Important Notes to the Process

Transcription

1 Unit 1: Design Process Overview: The engineering design process is a series of steps that engineering teams use to guide them as they solve problems. The design process is cyclical, meaning that engineers repeat the steps as many times as needed, making improvements along the way. Important Notes to the Process Step 1 Find the Problem: Consider your potential customer, and what they want and what problems might need to be fixed. Step 2 Brainstorm: Sit with your group and come up with ideas together. Step 6 Select an Approach: Find out how you are going to fix the problem with a good thought process. Use a decision matrix, which requires defining a set of criteria. Step 8 Model or Prototype: Make a model and refine it. Step 9 Test and Evaluate: Test your product and see how the general public reacts to it.

2 Unit 2- Sketches and Drawings Key Term Center Line Construction Line Dimension Dimension Line Definition A line which defines the center of arcs, circles, or symmetrical parts. lightly drawn lines to guide drawing other lines and shapes. A measurable extent, such as the three principal dimensions of an object is width, height, and depth. A line which represents distance. Extension line Documentation Drawing Hidden Line Isometric Sketch Leader Line Multi View Drawing Oblique Sketch 1. The documents that are required for something or that give evidence or proof of something. 2. Drawings or printed information that contain instructions for assembling, installing, operating, and servicing. A formal graphical representation of an object containing information based on the drawing type. A line type that represents an edge that is not directly visible. A form of pictorial sketch in which all three drawing axes form equal angles of 120 degrees with the plane of projection. Line which indicates dimensions of arcs, circles and detail. A drawing which contains views of an object projected onto two or more orthographic planes. A form of pictorial in which an object is represented as true width and height, but the

3 depth can be any size and drawn at any angle. Orthographic Projection Profile Shape Sketch Solid A method of representing three dimensional objects on a plane having only length and breadth. Also referred to as Right Angle Projection. An outline of an object when viewed from one side. A two dimensional contour that characterizes an object or area, in contrast to three dimensional form. A rough representation of the main features of an object or scene and often made as a preliminary study. A three dimensional body or geometric figure. Auxiliary View Cutting Plane Line Sectional View UNIT 3: Measurements & Statistics Key Term Definition Accuracy Caliper The degree of closeness of measurements of a quantity to the actual (or accepted) value. A measuring instrument having two adjustable jaws typically used to measure diameter or thickness.

4 Data Data Set Dot Plot Frequency Graph Histogram International System of Units (SI) Line Plot Mean Measure Median Mode Precision Scale Facts and statistics used for reference or analysis. A group of individual values or bits of information that are related in some way or have some common characteristic or attribute. See line plot. The rate at which something occurs over a particular period or in a given sample. A diagram showing the relation between variable quantities, typically of two variables measured along a pair of lines at right angles. A graph of vertical bars representing the frequency distribution of a set of data. An international system of units of measurement consisting of seven base units. A method of visually displaying a distribution of data values where each data value is shown as a dot or mark above a number line. Also known as a dot plot. A measure of center in a set of numerical data, computed by adding the values in a list and then dividing by the number of values in the list. To determine the size, amount, or degree of an object by comparison with a standard unit. A measure of center in a set of numerical data. The median of a list of values is the value appearing at the center of a sorted version of the list or the mean of the two central values if the list contains an even number of values. The value that occurs most frequently in a given data set. The degree to which repeated measurements show the same result. 1. A straight edged strip of rigid material marked at regular intervals and used to measure distances. 2. A proportion between two sets of dimensions used in developing accurate, larger or smaller prototypes, or models of design ideas.

