SignalCalc - AnalyzersNew Feature Focus

SignalStar - ControllersMultishaker Testing Web Seminar Summary

SignalForce - ShakersAker Solutions Chooses LE-358/DSA10-20K over low costcompetitor

Ecco Group selects GW-V400/DSA5-2K

Lumedyne Technologies selects GW-V100/DSA1-1K andGW-V20/PA300E

SignalForce Price List Notes

SubTrack - Underwater AcousticSystemsUnderwater Acoustic Systems

June 2011 | Volume 5 - Number 4

Welcome to the Insider The Data Physics Internal Newsletter

Data Physics bustled with activity this month. In earlyJune, we provided SignalStar Controller training at DPheadquarters in San Jose, California. We participated ina workshop on Spacecraft and Launch Vehicle DynamicEnvironments in El Segundo, CA on June 7-9 whereThomas Reilly presented results of testing related to thesix degree of freedom sine controller for NASA PlumBrook Station. In late June, Data Physics exhibited atthe Vibration Institute National Technical TrainingSymposium in San Antonio, Texas. The symposium isgeared toward rotating machinery, going hand in handwith our SignalCalc Turbo product. We also hosted twovery successful Web Seminars last week with over 100registrants each. Russell Zuppo presented theMultishaker Web Seminar while the SignalStar ProductManager Thomas Reilly was occupied in India withstrategic product demonstrations and training.SignalForce Product Manager Kevin McIntosh presentedthe Electrodynamic Shaker Web Seminar. Both WebSeminars had large audience participation with manyquestions from eager participants. The presentations,including the questions and answers will soon beavailable upon request.

In this issue, the SignalCalc section explores a new feature focus. The SignalStar section summarizes the Multishaker Web Seminardelivered on June 21st. The SignalForce section highlights several key sales and price list notes and for the first time we include a sectionon SubTrack, the Underwater Acoustic product line.

Renewal and growth continues with the addition of new hires. With increasing demand for SignalForce products, we have added four newemployees at the Corona facility. James Packard, Christen Smith, and Austin Montelius joined DP as electrical/electronic technicians whileDerek Builteman is filling the newly created position of Production Control Manager; please join us in welcoming all our new employees toData Physics.

With the expiration of the export denial to China on May 23, 2011, Data Physics has resumed sales of US made products in China. Whilethere is much work to do, the early indications are that sales into China will grow rapidly. With the substantial growth of the economy andthe increasing focus on quality, China has a voracious appetite for test instrumentation.

Data Physics is still looking to hire a few more good men and women and there are cash rewards for those who introduce successful newhires. Check the Careers page for openings. You are invited to refer suitable candidates with the promise of a monetary reward forsuccessful hiring of your referred candidates. The size of reward will vary between $250 and $1000 depending on the position. The first towin a reward is Russell Zuppo for introducing Jim Prange, who joined last month as the Regional Business Manager for the Central region.Russell wins $1000. To increase our multimedia presence, we launched two new videos on YouTube. The videos introduce the companyand spotlight SignalForce shakers. These can also be found on the Data Physics website. Please join our growing social media outlets suchas the YouTube channel, Facebook Page, LinkedIn group, and Twitter feed.

Inside this issue:

SignalCalc

Our Application Engineers offer a new feature focus about Transfer Function measurements.

SignalStar

Did you miss the Multishaker Web Seminar? A summary of the presentation is the focus of the SignalStar section this month.Multishaker testing has been growing in popularity over the past several years. Along with the increased use, more standards arebeing written around multishaker testing. The most notable standard to now include multishaker testing is the MIL-STD 810G,Method 527.

SignalForce

Key SignalForce sales include a LE-358/DSA10-20K shaker system purchased by the oil services giant Aker Solutions. Ecco Groupchose the Data Physics GW-V400HG/DSA5-2K shaker system for their testing and durability laboratory. Lumedyne Technologiespurchased two new shakers, a GW-V100/DSA1-1K shaker system and the GW-V20/PA300E vibration test system to test andcalibrate their MEMS accelerometers and energy harvesters.

SubTrack

Most of you may be unfamiliar with SubTrack, our Underwater Acoustic Systems product line. These products are sold exclusivelyto Navies of the world and have therefore been sold direct from the UK. Steve Potts, in addition to his Co-Managing Directorresponsibilities, carries the Product Manger responsibilities for SubTrack. An effort is underway to introduce these products to a keyUS customer and we are on the lookout for other opportunities in the US for these world class products.

