Principles of Engineering
Glossary
ABET, Inc.: Accreditation Board for
Engineering and Technology Standards.
Abrading: The process of removing material
by applying friction
Abutment: The part of a structure (as an arch
or a bridge) that directly receives thrust or
pressure.
Acceleration: Exists when the velocity of a
particle changes with time.
Acceptance level: The maximum number of
defects in a sample that will permit acceptance
of the entire lot.
Accumulator: A device (as in a hydraulic
system) in which a fluid is collected and
especially in which it is kept under pressure as
a means of storing energy.
Accuracy: Degree of conformity of a measure
to a standard value.
Acoustical: Of or relating to the sense or
organs of hearing, to sound, or to the science
of sounds.
Actuator: A device that transfers fluid or
electrical energy into mechanical
energy.Adhesion: The process of fastening two
parts by the application of a third material such
as glue, epoxy, etc.
Allowable Stress: Level of stress judged to be
permissible in a design.
Alloy: A substance composed of two or more
metals or of a metal and a nonmetal intimately
united usually by being fused together and
dissolving in each other when molten.
Alternator: An electric generator for producing
alternating current
Analog: Of, relating to, or being a mechanism
in which data is represented by continuously
variable physical quantities
Angle: The union of two co-planar rays
intersecting at a common endpoint.
Annealing: The process of softening metal for
improved machinability or cold working by
heating it to its critical temperature, holding it
there until the temperature is uniform, then
cooling it slowly at a controlled rate.
Arch Bridge: a bridge that uses long span
arches for support”
Assembly: Consisting of individual parts fitted
together to create a final product
ASTM: American Society for Testing and
Materials
Attribute Listing: idea generation listing and
combining the attributes associated with a
situation.
Austenite: a solid solution in iron of carbon
and sometimes other solutes that occurs as a
constituent of steel under certain conditions
Automation: A machine or system that
operates with minimal human control: using
automated machines as control for production.
Axial Force: Force aligned along the central
axis of a material.
Bar Chart: A graph in which the data is
represented by horizontal or vertical bars.
Beam Bridge: A bridge whose main structural
element consists of a beam set across two or
more vertical supporting members.
Bearings: Devices used to reduce friction
between rotating shafts and fixed carriers.
Examples are roller, ball, and air bearings.
Belt: A continuous band that transmits motion
from one pulley to another.
Benchmark: A point of reference for making
measurements or judgments.
Bernoulli’s Law: A change in the velocity of a
fluid caused by a constriction produces an
opposite change in pressure.
Blow Molding: Method of fabrication in which
a warm plastic parison (hollow tube) is placed
between the two halves of a mold cavity and
forced to assume the shape of that mold cavity
by use of air pressure.
Bonding: Adhering materials with cement or
glue
directly to the tower, rather than hanging from
a larger cable running between the towers.
Boyle’s Law: The volume of a gas at a
constant temperature is inversely proportional
to its pressure.
Calendaring: The process of forming plastic
sheets by squeezing a thermoplastic material
between a series of rollers.
Caliper: any of various measuring instruments
having two usually adjustable arms, legs, or
jaws used especially to measure diameter or
thickness -- usually used in plural <a pair of
calipers> (0) see example of dial caliper below.
Brainstorming: A group problem-solving
technique that involves the spontaneous
contribution of ideas from all members of the
group; during this process, ideas are shared
but not critiqued.
Brazing: Sometimes called hard
soldering. Joining pieces of metal together
below the point of fusion by melting a third
British Thermal Unit (BTU): The US
Customary unit of thermal energy; the amount
of energy needed to raise the temperature of
one pound of pure water by one degree
Fahrenheit.
Brittleness: The description for a material
which is neither ductile nor malleable and will
fail suddenly without warning.
Broaching: a precision machining process
used to change the shape of a hole into
another shape (e.g. a square or keyhole); a
broach is used to do this (see pictures below)
Bronze Age: The period of ancient human
culture characterized by the use of bronze that
began between 4000 and 3000 B.C. and
ended with the advent of the Iron Age.
Buckling: Failure caused by bending, giving
way, or crumpling due to excessive force
CAD: computer-aided design; drafting or solid
modeling performed on a computer.
Cadmium Sulfide Cell: A light sensitive
resistor; also known as a photocell.
CAM: computer-aided manufacturing; aiding in
the manufacturing process through the use of
computer technology.
Cp: Capability Index, a measure of how
capable a machine or process is to stay within
the limits given for that process or machine.
Cable-stayed Bridge: A bridge in which the
deck is supported on either side of a central
tower or towers by cables. Unlike a suspension
bridge, the cables that hold the deck attach
Calorie: A metric unit of thermal energy; the
amount of energy needed to raise the
temperature of one gram of pure water by one
degree Celsius; A Calorie (capital C) is a “food
calorie” and is 1000 calories); 1.00 calorie =
4.186 Joule.
Cam: A mechanical device used to change
simple rotary motion into a more complex
motion.
Cam Cycle: one complete 360º rotation of a
cam
Carbide: A compound of carbon with one or
more metallic elements.
Carbon: A nonmetallic chiefly tetravalent
element found native (as in the diamond and
graphite) or as a constituent of coal, petroleum,
and asphalt, of limestone and other carbonates
, and of organic compounds or obtained
artificially in varying degrees of purity
especially as carbon black, lampblack,
activated carbon, charcoal, and coke
(Webster.com)
Carburizing: (Cementation) Adding carbon to
the surface of iron-base alloys by absorption
through heating the metal at a temperature
below its melting point in contact with
carbonaceous solids, liquids, or gasses.The
oldest method of case hardening.
Case Hardening: Carburizing and
subsequently hardening by suitable heattreatment all or part of the surface portions of a
piece of iron-base alloy.
Case study: A broad-based analysis of an
engineering problem.
Casting: The process of producing an object
by pouring a heated liquid material into a mold
and allowing it to solidify by cooling.
Catapult: A system used to launch objects.
(Ancient catapults used bent wood as the
power source, modern systems use power
such as steam.)
Cell: A single space for an entry in a spread
sheet
Center of Gravity: The point at which the
entire weight of a body may be considered as
concentrated so that if supported at this point
the body would remain in equilibrium in any
position. Same location as center of mass.
Chemical: Of, relating to, used in, or produced
by chemistry.
Chemical energy: The energy associated with
chemical bonds and bonding structure. This
includes the energy associated with changes in
phase from solid to liquid to gas. Chemical
energy does not lend itself to an equation.
