4) CMM Intro

Question 1

What is the contact between the CMM and the part?

Answer 1

Touch trigger probe - stylus that tells machine when contact is made.

Question 1

What do CMM’s measure?

Answer 1

Data points in space - cartesian or polar coordinates

Question 2

What are examples of large scale CMM shapes?

Answer 2

• Bridge type
• Gantry type (large scale/ automotive)

Question 3

Where are Optical CMM’s used?

Answer 3

for use when a product cant be touched.

Question 4

What is the advantage of a Multi axis arm CMM?

Answer 4

Portable measurement arm

Question 5

What are pros and cons of hand held scanner CMM’s?

Answer 5

• Portable and useable
• Excess data produced
• Analysis of data takes time and money
• Another step compared to traditional CMM

Question 6

What are the key issues with CMM’s?

Answer 6

• Coordinate measurement principles
• Encoder design
• Touch Trigger Probes
• GD & T principles
• Errors and uncertainties
• Verification and calibration
• CMM measurement application