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NFL First Downs will be measured with Chains…

Here in the United States our Football is our american sport starting in late summer, we love our baseball, but come Football season the chants of “are you ready for some football” can be heard everywhere. What does that have to do with Metrology? Well, nothing….yet…..

Logo of the National Football League Playoffs,...
Logo of the National Football League Playoffs, 2011–present (Photo credit: Wikipedia)

In the American game of Football the goal is to move the ball down the field to the end zone, the team with the ball is given four chances (“plays”) to advance the ball 10 yards, if they advance it the minimum 10 yards they are rewarded with another four chances (plays) etc, until they reach the “end zone” where a touchdown and 7 points awaits. This ten yards is where Metrology should come in to play…..

Over the last several years the american game of football has used technology to improve the game by adding “instant replay” to determine if the Referee’s made the correct call or to determine if the ball was placed in the correct location on the field. In the National Football League (NFL) and in Colleges speakers have been added to the Quarterback’s helmet (Quarterback is the on field “General” for the Offensive unit) and to the Linebacker’s helmet (Linebacker is the on field “General” for the Defensive unit) so that their coaches can communicate with them so that they can make adjustments in real-time. The use of technologies in the players uniforms, shoes, helmets have improved safety and comfort of the players. Even the balls are kept at an exact temperature to ensure that when they are being kicked everything is “equal”, team benches are heated or cooled depending on the climate, technology is everywhere except…..

The aforementioned measurement of the 10 yards, what the ENTIRE games is based on that 10 yard increment. This 10 yard increment has the largest impact on a game of any one component, millions of dollars are won and lost based on that 10 yard increment, that 10 yards or 30 feet, carries a lot of weight. Jobs are won and lost based on that 10 yards, that 10 yards is everything….so how do you think it is measured in the year 2010 when the ability to measure 30 feet (9.1 meters) is down to the microns? Lasers? Total Stations? Some other sophisticated measurement system? NOPE, sorry the use of two poles and a chain….Sounds like Land Surveying dating as far back as history takes us right?

Measurement Method of the First Down

Several times during an american football game the “chain gang” will be called from the sideline, dragging out their poles and chains and the Referee will by hand “index” the pole to line of chalk, this is where the measurement is taken from, the chain is “stretched” to the tip of the football, to see if the “nose” of the ball exceeds the pole at the other end 10 yards (9.1 meters) away. This is how that all important measurement is taken, to those of us involved in the science of measurement the possibility for inaccurate measurements are endless, but yet, this is what american Football is based on, this has been the way since 1906.

When the Vice President of  officials from the National Football League was asked about this two years ago; he stated that he did not think it was perfectly accurate, and yet nearly two years later there is no advancement in how this crucial measurement is taken, why is that?

To be clear on the procedure that is used here is a quick synopsis;

On a first down, one end of the chains is placed along the sideline by one member of the seven-person chain gang — hired for game-day duty by the home teams — six feet from the field, supposedly even with the front tip of a football (“eyeballed”)  that will be snapped at least 25 yards away. When a play ends, an official estimates the spot, usually marking it with a foot and tossing the ball to another official to set for the next play. When a first down is too close to call, the chains are brought onto the field.

Sometimes the “drive” by the offensive team continues by an inch. Sometimes it ends by less.

There have been several attempts at innovating this process, however, it seems that the “ritual” of calling the markers onto the field, with the suspense it brings as the crowd quiets and watches the referee suddenly concerned with accuracy hold the ball still as the chains are stretched is what stops technology from intervening. The “american football gods” will say that the newer methods are unproven, and could lead to errors in the game, however, these same people would not want to hear how the human eye leads to errors when attempting to align an object 75 feet away.

Perhaps, someone reading this will come up with the system that will change the way the “first down” is measured!

