Search

Got Metrology?

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!

Advertisements

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.

Computer Tomography for Measuring Components – FAI

The first article inspection report determines whether the corresponding tool can be released for production. For a hardware manufacturer, this extensive part evaluation used to take several days using conventional 3D measurement technology. Using computer tomography, the company was able to reduce the time required to a few hours.

Since 1952, Blum in Vorarlberg in Höchst has produced high quality hardware for high end furniture.  With about 5,000 employees worldwide, the company is a reliable partner for furniture manufacturers and aftermarket hardware dealers. In order to meet their customers’ high quality standards, this hardware manufacturer has used Werth multisensor coordinate measuring technology for many years. The measuring machines, which are used in great numbers, include models from the VideoCheck, Inspector, and TomoScope series. All measuring machine are equipped with the WinWerth software package for machine control and measurement data evaluation.

The company previously used conventional 3D measurement technology for first article inspection in order to release the final tool for production. This process often took several days. In order to significantly reduce the time required, they changed to coordinate measuring machines with tomography sensors for some time now. The measurement results are available in a few hours in the form of meaningful color-coded 3D presentations of deviations. In order to guarantee the measuring process capability of this measurement equipment, high quality technology is needed.

Integration in a coordinate measuring machine

The high requirements for mechanical and thermal stability for reliable computer tomography measurements can only be met by complete integration of this sensor into a coordinate measuring machine. In addition to the stable granite base, proven components and methods from coordinate measuring technology are used.

The TomoScope 200 combines computer tomography and multisensor coordinate measurement in one machine
The TomoScope 200 combines computer tomography and multisensor coordinate measurement in one machine

These include, for example, the guides and drives of standard measuring machines. High accuracy is achieved by intelligent reconstruction processes and a raster principle in imaging. This method allows measurements with increased resolution for determining the smallest features, even on large parts, and expands the measurement range of computer tomography. Traceable measurement results can be obtained by a calibration comparable to VDI/VDE 2617 part 13 using standards, such as spheres, gage blocks, or ballbar standards. The precision’s that are achieved thereby, in the form of specified maximum permissible error (MPE) are on the order of 4.5 μm or better. The application of these specifications to real measured objects, however, is possible only for “cooperative” parts. Variation in wall thicknesses of actual components, complex geometries, and different material properties influence the measurement results. This is caused by physical measurement deviations, known as artifacts, which arise due to X-rays penetration of the measured object. Artifact deviations depend heavily on the object geometry and the object material itself, and therefore cannot be corrected analytically with sufficient precision. However, because the errors are systematic, Werth AutoCorrection (patent pending) provides the ability to capture corresponding measurement points with high-precision optical or tactile sensors and correct errors in the tomography using these measurement points. In practice, the deviations between the tomography scan and a reference sensor are simply determined – only for dimensions with appropriately precise tolerances, of course – and any systematic errors are then fully automatically compensated by the software for all subsequent parts.

New Technology At a glance

The tomography process detects and measures all internal and external geometries of a part. The color-coded presentation of the deviations allows rapid evaluation of dimensional accuracy. Both the deviations from a CAD model, and the deviations between the current part and a master part (actual to actual comparison) can be visualized.

Plastic part from the Blumotion series left to to right: 3D point cloud, triangulated surface representation, and color-coded deviation plot relative to the CAD model)
Plastic part from the Blumotion series left to to right: 3D point cloud, triangulated surface representation, and color-coded deviation plot relative to the CAD model)

Simple standard measurements

In order to evaluate regular geometries with classical dimensioning, areas of the 3D point cloud are automatically assigned to the corresponding surfaces of the desired feature. This makes it very easy to determine dimensions, such as a diameter of a cylinder within the 3D point cloud.

Definition of cross sections in the 3D point cloud for determining dimensions in a 2D section
Definition of cross sections in the 3D point cloud for determining dimensions in a 2D section

In addition, cross sections can be freely defined within the measured CT point cloud. The sections are evaluated using 2D contour evaluation. This eliminates the need to cut and destroy components, saving time and money. Measurement times of many hours to a few days can thus be reduced to a few hours or even minutes.

 The increase in efficiency that can be achieved due to the particularly fast generation of first article  inspection reports enabled Blum to amortize its first measuring machine in about one year. Another machine was purchased just after the ROI of the first one.

