Engineering Design Graphics

1 ENGINEERING DESIGN 1 INTRODUCTION 1 ASPECTS OF ENGINEERING DESIGN 1 ANALYSIS AND DESIGN 4 PRODUCT ANATOMY 5 DESIGN PHASES 5 DESIGN PROCESS OVERVIEW 6 NEEDS ASSESSMENT 7 PROBLEM DEFINITION 7 BACKGROUND RESEARCH 7 DESIGN CRITERIA 8 DESIGN CONSTRAINTS 8 ALTERNATIVE SOLUTIONS 9 ANALYSIS 12 EVALUATION AND SELECTION 12 SPECIFICATION 16 COMMUNICATION 20 Written Reports 20 Recommended report-writing steps 20 Oral Presentations 21 BEGINNING VERSUS INFORMED DESIGNER PATTERNS (SIDEBAR) 23 CONCURRENT ENGINEERING 23 Design for Manufacture and Assembly 25 TEAMWORK 26 QUESTIONS 27 2 HUMAN-CENTERED DESIGN AND DESIGN THINKING 29 INTRODUCTION 29 ENGINEERING DESIGN, ART, AND SCIENCE Introduction Design: a fundamental human activity Engineering Design from 1400 to 1900 Engineering Education after 1900 TWO DESIGN PARADIGMS Design as rational problem solving Design as a reflective practice WICKED PROBLEMS DIVERGENT AND CONVERGENT QUESTIONING DOUBLE DIAMOND DESIGN PROCESS HUMAN-CENTERED DESIGN DESIGN THINKING Introduction Three spaces of innovation Inspiration Observation Empathy Ideation Empathy Ideation Brainstorming Prototyping Implementation Test and iterate T-shaped individuals (sidebar) Radical collaboration QUESTIONS 3 PRODUCT DISSECTION INTRODUCTION PRODUCT SUITABILITY PRODUCT DISSECTION PROCEDURE PRE-DISSECTION ANALYSIS DISSECTION Craftsman locking pliers disassembly steps PRODUCT DOCUMENTATION PRODUCT ANALYSIS PRODUCT IMPROVEMENT REASSEMBLY COMMUNICATION QUESTIONS 4 FREEHAND SKETCHING INTRODUCTION SKETCHING TOOLS AND MATERIALS SKETCHING TECHNIQUES Line Techniques Sketching Straight Lines Sketching Circles Sketching Ellipses PROPORTIONING Estimating Dimensions of Actual Objects Partitioning Lines INSTRUMENT USAGE—TRIANGLES Parallel Lines Perpendicular Lines LINE STYLES QUESTIONS 5 PLANAR PROJECTIONS AND PICTORIAL VIEWS PLANAR PROJECTIONS Introduction Classification of Planar Projections: Projector Characteristics Preliminary Definitions Block coefficient Classification of Planar Projections: Orientation of Object with Respect to Projection Plane Further Distinctions Between Parallel and Perspective Projections Classes of Parallel Projections OBLIQUE PROJECTIONS Oblique Projection Geometry Oblique Projection Angle Classes of Oblique Projections Oblique projection angle in 2D Receding Axis Angle ORTHOGRAPHIC PROJECTIONS Orthographic Projection Geometry Orthographic Projection Categories AXONOMETRIC PROJECTIONS ISOMETRIC PROJECTIONS Isometric Drawings Multiview Projections INTRODUCTION TO PICTORIAL SKETCHING OBLIQUE SKETCHES Introduction Axis Orientation Receding Axis Scale Object Orientation Guidelines Sketching procedure for a simple extruded shape (see Figure 5-37) Step-by-step cabinet oblique sketch example for a cut block (see Figure 5-38) Step-by-step cavalier oblique sketch example for an object with circular features (see Figure 5-39) ISOMETRIC SKETCHES Introduction Axis Orientation Isometric Scaling Isometric Grid Paper Object Orientation Guidelines Step-by-step isometric sketch example for a cut block (see Figure 5-46) Circular Features in an Isometric View Step-by-step isometric sketch example for a cylinder (see Figure 5-47) Step-by-step isometric sketch example for a box with holes on three faces (see Figure 5-48) Step-by-step sketch example for an object with circular features (see Figure 5-49) Chapter review: pictorial sketching scalability QUESTIONS 6 PERSPECTIVE PROJECTIONS