NOTE: Outlook 2007 users may find the end of the Insider missing. Please use thelink below to the PDF file to view the missing articles.

View PDF Version of Insider

New Feature Focus

Transfer Functions – H1, H2 and Hv Techniques

Users can now display Tranfer Functions based on H2 estimate in addition to H1 estimate. H2 estimate can be enabled via a checkbox via the options button in the Measurement Panel (see picture below). Once enabled, H2 transfer functions can be displayed likeany other signal. H1 and H2 estimates are available in Transfer Function test type. H1, H2 and Hv estimates are available inMultiple Input Multiple Output (MIMO) test type.

H1 Technique:

H1 provides the best estimate in the presence of output noise and is typically used in situations where the output is noisy.

H1(f) transfer function is defined as: H1(f) = (Gxy(f))/(Gxx(f))

where Gxy(f) is the Cross Power Spectral Density average and Gxx(f) is the Auto Power Spectral Density average of the input.

H2 Technique:

H2 provides the best estimate in the presence of input noise and is typically used in situations where the input is noisy.

H2(f) transfer function is defined as: H2(f) = (Gyy(f))/(Gyx(f))

where Gyy(f) is the Auto Power Spectral Density average of the output and Gyx(f) is the Cross Power Spectral Density average.

Hv Technique:

Hv provides the best estimate in the presense of input and output noise and is typically used in situations where both input andoutput are noisy.

The solution for Hv(f) is found by the eigenvalue decomposition of the following Auto Power and Cross Power Spectrum averages.

Multishaker Testing Web Seminar Summary

In case you missed the Multishaker Testing Web Seminar on Tuesday, June 21st, here is a brief summary of the general overviewof multishaker vibration testing.

Multishaker testing has been growing in popularity over the past several years. This testing is done not only in the automotiveindustry, but across the board in the Aerospace, Defense, and even Electronics industries. Along with the increased use, morestandards are being written around multishaker testing. The most notable standard to now include multishaker testing is the MIL-STD 810G, Method 527.

NASA Plum Brook MDOF Shaker Installation

Team Cube Testing a Weapons Rack

There are three primary reasons to do multishaker testing: (1) better real-world reproduction of vibration, (2) large or massive testarticles, and (3) reductions in test time.

A more accurate simulation of the vibration seen in actual use enables engineers to better produce failures that they will see in thefield, and consequently have confidence in the survivability of products and equipment.

Extremely large test articles often pose problems for single shaker testing. The payload may require complicated or near impossiblefixtures to be tested with a single shaker. Very heavy test objects may even require more force than a single shaker can provide.

An additional benefit, that is increasingly being realized, is the reduction in test time that one sees from doing more than one linearaxis of motion at a time. Traditional development, qualification, and screening vibration testing has always been single axis testing.

Being able to better reproduce failures along with reducing test time makes simultaneous three degree of freedom an attractivealternative.

The current state of multishaker vibration control has now made it not only possible, but beneficial, to use two shakers instead of asingle large shaker when testing large payloads. In additional to the higher achievable force, a dual shaker provides less concernabout issues such as payload placement and upper end frequency performance. The flexibility provided by this arrangement alsomakes it possible to use the two shakers independently for component level testing at even higher frequencies.

3 DOF Shaker Arrangement

Dual Shaker SDOF Arrangement

Typical applications for multi shaker testing include earthquake testing and simulation, weapons system vibration qualification, seatvibration (both with and without a person in the seat), spacecraft and satellite qualification, automotive durability testing, automotivecomponent testing, squeak and rattle testing, and general purpose electronics testing.

The case of the electronics testing is an interesting one. Studies being undertaken at the Center for Advanced Life CycleEngineering (CALCE) are showing that 6 DOF shakers are better at exciting resonances and reproducing failures in certain types ofPCBs than repetitive shock testing (a.k.a. HALT). Over time, this could represent a significant shift in test methodology forelectronics testing.

6 DOF Shaker and Matrix Controller at CALCE

Although many shakers are available in off-the-shelf configurations, currently most multi degree of freedom shaker systems arecustom built per requirement. Considerations regarding the shaker type (electrodynamic vs. servo hydraulic), the table requirements,reaction mass requirements, and couplings are very important to the design of these systems. It is always recommended to workwith reputable professionals in building MDOF vibration test systems.

