This CMM use case demonstrates how overcoming this inertia is essential to staying competitive.
Continuous improvement is the name of the game in manufacturing, paring away inefficiencies and making projects more profitable–something management gets very excited about. However, while some improvements can be made with small investments, such as kanban cards or kaizen bins, other process improvements require more significant investments. Bringing in new technology costs hundreds of thousands to millions of dollars. And the initial outlay for a piece of equipment is just the beginning. Training, upskilling and shop space may be associated costs. When it comes time to open the checkbook, some manufacturing decision-makers start singing a different tune: why do we need these improvements again? What’s wrong with the old process?
When it’s time to change, manufacturers may face technological inertia, the phenomenon by which the accumulated knowledge and experience with one technology exerts a pressure against effectively using a new technology. One example of this is the portable coordinate measuring machine, or CMM arm, which can drastically reduce inspection times and drive immediate production quality improvements.
So how can manufacturing managers successfully navigate an opportunity to invest in new technology to improve a process, without getting stuck in the inertia of the known?
What is technological inertia?
One example of technological inertia might take place at a busy doctor’s office considering a transition from x-ray to CT scans: it’s more complicated than just buying the machine, because:
- technicians know how to take x-rays and may require new training
- patients are already familiar with what’s required for an x-ray
- Doctors are more experienced in interpreting x-rays than CT scans.
- The business can’t afford to see a ‘dip’ in quality of care during an adjustment period.
So, instead of investing in the CT scanner, the business may purchase more x-ray machines, to keep up with increasing demand without having to adopt the new generation of technology. In this way, the inertia of the old technology inhibits any improvements the new technology could bring.
Overcoming this inertia to realize the benefits of a new technology is essential for companies to stay competitive and drive profits.
To learn more about how manufacturing decision makers can overcome this inertia and find their way to the other side, engineering.com spoke to two engineering and metrology professionals with experience not only with portable CMM arms, but also the technology and processes they replace, such as manual measurement techniques like plate layout, verniers, and gauge blocks; but also the venerable bridge CMM in the climate-controlled quality lab.
Alex Dunn is a Manufacturing Engineer and Measurement Specialist with ten years experience in the gas turbine manufacturing industry. He’s watched as portable measurement arms have developed from early models limited in accuracy, to today’s models which may rival the accuracy of the bridge CMM.
Fabrizio Beninati is the owner of Frontier Metrology, a metrology service provider and FARO distributor based in Ontario, Canada. Working with FARO and Polyworks, Fabrizio has seen the full gamut of metrology workflows, from the creative to the archaic, as he demos and promotes the capability of the portable FARO arm equipped with a laser line scanner.
Quality and Metrology in Manufacturing
Ever since the industrial revolution brought the innovation of interchangeable parts, measurement and quality control have been essential parts of manufacturing. Tolerances limiting the variation of part dimensions are set by engineers according to the requirements of the part, and quality control processes ensure that production matches those dimensions accurately, within set tolerances. The instruments that enable quality control include the humblest tape measure in the construction industry, to the ISO 10360 certified, gold-tipped Zeiss CMM with 0.3 µm accuracy, and everything in between.
A few common metrology solutions in manufacturing include:
- Manual instruments such as micrometers, depth gauges and verniers
- Granite surface plates used in conjunction with tools such as height gauges, gauge blocks, and dial indicators
- Optical devices such as comparators, shadowgraphs, and profile projectors
- A typical 3-axis bridge or gantry CMM, which can be programmed to take highly-accurate measurements using probe contact
- Portable CMMs, which digitally read the joint positions of an arm to interpret the 3D position of the measurement device, such as a probe or digital optical system.
- Digital optical systems, such as 3D scanners.
- CAD software is an essential part of digital metrology solutions, as collected measurement data can be compared to the CAD model reference to determine and report on deviations.
For manufacturers used to one of these processes, inertia including personnel training, costs of new equipment, and lack of knowledge of the benefits and ROI of new alternatives make it difficult to implement new solutions, such as portable CMM.