Rather, there are tabulated values associated
with all known elements and compounds, as
well as values for the most common chemical
reactions.
Center of Mass: The point in a body or system
of bodies at which the whole mass may be
considered as concentrated. Same location as
center of gravity.
Chronological: Arranged in or according to
the order of time.
Centi: a prefix meaning one hundredth or
1/100 or 102; symbol: c
Class of Fit: Fits are arranged in three general
groups known as running and sliding fits,
locational fits, and force fits
Centroid: A point whose coordinates are the
averages of the corresponding coordinates of a
given set of points and which for a given plane
or three-dimensional figure (as a triangle or
sphere) corresponds to the center of mass of
a thin plate of uniform thickness and
consistency or a body of uniform consistency
having the same boundary.
Cementite: A compound of iron and carbon
known as “Iron Carbide,” which has the
approximate chemical formula Fe3C containing
6.69% of carbon. Hard and brittle, it is the hard
constituents of cast iron, and the normal form
in which carbon is present in steel. It is
magnetizable, but not as readily as ferrite.
Center Line: A line consisting of a long dash
followed by a short dash, that is used to show
and locate centers of arcs and circles, and to
describe the center axis of cylindrical forms.
Ceramic: A compound of metallic and
nonmetallic elements, for which the interatomic
bonding is predominantly ionic.
Chain: A continuous band consisting of metal
or plastic links that transmits motion from one
sprocket to another.
Charles’ Law: The volume of a gas at a
constant pressure is directly proportional to its
temperature.
Chart: A sheet or map giving information in the
form of a table, list or diagram
Circle: A closed curve with coplanar points at
the same distance from the center point.
Closed loop: The output of a process is
constantly monitored and the input adjusted
according to feedback provided by sensors.
Cohesion: The process of fusing two like
materials for the purpose of fastening.
Examples include friction welding, spot
welding, electron beam welding and laser
welding).
Cold forming: The process of working metal
into shape below the temperature of
recrystallization. Cold forming improves the
strength; machinability, dimensional stability,
and surface finish of metals.
Communication: The act of transmitting
useful data or ideas to one or more receivers;
can be one-way or two-way.
Component: A single device or part in an
assembly
Component Relational Sketch: A pictogram
showing the relationship of how the
components react together in a system.
Composite: A multiphase material formed
from a combination of materials that differ in
composition or form, remain bonded together,
and retain their identities and properties.
Compound: A substance of two or more
elements in fixed proportions. Compounds can
be decomposed into their constituent elements.
Compression: The effect of a force which
tends to shorten an object in the direction of
the force. Such a force is called a compressive
force, and the object it acts on is said to be in
compression. For example, the towers of a
suspension bridge are in compression.
Compression molding: A forming process in
which a powdered thermosetting plastic is
placed in a heated mold cavity then
compressed by a ram. After being
compressed, the plastic solidifies, the ram
retracts, and the part is ejected.
Compressor: A device that converts
mechanical force into pneumatic energy.
Computer aided drafting (CAD): The use of a
computer to create drawings
Computer Numeric Control (CNC): A
combination of a computer, a digital control
system, and a machine tool that enables the
machine to accept standard codes and
automatically make parts.
Concurrent: Occurring at the same time;
running parallel; acting in conjunction.
Conditioning: The process of treating a
material to achieve physical, electrical, or
mechanical properties.
Conduction: (Thermal definition) The transfer
of heat energy by physical contact.
Conflict Of Interest: Moral dilemma from dual
responsibilities or loyalties.
Contour: An outline, especially of something
curved or irregular.
Counter bore: A larger drilled hole concentric
with a smaller diameter hole. The larger hole is
not as deep as the smaller hole.
Countersink: A beveled or conical surface at
the top of a drilled hole for the purpose of
accepting a bolt head.
Coupling: A system used to connect and
transfer energy from one part to another usually shafts that rotate.
Crankshaft: A shaft that has journals which
changes reciprocating motion to rotary motion.
Creep: The slow change of dimensions of an
object from prolonged exposure to high
temperature or stress.
Critical Component: A component in a
system that, if it fails, renders the entire system
useless. In reliability studies, Critical
Components are the focus of improvement
efforts.
Critical temperature (points): Temperatures
at which internal changes or transformations
take place within a metal either on a rising or
falling temperature.
Crystalline: In some resins a state of
molecular structure denoted by uniformity and
compactness of the molecular chains. This
characteristic is attributable to the existence of
solid crystals with definite geometric form.
Current: The total amount of electrons flowing
through a circuit per unit time; measured in
Amperes (one coulomb of electrons passing a
single point per second).
Contribution: To supply a significant part.
Data: Information (measurements or statistics)
used as a basis for reasoning, discussion,
calculation or transmission.
Control Limits: (Lower and upper control
limits (LCL and UCL)); these describe what the
process is actually giving you; they are random
variables that are a function of the process
itself; they are observed or calculated, not set.
Data base: 1) Collection of similar information
in a computer file; a data base can be divided
into records and fields; 2) A facility which is a
central point for the collection and
dissemination of various types of information.
Convection: The transfer of heat energy by
moving a heated substance from one place to
another.
Deflection: A measure of deformation of a
structure due to applied loads.
Constraints: Restrictions or guidelines.
Conveyer: A belt like device used to move
objects.
Coplanar: Occurring in the same plane.
Deformation: Change in size and/or shape of
a body due to stress.
Delphi Technique: Individuals contribute
solution ideas independently to a central office.
Delta: Greek letter used in mathematical
formulae to represent change.
Density: Mass per unit volume.
Design: Translation of a concept into a
satisfactory, producible, salable form.
Design brief: A format for stating a design
problem.
Design Constraints: Requirements and
limitations under which the design process
takes place.
Desktop Publishing: Creating and publishing
a document using a PC and output device such
as a laser printer.
Destructive Testing: Material or product
testing in which information is learned about
the material/product via careful measurements
and recordings as the material/product is
destroyed.
Detail: Shape or feature on a model.
Deviation: The difference between the actual
measurements of a product and the design
specifications.
Diagonal: A line that is slanting or oblique
Dial Indicator: A precision measurement
device accurate to at least one thousandths of
an inch used to measure inside and outside
dimensions and depths of materials with the
output being read using a dial.
Diaphragm: Part of a pump that consists of a
flexible membrane.
Digital: An information system whose signals
have only two states, 1 (closed) or 0 (open).
