Coordinate Measuring Machine(CMM)

A Coordinate measuring machine is an electromechanical system design to perform coordinate metrology.
CMMs are also considered as transducers that can convert physical measurements into electrical signals.
They are versatile in their capability to record measurement of complex profiles with high sensitivity (0.0025 mm) and speed.

1. COORDINATE MEASURING MACHINE(CMM)

2. INTRODUCTION The first CMM Devices were probably introduced by the Italian company DEA (Digital Electronic Automation Spa) which introduced a Portal Frame CMM with Hard Probe. A Coordinate measuring machine is an electromechanical system design to perform coordinate metrology. CMMs are also considered as transducers that can convert physical measurements into electrical signals. They are versatile in their capability to record measurement of complex profiles with high sensitivity (0.0025 mm) and speed.

3. DEFINITION A coordinate measuring Machine is a 3D device For measuring the Physical geometrical Characteristics of an object.

4. CMM IN COMPUTER AIDED MANUFACTURING

5. Description The typical 3 "bridge" CMM is composed of three axes, an X, Y and Z. These axes are orthogonal to each other in a typical three dimensional coordinate system. Each axis has a scale system that indicates the location of that axis. The machine will read the input from the touch probe, as directed by the operator or programmer. The machine then uses the X,Y,Z coordinates of each of these points to determine size and position with micrometer precision typically. Reference ..\VIDEO\NX CMM Inspection Programming.mp4

6. COORDINATING MEASURING MACHINE(CMM) ..\VIDEO\UNIVERSAL COORDINATE MEASURING MACHINE.mp4

7. COMPONENTS OF CMM To accomplish measurements in 3-D, a basic CMM is composed of the following components: Probe head and probe to contact the workpart surfaces Mechanical structure that provides motion of the probe in three Cartesian axes and displacement transducers to measure the coordinate values of each axis Drive system and control unit to move each of the three axes Digital computer system with application software ..\VIDEO\Working and principle of Co-ordinate measuring machine (CMM).mp4

8. COMPONENT OF CMM(CONT..) PROBE: The contact probe is a key component of a CMM.lt indicates when contact has been made with the part surface during measurement. The tip of the probe is usually a ruby ball. Ruby is a form of corundum (aluminum oxide), whose desirable properties in this application include high hardness for wear resistance and low density for minimum inertia. Most probes today are touch-trigger probes which actuate when the probe makes contact with the part surface.

9. TYPES OF CMM Ass per the mechanical structure the CMM are classified into six types , which are as follows: CANTILEVER MOVING BRIDGE FIXED BRIDGE HORIZONTAL ARM GANTRY COLUMN

10. MECHANICAL STRUCTURES OF CMM

11. CMM WORKING After placing a workpiece on the machine table, a probe is used to measure different points on it by mapping the x, y, z coordinates. The probe operates either manually via an operator or automatically via a control system. These points are then uploaded to a computer interface where they can be analyzed using modeling software (e.g. CAD) and regression algorithms for further development .