Descriptionary

current electricity; a flow of electrons through a conductive medium.

diode a device that permits electrons to pass in only one direction.

doping adding an impurity, such as phosphorus, to semiconducting silicon, to alter its conducting properties.

electrode any of the elements in a transistor that emits or controls the movement of electrons.

electron a subatomic particle with a negative charge.

farad a unit of capacitance.

germanium a semiconducting material used in mak­ing electronic components.

ground a large, conducting body, such as the earth, to which an electrical circuit is connected to prevent cables from picking up noise or emitting radio fre­quency interference.

henry the unit of inductance in which the variation of current at 1 ampere per second induces an electro­motive force of 1 volt.

hole

an area where no electron is present on the crystal of a P-type semiconductor; it acts as a positive charge.

impedance a measure of the opposition to the flow of current in an alternating-current circuit.

inductance the measure of a magnetic field gener­ated by current passing through an inductor.

inductor a wire coil that stores energy in the form of a magnetic field.

insulator any material through which electricity cannot flow. Opposite of a conductor.

integrated circuit a conglomeration of transistors and other electronic components on a silicon wafer.

junction on a transistor or a diode, the area where opposite types of semiconductor elements meet.

LED an acronym for light-emitting diode, as used in lighted calculator displays.

MEMS microelectromechanical system; micro­scopic gears, springs, mirrors, sensors, or other devices mounted on chips only millimeters wide. MEMS are used to sense motion, light, temperature, chemicals, and so on in everything from toys to pacemakers.

N-type a region of a semiconductor that has been treated (doped) with an impurity to create free nega­tive charges.

ohm

a measurement of electrical resistance, equal to the resistance of a conductor carrying 1 ampere of current at a potential difference of 1 volt between the terminals.

P-type a region of a semiconductor that has been treated with an impurity to create holes (an absence of electrons), which act as positive charges.

resistance a measure of how difficult it is for elec­tricity to flow through a component, measured in ohms.

resistor a device used to introduce resistance into an electrical circuit.

semiconductor any element that is both a poor con­ductor and a poor insulator, such as silicon.

series two or more components connected end to end so that the same current flows through each com­ponent.

silicon the most widely used semiconductor mate­rial; it goes into the manufacture of transistors, diodes, integrated circuits, and other components.

solid-state of electronic components, with no mov­ing parts.

transistor a miniature electronic component that controls and amplifies electric current; it is composed of a layer of semiconducting material sandwiched between two opposing layers of semiconducting mate­rial.

vacuum tube a glass tube from which all air has

been removed and containing electrodes between which current may be passed.

volt a unit of electromotive force.

watt a unit of power.

ROBOTICS

(Also see computers)

actuator a servo mechanism.

AGV automated guided vehicle.

algorithm a series of programmable steps used to solve a mathematically based problem.

android a robot having a humanlike form, as distin­guished from a boxlike robot or an industrial robot arm.

armed robotic vehicle

an unmanned, robotically- controlled vehicle armed with missiles and a gun tur­ret, currently under development with the military abbreviated as ARV.

automation a mechanical system that automatically controls its own tasks.

automaton robot.

bionics artificial organs or other human parts designed to replace real parts.

bugs errors in software.

Cartesian coordinates a system that defines an object's position; that is, an X coordinate (left to right) along one dimension, a Y coordinate (front to back) along another, and a Z coordinate indicating up and down. A robot arm may be capable of moving along these coordinates.

CIAM computerized, integrated, and automated manufacturing.

cybernetics the science of communication and con­trol as they apply to complex machines and living organisms.

cyborg in science fiction, a human equipped with bionic parts.

degrees of freedom the distance or amount a robot arm is capable of moving along any dimension, for example, up, down, left, right, cylindrically.

drive system the power plant and components that enable a robot to move.