Z94.12.3 C  - Manufacturing Automation & Computer Control

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CAD. Computer-Aided Design, using computers to aid in designing products. (See COMPUTER-AIDED DESIGN.)

CADAM. The Computer-Graphics Augmented Design and Manufacturing (CADAM) System is an interactive graphics system for computer-aided design and manufacturing. The system includes a design/drafting package, together with a number of aids to design analysis.

CALIBRATION. The adjustment of a device so that output is within a designated tolerance for specific input values.

CAPACITANCE. The property of a circuit or body that permits it to store an electrical charge equal to the accumulated charge divided by the voltage. The unit of capacitance is a farad.

CAPACITOR. An electric device consisting of conducting surfaces separated by thin layers of insulating material (a dielectric). It introduces capacitance into a circuit, stores electrical energy, blocks the flow of direct current, and permits the flow of alternating current to a certain degree. Also referred to as a condensor.

CAPP (COMPUTER-AIDED PROCESS PLANNING). A prototype software development that provides a data management framework designed to assist the functions of process planning in the manufacture of discrete parts. The system enables a process planner to automatically access standard process plan specification data in an interactive and dynamic manner.

CARD. An information-carrying medium that introduces instructions to computers, either directly or indirectly and often via punched codes.

CARRIER. (1) A particular wave which has constant amplitude and frequency, and a phase which can be modulated by changing amplitude, frequency, or phase. Also, an entity which has the ability to carry an electric charge through a solid. For example, holes and conduction electrons in semiconductors. (2) A continuous frequency capable of being modulated or impressed with a second (information carrying) signal.

CARTESIAN COORDINATE SYSTEM. A system of two or three axes that intersect each other at right angles forming rectangles. Any point within the rectangular space can be identified by the distance and direction from any other point. Also known as rectangular coordinate system.

CASCADE CONTROL. An automatic control system in which the control units, linked in sequence, feed into one another in succession, each regulating the operation of the next in line.

CASSETTE RECORDER. A peripheral device for transferring data to or from a cassette tape.

CASSETTE TAPE. Magnetic tape stored on spools within a standard cartridge - self-contained and operable from a cassette recorder.

CATHODE RAY TUBE (CRT). An electronic vacuum tube in which an electron beam can be focused on a small area of a luminescent screen and varied in position and intensity to form alphanumeric or graphic representations.

C AXIS. An angle defining rotary motion of a machine tool part or slide around the Z axis.

CENTRAL PROCESSING UNIT (CPU). The portion of a computer that is the basic memory or logic. It includes the circuits controlling the interpretation and execution of instructions. Also known as the processor, frame, or main frame.

CHAD. The tiny piece of paper removed when a hole is punched into a card or paper tape.

CHANNEL. (1) That portion of a computer's storage medium which is also accessible to a given reading station. (2) That part of a communication system that connects the message source with the message sink. (3) A path along which signals can be sent, e.g., a data channel, output channel. (4) The portion of a storage medium that is accessible to a given reading or writing station e.g., track, bank. (5) In communication, a means of transmission. Several channels may share common equipment. For example, in frequency multiplexing carrier systems, each channel uses a particular frequency band that is reserved for it.

CHARACTER. One of a set of elements which may be arranged in ordered groups to express information. Each character has two forms: (1) a man-intelligible form, the graphic, including the decimal digits 0-9, and letters A-Z, punctuation marks, and other formatting and control symbols; and (2) its computer intelligible form, the code, consisting of a group of binary bits.

CHIP. (1) A small piece of semiconductor material on which electrical components are formed; an electronic circuit element prior to the addition of terminal connections and prior to being encased. (2) A piece of silicon cut from a slice by scribing or breaking, possibly containing one or more circuits but packaged as a unit. Also known as a die. An electronic circuit element prior to having terminal connections added and prior to being encased for physical protection.

CINTURN II. A programming system customized to the capabilities, ranges, and specification of
CINTURN NC Turning and Chucking Centers. CINTURN II Programming utilizes the speed and power of the Fortran computer language to generate part programs written in APT. The CINTURN II programming system is designed to process parts in three simple steps; (1) describe the part by its geometry. (3) describe the roughing operation. (3) describe the finishing operation. Using the corner concept, parts are defined by diameter and length dimensions.

CIRCUIT BREAKER. Refers to various devices for opening electric circuits under abnormal operating conditions; e.g. excessive current, heat, high ambient radiation level, etc. Also called constant breaker.