AND PERSPECTIVE SKETCHES PERSPECTIVE PROJECTION Historical Development Perspective Projection Characteristics Classes of Perspective Projection Vanishing Points One-Point Perspective Projection Two-Point Perspective Projection Three-Point Perspective Projection Perspective Projection Variables Perspective projection using a 3D CAD system Projection plane location Lateral movement of CP Vertical movement of CP Varying distance from CP PERSPECTIVE SKETCHES Introduction Terminology One-Point Perspective Sketches Two-Point Perspective Sketches Proportioning Techniques Step-by-step one-point perspective sketch example (see Figure 6-26) Step-by-step two-point perspective sketch example (see Figure 6-27) Summary: orientation of pictorial sketching axes (see Figure 6-28) QUESTIONS 7 MULTIVIEWS MULTIVIEW SKETCHING Introduction—Justification and Some Characteristics Glass Box Theory Alignment of Views Transfer of Depth View Selection Third-Angle and First-Angle Projection Line Conventions Multiview drawing of a cylinder (see Figure 7-21) Line Precedence Generic three multiview sketch procedure (see Figure 7-24) Step-by-step multiview sketch example (see Figure 7-25) Intersections and Tangency 92 Fillets and Rounds Machined Holes Conventional Representations: Rotated Features Step-by-step multiview sketch example: object with complex features (see Figure 7-33) VISUALIZATION TECHNIQUES FOR MULTIVIEW DRAWINGS Introduction and Motivation Treatment of Common Surfaces Normal surfaces Inclined surfaces Oblique surfaces Projection Studies Adjacent Areas Surface Labeling Similar Shapes Vertex Labeling Analysis by Feature Missing-Line and Missing-View Problems QUESTIONS 8 SECTION AND AUXILIARY VIEWS SECTION VIEWS Introduction Section View Process Section Lining (Hatch Patterns) Full Sections Half Sections Offset Sections Broken-Out Sections Revolved Sections Removed Sections Conventional Representations: Section Views Conventional Representations: Thin Features Section View Construction Process—Example 1 Section View Construction Process—Example 2 Conventional Representations: Aligned Sections Assembly Section Views AUXILIARY VIEWS Introduction Definitions Auxiliary View Projection Theory Auxiliary Views: Three Cases General Sketching Procedure for Finding a Primary Auxiliary View Step 1 Step 2 Step 3 Step 4 (optional) Step 5 Step 6 Finding a Primary Auxiliary View of a Contoured Surface Finding a Partial Auxiliary View, an Isometric Pictorial, and a Missing View, Given Two Views QUESTIONS 9 DIMENSIONING AND TOLERANCING DIMENSIONING Introduction Units of Measurement Application of Dimensions Terminology Reading direction for dimensional values Arrangement, placement, and spacing of dimensions Using Dimensions to Specify Size and Locate Features Symbols, Abbreviations, and General Notes Dimensioning Rules and Guidelines Prisms Cylinders and arcs Finish Marks TOLERANCING Introduction Definitions Tolerance Declaration Tolerance Accumulation Mated Parts Basic Hole System: English Units Basic Shaft System: English Units Step-by-step tolerance calculation of a clearance fit using the basic hole system (see Figure 9-27) Step-by-step tolerance calculation of an interference fit using the basic hole system (see Figure 9-28) Preferred English Limits and Fits Running or sliding clearance fit (RC) Locational clearance fit (LC) Transition clearance or interference fit (LT) Step-by-step tolerance calculation of a clearance fit