Measurement using the 3D point cloud (left: patch selection using the CAD model, right: dimensional check of a cylinder)
Measurement using the 3D point cloud (left: patch selection using the CAD model, right: dimensional check of a cylinder)

 Although, classical optical and tactile measurement techniques will remain indispensable for rapid sample inspection during production, modern computer tomography provides new solutions.  It will continue to develop in the future.

About Werth Inc.

For over 50 years the name Werth has stood for the highest quality and precision in the field of dimensional measurement technology. The company has its headquarters in Giessen, in a region with a long tradition in the industry of precision mechanics and optics.
 
The company’s goal is to attain a high degree of customer satisfaction through worldclass technical solutions and unlimited user-orientation.
 
Through innovative developments in the field of high precision mechanics, image processing and software, Werth Messtechnik GmbH is now the world leader in the area of multisensor coordinate measurement technology. This is also reflected in a range of world firsts and patents.
A highly qualified team assures skill in terms of both advice and technical execution in all areas of the company, including development, construction, manufacturing, quality assurance and sales.
 
By active participation on standardization committees, we support product specifications and quality standards which promote competition.
Consistent quality assurance and acceptance to VDI/VDE 2617 and/or ISO 10360 are guarantees of the reliability, accuracy and comparability of the equipment.
 
Contact Info:
Werth, Inc.
8 Custom Drive
Old Saybrook, CT 06475
Phone 1.860.399.2445
http://www.werthinc.com

 

 

Automatic Vacuum Calibration System

Model: AVCS-3SDAVCS

AVCS-3SD is the only system on the market with FULLY AUTOMATIC pressure and process flow control, as well as data acquisition, from 1.3×10-3 to 1.3×10+5 Pa   (1×10-5 to 1000 Torr) with unsurpassed accuracy. The patent pending pressure control algorithm, integrated controls, calibration, and data analysis software will provide you with a cost effective approach to calibration of vacuum gauges that is NIST traceable, fast and repeatable. AVCS-3DS allows you to develop, store and recall multiple process recipes for each gauge or for a group of gauges and will consistently follow the selected calibration protocol today, tomorrow or 10 years later. A built in calibration process log file, in addition to data and process security, provide you with complete supervisory oversight of each process step. AVCS-3SD is fully compliant with ISO 3567. The system has 3 process modes and a service mode:

 Automatic mode – Auto selection of set points based on the number of set points per decade. Automatic processing from lowest to highest pressure.

 Semi-Automatic mode – Manual entry of set points prior to test. Automatic processing from lowest to highest pressure.

 Manual mode – Manual set point entry (one at a time) with automatic pressure and process control. Each consecutive set point can be set higher or lower than the previous one.

 Service Mode – Manual control of all valves and controllers. Beneficial for step by step system calibration and troubleshooting.

Contact Potomac Electric at www.potomacelectric.com for more details.

Hexagon Metrology Unveils WLS qFLASH White Light Measurement Solution

Optical Shop Floor System Expands Hexagon Metrology’s 3D Measurement Offering

NORTH KINGSTOWN, RI—January 13, 2014—Hexagon Metrology announced today the release of WLS qFLASH, a compact white light solution (WLS) that utilizes state-of-the-art blue light technology, for industrial measurement applications. The new Hexagon Metrology WLS qFLASH is a non-contact, stereo vision system used to quickly capture 3D measurements on the shop floor. The portable solution creates reports and digitizes acquired data on the spot for analysis or direct CAD comparison. Handheld or used on a mobile pedestal, the overall optical head design is smaller, lighter, and easier-to-handle in limited or confined industrial spaces. The new WLS qFLASH is ideal for measuring aerospace components, automotive plastic parts or interiors, closures, aluminum and metal castings, as well as medium sheet metal parts, molds and dies.WLS Flash On Pedestal LED on

The WLS qFLASH is wrapped in a rock-solid carbon fiber optical housing, and employs advanced blue LED high power illumination for reliable results. The system’s rapid image acquisition provides high throughput by utilizing patented stereo vision technology and 2D image processing to measure surfaces, closed features and edge lines. With low sensitivity to machinery vibration, industrial light or temperature changes, qFLASH enables manufacturers of small to medium size parts to measure surfaces and features in shop-floor environments. Hexagon Metrology’s patented stereo-vision technology allows the qFLASH to easily operate in production environments including stamping facilities and aircraft flight lines. The product is paired with Hexagon Metrology’s proprietary CoreView measurement software suite.