A proper multishaker vibration controller is required to accurately and effectively control multishaker tests. All degrees of freedom

that are not physically constrained should be controlled. For MDOF tests, a multishaker vibration controller is required because all ofthe actuators affect all of the test points in a rigid or flexible body. For multishaker single axis tests, additional issues such asimpedance mismatching between shakers, load imbalance, and structural dynamics make a true multishaker controller verynecessary for maintaining control without undergoing painstaking efforts of complex fixtures, couplings, and system matching.

Data Physics controllers use a pretest method for system identification to generate the first drive signal of a test. In multishakertesting, this pretest phase is more critical than in general single shaker tests, and requires careful evaluation. The FRF and multicoherence measurements provide valuable information to determine controllability of the test and preferred control points.

Multi Coherence Functions of 6 DOF Test at CALCE

Careful consideration of sensor location is required in both field data acquisition and lab simulation. As many users have found, amistake in location or direction can make running a test not possible. Additionally, it is important to be sure the data points arespatially located to adequately define the degrees of freedom in the test.

Whether working with electrodynamic or servo hydraulic shakers, the Data Physics SignalStar Matrix offers state-of-the-art vibrationcontrol capabilities which are unparalleled in performance and user interface. The controller uses the renowned Abacus hardwareplatform and is available from 2 to 16 output channels and hundreds of input channels. Matrix controllers are capable of control forrandom, sine, shock (including SRS), mixed-mode, and time waveform reproduction. Matrix controllers have successfully been usedon MAST tables, hexapods, Team Cubes, bi-axial earthquake simulators, tri-axial earth quake simulators, 3 DOF electrodynamicshakers, and a variety of SDOF and MDOF setups. Notably, the NASA Plum Brook shaker uses a Matrix controller to perform whatis arguably the most difficult vibration control task in the world.

Aker Solutions Chooses LE-358/DSA10-20K over low cost competitor

Aker Solutions Subsea Group in Houston, Texas selected Data Physics to be their supplier for an LE-358/DSA10-20K shakersystem with a 30" magnesium head expander. Aker Solutions is a leading global oil services company that provides engineering andconstruction services, technologies, product solutions, and field-life solutions for the oil and gas industry. Aker Solutions was able torealize the benefit of purchasing a durable solution for its testing needs rather than the low price, low quality shaker offered byDynamic Solutions.

Aker Solutions

Ecco Group selects GW-V400/DSA5-2K

Ecco Group, in Boise, Idaho, selected the Data Physics GW-V400HG/DSA5-2K shaker system for their testing and durabilitylaboratory. Ecco Group purchased a 10 inch cube fixture and an 18 inch round head expander, which will give them the flexibility totest all their products in their own laboratory. Ecco Group markets various safety products in various industries from back-up alarms,rear view CCTV systems and amber warning lights for commercial and industrial vehicles to siren amplifiers, speakers and red/bluewarning lights for the emergency services.

Ecco Group

Lumedyne Technologies selects GW-V100/DSA1-1K and GW-V20/PA300E

Lumedyne Technologies of San Diego, California has purchased two new shakers, a GW-V100/DSA1-1K shaker system with a 6inch x 6 inch unibase and the GW-V20/PA300E vibration test system to test and calibrate their MEMS accelerometers and energyharvesters. Lumedyne's AcXel accelerometer is the first MEMS accelerometer to utilize their patented electro-optical technology.This new optical approach to MEMS accelerometers allows performance not possible using traditional capacitive techniques.Lumedyne's technique has measured displacements of the proof-mass as small as 10e-15 meters (10 femto-meters), orapproximately the diameter of a proton.

Lumedyne's AcXel accelerometer

Lumedyne's V-Power technology converts ordinary vibrations into electricity. These vibrations can come from nearly any source,ranging from the vibration of a motor or even the sound of a person talking. The V-Power technology is a vibration energy harvesterthat has demonstrated RMS AC Power of 22 mW/cc per g of acceleration. This is equivalent to 17 Watts/Kilogram per g ofacceleration RMS AC Power. The V-Power vibration energy harvester is more than just an alternative to traditional batteries. The V-power vibration energy harvester can enable new applications such as wireless sensor networks that were previously not feasibleusing batteries or hardwiring.

Lumedyne’s V-Power Energy Harvester

SignalForce Price List Notes

NOTE: We have discovered an error in the price list for the LE-series water cooled shakers. Unfortunately, it seems we have beenoffering the VI (vertical isolation) option on the water cooled shakers. This is an error and has been corrected. The water cooledshakers are configured in the Low Frequency trunnions (LF), Rigid Trunnions (RT), or Monobase systems (MST). Please note thischange and do not continue to offer the LE-series water cooled shakers with the VI option.