using the basic shaft system (see Figure 9-30) Locational interference fit (LN) Force or shrink fit (FN) Step-by-step tolerance calculation using English-unit fit tables, basic hole system (see Figure 9-31) Step-by-step tolerance calculation using English-unit fit tables, basic shaft (see Figure 9-32) Preferred Metric Limits and Fits Step-by-step tolerance calculation using metric-unit fit tables, hole basis (see Figure 9-39) Step-by-step tolerance calculation using metric-unit fit tables, shaft basis (see Figure 9-40) Tolerancing in CAD QUESTIONS 10 CAD: SOLID MODELING INTRODUCTION Computer-Aided Design Categories of CAD Systems Computer-aided drawing Solid modeling Topology (Sidebar) Parametric modeling Direct modeling Surface Modeling – NURBS and Freeform Building Information Modeling (BIM) (Sidebar) CAD Viewing and Display PARAMETRIC MODELING Introduction Terminology Part Modeling Introduction Sketch mode Feature creation Part editing Part creation process (see Figure 10-32) Assembly Modeling Introduction Joints CAD libraries Advanced Modeling Strategies Cloud-Based CAD QUESTIONS 241 11 CAD: NURBS AND FREEFORM SURFACE MODELING NURBS SURFACE MODELING Introduction Parametric Curves and Cubic Splines Parametric representation of a curve (sidebar) Bézier Curves B-Splines NURBS Surfaces Curvature Continuity Class A Surfaces FREEFORM SURFACE MODELING Introduction Polygon meshes and polygonal modeling Subdivision surfaces NURBS Limitations T-Splines The Bézier Award (Sidebar) QUESTIONS 12 PRODUCT DOCUMENTATION WORKING DRAWINGS Model-based definition DETAIL DRAWINGS ASSEMBLY DRAWING VIEWS BILL OF MATERIALS AND BALLOONS SHEET SIZES TITLE BLOCKS BORDERS AND ZONES REVISION BLOCKS DRAWING SCALE TOLERANCE NOTES STANDARD PARTS WORKING DRAWING CREATION USING PARAMETRIC MODELING SOFTWARE Extracting a detail drawing from a parametric part model (see Figure 12-16) Using existing part models to create an assembly model (see Figure 12-17) Extracting a sectioned assembly drawing (see Figure 12-18) Creating an exploded view (see Figure 12-19) Creating an exploded view drawing with parts list and balloons (see Figure 12-20) INDUSTRY SPOTLIGHT: FISKARS GROUP QUESTIONS 13 ADDITIVE MANUFACTURING INTRODUCTION AM TECHNOLOGIES Vat photopolymerization Material extrusion Powder bed fusion Material jetting CLASSIFICATION OF AM TECHNOLOGIES 3D PRINTER FILE FORMATS STL REPAIR TOOLS CHARACTERISTICS OF AM SYSTEMS Part orientation Support structure Hatch style LOW-COST AM Industrial category AM Professional category 3D printers Consumer (home and hobby, desktop) category 3D printers DESIGN FOR ADDITIVE MANUFACTURING Design for conventional manufacturing processes Design for AM QUESTIONS 9 3D SCANNING REVERSE ENGINEERING 3D SCANNING Introduction 3D Scanner Pipeline Mesh terminology 3D Scanning Technologies Contact-based scanners Noncontact scanners Laser triangulation Structured Light Reality Capture Photogrammetry Time of Flight Reverse Engineering Software Mesh reconstruction (or point processing) NURBS surface modeling from scan data Parametric CAD model from scan data QUESTIONS 15 SIMULATION UPFRONT ANALYSIS FINITE ELEMENT ANALYSIS Modeling and Meshing Boundary Conditions Contour plot Results FEA workflow GENERATIVE DESIGN Generative design workflow DYNAMICS SIMULATION SOFTWARE Dynamics Simulation Software Demonstration QUESTIONS A ANSI PREFERRED ENGLISH LIMITS AND FITS B ANSI PREFERRED METRIC LIMITS AND FITS INDEX 3 DRAWING SHEETS