INTRODUCTION of CMM (Coordinate Measuring Machine) Understanding The CMM: The Coordinate System We use a coordinate system to describe the movements of a measuring machine. The coordinate system, invented by the famous French philosopher and mathematician René Descartes in the early 1600's, lets us locate features relative to other features on workpieces.
A Typical Coordinate Machine
The Map Coordinate System, 4-E-3
Probe to measure features on a workpiece
The Machine Coordinate System
The Part Coordinate System
A probe measures a high-pressure turbine nozzle A probe measures a high-pressure turbine nozzle. The CMM replaced dedicated gages on the shop floor
MICROXCEL PFX direct computer control measuring machine
Our CMM in Hess lab
Project-3 CMM Lab Lab will be held on Week-8 in Hess building Rm. 107 Lab schedule will be same as last two labs Lab report will be handed in on Week-9. Lab time will be approximately 2 hours.
Lab Objective: Familiarize yourself with the CMM and all components Steps needed and importance of qualifying the probe Align block Measure and record dimensions. Lab instruction: A demonstration will be provided on how to take measurements using the CMM. Care should be taken not to touch the slide tracks. When moving the probe, be careful not to bump it into any of the objects mounted on the table. Refer to page 2 of block_measurement.pdf for given dimensions of the block. Create a table to record your data. It should have one column for each group member and one row each for the following types of measurements: (See below for an example) Angle, Diameter, Distance between two holes, radius of curvature, slot length, length and width of block, depth of hole, distance from edge.
Lab output: When taking measurements clearly indicate in a diagram the dimensions you gathered. Verify your measurement with the drawing provided. Then Calculate their distribution and standard deviation of measurements. Optional: You can bring your own part and measure its dimensions.
Member Name Member 1 Member 2 Member 3 Member 4 Member 5 Member 6 Mean Std. Dev. Angle Diameter Distance between 2 holes Radius of Curvature Slot length Length of block Width of block Depth of hole Distance from edge