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Summertime Heat offers Measurement Challenges

In the world of dimensional measurement, temperature changes can create challenges to obtaining accurate and precise measurements. For those individuals who must work in environments that are not climate controlled precision measurements can be extremely challenging when the summer months come along, not only are they faced with their own physical challenges of the often overbearing heat, but also the challenges of parts that change size with every tick of the clock.CMSC Weather Forecast

With the advancement in measurement systems and software’s the operators have the ability to control the effects of temperature on their measurement equipment and the parts they measure, however, proper application of these controls is critical to achieving the desired measurement results. Compensation of Thermal Expansion allows Measurement Technicians to correct for changes in part temperature from their “nominal” size (68 deg Fahrenheit or 20 degree Celsius is nominal for most materials), however the Measurement Technician must be aware of when to apply this compensation and how to do it. Unfortunately, this is not always as easy as it should be as every software and every piece of measurement hardware works differently. Some measurement equipment requires Technicians to enter a Temperature for the device, this does not mean that it is compensating for the temperature of the part being measured. If the operator enters a part temperature for the device it will also yield inaccurate measurement data.

So what does all this mean? If you are measuring parts in uncontrolled environments and you are not sure how to properly correct for the temperature and you are looking for accurate and precise measurement data, contact your measurement hardware and software provider for details on properly correcting for the temperature. Note: many devices do not require an air temperature for operation as they are unaffected by temperature (articulating arms as an example) while others typically using Lasers are affected by not only temperature but air pressure and must have accurate values to achieve accurate results.

For those Measurement Technicians out there in the uncontrolled environments working in the heat, stay hydrated and keep measuring!!

Stay hydrated!

How much Data is enough Data?

At the beginning of my career I worked at a large aircraft manufacturer in the Northwest as a Jig Builder; fabricating jigs that ranged from small tabletop size to jigs that were over a hundred feet long and four stories tall. I learned to measure with Vernier Micrometers, Calipers, Height Gages, “Suitcase” Micrometers, Ball Gages, Adjustable Parallels, Transits, Optical Levels, Alignment Scopes etc….Single dimension measurements….it took multiple setups and a great deal of time and skill to properly set tooling details to the tolerances we were working back then (+/- 0.010 inches) and occasionally working as close as +/- 0.005 inches.

Working with single dimension measurement devices often required the use of three different types of measurement devices, three different indexing setups to set a detail in all three directions (X, Y, Z) or in aircraft terms; Station, Buttline, Waterline. This is how Aircraft Tooling was typically built until the early 1990’s when Computer Aided Measurement Systems became user friendly enough for shop use. For decades prior to 1990 Tooling was a highly skilled profession requiring the “Toolmaker/Jig Builder” to have a detailed understanding of several types of measurement equipment and how to properly utilize them in order to fabricate the tooling to the tolerances required. The Toolmaker/Jig Builder would also be called upon to verify aircraft parts to tolerances of 0.030″, this might include taking measurements at specific locations on the “skin” of the aircraft by holding by hand optical scales that were read with two different measurement devices, a time consuming task.

In the late 80’s early 90’s Computer Aided Theodolites (CAT) became available and quickly became the “measurement device” of choice for building tooling. The CAT Systems allowed the Toolmaker/Jig Builder to measure all three dimensions from one setup for the first time ever. While these devices increased the time in which tooling could be fabricated, they still required a great deal of skill to obtain the precision and accuracy required for aircraft tooling. Verification of aircraft parts could now be accomplished by placing sticker targets on the aircraft and measuring them with at least two theodolites (they are a triangulation based system).

By the mid 90’s Laser Trackers made their appearance and as fast as the CAT System appeared it quickly became obsolete as the Laser Tracker could provide real time 3D Measurements, Laser Trackers were not as difficult to setup as the CAT system or earlier one dimensional measurement devices and were able to achieve a much higher degree of accuracy and quickly became the measurement device of choice all around the world for Tool Fabrication in not only aerospace but the automotive industry.