CIRCUIT, INTEGRATED (IC). Refers to one of several logic circuits, gates, flip-flops which are etched on single crystals, ceramics or other semiconductor materials and designed to use geometric etching and conductive ink or chemical deposition techniques all within a hermetically sealed chip. Some chips with many resistors and transistors are extremely tiny, others are in effect "sandwiches" of individual chips.

CIRCUIT, PRINTED. Refers to resistors, capacitors, diodes, transistors and other circuit elements which are mounted on cards and interconnected by conductor deposits. These special cards are treated with light-sensitive emulsion and exposed. The light thus fixes the areas to be retained and an acid bath eats away those portions which are designed to be destroyed. The base is usually a copper clad card.

CIRCULAR INTERPOLATION. The control of a cutting tool in a complete circle or arc by a machine control unit which has been given basic statements such as coordinates of center point, radius, direction of travel, and coordinate locations of arc end points.
CLOCK. (1) The most basic source of synchronizing signals in most electronic equipment, especially computers. (2) That specific device or unit designed to time events. (3) A data communications clock which controls the timing of bits sent in a data stream, and controls the timing of the sampling of bits received in a data stream.

CLOSED LOOP. (1) A circuit in which the output is continuously fed back to its source for constant comparison. Also a group of indefinitely repeated computer instructions. (2) The complete signal path in a control system represented as a group of units connected in such a manner that a signal started at any point follows a closed path and can be traced back to that point.

CLOSED LOOP SYSTEM. A system in which a reference signal from a controller is compared with a position signal generated by a monitoring unit on the machine tool (feedback). The difference is used to adjust the machine tool to reduce the difference to zero.

CL TAPE. Abbreviation for either "center line" or "cutter line" tape which is the initial output of a computerized NC program giving the coordinate locations of where the cutting tool center line will travel to machine the workpiece. The program is then post processed to take into account the particular features of the machine tool/control unit combination on which the program will actually be run and the part produced.

COBOL (COMMON BUSINESS-ORIENTED LANGUAGE). An English-style programming language oriented to business applications.

CODE. (1) A system of organized symbols (bits) representing information in a language that can be understood and handled by a control system. (2) A system of symbols that can be used by machines such as computers. Special external meaning is dictated by the specific arrangement of the symbols.

COMMAND. (1) A pulse, signal or set of signals that initiate a performance. (2) A signal from a machine control unit that initiates one step in a complete program.

COMMUNICATION INTERFACE CIRCUIT. A communications interface circuit (USART) is a peripheral device programmed by the CPU to operate using virtually any serial data transmission technique currently in use. It will typically have a speed of 4 megabits per second for synchronous operation and 250 kilobits per second for asynchronous operations. (USART refers to Universal Synchronous/Asynchronous Receiver/Transmitter.)

COMPACT II. A universal NC programming system for point-to-point and contouring applications on mills, drills, lathes (including 4 axes), punches, flame cutters and EDM machines.

COMPUTER-AIDED DESIGN (CAD). (1) Any computer system or program that supports the design process. Both business and scientific systems are included. (2) The use of computers to assist Engineering Design in developing, producing, and evaluating design, data, and drawings. (For brevity, CAD is also referred to as the organization engaged in computer-aided design.)

COMPUTER-AIDED MANUFACTURING (CAM). (1) The use of computers to aid in the various phases of manufacturing. Numerical Control (NC) is a subset of CAM. (2) The effective utilization of computer technology in the management, control, and operations of the manufacturing facility through either direct or indirect computer interface with the physical and human resources of the company.

COMPUTER GRAPHICS. The process of communicating between a person and a computer in which the computer input and output are pictorial in nature, having the form of charts, drawings, or graphs. Cathode ray tubes, curve tracers, mechanical plotting boards, coordinate digitizers, and light pens are employed in the creation of graphic design.

COMPUTER-INTEGRATED MANUFACTURING SYSTEM (CIMS). A multimachine manufacturing complex linked by a material handling system and including features such as toolchangers and load/unload stations. Under the control of a computer, various workpieces are introduced into the system, then randomly and simultaneously transported to the NC machine tools and other processing stations.

COMPUTER NUMERICAL CONTROL (CNC). A self-contained NC system for a single machine tool utilizing a dedicated computer controlled by stored instructions to perform some or all of the basic NC functions. Punched tape and tape readers are not used except possibly as backup in the event of computer failure. Through a direct link to a central processor, the CNC system can become part of a Direct Numerical Control (DNC) system.

COMPUTER PART PROGRAMMING. The preparation of a manuscript, in an NC computer language, to define the necessary calculations to be performed by the computer.