Underwater Acoustic Systems

As well as making analyzers, controllers, and shakers, Data Physics UK also makes a range of underwater acoustic systems. Thesesystems are used to mimic the acoustic signature usually associated with a submarine, ship, or even a torpedo. They are usuallyused for testing and proving the performance of sonar systems on ships, submarines, helicopters, and maritime patrol aircraft.However, they can also be used for calibrating acoustic ranges and for training sonar operators. As an example, the towfish shownbelow was supplied to Japan for calibrating acoustic sensors deployed in Japanese waters.

Current Business

Most orders for underwater acoustic systems are based on our world leading model UW350 acoustic source. This is a wide bandprojector operating from frequencies as low as 20Hz to as high as 20kHz. Currently the UK has orders for 6 of these units, includingpower amplifiers and deployment cables, with an average value of $64k per order. Five of these systems are for customers in Chinaand one system is for Germany.

Other current orders include a contract from the Agency for Defense Development in Korea for the overhaul of two towfish and onetow cable that were originally manufactured in the UK in 1994. The ADD contract has a value around $230k.

The UK also has a contract to build a noise augmentation system for installation on a British Royal Navy submarine and repair workfor other submarine equipment. This is long standing work that the company has enjoyed for many years. The current value of thiswork is around $200k. Similar systems are deployed on submarines belonging to Spain and Canada.

Support services are provided for a system known as SAWCS (Submarine Acoustic Warfare System). This is an array oftransducers that are used to simulate the acoustic and machinery noise signature of a torpedo. The system was originallymanufactured by Data Physics UK with software provided by Data Physics USA. All of the hardware is installed in an ISO containerfor easy installation on ships. Since the contract was completed, the company has maintained the equipment. We also take it to seaand operate the equipment for Navy sea trials.

Data Physics UK now has acoustic systems installed in China, Japan, Taiwan, Korea, Australia, Canada, Spain, Turkey, Italy,Germany, Netherlands, Israel, Norway, France, and the UK.

Upcoming Events, Conferences, and Tradeshows

Data Physics will be hosting events and exhibiting SignalCalc Analyzers, SignalStar Controllers, and SignalForce Shakers at severalconferences and tradeshows in the next few months.

International Congress on Sound and Vibration in Rio de Janeiro, Brazil on July 10-14, 2011

Data Physics will join Brazilian based SignalWorks at the International Congress on Sound and Vibration (ICSV18) in Rio deJaneiro, Brazil, from July 10th to 14th, 2011. ICSV18 is one of the leading global events in the fields of acoustics and vibration.Companies, organizations, and individuals from around the world will be in attendance. The series includes presentations anddiscussions of the latest results and analysis concerning advanced theories, technologies, and applications related to sound andvibration. The gathering in Brazil is the annual premier event organized by the International Institute of Acoustics and Vibration(IIAV).

The 25th Institute of Noise Control Engineering (NOISE-CON) in Portland, Oregon on July 25-27, 2011

NOISE-CON 2011 will take place simultaneously with the meeting of the Transportation Research Board Committee onTransportation-Related Noise and Vibration. The technical program for the joint conference will provide an opportunity for public andprivate organizations to share technical information on noise and vibration topics associated with high speed rail, light rail systems,highway surface, and tire noise and aircraft noise. The technical program will include papers in areas such as Experience withMeasuring and Modeling of Wind Turbine Noise, Control of Noise Both Interior and Exterior to Buildings, Industrial NoiseMeasurement and Control, Product Noise Measurement and Control, Noise Measurement Equipment and Techniques, StructuralNoise Transmission, and Control and Community Noise Measurement and Control.

Demonstrations used throughout the course highlight specific application issues. Students learn how to solve real-world problemsthat are often encountered while running tests. In addition to learning how to obtain optimum performance from a shaker andcontroller, students will also learn to diagnose problems with transducers, fixtures, and the shaker-amplifier system.

Contributors

SignalCalc Contributor: Kalyan Vitta, Application EngineerSignalCalc & SignalStar: Thomas Reilly, Product ManagerSignalStar Contributor: Russell Zuppo, Marketing ManagerSignalForce: Kevin McIntosh, Product ManagerSignalTrack: Steven Potts, UK Co-Managing DirectorManaging Editor: Sri Welaratna, PhD, President and CEOEditor: Per Lindberg, VP, Marketing and SalesEditor: Bourke MacDonald, Marketing Communications Specialist