Dilemma: A choice between equally
unpleasant courses of action.
Dimension Line: Thin line segment capped on
the ends with arrowheads, that indicate the
length of the dimension.
Dimension: Numerical value used on a
drawing to describe location, size, shape, or
geometric characteristic.
Dimensioning: The process of placing
measurements and notes on a drawing to
completely communicate its meaning.
Dimensional: A measure in one direction;
specifically: one of three coordinates
determining a position in space or four
coordinates determining a position in space
and time.
Discipline: An area of study
Displacement Diagram: (Re: cams) A
drawing that represents the desired motion of
the cam. The length of the diagram is equal to
the circumference of the working circle. The
height of the diagram is equal to the radius of
the working circle. The length of the diagram is
divided into intervals representing degrees of
rotation of the cam, a common interval would
be 30 degrees. The smaller the interval, the
more accurate the cam profile:
Displacement: Movement of an object through
a distance.
Drilling: To bore or drive a hole in. A
machining process that produces a hole (0)
Ductility: Property of materials that will
undergo plastic deformation or elongation of
more than 5% before fracture.
Dwell: That segment of cam rotation that
causes the follower to remain stationary
Dynamics: The behavior of matter when in
motion; (physics) the study of why objects
move.
Eccentric: A device that rotates in an offcenter position on an axle or shaft.
Edge: The line where two surfaces or points
intersect.
Elastomers: Any of various elastic
substances; An amorphous, cross-linked high
polymer that will stretch rapidly under tension,
reaching high elongations (500 to 1000%)
Electron Discharge Machining (EDM): A
separating process that produces a spark
between an electrode and the work piece
causing an erosion action. This process can
only be used on electrically conductive
materials.
Elastic Modulus (Young’s Modulus or the
Modulus of Elasticity): The ratio of stress to
strain when deformation is totally elastic; also a
measure of the stiffness of a material.
Elastic Potential Energy: The energy that can
be stored in the compression or extension of
an elastic material (traditional springs
included). The equation for the energy stored
in a spring is SE= ½ kx2 where “k” is the
spring constant (or modulus of elasticity for a
solid ) and “x” is the distance of extension or
compression.
Electromagnet: A core of magnetic material
surrounded by a coil of wire through which an
electric current is passed to magnetize the
core.
Electromagnetic energy: The energy
associated with electricity, magnetism, and
electromagnetic waves.
Elastomer: A polymeric material that may
experience large and reversible elastic
deformations.
Electrical: Of, relating to, or operated by
electricity.
Electrode: A conducting element that emits or
collects electrons or ions or controls their
movement.
Electronic: The use of electronics to control a
system or machine.
Element: A substance that cannot be
decomposed into simpler substances by
chemical means.
Ellipse: The group or set of all points in the
same plane whose sum of distances from two
points (foci) is constant. An ellipse looks like a
squashed circle or a circle viewed at an angle.
Engineering: A course of study followed by a
professional career that involves complex
analysis, design, and development of solutions
to technical problems.
Engineering technology: A course of study
followed by a professional career that involves
testing, troubleshooting, servicing, and
maintenance of technical product sand
systems.
English system: (U.S. Customary System) A
measurement system in which the fundamental
units are the foot, slug, and second.
Environment: The ecological community that
one lives in
Equilibrium: A state of balance due to the
equal action of opposing forces in a structure.
Essence: The quality or nature of something
that identifies it or makes it what it is.
Ethics: a. a set of moral principles or values b.
a theory or system of moral values <the
present-day materialistic ethic> c. plural but
singular or plural in construction : the principles
of conduct governing an individual or a group
<professional ethics> d. a guiding philosophy.
Eye Contact: Visual contact with another
person's eyes
Experimentation: Developing a solution by
conducting experiments and gathering
information.
Extension Line: Thin lines used to establish
the extent of a dimension.
Extrusion: A forming process which uses
force to push material through a die to give it a
specific cross sectional shape.
Factor of Safety (FOS): The ratio of ultimate
or yield stress (depends on the material and
standards people use) to allowable stress.
Failure: A fracturing or otherwise not
performing due to stress or outside events.
Fall: (Re: cam) That segment of cam rotation
that causes the follower to move downward.
Fatigue: The failure or decay of mechanical
properties after repeated applications of stress.
Fatigue tests give information on the ability of a
material to resist the development of cracks
(which eventually bring about failure) as a
result of a large number of cycles.
Fastening: The joining of two or more parts or
materials through the application of mechanical
devices, adhesive materials or a cohesive
process.
Feature: Any physical portion of an object,
such as a hole or fillet.
Ferrite: any of several magnetic substances
that consist essentially of ferric oxide combined
with the oxides of one or more metals (as
manganese, nickel, or zinc), have high
magnetic permeability and high electrical
resistivity, and are used especially in electronic
devices.
Ferrous: Related to iron (derived from the
Latin ferrum); iron base alloys.
Free Fall: Where an object moves freely under
the influence of gravity
Freehand: Done without the use of tools or
drawing equipment.
Gage blocks: Accurately ground and polished
blocks of steel, measured to one millionth of an
inch, and used as standards for measurements
Gear: A wheel with teeth that will allow the
transfer of power when coupled to another
gear.
Filter: A component used to remove impurities
from air or liquids.
Gear trains: A set of gears used to transmit
power, change output direction, or change
speed or force.
Finishing: The final processes applied during
the production or a part. (examples include
coating, de-burring, blast finishing, coloring,
cleaning, etc.)
Gender Bias: A settled or prejudicial outlook
towards males or females.
Firing Angle: The angle in between the
horizontal and the initial velocity vector of a
projectile
Grains: Individual crystals in metals.
Flame Hardening: A process of hardening a
ferrous alloy by heating it above the
transformation range by means of a hightemperature flame, and then cooling as
required.
Fluid: The medium used to transfer power can
be a liquid or a gas.
Force: A push or pull exerted by one object on
another.
Forging: The working of a piece of metal into a
predetermined shape by applying pressure or
impact blows. Forging increases the strength of
a part by compressing and aligning the surface
to the shape of the die.
Fracture: The act or process of breaking or the
state of being broken.
Free Body Diagram: A sketch of an object
(body) of interest with all the surrounding
objects stripped away and all of the forces
acting on the object (body) shown.
Frequency distribution: The number of times
that a certain characteristic occurs and is
represented using a histogram.
Friction: A force that opposes the motion or
intended motion of a body in contact with
another body.