COMPUTER PROGRAM. A detailed set or series of instructions or statements in a form acceptable as input to a computer to achieve a specific result.

CONFIGURATION. (1) A group of units that are interconnected and arranged to operate, as a system. (2) The arrangement of software routines or hardware instructions when combined to operate as a system.

CONTINUOUS PATH OPERATION. An operation in which the rate and direction of relative movement of machine members are under continuous control so that the machine travels through the designated path at a specified rate without pausing.

CONTINUOUS PRODUCTION. A production system in which the productive units are organized and sequenced according to the steps to produce the product. The routing of the jobs is fixed and set ups are seldom changed.

CONTOURING. Also known as "continuous path" is the method of NC machining where the control system generates a contour by keeping the cutting tool in constant contact with the workpiece.


CONTOURING CONTROL SYSTEM. An NC system that generates a contour by controlling a machine or cutting tool in a path resulting from the coordinated, simultaneous motion of two or more axes.

CONTROL. Measurement of performance or actions and comparison with established standards in order to maintain performance and actions within permissible limits of variance from the standard. May involve taking corrective action to bring performance into line with the plan or standards.

CONTROL SYSTEM. An arrangement of interconnecting elements which interact to maintain a specific machine condition or modify it in a prescribed manner.

CONTROLLER. (1) An element or group of elements that take data proportional to the difference between input and output of a device or system and convert this data into power used to restore agreement between input and output. (2) A module or specific device which operates automatically to regulate a controlled variable or system.

CORE. Refers to tiny "doughnuts" or magnetizable metal that can be in either an on or off state and can represent either a binary 1 (on) or binary 0 (off). Commonly called magnetic core and formerly used as the basic type of main memory for many computers.

CONVERSATIONAL MODE. Communication between a human operator and a computer via a keyboard terminal or other input/output device. Questions and responses are elicited from the computer by the operator and vice versa.

CRITERION. Refers to a value used for testing, comparing, or judging; e.g., in determining whether a condition is plus or minus, true or false; also, a rule or test for making a decision in a computer or by humans.

CROSS ASSEMBLER. (1) Refers to a program run on one computer for the purpose of translating instructions for a different computer. (2) Programs are usually assembled by the same assembler or assembly program contained within or used by the processor on which they will be run. Many microprocessor programs, however, are assembled by other computer processors whether they be standard, time-shared, mini or other microcomputers. This process is referred to as cross-assembly, and the programs are not designed for specific microprocessors but are to be used on other computers. They are known as cross-assemblers.

CROSS TALK. Generally cross talk occurs when signals on one circuit emerge on another circuit as interference. The circuit which is the source of the signals is known as the disturbing circuit, and that on which the signals are heard is the disturbed circuit.

CRYOGENICS. The area of technology that uses properties assumed by metals at extremely low temperatures.

CURSOR. A visual movable pointer used on a CRT screen to indicate the position at which data entry or editing is to occur.

CUTS II. Computerized part generation system written by Warner and Swasey for their SC line of turning machines.

CUTTER COMPENSATION. A method of adjusting for the difference between the actual and programmed size of a tool.

CUTTER LOCATION (CL) DATA. (1) Information describing the coordinates of the path of the cutter center resulting from a computer program. Common to all machine tool system combinations this information serves as input to the post-processor. (2) The file produced by numerical control systems containing the cutting tool center line at the tip of the tool with an assumed orientation perpendicular to the XY plane unless otherwise indicated. (See CL TAPE.)

CUTTER OFFSET. (1) The difference between a part surface and the axial center of a cutter or cutter path during a machining operation. (2) An NC feature enabling a machine operator to use an oversized or undersized cutter.

CUTTER PATH. The cutting path described by the cutter center.

CUTTING SPEED. The relative velocity, usually expressed in feet per minute, between a cutting tool and the surface of the material from which it is removing stock.

CYBERNETICS. (1) The field of technology relating to the comparative study of the control and communications of information-handling machines and living organisms. (2) The diverse field encompasses a) integration of communication, control and systems theories; b) development of systems engineering technology; and c) practical applications at both the hardware and software levels. The term was originated by Norbert Wiener, American mathematician (1894-1964) from the Greek word for "steersman." Recent and projected developments in cybernetics are taking place in at least five important areas: technological forecasting and assessment, complex systems modeling, policy analysis, pattern recognition, and artificial intelligence.

CYCLE. (1) A sequence of operations repeated regularly. (2) The time necessary for one sequence of operations to occur.


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