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Laser Telemetric Measuring Systems

This is a high speed gauging system providing accuracy and repeatability of a contact type gauge with versatility of a non-contact type of gauge. The principle is explained below:

A thin band of laser beam projects from a transmitter to receiver. When an object is placed across the beam, the object casts a shadow. The signal from light entering the receiver is used by the microprocessor to detect the shadow and to calculate the dimension represented by the distance between the edges of the shadow. The system consists of three modules:

i. Transmitter module

ii. Receiver module

iii. Processor electronics

(Radhakrishnan P., Subrahmanyan S., Raju V., CAD/CAM/CIM, 3rd Edition, p. 513 )

Laser Interferometer Measuring System

Presently lasers are used as length measuring devices. They are commonly used for positional accuracy measurements. They are also used as length measuring machines of high accuracy (accuracy of the order of 0.01 micrometer). The feedback of this can be used for positioning of the machine and also for computation of measurements. Nowadays it has become a common practice to use laser-measuring system for the calibration of CNC machines.

Using laser-measuring system the measurements performed are reliable, accurate and faster compared to conventional methods. The laser interferometer can be directly interfaced with a computer. This makes it easy for the operator to evaluate the results as per the evaluation procedures mentioned in various standards like AMT, AFNOR, VDI, MTTA, and JIS etc. Using different attachments laser interferometer is also used for other measurements like straightness, flatness, squareness, velocity, pitch, yaw etc.

(Radhakrishnan P., Subrahmanyan S., Raju V., CAD/CAM/CIM, 3rd Edition, p. 513 )

Constructive Solid Geometry (CSG)

Primitive instances are combined using Boolean set operations to create complex objects. In a CSG model, physical objects are created by combining basic elementary shapes known as primitives like blocks, cylinders, cones, pyramids and spheres. The Boolean operations like union (∪), difference (–) and intersection ∩ are used to carry out this task.

(Radhakrishnan P., Subrahmanyan S., Raju V., CAD/CAM/CIM, 3rd Edition, p. 143)

Distributed Numerical Control

Sometimes the abbreviation DNC is used to denote distributed numerical control. A computer network for manufacturing may consist of a main frame computer, CAD/CAM work stations, DNC host computer and the CNC systems connected to it. This configuration can be beneficially used for NC data processing. Any complex calculations required for generating NC data can be transferred to the more powerful mainframe computer. Thus the NC DATA processing is done at different hierarchical levels. In a way many of the DNC systems today are in fact distributed processing systems.

(Radhakrishnan P., Subrahmanyan S., Raju V., CAD/CAM/CIM, 3rd Edition, p. 384 )