Fulcrum: The support structure around which
a lever rotates. See lever.
Generator: A device that converts mechanical
energy to electrical energy.
Grain size: Average diameter of grains in the
metal under consideration, or alternatively, the
number of grains per unit area.
Graph: A diagram illustrating, by use of points,
lines, line segments, or curves, the relationship
between variables.
Graphics: A graphic representation (as a
picture, map, or graph) used especially for
illustration.
Gravitational Potential energy: The energy
stored by an object’s position in a gravity
field. On or near the surface of the Earth, PE =
mgh where “m” is the object’s mass, “g” is the
Earth’s gravitation constant, and “h” is the
change in height the object undergoes or has
the “potential” of undergoing.
Gravity: A fundamental physical force between
any two objects in the universe; as applied to
the earth, the force that is responsible for the
weight of objects.
Ground Line: In a perspective drawing, the
plane where objects appear to rest.
Hardening: The process by which a piece of
metal is hardened by heating it to or above the
critical temperature then cooling it rapidly,
usually by quenching in an oil or water solution.
Hard Drive: A magnetic storage device used in
computer systems.
Hardness: The measure of a material's
resistance to deformation by surface
indentation or by abrasion.
Heat Capacity: thermal capacity, ratio of the
change in heat energy of a unit mass of a
substance to the change in temperature of the
substance
Heat Engine: Device that converts the energy
of heat into mechanical energy
Histogram: A bar graph that shows the
frequency of events occurring for a given
range.
Hopper: A storage or supply bin that is used in
a manufacturing system.
Horizon Line: In a perspective drawing, the
imaginary line at eye level used as a
construction line.
Horizontal: A line parallel to the horizon.
Hot forming: The process of working metal
into shape while either in a molten or plastic
state.
Hydraulic fluid: A liquid that is used in
hydraulic systems to transfer energy; usually
an oil-based substance
Hypothesis: An educated guess on the
predicted outcomes of a series of events
Hysteresis: Literally translated -Lagging
behind- When a magnetic field is created the
flux lags the increase or decrease of
magnetizing force. Hysteresis results from the
fact that the magnetic dipoles are not perfectly
aligned. With rapidly reversing alternating
current the Hysteresis can cause a
considerable loss of energy overcoming the
internal friction of the molecular dipoles.
Impending Motion: Motion that is on the
verge of occurring, but not yet present.
Impact Testing: Testing used to determine a
material’s ability to withstand impact loads
without fracturing.
Inclined plane: A flat sloping surface along
which an object can be pushed or pulled; a
plane surface that makes an oblique angle with
the plane of the horizon. One of six simple
machines.
Inclusion: A foreign or impurity phase in a
solid.
Induction hardening: A process of hardening
a ferrous alloy by heating it above the
transformation range by means of electrical
induction, and then cooling as required.
Industrial Age: Age characterized by the
advent of manufacturing machinery and the
movement of populations to cities from farms
Infiltration: (Thermal definition) A mechanism
of heat transfer in which cold (or hot) outside
air infiltrates a heated (or cooled) building,
displacing heated (or cooled) air. This requires
additional energy be expended to heat (cool)
the newly infiltrated air.
Information Age: Age characterized by the
rise of Internet communications
Initial Velocity: The velocity of an object at the
beginning of the object’s motion
Innovation: the introduction of something new;
a new idea, method, or device.
Injection molding: The process of forcing a
heated soft plastic into a mold cavity where it is
cooled and hardens.
Interactive: Mutual or reciprocal
communication between people and/or
systems.
Interpersonal Skills: Those skills which
enable an individual to work with others in a
pleasant and productive manner.
Interface: The interconnection between
components or systems.
I/O: Input Output
Iron Age: The period of human culture
characterized by the smelting of iron and its
use in industry beginning somewhat before
1000 B.C. in western Asia and Egypt.
Isometric: A drawing projected so that the
plane of projection of a three-dimensional
drawing forms equal angles (120 degrees) to
each of the three axes of the object.
Job Function: Actual duties performed
regardless of title.
K-value: A numeric expression of a material’s
ability to conduct heat energy on a unitthickness basis.
Key: A part used to transfer torque between a
shaft and a hub
Key Seat: A groove or channel cut in a shaft
for the key to fit in
Kilo: a prefix meaning a thousand or 1000 or
103; symbol: k
Kinetic Energy: The energy of an object due
to its mass and motion; calculated using the
objects mass, m, and velocity, v.
Knurling: The process of impressing a
diamond or straight line pattern on a material
for the purpose of improving the appearance or
providing a gripping surface.
Laser: Light Amplification by the Stimulated
Emission of Radiation. A device that produces
a concentrated beam of light
Law of Gravitation: Governs the mutual
attraction between bodies.
Where:
F=the mutual force of attraction between the
two particles
G=a universal constant called the constant of
gravitation
M1M2= the masses of the two particles
multiplied together
r=the distance between the centers of the
particles
LCL: Lower Control Limit (see definition for
control limits)
LSL: Lower Specification Limit (see definition
for specification limits)
Lathe: A machine tool in which the work
material is rotated around a fixed horizontal
axis and cut by a tool that is mounted on a
movable carriage.
Lever: A rigid piece that transmits and
modifies force or motion when forces are
applied at two points and it turns about a third;
specifically: a rigid bar used to exert a pressure
or sustain a weight at one point of its length by
the application of a force at a second and
turning at a third on a fulcrum.
Liability: Having a legal responsibility for the
failure of a product
Line: The path of an infinite series of points. A
line has length, but not width or thickness.
Line Graph: A diagram, or a visual
representation, using a broken line to show the
relationship between certain sets of numbers.
Line Segment: A portion of a line that is
defined by two points.
Line Weight: The width and darkness of a line.
Linkage: A mechanical system of related
moving parts or connections.
Load: A force applied to an object (e.g. “a 30
lb load”)
Lobe: The highest point of a cam surface
Longitudinal axis: In the Cartesian coordinate
system, this would be the “ X “ axis. Machine
tools are generally designed for three axes of
motion (X, Y, Z) and an axis of rotation.
Lot: A group of products shipped or received
which is supposed to have a uniform level of
quality throughout.
Lubrication: Providing a substance such as
grease to reduce friction between moving
objects.
Magnetic: Of or relating to a magnet or to
magnetism; a magnetic material is attracted to
magnets.
Magnetism: A force that exists around
magnets that attracts ferrous materials and is
used in motors and generators.
