Inside the IMTS 2016 Quality Assurance Pavilion
The Quality Assurance Pavilion at IMTS 2016 (Sept. 12 -17, McCormick Place, Chicago) features metrology equipment and systems that keep processes on track, as well as the equipment that will check the accuracy of machines. Visitors can immerse themselves in technology that reduces the necessity for stand-alone work cells and offers increased inspection abilities for both materials and features. The Quality Assurance Pavilion is located in the East Building of McCormick Place.
To discuss the latest trends in QA technologies, IMTS Insider turned to a conversation between R. Stephen Flynn, President of Optical Gaging Products (OGP®), and Peter R. Eelman, Vice President – Exhibitions & Business Development, AMT — The Association For Manufacturing Technology, the parent organization of IMTS.
Peter: What are some of the newest technologies being showcased at the Quality Assurance Pavilion?
Steve: Advances in optics and metrology grade cameras have led to a new class of Large Field of View (LFOV) video measuring systems, systems that can image as much as 3 or 4 square inches of a part and make dimensional measurements instantly. There are several makers of these systems — mainly simple benchtop models designed for easy use by virtually any operator. In the main, these are 2D measuring systems for thin, flat parts, and they are generally middle-grade machines in terms of accuracy. However, there are also some new models in this category that offer 3D measuring capability and high precision. These are very high-grade machines with sub-micron accuracy.
Peter: Looking back just five or 10 years, how have these technologies changed?
Steve: The massive improvements in computers and electronics over the past 5 to 10 years has raised the bar for all quality and metrology systems — most especially non-contact metrology. The benchmark performance (speed and accuracy) of a video measuring system has easily doubled in the past 10 years, while the cost has remained about the same.
Recent improvements in software and analysis tools allow coordinate measurements to be compared directly to CAD models. Very complex GD&T (geometric dimensioning and tolerancing) scenarios can be evaluated instantly, and predictive models allow a tightly closed loop between CAD, CAM systems and dimensional measurement systems.
Peter: What is possible now that wasn’t possible 5 to 10 years ago?
Steve: Non-contact 3D characterization of complex shapes and surfaces is the most significant advancement in the past few years. Miniaturized laser, white light, chromatic and interferometric sensors allow very rapid, non-contact measurement of surfaces, bores and asymmetric shapes that previously required hard gaging or contact probing.
Peter: How are users benefitting from these new technologies?
Steve: Manufacturers benefit from these improvements in three main ways:
- Measurement data is available quickly enough to make real-time process adjustments. We are no longer finding out last week’s batch of parts are bad; we know almost immediately when a process is approaching control limits and can make adjustments before producing bad parts.
- We can automatically measure dimensions near the production line that previously required highly skilled and experienced toolmakers to measure in a lab. As precision has become more automated, we’ve been able to integrate it more closely into the manufacturing chain.
- We can normalize data from multiple measuring machines or multiple locations/suppliers and compare them directly to CAD models. Taking the feedback all the way back to the design stage allows manufacturers to design parts so they are easier to make and still meet the design intent.
Peter: How are the technologies changing the way users operate and/or addressing operational issues?
Steve: At the low end, many measurements can now be made right on the shop floor by operators with little or no metrology training. The benchtop LFOV systems allow parts to be placed randomly without fixturing and measured without so much as calling up the routine. The system recognizes the part and measures the critical dimensions automatically. As precision measurement becomes simple and easy, it becomes practical to do more of it – which results in improved quality and lower costs.
For more complex parts, the ability to program the measurement routine directly from CAD shortens the set-up time and reduces the skill level needed to properly set up a part. Again, as measurement becomes easier, it is used more often and more effectively.
Peter: Measurement system technology goes hand-in-hand with the Industrial Internet of Things, doesn’t it?
Steve: The concept of Smart Manufacturing — Manufacturing 4.0, as it’s known in Europe, or the Industrial Internet of Things, as it’s sometimes called in the U.S. — imagines a world in which virtually everything in the manufacturing chain is “connected.” The location, status, condition and next operation of tools and material are all instantly available to the manufacturing data stream. Adding measuring system calibration status and in-process part tolerance status to that data stream closes the loop between quality and manufacturing ever more tightly. In theory, a measuring system could automatically choose to do a probe calibration if it sensed that readings were going out of tolerance and re-measure a part before assuming the part is bad. The IIoT would signal that this has taken place.
Peter: Are there other large trends such as IIoT that impact coordinate measuring systems?
Steve: There are several large trends that are impacting not only metrology but all aspects of the manufacturing chain. One of these is the trend toward model-based engineering (MBE) in which the CAD model is the central repository of all information about a part — not only its dimensions and material, but rich detail about the manufacturing process. Previously, CAD models described finished parts very accurately, but contained no information about how they should be made. Even tolerances were not embedded in the model but appended as text on the drawing, making for a laborious process of entering tolerances into CMM programs and GD&T evaluation software.
Inclusion of this Product Manufacturing Information (PMI) in 3D CAD models now means that the measuring system has a prior knowledge of the manufacturing technique, as well as the part’s nominal dimensions and tolerances. CMM programming time is vastly reduced, because all the parameters necessary for measurement are now in the CAD model. Load the CAD model, and 90% of the measurement set-up is complete. With this capability, things such as the selection of sensors, filtering of datapoints, and many other aspects of CMM set-up that currently rely on the judgment of the individual programming of the CMM now are specified in the part’s 3D CAD documentation.