9th Grade - Intro to Engineering PLTW Test
parametric modeling
3D modeling where entities are constrained to, dependent on, or associated with other entities
3D model
a computer representation used to convey detailed information about a physical object
functional analysis
a description of what a product does, its inputs, and its outputs
generative design
a design process where a software runs algorithms to determine all the possible designs that meet the parameters and constraints
resistor
a device used to control the passage of an electric current in a circuit
focal point
a feature in a design that attracts the eye
normal distribution
a function that represents the distribution of variables as a symmetrical bell-shaped curve
histogram
a graph of vertical bars representing the frequency distribution of a set of data
schematic
a graphical model of a circuit
box-and-whisker plot
a graphical model of data for a single variable
concept sketch
a graphical representation of an idea that can quickly communicate design intent and details
system
a group of interacting, interrelated, or interdependent parts that function together as a whole to accomplish a goal
assembly
a group of parts that are connected and form one unit
object line
a heavy solid line used to represent the outline of an object
blind hole
a hole that does not pass completely through an object
through hole
a hole that passes completely through an object and maintains the same diameter the entire time
construction line
a lightly-drawn line used to guide drawing other lines and shapes
mock-up
a model or replica used for instructional or experimental purpose
automaton
a moving mechanical device that performs a repetitive function
invention
a new product, system, or process that has never existed before
circuit
a path for an electrical current to flow through conductors from an electrical energy source to at least one load that consumes energy
human-centered design
a problem-solving process that focuses on designing a product from the perspective of the people it will affect and that usually follows the steps of inspiration then ideation then implementation
cam
a rotating or sliding part in a mechanism used especially to transform rotational motion to linear motion or vice versa
additive modeling
a solid modeling technique where volume is added and built on to existing volume
subtractive modeling
a solid modeling technique where volume is removed from existing volume
orthographic view
a straight-on, "front" view that only has length and width
modularity
a strategy for managing complex systems by dividing system components into functional clusters to form separate sub-systems or modules
adhesive
a substance used for sticking objects or materials together
title block
a template that gives general information about a drawing
aesthetic
a term used to describe people's appreciation of beautiful things
decision matrix
a tool used to compare design solutions against one another using specific criteria
outlier
a value that is 1.5 interquartile ranges lower than the first quartile or higher than the third quartile
spring constant
a value that represents how stiff a spring is
isometric view
a view of a three-dimensional object from an 120 degree angle that shows all three dimensions equally
sectional view
a view that shows an object as if part of it were cut away to expose a cross-section
conceptual model
a visual representation of an idea
design brief
a written plan that identifies a problem and the criteria and constraints for the solution
wabi-sabi
an aesthetic style that embodies naturalness, simplicity, and subtle imperfection
innovation
an improvement of an existing technological product, system, or method
stakeholder
an individual or group who may affect or be affected by a decision, activity, or outcome of a project
tapering
becoming gradually narrower at one end
standards
clear descriptions of established technical criteria, methods, processes, and practices
satisficing
deciding that the best design decision is not the optimal design in a situation
Hierarchy of Needs
five user-centered goals that a design must satisfy in order to achieve optimal success: functionality, reliability, usability, proficiency, and creativity
precision
how close a group of measurements are to each other (highest value - lowest value)
accuracy
how close a measurement is to the target (average value - target value)
constraints
limitations or restrictions on a design process such as time, funding, space, and materials
sustainability
meeting the needs of the current generation without negatively affecting future generations
rotation
movement around an axis
translation
movement parallel to an axis
raw materials
natural resources used to make finished products
dowel pins
pieces used to permanently assemble parts that require precise alignment
value
relative lightness or darkness of a color
input
something put into a system
output
something that results from a system
criteria
specific, concise design requirements that describe what the design solution must do to meet the stakeholders' needs
product life cycle
stages that a product goes through in its life: development, introduction to the market, growth of market share, maturity, and decline
evaluate solution
step five of the design process
construct and test
step four of the design process
define problem
step one of the design process
present solution
step six of the design process
develop solution
step three of the design process
generate concepts
step two of the design process
factor of safety
the ability of a design to still perform successfully even if a variable was underestimated during its calculations
tolerance
the acceptable amount of dimensional variation that will still allow an object to function properly
traction
the adhesive friction of a body on a surface on which it moves
mean
the average value of a dataset
unity
the consistent use of design elements
strain
the deformation or displacement of a material that results from applied stress
voltage
the difference in electrical potential energy between two places in a circuit
materials
the elements, constituents, or substances of which something is composed or can be made
stress
the force applied to a material divided by the material's cross-sectional area
spring force
the force exerted by a spring, which always goes in the opposite direction as the applied force
friction
the force that resists motion between two surfaces
range
the highest value in a dataset minus the lowest value
80/20 Rule/Pareto Principle
the idea that approximately 80% of the effects of a large system are caused by only 20% of the variables in that system
uncertainty principle
the idea that measuring certain sensitive variables in a system can alter them and impact or interfere with the accuracy of the measurement
Occam's Razor/Law of Economy
the idea that the simplest solution is often the best
variability
the measure of consistency in a set of data
first quartile
the median of the lower half of the dataset, excluding the median
third quartile
the median of the upper half of the dataset, excluding the median
spatial visualization
the mental representation and manipulation of two- and three-dimensional objects
median
the middle value of a dataset
follower
the part whose movement results from the rotation of a cam
interface
the place at which parts meet and interact
mimicry
the process of copying properties of a familiar object, organism, or environment
prototyping
the process of creating a simple, sometimes incomplete model of a design
optimization
the process of making the best or most effective use of resources to get the best possible solution
iteration
the process of repeating earlier steps of the design process to get a satisfactory result
reverse engineering
the process of taking something apart and analyzing its workings in detail
efficiency
the ratio of desired output energy compared to input energy
proportion
the relationship between elements in a design with respective to size
complexity factor
the square root of the sum of the number of parts multiplied by the sum of the number of interfaces
kinematics
the study of motion of a system without consideration of forces acting within the system
Scaling Fallacy
the tendency to assume that a design that works on one scale will work at smaller and larger scales
iconic representation
the use of images to make concepts, actions, and objects easy to find, recognize, learn, and remember
economy
the use of the bare minimum elements
degree of freedom
the variable by which an object can move
interquartile range
third quartile minus first quartile
systems thinking
understanding a system by examining the web of relationships among the interacting parts or elements