5 Scatter Plot Significant Digits Standard Deviation Statistics A graph in the coordinate plane representing a set of bivariate data. The digits in a decimal number that carry meaning contributing to the precision or accuracy of the quantity. The distance of a value in a population (or sample) from the mean value of the population (or sample). Collection of methods for planning experiments, obtaining data, organizing, summarizing, presenting, analyzing, interpreting, and drawing conclusions based on data. Skills in Unit Linear Measurements 3.2 Unit Conversions 3.3 Making Linear Measurements (Caliper and tolerances) 3.4 Linear Dimensions 3.5 Applied statistics 3.7 Statistical Analysis in Excel 3.8 Precision Accuracy measurement 3.9 Statistics Quality Metric Prefixes Prefix Symbol Fraction Sci. Notation kilo k

6 deci d 1/ centi c 1/ milli m 1/ micro μ 1/ Accuracy vs Precision Accuracy is how close a measured value is to the actual (true) value. Precision is how close the measured values are to previous values.

7 UNIT 4: Modeling skills Key Term Annotate Assembly Assembly Drawing Computer Aided Design or Computer Aided Drafting (CAD) Design Brief Definition To add explanatory notes to a drawing. A group of machined or handmade parts that fit together to form a self contained unit. A drawing that shows parts of an item when assembled. 1. When used in the context of design: the use of a computer to assist in the process of designing a part, circuit, building, etc. 2. When used in the context of drafting: the use of a computer to assist in the process of creating, storing, retrieving, modifying, plotting, and communicating a technical drawing. A written plan that identifies a problem to be solved, its criteria, and its constraints. The design brief is used to encourage thinking of all aspects

8 of a problem before attempting a solution. Domain Extrusion The set of input values of a function. 1. A manufacturing process that forces material through a shaped opening. 2. A modeling process that creates a three dimensional form by defining a closed two dimensional shape and a length. 3D Feature Function Geometric Constraint Model Origin Plane Portfolio Prototype Range 1. A relationship from one set (called the domain) to another set (called the range) that assigns to each element of the domain exactly one element of the range. 2. The action or actions that an item is designed to perform. Constant, non numerical relationships between the parts of a geometric figure. Examples include parallelism, perpendicularity, and concentricity. A visual, mathematical, or three dimensional representation in detail of an object or design, often smaller than the original. A fixed point from which coordinates are measured. A flat surface on which a straight line joining any two points would wholly lie. A collection of documents selected for a particular purpose which may contain reflection on the contents of the documents or the related purpose. Varieties of portfolio types exist and are used for different purposes (e.g., project portfolio, course portfolio, longitudinal or growth portfolio, showcase portfolio). A full scale working model used to test and improve a design concept by making actual observations and necessary adjustments. The set of output values of a function.

9 Revolve Round Scale Model Solid Solid Modeling Subassembly Working Drawings Creating a 3D solid or surface by revolving a 2D shape about an axis. A rounded exterior blend between two surfaces. An enlarged or reduced representation of an object that is usually intended for study purposes. A three dimensional body or geometric figure. A type of 3D CAD modeling that represents the volume of an object, not just its lines and surfaces. An assembled part that is a part of a larger assembly. Drawings that convey all of the information needed to manufacture and assemble a design. Section 4.1 A. puzzle part B. graphical modeling C. mathematical modeling D. software modeling intro E. ^^cont. F. puzzle model creation on CAD Section 4.2 Assembly constraints Section 4.3 Portfolios Section 4.4 Creating drawings on CAD UNIT 5: Geometry of a design Key Term Acute Triangle Centroid Definition A triangle that contains only angles that are less than 90 degrees. A 3D point defining the geometric center of a solid.

10 Center of gravity Circumscribe Density Ellipse Fillet Inscribe Mass The measure of mass density is a measure of mascircums per volume. A shape generated by a point moving in a plane so that the sum of its distances from two other points (the foci) is constant and equal to the major axis A curve formed at the interior intersection between two or more surfaces. To draw a figure within another so that their boundaries touch but do not intersect. The amount of matter in an object or the quantity of the inertia of the object. Obtuse Triangle A triangle with one angle that is greater than 90 degrees. Parallelogram Polygon Principal Axes Quadrilateral Surface Area Tangent A four sided polygon with both pairs of opposite sides parallel. Any plane figure bounded by straight lines. The lines of intersection created from three mutually perpendicular planes, with the three planes point of intersection at the centroid of the part. A four sided polygon. The squared dimensions of the exterior surface A straight or curved line that intersects a circle or arc at one point only. I. Section 5.1 calculating properties shapes II. Section 5.2 A. geometric constraints

11 B. Intro to CAD modeling skills III. Section 5.3 determining density IV. Section 5.4 calculating properties solids V. Section 5.5 CAD model features VI. Section 5.6 physical property analysis

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13 Unit 6 Key Terms Key Term Definition

14 Aesthetic Asymmetry Balance Color Contrast Element Emphasis Form Graphic Design 1. Concerned with beauty or the appreciation of beauty. 2. Of pleasing appearance. Symmetry in which both halves of a composition are not identical. Also referred to as informal balance. A condition in which different elements are equal or in the correct proportions. There are three types of visual balance: symmetry, asymmetry, and radial. The property possessed by an object of producing different sensations on the eye as a result of the way it reflects or emits light. The state of being noticeably different from something else when put or considered together. A basic constituent part. Special importance, value, or prominence given to something. 1. Having the three dimensions of length, width, and depth. Also referred to as a solid. 2. The organization, placement, or relationship of basic elements, as volumes or voids in a sculpture, so as to produce a coherent image. The art of combining text and pictures in advertisements, magazines, books, etc. Harmony 1. The quality of forming a pleasing and consistent whole. 2. Agreement or concord. Pattern Principle A repeated decorative design. The method of formation, operation, or procedure exhibited in a given instance. Proportion 1. The relationship of one thing to another in size, amount, etc. 2. Size or weight relationships among structures or among elements in a single structure. Radial Symmetry Rhythm Shape Symmetry about a central axis. A regularly recurring sequence of events or actions. The two dimensional contour that characterizes an object or area,

15 in contrast to three dimensional form. Space Symmetry Texture Unity 1. The dimensions of height, depth, and width within which all things exist and move. 2. A free or unoccupied area or expanse. The correspondence in size, shape, and relative position of parts on opposite sides of a median line or about a central axis. Also referred to as formal balance. The feel, appearance, or consistency of a surface, substance, or fabric. The state of being united or forming a whole. Value The lightness or darkness of a color in relation to a scale ranging from white to black. Elements of Design LINE Line can be considered in two ways. The linear marks made with a pen or brush or the edge created when two shapes meet. SHAPE A shape is a self contained defined area of geometric or organic form. A positive shape in a painting automatically creates a negative shape. DIRECTION All lines have direction - Horizontal, Vertical or Oblique. Horizontal suggests calmness, stability and tranquillity. Vertical gives a feeling of balance, formality and alertness. Oblique suggests movement and action see notes on direction SIZE Size is simply the relationship of the area occupied by one shape to that of another. TEXTURE Texture is the surface quality of a shape - rough, smooth, soft hard glossy etc. Texture can be physical (tactile) or visual. COLOR Also called Hue VALUE Value is the lightness or darkness of a color. Value is also called Tone Principles of Design

16 BALANCE Balance in design is similar to balance in physics A large shape close to the center can be balanced by a small shape close to the edge. A large light toned shape will be balanced by a small dark toned shape (the darker the shape the heavier it appears to be) GRADATION Gradation of size and direction produce linear perspective. Gradation of of color from warm to cool and tone from dark to light produce aerial perspective. Gradation can add interest and movement to a shape. A gradation from dark to light will cause the eye to move along a shape. REPETITION Repetition with variation is interesting, without variation repetition can become monotonous. The five squares above are all the same. They can be taken in and understood with a single glance.