Malleability: The property of a material which
enables it to undergo considerable plastic
deformation under compression before
fracture.
Manual: An act or process done by humans.
Manual machining: Describes the operation
of a machine tool by a human operator. No
computer control is involved.
Manufacturing: The total process of design,
application, and production.
Martensite: A distinctive needle like structure
existing in steel as a transition stage in the
transformation of austenite. It is the hardest
constituent of steel of eutectoid composition. It
is produced by rapid cooling from quenching
temperature and is the chief constituent of
hardened carbon tool steels. Martensite is
magnetic.
Mass: The quantity of matter, which a material
contains.
Mass properties: Descriptive characteristics
of an object in a 3D model.
Matrix: A chart for systematic search of
possible combinations, considering several
systems’ variables at once.
Max: The largest number in a data set.
Maximum Height: In the parabolic curve a
projectile travels the greatest elevation the
particle obtains occurs at the horizontal
coordinate of the Range/2.
Mean: The arithmetic average of a sample of
measurements.
Mean Time Between Failure (MTBF): The
average time of operation before a device is
likely to fail. This is a statistical value based on
testing of representative samples of some
product.
Mechanical: A form of energy, which uses
motion to do work.
Mechanical Energy: The energy, which is
possessed by an object due to its motion or its
stored energy of position.
Mechanical fastener: A mechanical device
such as a nail, screw, bolt, and etc. that is used
to fasten two parts together.
Median: The middle value in a rank order data
sample. Half the values will be greater and half
the values will be less than the median.
Melting point: Temperature at which a
material changes between solid and liquid
states.
Memory: Ability of a circuit’s output to remain
at one state even after the input condition that
caused that state is removed.
Metal: An opaque lustrous elemental chemical
substance that is a good conductor of heat and
electricity and, when polished, a good reflector
of light; most elemental metals are malleable,
ductile, and are generally denser than the other
elemental substances; metals are structurally
distinguished from nonmetals by their atomic
bonding and electron availability; the electron
band structure of metals is characterized by a
partially filled valence band; the "free electrons"
lost from the outer shells of metallic atoms are
available to carry an electric current; the
defining property of a metal is that it is an
element with a positive thermal coefficient of
resistively, meaning the electrical resistively of
a metal continuously increases as temperature
increases.
Metric system: A measuring system in which
the fundamental units are the meter, kilogram
and second.
Micro: a prefix meaning a millionth or
1/1000000 or 10-6; symbol: , “mu”
Micrometer: A precision measuring
instrument, which uses a precision screw and a
graduated scale.
Microprocessor: A complex digital chip that
performs the computer functions of arithmetic,
logic, and supervision.
Milli: a prefix meaning a thousandth or 1/1000
or 103; symbol: m
Milling: A process of cutting or material
removal, which combines a rotating cutter and
a traversing worktable allowing for processes
such as slotting, facing and pocketing.
Min: The smallest value in a data set
Mock-up: A full-sized structural model built
accurately to scale chiefly for study, testing, or
display.
Mode: The number that occurs most often in a
data set.
Modeling: Representation of a problem or
system.
Modeling Process: The process of creating a
solid, mathematical, or other representation for
the purpose of conducting a test.
Modulus of Elasticity: The slope of the line in
the linear elastic region created by the stress
on the object divided by the strain
Moment: The tendency to rotate about a point
determined by the product of a force multiplied
by the distance from this force to this point
Moment of inertia: An indication of the
stiffness of a particular shape. The higher the
moment of inertia, the less the deflection.
Motor: A device used to convert electrical
energy to mechanical energy.
Necking: Reduction of the cross-sectional
area of a material in a localized area caused by
uniaxial tension.
Newton’s First Law: (The Law of Inertia) –
Objects at rest tend to stay at rest, and objects
in motion tend to stay in motion at a constant
speed in a straight line unless acted upon by
an unbalanced force.
Newton’s Second Law: The net force acting
on an object in a given direction is equal to the
mass of the object multiplied by the
acceleration of the object in the same direction
as the net force.
Newton’s Third Law: The force of one object
(object 1) acting on another object (object 2) is
equal in magnitude and opposite in direction to
the force of the second object acting upon the
first.
Nitride: A compound of nitrogen and a metal.
Non-Destructive Testing: Material or product
testing in which information is learned about
the material/product via careful measurements
and recordings without destroying the
material/product.
Normal distribution: A statistical curve that is
bell shaped and shows the frequency
distribution for measured data. 68% of data will
be 1 standard deviation from the mean,
95.5% of data will be 2 standard deviation
from the mean, and 99.7% will be 3 standard
deviation from the mean.
Normal Stress: Stress perpendicular to the
area within the material that is resisting the
stress.
Nominal Group Technique: Utilizes a single,
trained leader to coordinate individual input
ideas.
Non-Traditional: Unique, creative, outside the
norm.
Normalizing: A heat treatment applied to
steel. Involves heating above the critical range
followed by cooling in still air. Is performed to
refine the crystal structure and eliminate
internal stress.
Nuclear energy: Nuclear energy is the energy
associated with nuclear bonding of the nucleus
of an atom. (Nuclear energy is the energy, E,
represented in the famous equation
E=mc2. The mass in this equation is not the
mass of the nucleus. The mass of an atom’s
nucleus is actually less than the sum of the
mass of the individual protons and neutrons
within the nucleus. The difference between
these masses is known as the “mass defect,”
and is the “m” in the E=mc2. In addition, “c” is
the speed of light.)
Object: Something visible or tangible.
Object Line: Slightly lighter than a profile line,
used to add all details to a sketch.
Oblique: A form of pictorial sketch in which
two axes are at right angles to each other (one
vertical, one horizontal) and the depth axis is at
an oblique angle.
Offset method: A way of determining the yield
point on a stress-strain curve when it is not
visibly identifiable.
Ohm’s Law: The relationship of voltage,
current and resistance in a circuit I=V/R, V=IR,
R=V/I
Open loop: A control system where there is no
feedback circuitry.
Optical: Of or relating to the science of optics
or vision.
Optimization: Process of making a system or
design as functional or effective as possible.
Order of Views: The relationship between the
views in orthographic projection.
Organic: Designation of any chemical
compound containing carbon with the
exception of some of the simple compounds of
carbon, such as carbon dioxide, which are
frequently classified as inorganic.
Orthographic: Right angle projection. The
views of an object are drawn in perpendicular
planes to one another.
Outside Suppliers: Vendors who provide
products or services to a company.
Out-sourcing: The process where by a
company buys certain products,
subassemblies, or services from outside
vendors.
Oxide: Compound of oxygen with another
element.
Parallel: Multiple pathways in a circuit.
Particle: A body of negligible dimensions or
when the dimensions of a body are irrelevant
to the description of its motion. E.g. an airplane
wing vs. the flight from NY to LA.
Pascal’s Law: A law that states when a force
is exerted on a fluid, the fluid transfers this
force equally against the walls of the vessel.
Pattern: A regular or repeated design, form,
order, or arrangement. Duplicates one or more
components and arranges the resulting
occurrences in a circular or rectangular pattern.
Pearlite: Lamellar structure resembling mother
of pearl. A compound of iron and carbon
occurring in steel as a result of the
transformation of austenite into aggregations of
ferrite and iron carbide.
Performance: The manner in which a
mechanism or part behaves.
Period: (Re: cam) the time it takes for one
complete cycle of the follower motion.
Phase: A volume of material that contains no
discontinuity in either composition or crystal
structure.
Photo-resistor: A device that changes
resistance according to light intensity.
Plastics: Any of numerous organic synthetic or
processed materials that are mostly
thermoplastic or thermosetting polymers of
high molecular weight and that can be made
into objects.
Polymer: A high-molecular-weight organic
compound, natural or synthetic, whose
structure can be represented by a repeated
small unit (mer). These long molecular chains
consist of repeating chemical units held
together by covalent bonds formed by a
polymerization reaction.
Porosity: The quality or state of being porous;
the ratio of the volume of interstices of a
material to the volume of its mass.
Position control: A system that uses the
location of objects to control functions.
Posture: The position or bearing of the body
whether characteristic or assumed for a special
purpose.
Potential Energy: Stored energy;
(Gravitational potential energy is stored energy
due to elevated position of an object: PE =
mgh; Elastic potential energy is stored energy
in elastic materials: PE = ½ kx2).
Potentiometer: A variable resistor.
Power: Force over time. Measured in Ft Lbs
Newton Meters or Watts.
Pressure: The force generated when energy is
applied to a fluid; force per unit area.
Phototransistor: A semiconductor switch that
produces an output when light falls on it.
Problem solving method: Systematic efforts
associated with large-scale problems, projects,
or designs.
Physical: Having material existence:
perceptible especially through the senses and
subject to the laws of nature.
Process control: To monitor and control a
process so that the quality of the
output/product improves.
Pictograph: Where symbols represent data on
a graph.
Process: The action of going through several
steps to reach a desired goal.
Picture Plane: In a perspective drawing, it is
the plane of projection.
Processor: An electronic device that operates
on data.
Pie Chart: A chart that represents data in the
form of slices from a 3-D circle.
Product: The end result of a manufacturing
process or processes.
Pitch: A distance of uniform measure
determined at a point on one unit to the same
corresponding point on the next unit; used in
threads , springs, and other machine parts.
Probability: The system of mathematics that
assigns odds or the chances of an event
occurring given certain parameters.
Production: The act of manufacturing a part or
product.
Profile Line: In sketching, a dark heavy line
that outlines the object drawn.
Projection Plane: An imaginary plane in the
line of sight on which an image appears.
Proportion: Proportion is a Principle of
Design. Comparative relationship between
things with respect to size.
Programmable Logic Controller (PLC): A
microprocessor used for control engineering,
primarily to replace relay logic controllers.
Programming language: A set of instructions
used to operate a machine or processor to
perform a task.
Projectile Motion: The motion of objects
launched in space with negligible air
resistance.
Public Welfare: Common good of society
Pulley: A wheel-like simple machine used to
reduce input force, change the direction of
force applied, or to increase the input
distance.
Range: Indicates amount of variation that
exists in the machine process.
R-Value: A numeric expression of thermal
insulation. R-values are the reciprocals of Uvalues.
Racial Bias: A settled or prejudicial outlook
toward various races.
Radiation: (Thermal definition) Transfer of
heat by temporarily transforming the heat
(kinetic motion of an objects atoms or
molecules) into electromagnetic waves (in the
infrared part of the EM spectrum). These
waves then travel until absorbed by another
object and transferred back into
atomic/molecular kinetic energy, which is heat.
Ram: Random Access Memory.
Range: a) The horizontal distance traveled by
a projectile. b) The difference between the
largest and smallest piece of numerical data.
Qualitative: Of, relating to, or involving the
measurement of quality or kind without
extensive mathematical analysis
Ratchet: a mechanism that consists of a bar
or wheel having inclined teeth into which a
pawl drops so that motion can be imparted to
the wheel or bar, governed, or prevented and
that is used in a hand tool (as a wrench or
screwdriver) to allow effective motion in one
direction only.
Quality assurance: The use of quality control
techniques associated with a process.
Reaction: Reactions are passive forces that
are induced at the supports of a structure.
Pump: A device that converts mechanical
energy to fluid energy.
Quality control: The prevention of bad parts
by the use of statistical techniques
Quality: The degree of customer satisfaction
of a product with respect to its use.
Quantitative: Relating to, or expressible in
terms of quantity, typically displayed in a line
graph.
Quenching: In the heat-treating of metals, the
step of cooling metals rapidly in order to obtain
desired properties; most commonly
accomplished by immersing the metal in oil or
water. In the case of most copper base alloys,
quenching has no effect other than to hasten
cooling.
Receiver: A device that accepts signals from
the emitter and is used in control systems.
Reciprocating: Motion back and forth along a
linear path.
Rectification: The process of converting AC
into DC.
Redundant: An additional part or subsystem
that is added to a system to increase the
overall system reliability. Redundant
components serve their function in parallel; as
long as any one redundant component is
functional, the entire system still functions as
designed.
Relay: Electromechanical switch where
contacts are opened or closed by a control
circuit in order to switch a secondary circuit.
ROM: Read Only Memory.
Reliability: The probability of satisfactory
operation of the product in a given environment
over a specified time interval.
Rupture Strength: The stress at which a
material ruptures.
Research: Careful or diligent search; studious
inquiry or examination; especially :
investigation or experimentation aimed at the
discovery and interpretation of facts, revision of
accepted theories or laws in the light of new
facts, or practical application of such new or
revised theories or laws; the collecting of
information about a particular subject.
Rotation: Clockwise or counterclockwise spin
of an object about its own axis.
