COMPUTER AIDED DESIGN (2 MARKS QUESTION BANK) UNIT-I 1. Define Computer Aided Design. CAD is the function of computer systems to support in the creation, modification, analysis, or optimization of a design. CAD software is used to raise the productivity of the designer, progress the quality of design, progress communications through documentation, and to generate a database for manufacturing. 2. Define computer aided engineering Computer aided engineering is complemented by computer-aided design and computer-aided manufacturing.is a very powerful tool used in industries for ability to save time, drawing and to produce better designs with automatic machine tools by a specially prepared software used to run the computer. 3. Define design process The design process is a step by step manner from some statement of need through identification of the problem, a search for solution and development of the chosen solution to manufacturing, test and to use by a combination of principles, resources and products in design. 4. What are the various design process models? a. Shigley model b. Phal and beitz model c. Ohsuga model d. Earle model 5. What are the steps involved in the design process? a. Recognition of need b. Definition of problem c. Synthesis d. Analysis and optimization e. Evaluation f. Presentation 6. Define Recognition of need. Recognition of need involves the realization by someone that a problem exists for which some corrective action should be taken. This might be identification of some defect in current machine design by an engineer or the perception of a new product marketing opportunity by salesperson. 7. Write the analysis step of design process Synthesis and analysis are closely related and highly iterative in the design process. A certain component or subsystem of the overall system is conceptualized by the designer, subjected to analysis, improved through this analysis procedure and redesigned. The process is repeated until the design has been optimized within the constraints imposed on the designer. 8. What is evaluation? Evaluation is concerned with measuring the design against the specifications established in the problem definition phase. This evaluation often requires the fabrication and testing of prototype model to assess operating performance, quality, reliability and other criteria. 9. What is presentation? The final phase in the design process is the presentation of design. This includes documentation of the design by means of drawings, material specifications, assembly lists and so on.
10. Differentiate preliminary design and detailed design Preliminary design Detailed design The preliminary design fills the gap between the The next phase of preliminary design is the design concept and the detailed design phase. The Detailed Design which may includes of system configuration is defined, and schematics, procurement also. This phase builds on the diagrams, and layouts of the project will offer already developed preliminary design, aiming early project configuration. In detailed design and to further develop each phase of the project by optimization, the parameters of the part being total description through drawings, modeling produced will change, but the preliminary design as well as specifications focuses on creating the common framework to construct the project 11. What are the benefits of CAD system for the design engineer? a. Productivity improvement in design b. Shorter lead time. CAD system enables the designer to prepare a finished set of drawing and documentation in a relatively short time. c. Flexibility in design d. Improve design analysis e. Fewer design errors f. Standardization of design, drafting and documentation procedures g. Easier creation and correction of engineering drawing h. Easier visualization of drawing 12. What are the applications of CAD? a. Printed circuits design b. Computer aided process planning c. Piping systems for process industries d. Calculation of mass properties e. Finite elements of analysis f. Coding of parts and retrieval g. CNC programming h. Architecture building design i. Kinematic and dynamic analysis of mechanisms 13. State the importance of Computer Architecture in CAD. In CAD, Computer architecture is a set of disciplines that explains the functionality, the organization and describes the capabilities of a computer and its programming method in a summary way, and how the internal organization of the system is designed and executed to meet the specified facilities. 14. List out the components of cad system architecture a. Hardware b. Software c. Data d. Human knowledge and activities 15. Define concurrent engineering. Concurrent engineering is a method by which several groups within an organization work simultaneously to create new products and services.
16. What are the advantages of concurrent engineering? a. Both product and process design run in parallel and take place in the same time. b. Process and Product are coordinated to attain optimal matching of requirements for effective quality and delivery. c. Decision making involves full team involvement. 17. What are the components of computer hardware systems? a. Central processing units i. Memory unit ii. Arithmetic and logic unit iii. Control unit b. Input unit c. Output unit 18. What is a mass storage device? List out some of the devices The purpose of external storage is to retain data and programs for further use. Any number of files containing information can be stored on external media. • Floppy disc • Hard disc • Compact disc • Cartridge magnetic tape, digital audiotape 19. What is raster scan displays? The raster graphics involve the manipulation of the color and of intensity of points know as picture elements or pixels in a matrix making up the image and each pixel is in the rectangular matrix that covers the screen controlled. 20. What is stroke writing device? The stroke writing device draws vectors or line to create an image while a raster scan device uses a matrix of closely spaced dots (pixels) to form a picture. 21. List out the various display devices. a. Plasma display b. Light emitting diode(LED) c. Liquid crystal display(LCD) d. Electro luminescent panel 22. List out the various input devices a. Light pens b. Analogue devices i. Digitizer ii. Joystick iii. Trackerball iv. Dial v. Thumbwheels c. Keyboard devices i. Keyboards ii. Bottoms iii. Switches iv. Voice data entry system
23. List out the various output devices a. Printer i. Dot matrix printers ii. Ink jet printers iii. Electrostatic printers iv. Thermal printers v. Laser printer b. Plotter i. Pen plotter ii. Electrostatic plotter c. Hard copy unit d. Computer output to microfilm units UNIT –II 1. Define Bresenham’s algorithm Bresenham's algorithm is an algorithm that determines the points of an ndimensional raster that should be selected in order to form a close approximation to draw a straight line or circle in between two points. It is commonly used to draw lines or circle on a computer screen, as it uses only integer addition, subtraction and bit shifting. 2. Define transformation Geometric transformation provide a means by which an image can be enlarge in size or reduce, rotated or moved. These changes are obtained by changing the co-ordinates of the picture to a new set of values depending upon the requirements. 3. Define default co-ordinate The design package initiated the display will have set of co-ordinate values this are called as default co-ordinates 4. Define user co-ordinate A user co-ordinate system is one in which the designer can specify his own co-ordinates for a specific design application. 5. Define window The designer nay want to view only a portion of the image which is enclosed in a rectangular region is called window. 6. Define view port The different portion of the object can be view on the single region of the screen is called view port. 7. Define scaling. The image displayed can be reduced or enlarged using scaling. Scaling can be done either in x or y direction or in both directions simultaneously. Scaling factors can be specified in x and y directions to carry out scaling. 8. Define translation Translation is moving a drawing or model across the screen is called translation. This can be obtained by adding to the co-ordinate of each corner point of the drawing to new location. 9. Define rotation Rotation is used to rotate a drawing or model about a pivot point either in clockwise or anticlockwise direction to the required angle θ 10. Define shearing A shearing transformation produces distortion of an object or an entire image. It may be in two axis about x or y shear.