The arrival of the Laser Tracker with improved accuracy and the ability to measure 1000 points per second, also brought about big changes in tooling tolerances, suddenly, the +/- 0.010 inch tolerances of the past, were no longer acceptable, with many Engineers expecting that tooling could be built to the tolerance of the Laser Tracker (=/- 0.0020 inches)….Aircraft parts could now be measured by “scrubbing” the surface with the Laser Trackers spherical mounted reflector (SMR) collecting thousands of points very quickly and the ability to characterize surfaces faster and more accurately then ever before.

By the end of the 20th century Laser Scanners of all varieties became available and now millions of points could be collected very quickly without having to contact the surface of the part being measured.

So with all of the technology, the ability to measure faster, collect more data Tooling and Manufacturing have improved dramatically in the aircraft industry, however, the overall result may be even better if the Engineering requirements in some areas were a little more reasonable.

The ability to measure more accurately and precisely should not always equate to the “tightening up” of tolerances as has been seen worldwide, the reality is our measurements are more accurate then back in the 1D measurement device days. When tolerances are “tightened” in almost every situation it equates to a higher cost for the end product as more time is required to meet the new tolerance. The ability to measure millions of points on parts that were previously measured with hundreds of points does not always mean a better product as the data must be analyzed and deciphered, sometimes the “overload” of data can actually stop production as a decision is made on if the part is good or bad.

Having spent a lifetime working in measurement I have enjoyed being on the cutting edge of the new measurement technologies and would not trade it for another profession, but I do think back on the “old days” occasionally and wonder; how much data, is enough data? There are many airplanes and automobiles still operational today that were built using 1D measurement devices, while clearly not as accurate as today’s products, are we getting to the point of data overload? Are we expecting too much of our measurement systems given the limitations of manufacturing materials and environments?

Celebrate World Metrology Day (week)!

Get out there and MEASURE!

Thanks to Quality Digest for this humorous look at our often misunderstood profession!

BEYOND MEASUREMENT

Lean Metrology Tools for Rapid Inspection

Join Verisurf Software for this valuable webinar:Lean Metrology

Lean Metrology is the application of lean manufacturing best practices to inspection, tool building, reverse engineering, and assembly processes so as to minimize waste and optimize efficiency.

 REGISTER NOW:

Morning Session: May 13, 2014 from 9am-10am (PDT)

Afternoon Session: May 13, 2014 from 3pm to 4pm (PDT)

 Agenda:

  • Gain insight to the systemic benefits “lean metrology”
  • Learn about best practices you can apply immediately
  • See how automation can accelerate the inspection process
  • Learn about transformational trends in enterprise metrology
  • Witness a live demonstration of lean methods using Verisurf X
  • Get the opportunity to participate in a  Q&A session with a Verisurf Applications Engineer

About Verisurf Software

Verisurf Software, Inc. is a metrology software development company committed to delivering premier, field-proven computer-aided inspection and manufacturing solutions. Headquartered in Anaheim, California, we offer the most powerful, efficient and competitively priced Model Based Definition (MBD) software suite available today, bringing measurement metrology to the paperless factory.

Practical Metrology: Laser Trackers

Basic use and application of Laser Trackers in manufacturing from Quality Magazine.

Practical Metrology: Laser Trackers | 2013-05-03 | Quality Magazine.

NASCAR Race Teams utilizing Portable Metrology

Race Teams throughout the U.S. are now utilizing Portable Metrology systems to take advantage of building/inspecting to tighter tolerances. The ability to analyze in real time the conformance to specification has lead to more wins. This is a great article on where the technology is currently at: http://www.designworldonline.com/portable-metrology-pushes-race-teams-to-creative-engineering/#_

A Chain will be used to determine Winners/Losers in the NFL Playoffs

Here in the United States our Football is our american sport starting in late summer, we love our baseball, but come Football season the chants of “are you ready for some football” can be heard everywhere. What does that have to do with Metrology? Well, nothing….yet…..