Sample: A portion of the product randomly
taken for testing so decisions can be made
about the whole.
Scale: A graduated series of numbers used for
measurement purposes.
Scale: The ability to change the proportions or
size of one part of the image in relationship to
the other.
Resilience: The tendency of a material to
return to its original shape after the removal of
a stress that has produced elastic strain.
Scalar Quantity: A quantity that can be
described by magnitude only; answers the
question “how much?” Examples: mass, time.
Resistance: The ratio of the potential
difference across an electrical component to
the current passing through it. It is thus a
measure of the component's opposition to the
flow of electric charge. In general, the
resistance of a metallic conductor increases
with temperature whereas the resistance of a
semiconductor decreases with temperature.
Screw: A simple machine that uses threads to
apply force; a spiral inclined plane surrounding
a center shaft.
Resistor: A component used for introducing
resistance into a circuit.
Seals: A device to prevent the passage or
return of gas, liquid or air into a pipe or
container, a tight and perfect closure.
Semiconductor: Materials whose electrical
conductivity can be precisely altered by
appropriate manufacturing processes.
Resume: A document which briefly
summarizes who you are; it contains your
education, work experience, accomplishments,
and other necessary personal information.
Separating: The process by which a material
is divided into two or more parts.
Rise: The segment of cam rotation that causes
the follower to move upward.
Shafts: Cylindrical rods that support pulleys,
gears, and sprockets to transmit torque.
Rivet: Mechanical fastener with a large head
used for joining two parts together through a
hole. The rivet is clinched by forming a second
head on the opposite side.
Shape: The physical geometry of a model.
Robotics: The specialized field of engineering
and computer science that deals with the
design and application of robots.
Shearing: The process of separating a
material by applying pressure from opposing
directions; the area of separation is parallel to
the force applied.
Role Model: A person whose behavior in a
particular role is imitated by others.
SI: (System International) see metric system.
Rolling: A process in which a heated or cold
material is passed between rollers, squeezing
it into various shapes and thickness. Some
applications include rods, bars, sheet, plates,
and foils.
Series: A circuit with only one pathway for
electrons.
Shear: Force that acts parallel to the surface of
the material.
Sigma: Greek letter that is associated with the
standard deviation in statistics and stress in
strengths of materials; 
Simple Machine: Any one of the mechanisms
which were once considered to be the basic
elements from which all machines were
composed. These include the lever, the wheel
and axle, the pulley, the inclined plane, the
wedge, and the screw.
Sketch: A freehand drawing of an idea, or
solution to a problem without concern for detail.
Slope: An incline or decline mathematically
calculated as the rise divided by the run.
Soldering: The joining of metal surfaces with a
different metal (solder) that melts at a
temperature below the red heat temperature of
iron.
Solenoid: An electromagnetic device that
converts electrical energy into linear motion.
Solid modeling: Three-dimensional CAD
representation used to describe, simulate, and
predict the behavior of objects.
Solution: A satisfactory or possibly
satisfactory answer to a problem.
Space Age: Relating to, or befitting the age of
space exploration.
Spatial Configuration: The relative
arrangement of parts or elements within threedimensional space.
Specification Limits: (Lower and upper
specification limits (LSL and USL)); these are
the actual limits that are usually set based on
customer needs.
Spinning: The procedure of making sheet
metal discs into hollow shapes by pressing the
metal against a rotating form (spinning chuck)
by a tool.
Spline: One of a series of keyways cut around
a shaft and mating hole, used to transfer power
from a shaft to a hub while allowing a sliding
action between the parts.
Specific Gravity: The ratio of the density of a
substance to the density of some substance
(as pure water) taken as a standard when both
densities are obtained by weighing in air.
Spread: The distribution of data within a
statistical sample.
Spreadsheet: Software packages designed to
simplify the manipulation and presentation of
numbers and text; spreadsheets allow the user
to change parameters of the calculation and
see the effect on all calculations; also, most
spreadsheets have powerful presentation
software, such as graphs, bar charts, etc.
Spring A mechanical device that stores
energy by expansion or contraction due to
pressure, force, or stress applied, that will
release energy and return to shape when the
force or stress is removed.
Sprocket: A circular mechanical device with
teeth that is used to impart motion to chains.
Standard deviation: A mathematical measure
of the spread in a data sample. Symbol: ,
“sigma”
Standards: Benchmarks used to measure or
combine results.
Statics: The study of objects in a state of
equilibrium.
Station Point: The point where the viewer
stands to observe the image on the picture
plane.
Statistics: 1) a branch of mathematics dealing
with the collection, analysis, interpolation, and
presentation of masses of numerical data; 2) a
collection of quantitative data.
Statistical Process Control: SPC is a method
of monitoring, controlling and, ideally,
improving a process through statistical
analysis. Its four basic steps include measuring
the process, eliminating variances in the
process to make it consistent, monitoring the
process, and improving the process to its best
target value.
Stereotyping: Something conforming to a
fixed or general pattern.
Stone Age: The first known period of
prehistoric human culture characterized by the
use of stone tools.
Strain: The elongation of a material under
stress divided by the material’s length prior to
stress; symbol: , “epsilon.”
Stress: A material’s internal resistance to
force; symbol: , “sigma”; calculated by
dividing the force in the material by the area of
the material that is subjected to the force:
Stress-Strain Curve: A graph of stress (on the
y-axis) versus strain (on the x-axis) for
materials under stress; enables engineers to
learn about the strength of material as it
deforms elastically and plastically.
Stud: Vertical Structural member.
Surface: A two-dimensional area on a plane.
Suspension Bridge: “a bridge having a road
or deck hung from a pair of steel cables, each
carried by two towers, one at each bank; e.g.,
the Golden Gate Bridge over San Francisco
Bay”
Switch: Device used to control the flow of
current in a circuit.
Synchronous: An AC electric motor whose
speed is dependent upon the frequency of the
input current.
Synetics: A group interaction, utilizing
seemingly unrelated ideas, to bring about one
or two solutions.
Synthesis: The process of forming, generating
or putting together ideas or parts to form a
whole.
Synthetic: Not naturally occurring,
manufactured.
Systematic: Marked by thoroughness and
regularity, also methodical in procedure or plan
Table: A table is made up of rows and
columns of cells that you can fill with text and
graphics. Tables are often used to organize
and present information.
Tank: A usually large receptacle for holding,
transporting, or storing liquids.
Tapping: The process of cutting an internal
thread using a tap.
