PLTW (IED) Midterm Exam Study Guide

Orthographic Projection

A method of representing three-dimensional objects on a plane having only length and breadth. Also referred to as Right Angle Projection.

Brainstorm

a group technique for solving problems, generating ideas and stimulating creative thinking by unrestrained discussion.

Constraint

a limit to the design process.

Design

iterative decision making process that produces plans by which resources are converted into products or systems that meet human needs

Design Statements

part of a design breif that challenges to designer, describes what a design solution should do without describing how to solve the problem.

Engineering Notebook

book in which an engineer will formally document all of his/her work associated with a design.

Prototype

full-scale working model used to test a design concept by making actual observations and necessary adjustments.

Research

systematic study of materials and sources in order to establish facts and reach new conclusions.

Chemical Engineering

Applying chemistry, physics, and engineering to design an operation of plants for the production of materials that undergo chemical changes during the processing.

Civil and Construction Engineering

Plan, Design, and Supervise the construction of facilities

Electrical Engineering

Deals with the motion of electrons in the metals.

Mechanical Engineering

applies the principles of mechanics and energy to design machines and devices.

What is the order of the design process?

1. Define the problem

2. Generate Concepts

3. Develop a Solution

4. Construct and Test Prototype

5. Evaluate the Solution

6. Present Solution

Tonal Shading

the representation of light and shade on a sketch or map

Center Line

defines the center of arcs, circles, or a symmetrical parts

Extension Line

represents where a dimension starts and stops

Dimension Line

Represents distance

Object Line

heavy solid line used on a drawing to represent the outline of the object

Construction Line

lightly drawn lines to guide drawing other lines and shapes

Hidden Line

represents an edge that is not directly visible

What are the three spatial dimensions?

Length, Width and Height

Working Drawing

drawing that is used to show material, size, and shape of a product for manufacturing purposes.

Oblique Sketch

form of pictorial in which an object is represented as true width and height, but the depth can be any size and drawn at any angle.

Multi-View Drawing

drawing which contains views of an object projected onto two or more orthographic planes

Perspective Sketch

pictorial sketch in which vanishing points are used to provide the depth and distortion that is seen with the human eye.

Isometric Sketch

pictorial sketch in which all three drawing axes form equal angles of 120 degrees with the plane of projection.

Pictorial Sketch

shows an objects height, width, and depth in a single view

Cavilier Pictorial

olique pictorial where the height, width, and depth are represented at full scale.

Cabinet Pictorial

olique pictorial where the height and width are represented at full scale but the depth is represented at half scale

Leader Line

indicates the dimensions of arcs, circles, and detail

Accuracy

the degree of closeness of measurements to the actual or accepted value

Precision

how close together the data points are

Histogram

graph of vertical bars representing the frequency of distribution of a set of data

What does it mean when a sketch is over dimensioned?

the drawing has repeated dimensions of chain dimensions.

Why is the placement of a dimension so important?

As the designer, we do not want to confuse the interpreter of the drawing. By following the guidelines for dimensioning, the measurements will be in the same area on every drawing.

How can statistical and analyzed data be used to inform, justify, and validate a design or process?

Data from accuracy validates a process, or design to see how accurate a process is or how precise the product is.

Statistics

Collection of methods for planning experiments, obtaining data, organizing, summarizing, and presenting, analyzing, interpreting, and drawing conclusions based on data.

Mean

the arithmetic average of a distribution, obtained by adding the scores and then dividing by the number of scores

Median

the middle score in a distribution; half the scores are above it and half are below it

Mode

The value that occurs most frequently in a given data set.

Kinematics

The science of describing the motion of objects using words, diagrams, numbers, graphs, and equations

Displacement

Distance and direction of an object's change in position from the starting point.

Perspective Sketching

- Architects use perspective sketching

- Every perspective sketch has a vanishing point

and a horizon line

- there are no set angles in perspective sketches

Design Process - Step 1

Define the Problem.

- criteria and constraints

- design brief

Design Process - Step 2

Generate Concepts

- Brainstorm

- Decision Matrix

Design Process - Step 3

Develop a Solution

- Technical Drawings

Design Process - Step 4

Construct and Test Prototype

- Build and test a Prototype

Design Process - Step 5

Evaluate Solution

- Evaluate your solutions effectiveness

Design Brief

A written plan that identifies a problem to be solved, it's criteria, and it's constraints. The design brief is used to encourage thinking of all aspects of a problem before attempting a solution.

Geometric Constraints

Restrictions applied to geometric entities; for example, Coincident, Collinear, Concentric, Fixed, Parallel, Perpendicular, Horizontal, Vertical, Tangent, Smooth, Symmetric and Equal Constraints.

Assembly Constraints

parameters that define the geometric relationships between components in a CAD assembly (mate, flush, angle, tangent, insert)