Advantages and applications of Portable CMM
In the typical machine shop or fabrication shop, the headache of metrology is that manual tools such as verniers are fast but not sufficiently accurate or repeatable, while the bridge CMM is highly accurate–even surpassing many projects tolerance requirements–but too slow, especially for new projects, when it needs to be programmed. In Alex Dunn’s experience as a Measurement Specialist, while many of the arm CMMs on the market today can’t match the accuracy of a bridge CMM, they can typically hold tolerances above 1 thou. For applications with more relaxed tolerances, such as fabrication, the speed and flexibility of portable CMMs is unmatched. “You grab the arm, calibrate the probe once, you don’t have to worry about calibrating different angles, different styli. You just calibrate the probe and it’s good for the whole volume of measurement. You’re not concerned with crashing the machine. You’re not concerned with having to bring parts into the temperature controlled lab. You get to go to your parts,” explained Dunn. “The big power of a bridge CMM is automation. If you have a high volume of parts that need to be measured, you program the machine and you can train an operator to run the machine, get the data, and do what they need to do with the parts.” While this automation makes for a faster process at high volumes, it also comes with costs.
First, the CMM needs to be programmed, not unlike a CNC mill, to make the movements required to bring the probe to touch off at each measurement location. Secondly, a CMM is a very expensive piece of equipment. If the quill or the probe crash into the part, you’ve not only scrapped a part, but the CMM must now be calibrated or repaired. “If you don’t have high volume, the portable solution is much faster because you’re not programming a machine,” said Dunn. “You’re just simply operating the instrument physically, so you’re not going to be concerned with your clearance planes, or your stylus calibration. You can obviously damage your part if you hit it with the instrument, but the risk of collision is much less. You can very rapidly get the measurement you need and move the part on. So you gain a lot of speed in that regard.”
Dunn recommends the Hexagon Romer arm. “If you pair that with the [Hexagon] AS1 laser line scanner, which I was fortunate enough to have at a previous employer, you can tackle a lot of projects with that because you have the ability to do touch probing as well as scanning for large surfaces.”
This pain point of slow cycle time is why many customers call Fabrizio Beninati at Frontier Metrology to learn about arm CMM technology. For Beninati, understanding the advantages and applications of portable CMM systems is key to not only selling them as a distributor, but also using them himself as a metrology service provider.
Beninati finds that many manufacturers in the automotive industry are moving some inspection tasks to portable CMM solutions, finding conventional CMM too slow and cumbersome. “A lot of our clients are leaving the CMM behind, or dedicating the CMM to the high precision work and switching to the arm to do a higher volume of parts.” with the arm and laser line scanner in conjunction with polyworks, said Beninati, “customers are able to quickly scan and target what they need and generate a report in a fraction of the time.” Beninati recommends a FARO arm in conjunction with a laser line scanner and Polyworks software to quickly and easily capture measurement data and use frame of reference inspection to detect and measure deviation.
“CMM is slow, it’s methodical, it’s delicate work,” said Beninati. “You don’t rush CMM because probes are expensive, the machines expensive, everything is very methodical in the CMM world. The arm is more freehanded and forgiving to capture data.”
Beninati echoed Dunn in the idea that while portable systems may not be able to measure as accurately as bridge CMMs today, they still find applications in precision manufacturing. “We have customers that use a bridge CMM for their initial process capability studies, and they say once we’re within our values now we’ll just inspect using the FARO arm because you can do tenfold more vs the CMM.” Both Dunn and Beninati anticipate the accuracy rating of portable systems creeping up in the future, to rival that of larger machines.
How to Overcome Technological Inertia and Improve Manufacturing Processes
According to Beninati, technological inertia is a major reason why manufacturers drag their feet or fail to upgrade to faster, more efficient processes, such as a portable CMM. When an aerospace manufacturing shop hired Beninati as a service provider to do inspection using the FARO arm, he pitched a portable system for the customer to buy, so that they could implement it in-house. “They told me they use shadowgraphs. They measure using a shadow and grid cells, counting them out manually,” he explained. “It works, and they say, ‘why improve it? Why get an arm?’ they can just do it by counting.”