Technical writing: Treating a document with
the goal of providing clear and concise
information, rather than entertainment or story
telling; a technical document/report
incorporates diagrams and multi-media
information to provide technical information.
Temple Stick: A temperature-sensing device
that looks like a crayon and only melts when
applied to the surface of a material heated to a
specific, predetermined temperature.
Temperature: A measurement of how warm
something is; also the average kinetic energy
of the individual molecules of a substance
Tempering: A heat treating process that
reduces the brittleness of a hardened piece of
steel by heating it to a point below the critical
temperature and cooling it at some rate.
Tension: A situation in which force is applied
to an object that stretches, expands or
lengthens the object.
Tensile: Of or relating to tension; a “tensile”
force is a force that serves to stretch, expand,
or lengthen an object.
Thermal: of, relating to, or caused by heat.
Thermal energy: Thermal energy is basically
kinetic energy. It is the sum of the individual
atoms’ kinetic energies. Even in a completely
motionless object, the atoms from which the
object is made are in constant motion and thus
have thermal energy.
Thermodynamics: The study of thermal
energy as it moves from one substance to
another.
Thermoplastic: A material capable of being
repeatedly softened by increases in
temperature and hardened by decreases in
temperature. Thermoplastics are those
materials whose change upon heating is
substantially physical rather than chemical.
They are largely one- or two-dimensional
molecular structures such as: nylons,
polycarbonates, acetals, polysulfones, and
vinyls.
Thermoset: A material, such as an epoxy or
polyester resin, which has the property of
undergoing a chemical reaction by the action of
heat, catalyst, ultraviolet light, etc., to become
a relatively insoluble and infusible substance.
They develop a well-bonded three-dimensional
structure upon curing. Once hardened or
cross-linked, they will decompose rather than
melt.
Theory: A plausible or scientifically acceptable
general principle or body of principles offered
to explain phenomena; (scientifically quite
different from a “hunch”)
Thread: A spiral groove cut into the outside of
a shaft or the inside of a hole used to hold
parts together.
Threading: The process of cutting spiral
mating surfaces for the purpose of providing
mechanical tension between two parts. (The
process of using a tap or die)
USL: Upper Specification Limit (see definition
for specification limits)
Time Line: A table listing important events for
successive years within a particular historical
period.
Valve: Any of numerous mechanical devices
by which the flow of liquid, gas, or loose
material in bulk may be started, stopped, or
regulated by a movable part that opens, shuts,
or partially obstructs one or more ports or
passageways.
Timetable: Estimated timeline for completion
of a process.
Tolerance: The difference between the
maximum and minimum dimensions allowed
within the design of a product.
Torque: A turning or twisting force that
produces or tends to produce rotation or
torsion
Torsion: The twisting or wrenching of a body
by the exertion of forces tending to turn one
end or part about a longitudinal axis while the
other is held fast or turned in the opposite
direction.
Toughness: The energy required to break a
material, which is equal to the area under the
stress-strain curve. The toughest materials are
those with very great elongations to break
accompanied by high tensile strengths such
materials nearly always have yield points.
Ultimate Strength: The maximum stress a
material withstands prior to necking.
Vanishing Point: The point on the horizon
where parallel objects appear to intersect due
to convergence.
Variation: Differences that exist in any
manufacturing process. Abnormal variations
need to be removed; random or normal
variations cannot be removed.
Vernier caliper: Instrument to precisely
measure inside and outside diameters.
Vernier Scale: A physical scale that is used on
a variety of measurement tools that allows the
user to measure to one ten thousandths of an
inch.
Traditional: Standard or established practice.
Vector Quantity: A quantity that must be
described by both magnitude and direction;
answers the questions “how much?” and
“which way?” Examples: velocity, Force.
Transducer: A device used to inform various
control systems.
Velocity: The ratio of the displacement of a
particle and the time interval
Transformation: A constitutional change in a
solid metal, e.g., the change from gamma to
alpha iron, or the formation of pearlite from
austenite.
Vertical axis: In the Cartesian coordinate
system, this would be the “Y“ axis. Machine
tools are generally designed for three axes of
motion (X,Y,Z) and an axis of rotation.
Transverse axis: In the Cartesian coordinate
system, this would be the “Z“ axis. Machine
tools are generally designed for the axis of
motion (X, Y, Z) and a axis of rotation.
Vertical: Perpendicular to the horizon.
Triple beam balance: Equipment to measure
mass using gravitational pull.
Views: The different viewing perspectives
found in mechanical drawing.
Turning: Using a lathe.
Visual Aids: Instructional devices (as a chart,
map, or model) that appeals chiefly to vision
use to convey difficult concepts.
U-Value: A numeric expression of a material’s
thermal conductivity; the degree that heat
energy can pass through a material.
UCL: Upper Control Limit (see definition for
control limits)
Viscosity: The thickness or flow characteristic
of a liquid; the more viscous, the slower a liquid
will flow.
Visualization: To form a mental image of
something.
Vita: A document which briefly summarizes
who you are; it contains your education, work
experience, accomplishments, and other
necessary personal information.
Voltage: The electromotive force in a circuit.
Volume: The amount of space occupied by a
three-dimensional object as measured in cubic
units.
Water jet: A separating process that uses a
high-velocity stream of water as the cutting
agent. (abrasive material is sometimes used in
the water)
Watt’s Law: The mathematical relationship
expressing that power is the product of Voltage
and Current
Wedge: A simple machine used to change the
direction of applied force via its triangular
shape; used for splitting wood and rocks,
raising heavy bodies, or for tightening by being
driven into something.
Welding: The process of joining metal
together by heating to the fusion point
Weight: The gravitational pull (force) on an
object.
Wheel and Axle: a. A simple machine in which
a larger diameter wheel requires less force to
turn than a smaller diameter axle (e.g. valve
handles, steering wheel); b. A simple machine
that turns rotary motion into linear motion
whereby increasing the diameter of the wheel,
the linear distance traveled for one revolution
of the axle can be increased; c. a rotating lever
Whistle Blowing: Public disclosure of a moral
or ethical problem.
Work: Done by a force acting on an object
when the point of application of that force
moves through some distance and the force
has a component along the line of motion
Working Circle: A circle in a displacement
diagram that has a radius equal to the distance
from the center of the cam to the highest point
on the cam.
Working Relationship: A mutually satisfying
and productive ongoing interaction.
X-bar: Average or level at which a machine or
process is operating