Logo of the National Football League Playoffs,...
Logo of the National Football League Playoffs, 2011–present (Photo credit: Wikipedia)

In the American game of Football the goal is to move the ball down the field to the end zone, the team with the ball is given four chances (“plays”) to advance the ball 10 yards, if they advance it the minimum 10 yards they are rewarded with another four chances (plays) etc, until they reach the “end zone” where a touchdown and 7 points awaits. This ten yards is where Metrology should come in to play…..

Over the last several years the american game of football has used technology to improve the game by adding “instant replay” to determine if the Referee’s made the correct call or to determine if the ball was placed in the correct location on the field. In the National Football League (NFL) and in Colleges speakers have been added to the Quarterback’s helmet (Quarterback is the on field “General” for the Offensive unit) and to the Linebacker’s helmet (Linebacker is the on field “General” for the Defensive unit) so that their coaches can communicate with them so that they can make adjustments in real-time. The use of technologies in the players uniforms, shoes, helmets have improved safety and comfort of the players. Even the balls are kept at an exact temperature to ensure that when they are being kicked everything is “equal”, team benches are heated or cooled depending on the climate, technology is everywhere except…..

The aforementioned measurement of the 10 yards, what the ENTIRE games is based on that 10 yard increment. This 10 yard increment has the largest impact on a game of any one component, millions of dollars are won and lost based on that 10 yard increment, that 10 yards or 30 feet, carries a lot of weight. Jobs are won and lost based on that 10 yards, that 10 yards is everything….so how do you think it is measured in the year 2010 when the ability to measure 30 feet (9.1 meters) is down to the microns? Lasers? Total Stations? Some other sophisticated measurement system? NOPE, sorry the use of two poles and a chain….Sounds like Land Surveying dating as far back as history takes us right?

Measurement Method of the First Down

Several times during an american football game the “chain gang” will be called from the sideline, dragging out their poles and chains and the Referee will by hand “index” the pole to line of chalk, this is where the measurement is taken from, the chain is “stretched” to the tip of the football, to see if the “nose” of the ball exceeds the pole at the other end 10 yards (9.1 meters) away. This is how that all important measurement is taken, to those of us involved in the science of measurement the possibility for inaccurate measurements are endless, but yet, this is what american Football is based on, this has been the way since 1906.

When the Vice President of  officials from the National Football League was asked about this two years ago; he stated that he did not think it was perfectly accurate, and yet nearly two years later there is no advancement in how this crucial measurement is taken, why is that?

To be clear on the procedure that is used here is a quick synopsis;

On a first down, one end of the chains is placed along the sideline by one member of the seven-person chain gang — hired for game-day duty by the home teams — six feet from the field, supposedly even with the front tip of a football (“eyeballed”)  that will be snapped at least 25 yards away. When a play ends, an official estimates the spot, usually marking it with a foot and tossing the ball to another official to set for the next play. When a first down is too close to call, the chains are brought onto the field.

Sometimes the “drive” by the offensive team continues by an inch. Sometimes it ends by less.

There have been several attempts at innovating this process, however, it seems that the “ritual” of calling the markers onto the field, with the suspense it brings as the crowd quiets and watches the referee suddenly concerned with accuracy hold the ball still as the chains are stretched is what stops technology from intervening. The “american football gods” will say that the newer methods are unproven, and could lead to errors in the game, however, these same people would not want to hear how the human eye leads to errors when attempting to align an object 75 feet away.

Perhaps, someone reading this will come up with the system that will change the way the “first down” is measured!

Coordinate Measuring Machines: Here To Stay

This headline of this recent post by Quality Magazine (see link below) seems a bit humorous, as ‘CMM’s’ have been around for decades and do not seem to be going away any time soon. The number of CMM manufacturers and software developers does not seem to be shrinking. While being pushed by the more portable systems which have improved greatly in accuracy and precision there will always be a place for CMM’s in fast paced part inspection process or when the highest accuracy measurements are required.

 

CMM at work
CMM at work (Photo credit: ஃ முதல் அ வரை)

Test & Inspection: Coordinate Measuring Machines: Here To Stay – Feature Article – Quality.

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