Z94.12.3 M - Manufacturing Automation & Computer Control

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M FUNCTION. Similar to a G function except that the m functions control miscellaneous functions of the machine tool such as turning on and off coolant or operating power clamps and so on.

MACHINE ATTENTION TIME. That portion of a machining operation during which the workman performs no physical work yet must watch the progress of the work and be available to make necessary adjustments, initiate subsequent steps or stages of the operation at the proper time, and the like.

MACHINE LANGUAGE. (1) A language written in symbols, bits, characters, signs, or a series of bits to convey to a computer instructions or information to be processed. (2) The lowest level language, usually different for every computer type. Machine language is written directly by the binary code and does not require a compiler or assembler program to convert from symbolic code to binary-coded machine instructions.

MACHINE TOOL. A powered machine used to form a part, typically by the action of a tool moving in relation to the workpiece.

MACHINE UTILIZATION. The percent of time that a machine is running production as opposed to idle time. (cf. idle time, running time.)

MACHINE VISION (COMPUTER VISION). Computer perception, based on visual sensory input, to develop a concise description of a scene depicted in an image. The term is used synonymously with image understanding and scene analysis.

MACHINING CENTER. A machine tool, usually numerically controlled, that can automatically drill, ream, tap, mill, and bore workpieces. It is often equipped with a system for automatic toolchanging.

MACRO. (1) A powerful computer instruction from which a string of micro instructions can be called as a unit. (2) A source language instruction from which many instructions can be generated. Also known as macro instruction, macro program, or macro routine.

MAGNETIC DISK. A rotating circular plate that is coated or permeated with magnetic material on which information is recorded and stored for subsequent use.

MAGNETIC TAPE. A plastic, metal, or paper tape that is coated or permeated with magnetic material. It is capable of storing data by selective polarization of portions of the surface.

MAINFRAME. Refers to the basic or main part of the computer, i.e., the arithmetic or logic unit. The central processing unit.

MAINTENANCE. Maintenance and repair of physical plant and materials handling equipment. Any activity intended to eliminate faults or to keep hardware or programs in satisfactory working condition, including tests, measurements, replacements, adjustments and repairs.

MANAGEMENT INFORMATION SYSTEM (MIS). An information feedback system in which data is recorded and processed for use by management personnel in decision making.

MANIPULATED VARIABLE. That quantity or condition which is altered by the controller and applied to the controlled system.

MANUAL CONTROL. Machine or process control performed by a person.

MANUAL DATA INPUT (MDI). A means of manually inserting commands and other data into an NC control.

MANUAL PART PROGRAMMING. The preparation of a manuscript in machine control language and format to define a sequence of commands required to accomplish a given task on an NC machine.

MANUFACTURING. A series of interrelated activities and operations involving the design, material selection, planning, production, quality assurance, management, and marketing of discrete consumer and durable goods.

MANUFACTURING PROCESS. The series of activities performed upon material to convert it from the raw or semifinished state to a state of further completion and a greater value.

MANUSCRIPT. Form used by a part programmer to organize machining instructions. From it a computer program is prepared. Refer also to part program.

MASK. (1) A pattern of characters that controls the retention or elimination of portions of another pattern of characters. (2) A filter.

MASS PRODUCTION. A method of quantity production in which a high degree of planning, specialization of equipment and labor, and integrated utilization of all productive factors are the outstanding characteristics.

MDCAPT. An APT system that provides enhanced part programming capabilities for machined parts ranging from the most simple to the ultimate in complexity.

MEASUREMENT. The process of determining the numerical value of dimensions or factors, determining the quality, extent or degree of the dimensions or factors of a process or workpiece.

MEMORY. (1) One of the three basic components of a CPU memory that stores information for future use. Storage and memory are interchangeable expressions. Memories accept and hold binary numbers or images. (2) In order to be effective, a computer must be capable of storing the data it is to operate on as well as the program that dictates which operations are to be performed. Not only must that memory unit of a computer store large amounts of information, the memory must be designed to allow rapid access to any particular portion of that information. Speed, size and cost are the critical criteria in any storage unit. Various types are: disc, drum, semi-conductor, magnetic core, charge-coupled devices, bubble domain, etc.

MEMORY CYCLE. (1) A computer operation consisting of reading from and writing into memory. (2) The time required to complete this process.

METALMATS. Metalmats is programmed to run on Radio Shack TRS-80 Model 2 or IBM 370 mainframe equipment. Programs include machining, welding/fabrication, and assembly for medium to large job shops. It establishes time standards and provides a routing chart which includes process, manual, and setup times for almost all metal working operations.

MICROCOMPUTER. A general term referring to a complete tiny computing system, consisting of hardware and software, whose main processing blocks are made of semiconductor integrated circuits. In function and structure it is somewhat similar to a minicomputer, with the main difference being price, size, speed of execution and computing power. The hardware of a microcomputer consists of the microprocessing unit (MPU) which is usually assembled on a PC board with memory and auxiliary circuits. Power supplies, control console, and cabinet are separate.

MICROCONTROLLER. This can mean a microprogrammed machine, a microprocessor or a microcomputer used in a control operation-that is, to direct or make changes in a process of operation. Microcontroller refers to any device or instrument that controls a process with high resolution, usually over a narrow region.

MICROPROCESSOR. The semiconductor central processing unit (CPU) and one of the principal components of the microcomputer. The elements of the microcomputer. The elements of the microprocessor are frequently contained on a single chip or within the same package but sometimes distributed over several separate chips. In a microcomputer with a fixed instruction set, it consists of the arithmetic logic unit and control logic unit. In a microcomputer with a microprogrammed instruction set, it contains an additional control memory unit.

MINICOMPUTER. (1) A small, general-purpose computer which has from 4K to 4mb words of memory and employs words of 8, 12, 16, 18, 24 or 32 bits in its basic configuration. Generally a minicomputer is a mainframe that sells for less than $100,000. Usually it is a parallel binary system with 8, 12, 16, 18, 24 or 36-bit word length incorporating semiconductor or magnetic core memory offering from 4K words to 4mb words of storage and a cycle time of 0.2 to 8 microseconds or less. A bare minicomputer (one without cabinet, consol, and power supplies) consisting of a single PC card can sell for less than $1000 in OEM quantities. (2) These units are characterized by higher performance than microcomputers or programmable calculators, richer instruction sets, higher price and a proliferation of high level languages, operating systems, and networking methodologies.

MIRROR IMAGE PROGRAMMING. A feature of some machine control units that provides for a specific axis by means of a switch. This means that a single program can produce two parts that are mirror images.

MISCELLANEOUS FUNCTION. One of a group of special or auxiliary functions of a machine, such as spindle stop coolant control, program stop, and clamp control.

MNEMONIC. A combination of letters, numbers, pictures, or words that aids in recalling a memory location or computer operation.

MODEM. Refers to a MODulation/DEModulation chip or device that enables computers and terminals to communicate over telephone circuits.

MODULE. An interchangeable hardware subassembly containing electronic components that can be combined with other interchangeable subassemblies to form a complete unit.

MOLECULAR MANUFACTURING. The construction of objects to complex, atomic specifications using sequences of chemical reactions directed by nonbiological molecular machinery. It is the use of nanoscale mechanical systems to guide the placement of reactive molecules, building complex structures with atom-by-atom control.

MOLECULAR NANOTECHNOLOGY. Comprises molecular manu- facturing together with its techniques, its products, and their design and analysis; it describes the field as a whole.

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