CMM is a 3D measuring device used to measure dimensional characteristics of objects. It has three main components - a structure, probe system, and controller/software. Traditional CMMs have a fixed gantry structure and use touch probes to manually or automatically measure points. New developments include non-contact probes, faster computing, and portable CMMs suited for shopfloor use.

1. By-
Mayur Andulkar
MTech(CAD CAM)

2.  CMM is a 3D device for measuring 3
dimensional charateristics
 Manual or Automatic control
 Typically 3 axes : X,Y & Z
 Configurations of CMM:
◦ Traditional (Fixed) type
◦ Portable CMM
 Articulated arm
 Laser tracker

4.  3 main components:
◦ Body/ Structure
◦ Probe system
◦ Controller and software
 Structure:
◦ Fixed: Gantry, Cantilever or bridge type
◦ Structure mounted on air bearings
◦ Errors in structure
◦ Structure material: Granite, Ceramic, etc
◦ Temperature sensors: Invar material

5.  Probe System
◦ Mechanical touch type
◦ Touch trigger electronic probe
 Spring loaded steel ball stylus
◦ Optical Probes – CCD camera , 2D image
◦ Scanning probes
 Contact type and non contact type
◦ Micrometrology probes
 Control or Computing System

7.  The structure of CMM has remained the same
 New technology developments in:
◦ Probe system
 Non Contact type
◦ Software and controllers
 Faster computing
◦ Industrial Requirements
 CMM on shopfloor

8.  Multi Sensor Measuring
◦ Incorporates touch, optical or laser sensors
◦ Operator can choose which sensor to use
◦ All work done in single setup
◦ Faster
◦ The co ordinates might not be correct owing to inputs
from many sensors
 5 Axis CMM
◦ Revolutionary technology by Renishaw
◦ 2 axes controlled by servo
◦ Faster and quicker
◦ Not supported by OEM’s

10.  3 D Scanner
◦ Many technologies are used
◦ Color as well as contour information collected
◦ Technology
 Contact type (eg. CMM)
 May damage the object
 Relatively slow
 Non Contact type
 Active (Emit radiations eg. X ray, UV,Infrared etc)
 Passive (Take the radiations emitted naturally)

11.  CMM Retrofitting
◦ Much Less costly
◦ Frame is not damaged much
◦ Software changes can be easily incorporated
◦ Better accuracy and precision by using
advanced probe systems

12.  CAD based Inspection
 Dimensional measurement
 Profile measurement
 Angularity or orientation measurement
 Shaft measurement
 Reverse Engineering

13. Thank You