser board, compress it and store it on hard disk in real time. Other suppliers brought out adapters of their own, using Intel's processor set. More recent products support the emerging international standards for image compression, JPEG and MPEG. Although JPEG is essentially a standard for still images, in practice it has proved to be popular for compressing motion video. This is because each frame is compressed separately, thus making frame-by-frame editing much simpler. Several suppliers sell adapters that support motion video to the JPEG standard (known as Motion JPEG) with synchronous audio.

Display Digitiser

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Sources

Computer

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Fig. Configuration for video system

TROUBLESHOOTING 1) CD not play Remedy : Clean the lens of your CD Rom, writer or DVD Rom with the help of lens cleaner CD.

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2) You cannot hear Sound or Music. Remedy : Check that your sound card is properly installed. Check whether the speaker are powered on an adjusted to audio able level. 3) Unable to see VRML Models Remedy : Install VRML plug in provided in the CD. Restart your computer and then try again. 4) Unable to see the complete page of multimedia Remedy : Your text size may not be adjusted properly to display the whole page. Goto view menu. View >> Textsize >> Smallest. 5) Cannot browse the content of CD properly Remedy : Update your internet explorer to at least version 6 or more 6) Unable to view a *.avi files Remedy : Install window media player or any other suitable media player (mp3 of Jet player) to view AVI files. 7) Cannot view *.max files

Remedy : Install 3DS Max 6 software.

8) Unable to view *.prt or *.asm files Remedy : Install Pro / E 2001 of Pro / E Wildfire Remember that the above version of Pro/E can be installed in Windows XP or later.

COSTING a) Investment costs Against the positive economic benefits outlined above must be set the high cost of implementing a multimedia system. Though the cost of technology is falling C.O.E & T, Ak ola.

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steadily, the cost of development work remains very high. Such work typically requires the assistance of one or more third party suppliers as very few organizations have the requisite design skills available in house. Experience shows that most managers underestimate the skills involved, the need for a new approach to product management and the length of development time. Unlike most other computer-based systems, multimedia involves a high proportion of information (usually referred to as its content) in a form that is very expensive to create and maintain. This is exacerbated in many cases by the need to pay royalties or fees to the owners of copyright, since the ownership of much audiovisual material is likely to lie outside the organization.

COST SHEET Operator Charges Rs. 10,000 @ Rs. 500/- per diagram x 25 Computer Charges C.O.E & T, Ak ola.

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@ Rs. 1300/- per month x 3 months Sound Recording C.D. Writing (Including Blank C.D.)

Rs. 600

50 per CD x 12 C.D. Cover and Cover page Rs. 504 42 x 12 Literature Summary Download of VRML Browsers

Rs. 200

Internet Charges Total

Rs. 15,204

Cost of single CD is 15204/12 = Rs.1267.

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CONCLUSION In this project we have basically worked on Pro / E for modeling different Mechanism of Theory of Machine. It is very hard to understand working of these mechanisms due to their complicated arrangement consisting various link and joints. We have used 3D Max Studio for the simulation of these mechanism by providing motion to them, it is much easier to understand the working of such mechanism and we have used VRML so that our work can be seen directly on web. Also we have opened this field for making such type of educational knowledge on the subjects, which are highly practical, boring and very difficult to understand only by reading. This project is just an extension of the project carried out by our guide and seniors " Educational multimedia on hydraulics and Pneumatics " before two years. The above project was a 2D representation of the problem whereas this project is a 3D representation. The concept of this project can be applied in mechanical engineering laboratories where the complex machines and mechanisms are displayed. The same concept is useful to the marketing people in machine tools industry where the models of actual machines can be demonstrated in absence of actual machines. Interactive 3D working models are always better than video films where we have a choice to see those things that we want to see. VRML out put of the project enables the models to be displayed on the web so that there is no need of carrying the CD-ROM. Even though the PRO/Engineer has the capability of simulation, the software was not used for this purpose because it might have put many constraints on the process.

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REFERENCE 1) LEARN VRML IN 21 DAYS BY: CHRIS MARRIN AND BRUCE CAMPBELL 2) THEORY OF MACHINE BY: R.S. KHURMI 3) PRO/E WILDFIRE BY :SHYAM TICKOO 4) Pro/ENGINEER INSTRUCTOR ( TATA McGRAW-HILL) BY : DAVID S. KELLEY. 5) MASTERING 3D MAX ( BPB PUBLICATIONS) BY : CAT WOODS ALEXANDER BICALHO CHRIS MURRAY. 6) www.google.com

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Acknowledgement It is the co-operation, mutual team sprit and delightful work, which bring the successful completion of our project work. It is only the precious guidance encouragement and inspiration provided by Prof. D.V. Shirbhate, which brought the enthusiasm and boosted our moral to complete the project. We are grateful and express our profound

gratitude for his help. We are also grateful to our

honorable H.O.D. Prof. C.V. Deshmukh for his guidance and timely help. He has come through on countless occasions to make sure that project gets completed in time. We would like to acknowledge Prof. S.K. Patil who spoke and demonstrated dedication to technical excellence. We would also like to thank Mr. Anirudha for his great hand in Digital printing and Web page designing which stand as pillar of our project. We would like to thank to great staff of our college without whom we would not be holding this project on our hands. In the last how we can forget our respected principal Dr. A.B. Marathe sir who has provided every facility for the completion of our project.

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INDEX 1) Abstract 2) About VRML 3) About 3DS MAX 4) About Pro / E 5) Parametric Modeling Concept 6) About Mechanism 7) Need of Multimedia in Education 8) Content of CD 9) Storages 10) Troubleshooting 11) Costing 12) Conclusion 13) Reference

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