Stay up to date
The leaders who successfully navigate a technology change are those who empower themselves and their teams with knowledge about new emerging technologies. Without an understanding of emerging technologies, it’s impossible to see how they may apply in your processes. Beninati highlighted trade shows and supplier demos as key tools for manufacturing leaders to help stay in the know.
“Find those couple trade shows that are on the cutting edge,” said Beninati. “That’s the vendors’ time to shine. Go to trade shows where the big players go, and see the new and emerging technologies. Stay open to possibilities.”
Dunn also highlighted demos as a key knowledge tool. “I always advise folks, if you’re interested in any of these instruments contact the suppliers because it’s their job to demo the equipment and bring application engineers to you,” he said. “You can put the product right in front of them and say, ‘show me how to measure it,’ And it’s their job to prove to you that they can. Then everyone wins.”
Upskill employees
Part of technological inertia is cultural. It’s natural for individuals, especially in their jobs, to resist and fear change and the instability it may bring. When a new technology reduces labor hours required for a process, workers may wonder if they will lose those hours. Communication is key to confronting this mindset and assuaging these fears. Managers can address these fears by highlighting the benefits of upskilling for employees.
“I’ve seen cases where workers want the arm because they see it as a new skill set, a new and emerging technology,” said Beninati. “But I’ve also seen quality teams who have seen it as a threat to their jobs.” However, in his experience, customers that do get started with a portable CMM find applications for both the new instrument as well as their existing CMM, for example, leading to more opportunities for metrology personnel than before.
Plan funding strategically
If there is no budget, the benefits of a new technology don’t matter. Beninati has seen this firsthand as a supplier. When a customer assembling parts sourced from many suppliers began seeing quality variations, they implemented a manual metrology process using height gauges and blocks to measure each assembly by hand. “They were taking up to 3 hours for each assembly,” recalled Beninati. “I went in there, did the demo, scanned it in like 3 minutes, and even had their guy–who had never touched a FARO arm–try it. It took him 8 minutes, so I said, ‘How many can I put you down for?’ And we all laughed, but today it’s waiting on upper management.” Even though Beninati and the FARO arm demonstrated crystal clear ROI, cost stood in the way.
“If you’re an OEM supplier or plant and you secure that big contract, you’ve already put in your budget the building expansion, the new tools, new equipment. So in for a penny, in for a pound. You didn’t put in that FARO arm because you’re going to do it with verniers and calipers, you’re committed until the next job comes around.”
In Dunn’s experience, that’s the best time to propose technological change: when new money comes in along with a new contract.
“Usually when your processes are locked in place and you’re used to a certain amount of revenue from your parts, it’s really really hard to go to management and say, ‘we need you to eat into those profits so that I can have this piece of equipment.’ They’re going to say, ‘why? I’m making this money, and you’re telling me I’ll make less money to deliver the same product?’ That’s a really hard thing to sell,” he explained. When budgeting new money to different project needs, it’s easier for employees to propose new technology using the funds earmarked for the existing process. “Let’s say $40,000 is all it takes to get a standard probing package arm,” said Dunn. “You can buy 40,000 worth of gauges no problem. So at that point, you can approach management and say hey, here’s a solution that will work for this project, the money is set aside for it, and we can then use the piece of equipment to improve other processes in future.”
Listen to employee experience
Lastly, in addition to suppliers and trade shows, your employees have knowledge of new technologies and alternative ways of doing processes that you can unlock. As experienced machinists, engineers and workers move around the industry, they carry knowledge of how the industry is moving forward, and they bring this knowledge to your company.
“Who is more likely to be aware and plugged into these technologies? It’s gonna be your shop floor guys,” said Dunn. “a lot of employees arrive at your shop with experience with other equipment, and bring that knowledge and advice. That opens doors and minds to new alternatives. Management can’t spread themselves so thin as to become as intimately familiar with the process as well as a machinist or fabricator. So, good managers listen to their employees.”
Where will your next process improvement take you?
While technological inertia has sunk many ships across industries and sectors, the keys to navigating it come down to basic, effective management practices:
- Stay up to date in your industry
- Leverage the experience of your employees
- Understand the ROI
- Don’t fear change
Armed with these principles, you’ll be ready to ride the next technological wave and stay ahead of the competition.