How many Questions are make in CMM for interviews?

cmm machine working principle free ppt

A coordinate measuring machine (CMM) is a device for measuring the physical geometrical characteristics of an object. This machine may be manually controlled by an operator or it may be computer controlled. Measurements are defined by a probe attached to the third moving axis of this machine. Probes may be mechanical, optical, laser, or white light, amongst others. A machine which takes readings in six degrees of freedom and displays these readings in mathematical form is known as a CMM.Coordinate measuring machines (CMMs) are mechanical systems designed to move a measuring probe to determine coordinates of points on a workpiece surface. They provide precise measurements of objects for design, testing, assessment, profiling, and reverse engineering of parts. Machines are available in a wide range of sizes and designs. They use a variety of different interfaces and modeling software.With the advent of numerically controlled machine tools, the demand has grown for some means to support these equipment. There has been growing need to have an apparatus that can do faster first piece inspection and many times, 100% dimensional inspection. The Coordinate Measuring Machine (CMM) plays a vital role in the mechanisation of the inspection process. Some of the CMMs can even be used as layout machines before machining and for checking feature locations after machining. Coordinate measuring machines are relatively recent developments in measurement technology. Basically, they consist of a platform on which the workpiece being measured is placed and moved linearly or rotated. A probe attached to a head capable of lateral and vertical movements records all measurements. Coordinate measuring machines are also called measuring machines. They are versatile in their capability to record measurement of complex profiles with high sensitivity (0.25 m) and speed. In this unit, we will discuss the principle and the working of a Coordinate Measuring Machine (CMM).