17 When variation is introduced, the five squares, although similar, are much more interesting to look at. They can no longer be absorbed properly with a single glance. The individual character of each square needs to be considered. If you wish to create interest, any repeating element should include a degree of variation. CONTRAST Contrast is the juxtaposition of opposing elements eg. opposite colours on the colour wheel - red / green, blue / orange etc. Contrast in tone or value - light / dark. Contrast in direction - horizontal / vertical. The major contrast in a painting should be located at the center of interest. Too much contrast scattered throughout a painting can destroy unity and make a work difficult to look at. Unless a feeling of chaos and confusion are what you are seeking, it is a good idea to carefully consider where to place your areas of maximum contrast. HARMONY Harmony in painting is the visually satisfying effect of combining similar, related elements. eg.adjacent colours on the colour wheel, similar shapes etc. DOMINANCE Dominance gives a painting interest, counteracting confusion and monotony. Dominance can be applied to one or more of the elements to give emphasis. (proximity)

18 UNITY Relating the design elements to the the idea being expressed in a painting reinforces the principle of unity.eg. a painting with an active aggressive subject would work better with a dominant oblique direction, course, rough texture, angular lines etc. whereas a quiet passive subject would benefit from horizontal lines, soft texture and less tonal contrast. Unity in a painting also refers to the visual linking of various elements of the work. Reverse Engineering Process

19 13 Reasons for Reverse Engineering 1. The original manufacturer of a product no longer produces a product 2. There is inadequate documentation of the original design 3. The original manufacturer no longer exists, but a customer needs the product 4. The original design documentation has been lost or never existed 5. Some bad features of a product need to be designed out. For example, excessive wear might indicate where a product should be improved 6. To strengthen the good features of a product based on long term usage of the product 7. To analyze the good and bad features of competitors' product 8. To explore new avenues to improve product performance and features 9. To gain competitive benchmarking methods to understand competitor's products and develop better products 10. The original CAD model is not sufficient to support modifications or current manufacturing methods 11. The original supplier is unable or unwilling to provide additional parts 12. The original equipment manufacturers are either unwilling or unable to supply replacement parts, or demand inflated costs for sole source parts 13. To update obsolete materials or antiquated manufacturing processes with more current, less expensive technologies Unit 7 Key Terms Key Term Allowance Auxiliary View Chain Dimensioning Clearance Fit Countersink Definition The tightest possible fit between two mating parts. A view that is used to show features that are located on an inclined surface in true size and shape. Also known as point to point dimensioning where dimensions are established from one point to the next. (as opposed to a datum dimension) Limits the size of mating parts so that a clearance always results when mating parts are assembled. A conical shaped recess around a hole, often used to receive a tapered screw.

20 Cutting Plane Line Decision Matrix Detail Drawing Detail View Dual Dimensions Fillet Full Section Half Section General Notes Interference Interference Fit Location Dimension Market Research Part Drawing Parts List Reference Dimension Section Lines Section View A line drawn on a view where a cut was made in order to define the location of the imaginary section plane. A tool used to compare design solutions against one another, using specific criteria. A dimensioned, working drawing of a single part. Also referred to as part drawing. A view that is used to show a magnified view of features that are too small to adequately specify in another view. Where alternate units are displayed within the same dimension. An inside radius between two intersecting planes. A sectional drawing based on a cutting plane line that extends completely through an object. A sectional drawing based on a cutting plane line that cuts through one quarter of an object. A half section reveals half of the interior and half of the exterior. Notes placed separate from the views; relate to the entire drawing. The amount of overlap that one part has with another when assembled. Limits the size of mating parts so that an interference always results when mating parts are assembled. A location dimension that defines the relationship of features of an object. The activity of gathering information about consumers needs and preferences. A drawing that contains all the information for making one part of the design. A list of materials or parts specified for a project. Also referred to as a bill of materials or BOM. A dimension, usually without a tolerance, used for information purposes only. A reference is a repeat of a given dimension or established from other values shown on a drawing. Reference dimensions are enclosed in ( ) on the drawing. Thin lines used in a section view to indicate where the cutting plane line has cut through material. A view that is used to show details not apparent on the exterior of the part.

21 Size Dimension Specified Dimension Taper Tolerance Working Drawings Placed directly on a feature to identify a specific size or may be connected to a feature in the form of a note. The dimension noted or, in the case of a tolerance, the part of the dimension from which the limits are calculated. Gradual diminution of width or thickness in an elongated object. The acceptable amount of dimensional variation that will still allow an object to function correctly.. Drawings that convey all of the information needed to manufacture and assemble a design. Section View Auxiliary View Chain Dimensioning