backbone

The main line of a communications network that supports all the data being transmitted.

bandwidth

The amount of information or data that can be sent over a communications channel in a given period of time. The higher a channel's bandwidth, the more information it can carry.

bus topology

A network configuration in which all the nodes are connected to a common line with two endpoints. Bus topology is easy to connect and does not require a lot of cable.

CAT 5

A type of communications cable used for high rates of data transmission.

coaxial cable

A type of communications cable used in heavy industry. Coaxial cable has the highest resistance to noise of all copper cables.

compliant

A type of end effector that allows a robot to tolerate and compensate for misaligned parts. Robots can use either an active or passive strategy to achieve compliance.

controller

The main device that processes information and carries out instructions in a robot. Also known as the CPU or processor.

controller area network

An industrial network designed specifically for noisy environments. Also known as CAN.

DeviceNet

A protocol created by Allen-Bradley that operates on a controller area network (CAN) infrastructure.

dielectric material

The insulating non-metallic material that separates conductors and the outer protective covering.

distributive control

A method of control that divides remote I/Os and control devices among multiple controllers instead of using a single controller to control all the devices.

electrical noise

A power line disturbance caused by sudden changes in the load. Electrical noise is problematic to robot communications equipment because they cannot always differentiate between an intended electrical pulse and an unintended electrical spike.

electromagnetic interference

Electrical noise in a circuit that can interrupt or degrade the performance of the circuit. Fiber optic cables are resistant to electromagnetic interference.

Ethernet

The oldest computer network. Ethernet is considered the industry standard for local area networks.

fiber optic cable

A cable packed with thin, flexible glass or plastic optical fibers that transmit light instead of electricity.

fieldbus

A type of industrial network that uses distributive control instead of relying on a central controller.

Foundation Fieldbus

A fieldbus protocol created by a not-for-profit trade group. Foundation Fieldbus is designed to be compatible with other networks.

header

A data field within a packet that includes the IP addresses of the sender and the receiver.

industrial Ethernet

A version of Ethernet that uses cables that are made to withstand harsh industrial environments and with built in redundancies to greatly minimize interruptions in service.

industrial network

A means to provide constant communication between components of an automated system.

infrastructure

The physical equipment that makes up the network. The most important part of industrial network infrastructure is the transmission medium.

interfacing

The interaction between two or more devices or systems that handle data in different ways, such as in different codes or formats, to communicate with each other.

interlocked guard

A barrier with a tripping mechanism that causes the robot to stop when the guard is moved. An interlock is generally a switch that goes on a door or hinge and can be opened only with a key.

IP address

A unique numeric identifier for each node on a network. An IP address is comparable to the mailing address of your home.

jacket

The protective outer layer surrounding coaxial cable. The jacket protects the cable from physical damage.

message

The instructions contained in a data packet.

Modbus

A communication protocol created by Modicon to be compatible with a variety of other networks. Modbus uses an older type of interface called RS-232.

network integration

The ability to use or combine data from multiple sources while maintaining the integrity and reliability of the data.

packet

A unit of data that carries information such as instructions. TCP/IP is a communications protocol that breaks data up into packets.

PC

A personal computer. PCs are processor driven and are now used to do most robotic programming.

Profibus

A fieldbus protocol created by PI International. Profibus is widely used in industry.

protocol

The language spoken between robots, computers, and any other devices on a network to help them exchange information.

radio wave

A wave on the electromagnetic spectrum that is used for communication.

redundancies

Systems that send identical messages through different means to reduce the probability of errors in the transmission. A redundancy can also be a duplicate component to provide an alternative in case one component fails.

ring topology

A network topology that connects the nodes in a closed loop. Ring topologies are very orderly, with each device on the network performing an equal amount of work.

RS-232

An older type of communications cable used for connecting peripheral devices to a computer. The RS-232 is inexpensive and common to many systems, but has low bandwidth and a limited range.

sequential control

The ability to ensure that a connected series of events occur in a certain order. If a robot performed tasks out of order, it could lead to damaged equipment.

shield

An inner protective covering on a wire or cable.

shielded twisted pair

Shielded cable that is made of pairs of copper wires that are twisted around each other. Shielded twisted pair cable has more immunity to electrical noise than unshielded twisted pair cable.

star topology

A network topology in which each node on the network is connected to a central controller. In a star configuration, the controller takes an active role in analyzing and transmitting data packets while the nodes passively receive the information.

TCP/IP

A communications protocol used by Ethernet that breaks up data into small packets.

teach pendant

A hand-held device that can be used to program a robot and control its movements.

topology

The configuration of network cable and devices. Common topologies include bus, ring, and star.

transmission medium

The means by which data travels through a network. Typically this is some type of cable, although wireless networks are becoming increasingly common.

trunk

The common line of a bus network that supports all the data being transmitted.

twisted pair cable

Cable made of pairs of copper wires that are twisted around each other. Twisted pair is relatively inexpensive and can be found in most buildings.

unshielded twisted pair

Cable made of pairs of copper wires that are twisted around each other.

wireless network

A network that uses radio waves instead of copper or fiber optic cable. In a wireless network, a device transmits a radio signal through an antenna.

wireless router

A router that transmits data through an antenna rather than a network cable. Wireless routers use radio waves.