“The WLS qFLASH comes with state-of-the-art blue light technology based on the WLS400 product family. Its price point, small footprint, and light weight design make it a very attractive product”, said Amir Grinboim, Product Manager White Light & Automation for Hexagon Metrology Inc. “Together with the new CoreView 7.0 software, we are enhancing our white light solution offering to better support our customer base.”

The qFLASH stereo-vision technology enables fast image acquisition at an average of 10 milliseconds for constant measurement workflow. Shiny objects and surfaces can be measured without treatment. A random pattern is projected on a part, captured by the cameras, and analyzed at subpixel level, finding the differences in gray levels. Using the three cameras for triangulation, a 3D point cloud is reconstructed. Combined with 2D image analysis and propriety algorithms, the WLS qFLASH can extract closed features and edge points/lines without any post processing, such as STL generation, in a robust and repeatable process. This gives the qFLASH the unique ability to output inspection studies based on dense point cloud and 2D image analysis.

The product also includes a reverse engineering image acquisition mode which utilizes the sensor for both fast dimensional measurement and for reverse engineering. Among the new capabilities of CoreView 7.0 software is STL on-the-fly functionality to quickly and seamlessly generate high-quality data in the STL format for reverse engineering applications. This STL on-the-fly functionality is generated in the background so it will not slow down qFLASH’s data acquisition, enabling the qFLASH to maintain the WLS industry leading time from measurement to actionable data.

The WLS qFLASH is available immediately through Hexagon Metrology’s sales network and resellers.

About Hexagon Metrology

Hexagon Metrology offers a comprehensive range of products and services for all industrial metrology applications in sectors such as automotive, aerospace, energy and medical. We support our customers with actionable measurement information along the complete life cycle of a product – from development and design to production, assembly and final inspection.

With more than 20 production facilities and 70 Precision Centers for service and demonstrations, and a network of over 100 distribution partners on five continents, we empower our customers to fully control their manufacturing processes, enhancing the quality of products and increasing efficiency in manufacturing plants around the world.

Hexagon Metrology is part of Hexagon (Nordic exchange: HEXA B). Hexagon is a leading global provider of design, measurement and visualization technologies that enable customers to design, measure and position objects, and process and present data.

CMS Calls for Papers at the 30th Annual CMSC

The Coordinate Metrology Society (CMS) has issued its official Call for Papers for the 30th annual Coordinate Metrology Systems Conference (CMSC).

The association for measurement professionals around the globe seeks papers that explore the successful deployment of 3D coordinate measurement systems, industry best practices, scientific research and developments, and initiatives associated with portable metrology and related applications. The 2014 CMSC will be held in North Charleston, S.C., from July 21 – 25, 2014. The Coordinate Metrology Society convenes each year at the CMSC, a unique event designed for users of portable, high-precision measurement technology utilized to inspect manufactured and assembled components on the factory floor.

CMS community members and metrology professionals in manufacturing, scientific research, and academia are encouraged to submit abstracts for technical papers and presentations by the deadline of March 14, 2014. Guidelines for presentations and technical papers can be downloaded at 2014 CMSC Guidelines. The CMS Executive Committee peer-reviews each abstract for presentation at CMSC 2014. Notification of acceptance will occur on April 4, 2014. For more information about presenting a technical paper at CMSC 2014, contact Scott Sandwith, Technical Presentations Coordinator at presentations@cmsc.org. The CMS Executive Committee considers all technical papers presented at the CMSC, and selects the top papers for publication in the prestigious Journal of the CMSC.

At CMSC 2013, 26 expert presentations were delivered by industry leaders from The Boeing Co., NIST, NPL, FermiLab, API Services, University of Ontario Institute of Technology, Canada, Spirit Aerosystems, New River Kinematics, Lockheed Martin, Nuclear FiRST DTC, Rolls-Royce UTC, University of Manchester, The Nuclear AMRC, Variation Reduction Solutions Inc., Delcam, 3D Systems, LMI Technologies, 8 Tree, University of North Carolina, Dassault Systemes, ISRO Satellite Centre, ElectroImpact, East Coast Metrology, University of Bath, Coast Composites, and other companies and educational institutions covering technology, theory, and practice to advance the field of 3D metrology.

Blog at WordPress.com.

Up ↑

%d bloggers like this: