Tuesday, November 10, 2015

Nondestructive Testing Inspection Services and Equipment Market in the Transportation Industry


Maintenance Requirements and Government Regulations Drive Growth
This research deliverable provides an analysis of the future global Nondestructive Testing (NDT) market in the transportation industry, particularly the impact and implications of Industry 4.0. An in-depth analysis of the two major market segments, the NDT inspection services market and the NDT equipment market, in the transportation industry is provided with a focus on the trends influencing the automotive, aerospace, and railway end-user verticals. The competitive landscape of the overall NDT market for the transportation industry has been clearly outlined. Global regions are segmented as Americas, EuropeAsia-Pacific, and the Middle East and Africa. The base year used for analysis is 2014, and the study period is 2011 to 2019.
Key Findings
– The Nondestructive Testing (NDT) market for the transportation industry is growing and is expected to hit $ Billion by 2019 growing at a compound annual growth rate (CAGR) of % between 2014 and 2019.
– The impact of the global economic downturn of 2009 affected the transportation industry until 2012, and recovery has been slow. But since 2012, the transportation industry has been showcasing high growth potential and there have been significant investments in new production facilities for the automotive industry as well as demand for more aircraft from airlines.
– The NDT inspection services market is expected to grow as the transportation industry
original equipment manufacturers (OEMs) outsource more NDT service requirements to NDT inspection services companies to leverage their expertise and to save time and costs.
– The maintenance, repair, and overhaul (MRO) requirements are especially high in the aerospace and railway industries compared to the automotive industry, which drives the
overall NDT market.
– The equipment manufacturers will push for adoption of advanced NDT technology, driven by transportation OEMs’ increasing focus on advanced materials because of compliance-driven regulations like CO2 emission regulations.
– China and India will gain focus from NDT market participants owing to their high growth potential.
CEO’s Perspective
1. The NDT market for the transportation industry is driven by the stringent regulations and changing requirements for inspection during manufacturing and maintenance.
2. Penetration of advanced materials used in lightweighting* during manufacturing will propel the overall NDT market, especially in the automotive industry.
3. In the automotive industry, cost considerations will be the key criterion to select NDT equipment manufacturers and also to outsource inspection to service providers.
4. Macroeconomic factors like rising global GDP, falling oil prices, and low interest rates will ensure that the NDT market grows in the aerospace industry because inspection is critical.
5. Maintenance of rail bogies, wheels axles, welds, and track will be the major areas of focus for the railway industry as automated inspection for quicker maintenance is the need of the hour.

NEW YORKNov. 9, 2015 /PRNewswire

Friday, November 6, 2015

High Demand Jobs Fuel NDT School Growth


American Institute of Nondestructive Testing Announces – NDT School in Baxter, MN has moved to a larger facility to handle the growing interest of high demand jobs in the NDT field.
Baxter, Minnesota (PRWEB) November 04, 2015
Nondestructive Testing (NDT) is one of the leading high demand jobs that is showing growth year over year. The American Institute of Nondestructive Testing is an NDT school located in Baxter, Minnesota, that has currently moved into a new 6400 sq ft building.
The American Institute of Nondestructive Testing was founded in May of 2013 by CEO Donald Booth. Their NDT training program consists of five months of online training followed by 24 days of intensive hands-on training at their Baxter, MN facility. Graduates will use radiographicultrasonicmagnetic particle, and visual inspection tools, among others, to learn the skills necessary to enter into the field of nondestructive testing. These skills will be used for inspection in a vast array of fields such as, aerospace, aviation, pipeline integrity, railroad, refineries, as well as, alternative energies such as nuclear and wind.
Since the grand opening of the NDT School, the American Institute of Nondestructive Testing has had a 95% employment placement. When asked why he believes his school has shown such great success, AINDT CEO Donald Booth replied, “The success of our school is largely due to the fact that skilled trades, more often than not, lead to high demand careers in a shorter time frame of education, which is what people are looking for in today’s economy. Our blended learning program allows for more individuals to be able to change careers without disrupting their lives completely by having to relocate or just drop everything to go back to school. People have lives, family, and commitments, we make it as easy as possible to get an education to move forward in life and get into a high demand career with great pay.”

PRWEB

Monday, October 26, 2015

International team launches unprecedented project to scan Egypt’s pyramids using infra-red technology


ELEANOR HALL: Scientists from Egypt, Canada, Japan and France have launched a project to probe Egypt’s largest pyramids using infrared scanning technology.
The project will begin next month, as Mandie Sami explains.
MANDIE SAMI: Egypt’s pyramids are thousands of years old.
While much has been discovered, scientist Matthieu Klein from Laval University in Canada says much more remains unknown.
And so he and an international team are using infrared technology to scan beneath the surface of Egypt’s pyramids to try to unlock those secrets.
MATTHIEU KLEIN (translated): We will take measurements by infrared thermography. These are measurements that are known in English as NDTnon-destructive testing. We won’t be touching the pyramids. We don’t move any of the blocks, nor do we make any holes. These are measurements that are taken from a distance.
MANDIE SAMI: The scanning will start next month south of Cairo at the so-called Bent Pyramid at Dashour, followed by the nearby Red Pyramid.
After that, Egypt’s two largest pyramids in Giza will be scanned.
Mr Klein says even though his team won’t be physically touching the pyramids, his optimistic that the infra-red method will yield results.
MATTHIEU KLEIN (translated): We hope that we will be able to display, if there are any cavities, ramps, tunnels or anything that might be under the surface. How deep can we detect things? Not very deep; we remain under the surface. We won’t be able to see completely through the pyramid, maybe a few metres at the maximum. But it could be that there are interesting things there, even a few metres deep, two or three blocks distance, under the surface.
MANDIE SAMI: Associate Professor Boyo Ockinga is an Egyptologist at Macquarie University in Sydney.
BOYO OCKINGA: I’ve not heard of this being used in archaeology before.
Ten years ago or so people tried to see whether there were any hidden chambers in the Great Pyramid in Giza by boring into a cavity that laid behind a wall and then sending in sort of a robot with cameras to sort of explore in these cavities, but you know, actually scanning the whole structure itself of course is another matter altogether and one can never know what can turn up there.
So this project here seems to be looking for evidence of chambers and so forth that can’t be detected in any way from outside where there is no hint of their existence from outside.
MANDIE SAMI: How exciting is it?
BOYO OCKINGA: Well I mean if they do find something it will be very interesting and very exciting indeed. And it’s a non-destructive way of finding out this information which is great; in the early days they used gun powder and explosives to try and blast their ways into the pyramids so obviously this is a much better way of doing it, and yes, we’ll be interested to see what comes of it.
MANDIE SAMI: What do you think the potential discovery is?
BOYO OCKINGA: We know that there were burial places for the kings. The question of course is, were their any hidden chambers that were fuelled with grave goods that were intentionally built in such a way that they wouldn’t be able to be accessed by anyone.
Now it’s just amazing, with the developments in science how these new methodologies can be applied to a science like archaeology, which opens up all sorts of new and exciting possibilities for retrieving information and interpreting it.

RNDT, Inc. is an ISO-17025 accredited commercial nondestructive testing laboratory located in Johnstown, Pennsylvania, that specializes in multiple nondestructive testing applications.

ABC News – ELEANOR HALL: That’s Associate Professor Boyo Ockinga, an Egyptologist at Macquarie University, ending Mandie Sami’s report.

Friday, October 23, 2015

Program Extends Missile System Shelf Life


As consumers, many items contain a “use by” or “best before” date. In the aviation and missile community, the same principle applies to the weaponry arsenal.
The Aviation and Missile Research, Development and Engineering Center, in conjunction with Program Executive Office for Missiles and Space and the Aviation and Missile Command, has a program designed to determine if missiles can be used past their initial shelf life. AMRDEC, one of six Research, Development and Engineering Command centers, executes this program within its Engineering Directorate.
“This program tests missiles to make sure they are still safe and reliable as the system ages,” Megan Shumate, AMRDEC general engineer, said. “All missiles have an initial shelf life from the date of manufacture. The Stockpile Reliability Program evaluates the missiles as they approach their shelf life expiration to see if we can extend the useful life of system to make the Army’s return on investment greater.”
The SRP is the sole mechanism for assuring the continued safety, reliability, performance and availability of the Army missile inventory per Army Regulations 702-6 and 740-1. AMRDEC, PEO MS and AMCOM collaborate to plan, execute and manage the SRP for all Army missile systems.
The SRP consists of component testing, flight testing and surveillance to collect data on the tactical stockpile. Additionally, users in the field submit a Missile Firing Data Report for all combat and training firings. These four sources provide an overall inventory analysis.
The component test is conducted annually through a statistical sample of missiles. All components are tested to see if they have degraded over time. It provides the best data for predicting continuing performance. Most of the SRP testing is conducted at Redstone Arsenal in partnership with Redstone Test Center.
“Every person involved in this process is a team,” James McGinnis, AI Signal Research Inc., said. “We provide support to RTC but we are all accountable to make sure the job gets done right.”
The flight test fires a statistically representative sample of the tactical inventory. Flight testing provides an indication on how well the missile performs in various temperatures and environments. It gives the SRP the best snapshot of current reliability.
The surveillance program consists of visual inspections and non-destructive testing. Visual inspections of missiles are conducted by a quality assurance specialist for ammunition surveillance for stockpiles worldwide. Some surveillance programs are conducted at depots while others are conducted across portable test equipment that can be deployed worldwide. This non-destructive test provides immediate identification and segregation of failing missiles to ensure readiness.
“As we continuously test and evaluate the system over its life cycle, the data and analyses are summarized in a report where we provide a shelf life extension recommendation for the missile system,” Shumate said. “We’ve been able to double the shelf life of most missile systems through the Stockpile Reliability Program. This provides a huge cost avoidance to the Army because they can maximize the useful life of their current inventories while avoiding having to purchase new missiles as often.”
Due to the success of SRP the average shelf life for missile systems has been extended from 7.9 to 22.6 years.
AMRDEC partnered with PEO and AMCOM to provide technical support to Foreign Military Sales customers and the Navy and Air Force through its Joint SRP and Field Surveillance Programs. The FSP and Joint SRP offer a multitude of benefits to joint servicemen and foreign partners.
A Joint SRP reduces the quantity of Army assets destroyed for component and flight test purposes. The partners share in the lessons learned and technology advances to improve missile reliability or maintenance.
“Our goal is to make sure that any missile is safe and reliable for the warfighter to use in tactical operations,” said Jimmy Kennamer, ASRI senior engineer and team lead. “When we identify and remove failing missiles, the warfighter can be confident that the weapons they are using will work when they need them.”
by Carlotta Maneice – AMRDEC Public Affairs

Monday, October 19, 2015

Bloodhound SSC Project — Success Depends on NDT and Condition Monitoring


BINDT’s support for the Bloodhound SSC (SuperSonic Car) land-speed record attempt project means that NDT News readers will be able to follow the progress of the Build Team as it assembles the most powerful land vehicle in history, and see how the success of the project depends to a large extent on the effective application of NDT and condition monitoring.
Bloodhound SSC will be powered by a Eurofighter Typhoon EJ200 jet engine and a NAMMO hybrid rocket, with a pump driven by a 750 bhp racing car engine. The car will be 13.5 meters long, weigh 6.5 tons empty (7.5 tons fully fuelled) and will accelerate from rest to 1000 mph and back to rest again in 120 seconds, covering 12 miles across the South African desert. With the current world land-speed record standing at 763 mph, set by Thrust SSC in 1997, also driven by Wing Commander Andy Green, this exceptional challenge is being led by former world land-speed record holder Richard Noble.
The project has attracted a world-class team of experts, with companies and individuals contributing their time and expertise to play a part in this extraordinary test of engineering.
Bloodhound SSC is also a significant educational initiative to showcase engineering and science, which currently involves more than 5,600 schools, nearly 50 universities and more than 250 further educational colleges. Two million primary and secondary students have access to Bloodhound SSC in their classrooms to learn about science, technology, engineering and math.
The car is a mix of car and aircraft technology, with the front half being a carbon fibre monocoque, like a racing car, and the back half comprising a metallic framework and panels, like an aircraft.
The whole car is an active NDT and condition monitoring experience. NDT is carried out as part of the manufacturing process and suppliers also carry it out on materials and components. Each component is tested using the most advanced and appropriate technology available. Every test run of the car will be continuously monitored and the condition of each critical part checked, over and over again.
One important part of the condition monitoring aspect of Bloodhound’s development is the use of embedded vision systems, which accept and record high-definition feeds from each of the 25 camera locations around the car. Each of the three compact Adlink EOS embedded vision systems on Bloodhound, supplied by Stemmer Imaging, provides a video stream for live transmission to the control centre.
The live video transmission has to be capable of reliable operation at speeds up to Bloodhound’s target of 1000 mph. Recent tests in the desert at Hakskeen Pan, South Africa, where video from the camera system installed on a Jaguar F-type vehicle was transmitted to a jet aircraft, have shown successful video and audio communication transmissions at closing speeds of up 650 mph, in readiness for the next phase, which is integration of the video system into Bloodhound itself.
The video data stream output will be connected to Bloodhound’s cockpit instrument panel computer and the vehicle’s radio modems via a router. The independent channels from each recorder can be simultaneously transmitted in real time and the cockpit instrument panel computer can also display one of these channels on one of the cockpit instrument displays.
The number of camera locations on Bloodhound has now increased to 25. There are five safety-critical locations and camera feeds from these will be used on all runs. These cover the instruments and controls, forward-facing and rear-facing fin tops, the rocket fuel connection hose and the rocket plume. Further developments in the wing camera mounting and optics are also underway to minimize distortion and the viewing angles and mountings for the cameras that will be monitoring the wheel/ground interface have been designed.
Small-scale rocket plume imaging tests carried out last year showed that the UV range of the spectrum provides useful information in addition to traditional color imaging of the rocket output. A JAI CB-140 GE-RA color camera and a JAI CM-140 GE-UV camera have now been selected to monitor the rocket on the car. The next stage of testing will be on the actual rocket to be used on Bloodhound. The rocket plume will be recorded in Finland using an Optronis high-speed camera and the UV camera in the near future.
“This really exciting project has thrown up numerous technical challenges, as was to be expected in an undertaking of this complexity,” Mark Williamson, director of corporate market development at Stemmer Imaging, said. “We continue to work closely with the Bloodhound engineering team to address each issue as it arises, and we are delighted that we are keeping up to pace with the overall development program.”
The Bloodhound SSC Show Car will be making a special guest appearance at this year’s Materials Testing Exhibition in Telford in September, an event not to be missed. In the meantime, see NDT News for news and updates on the progress of the Bloodhound SSC project and the role of NDT and CM in it.
Quality Magazine

Thursday, October 15, 2015

Key Elements of Magnetic Particle Testing


Magnetic particle examination is a very effective nondestructive examination method for the detection of surface and near surface discontinuities.
Charles J. Hellier, Quality Magazine – Magnetic Particle Testing (MT), one of the oldest and most reliable NDT methods, is often not given the recognition it deserves. It is considered a “non-glamorous” yet necessary process in the field of materials testing. And while there are significant variables that must be considered, the procedures for accomplishing the inspections, it is a relatively straightforward and dependable method—if it is performed with qualified personnel, using qualified procedures and proper equipment. And yet with its relative simplicity, abuses still occur. These will be discussed later.
The Beginning
There are a number of different accounts as to how it all began. There’s the story as to how S. H. Saxby in 1868 observed the presence of cracks in magnetized gun barrels by passing a magnetic compass over them. History does not tell us whether this technique actually caused the gun barrels to be rejects or repaired. Probably the most noted early observance of the potential use of magnetism as an NDT was by W. E. Hoke who filed a patent application on April 9, 1919, for the precision gage blocks he developed. It is generally thought that while the blocks were being precision surface ground, the small metal filings congregated at the location of fine cracks that apparently developed during the grinding process. It is generally accepted that MT truly began in the United States through the efforts of F. B. Doane, Carl Betz, and Taber de Forest. Early applications included railroad parts, metal castings and other ferromagnetic materials.
The Basics – How it works
To put it simply, the part is magnetized with a suitable magnetizing force, then small ferromagnetic particle are applied (dry or in a suspension) to the examination area. Magnetic flux leakage fields which occur at the location of discontinuities attract and hold the particles forming an indication. The indication is evaluated based on its size and shape to the acceptance criteria. This method is especially responsive to linear discontinuities such as cracks, nonmetallic inclusions (stringers), lack of fusion, and other conditions that cause a flux leakage. It will primarily detect those discontinuities at or very close to the surface in ferromagnetic materials.
Since the flux lines created with a magnetic field are directional, their orientation with the discontinuities must be considered. The maximum response occurs when the discontinuity is oriented at 90? to the direction of the flux line. While all of this may seem basic to the reader, some of the basics bear repeating to prevent errors that still occur with this relatively simple NDT method. These will be discussed later.
Equipment
The equipment used in MT inspection can be categorized into three groups:
Portable: Permanent Magnets, AC Yokes, and DC Prods. (See Figure #1 for an example of permanent magnets, Figure #2 for an articulated leg AC Yoke)
Stationary: Wet horizontal units and systems.
Accessories: Box demagnetizers, coils, field indicators, particles, light meters
Basic Procedure         
The prerequisite to achieving effective MT inspection is to have knowledge of the   following:
1. The requirements – codes, specifications, and contract requirements
2. The test objects to be inspected including materials type, shape, size, quantity, etc.
3. The available equipment and accessories.
4. The qualifications of the inspectors
The second step is to develop the procedure to be followed. This should be a complete, standalone, step-by-step set of instructions containing all of the essentials required to produce meaningful, reliable, and consistent test results. The technique and correct magnetizing current should be established and then the procedure should be qualified to confirm it will be appropriate for the parts to be inspected. This is a code/specification requirement in some cases.
In order to obtain meaningful results, the inspection process should include the following:
1. Evaluation of the surface condition. While this is not as critical as it is with penetrant testing, it is important to address any surface roughness that may cause confusion or be interpreted improperly as discontinuities. It’s better to address the surface condition before processing.
2. The surface should then be cleaned with an appropriate cleaner to remove any surface contaminants that may interfere with particle movement on the surface.
3. The part can then be magnetized using the technique established.
4. Evaluate.
5. The part should then be inspected with the flux lines at a direction approximately 90? to the initial test.Note: In some cases it may be necessary to demagnetize the part prior to inspecting at 90? if the residual magnetic field is higher than the field to be used.
6. Evaluate.
7. Complete the test report as required.
8. The part should then be thoroughly cleaned and if necessary, a rust preventative coating applied.
Techniques
There are a number of key choices to be considered when developing the most appropriate MT technique for a given application.
1. Continuous vs. Residual – The continuous technique (current is flowing while the particles are being applied) will provide the highest level of magnetism in the part and therefore produce the greatest flux leakage at the discontinuity site resulting in a more noticeable indication. The residual technique when used should be limited only to those materials with high retentivity.
2. Wet Suspension Particles vs. Dry Particles – In general, the wet suspension particles are used with stationary equipment such as the wet horizontal units and preferred for the smoother surfaces. These particles are also available in pressurized cans for use with portable equipment. However, the dry particles are most commonly used with the AC Yokes, DC Prods, and Permanent Magnets.
3. Visible vs. Fluorescent Particles – By far, the most sensitive (seeable) are the fluorescent particles. It is always advisable to use dry particles with colors that contrast best with the test surfaces, but with the fluorescent particles, the background is generally black or very dark purple when observing the test surface under a black light. The brilliant glow of the fluorescent particles against the dark background provides high contrast making the indication more visible
4. AC vs. DC – It is generally believed that parts magnetized with direct current will detect subsurface discontinuities. While it is true that this is the general understanding, MT should just be considered as an effective NDT method for the detection of surface and under ideal conditions, those that are slightly subsurface. The variables that determine just how deep under the surface a discontinuity can reliably be detected is influenced by its orientation, shape, size, vertical dimension, and the magnetic characteristics (permeability) of the test material. And with the use of DC there is always that possibility of arc burns where good contact between the test part and magnetizing equipment is not maintained.
Misunderstandings and Abuses
Even though MT is considered a “non-glamorous” and relatively simple NDT method to use, there are far too often procedure processing errors and shortcuts that can result in unreliable test results including:
1. Continuous
a. This technique requires the current (magnetizing force) to be applied to the part at the same time as the particles are applied. In some instances, the particles are applied after the current stops resulting in dependence on the weaker residual field. This is a more serious issue when the material has low retentivity.
2. Two directions
a. As mentioned in the procedure above, it is essential that the magnetic field be applied in at least two 90? opposing directions to assure detection of discontinuities regardless of orientation. There have been cases where the field is applied in one direction only which does not provide the assurance that all discontinuities will be detected.
3. Background Enhancement
a. One sure way to improve the contrast of the indications with the test surface is to apply a fast-drying white background lacquer to the surface prior to the application of dark particles. While this technique improves the visibility of the indication, some see it as an extra step which requires more time. We believe the extra time and small additional cost of the lacquer is justified in the benefits achieved.
4. Terminology
a. One of the major points of confusion in MT and in fact, all of NDT, is the improper use of the term “defect.” The generally accepted definition for “indication” is a response or evidence of a response disclosed through NDT that requires further evaluation to determine its full significance. Discontinuities are defined as flaws, imperfections or other conditions that are not part of the normal structure of the material. The term “defect” is continuously used improperly to describe a discontinuity and implies a defective condition which will essentially cause the part not to be used for its intended purpose. Some codes and standards do not always agree with this definition. To further illustrate this, one would not necessarily be reluctant to fly in an airplane with discontinuities since all planes have them, but no one would want to fly if the plane contained defects. It is hard to understand why there is so much reluctance to use the term defect properly.
Several Common Reference Codes, Standards, and Practices
•   ASME Section V, Article 7
•   ASTM E709 – Standard Guide for Magnetic Particle Testing
•   ASTM E1444 – Standard Practice for Magnetic Particle Testing
•   A275 – 15 Standard Practice for Magnetic Particle Examination of Steel Forgings
•   ASTM A966 / A966M – 15 Standard Practice for Magnetic Particle Testing
Benefits and Limitations of MT
Benefits
•   Very reliable for the detection of surface and slightly subsurface discontinuities
•   The equipment can be portable or automated
•   Indications appear directly on the surface
•   It’s possible to inspect through thin coatings such as paint
•   Surface preparation is not as critical compared to penetrant testing
•   Equipment is relatively inexpensive as compared to other NDT methods
•   Relatively easy to use and requires minimal amount of training
Limitations
•   The need for inspecting in two 90? opposing directions
•   Some metals, such as aluminum, magnesium, and most stainless steels, cannot be inspected
•   Discontinuity orientation with flux line direction must be considered
•   Demagnetization may be necessary
•   Possibility of arc strikes when inspecting with direct magnetization techniques
•   Can be time consuming depending on part size, quantity, configuration, etc.
Conclusions
In conclusion, magnetic particle examination is a very effective nondestructive examination method for the detection of surface and near surface discontinuities. It is widely used for a variety of structures during new construction and in-service applications. In general, it is a quick, low-cost inspection that is often the best NDE method for detecting surface and slightly subsurface discontinuities. NDT
Acknowledgment
Thanks to Martin Anderson, QA/NDT training manager, Global Technical Services, for his contributions to this article.
References
Magnetic Particle Inspection, A Practical Guide. David Lovejoy, Chapman & Hall, 1993
Handbook of Nondestructive Evaluation, Second Edition, Charles J. Hellier, McGraw-Hill, 2013.

Thursday, October 8, 2015

A Camera that Can See Through Walls


Humans cannot see through walls. Even out in the open, they can’t see too far on a foggy day. Ditto for search-and-rescue robots or self-driving cars with cameras for eyes. MIT researchers have hit upon a way to give those cameras an ability to see through walls and bad weather.
While most materials will stop visible light dead in its tracks, radio waves and microwaves with their longer wavelength can go straight through these objects. Still, conventional microwave or radar-detecting systems are huge, complex, and expensive and cannot be stand-ins for an automaton’s computer vision eyes.
Researchers from the Camera Culture Group at MIT have developed a simple camera-like architecture to create a novel radar for everyday objects. They describe their set-up in this week’s online edition of Science Reports.
 The new camera uses very low power microwaves – waves that are about 100,000 times weaker than what a microwave oven uses to cook food, and 100 times less powerful than the waves cellphones use for transmitting data.
It is not meant to be the next camera for consumers — the idea is to help with imaging in dangerous conditions, and to help with non-destructive testing.
First author of this paper, Gregory Charvat, a visiting research scientist at the MIT Media Lab, explains how the system works. To illuminate the scene, the camera uses a microwave-radiating flash. “When these pulses encounter an obstacle, they scatter off of the object being imaged, just as sunlight scatters off of everything to illuminate objects during the day,” he says.
A sensor, which acts like a lens, collects the microwaves that journey back to the device, processes them, and renders a high-resolution image.
Using microwaves is not without challenges. At larger wavelengths, surfaces appear mirror-like, making it hard to make sense of the image. The team’s solution was to use multiple sources of illumination and fuse the various images together using computational photography to get a more complete picture.
The researchers have demonstrated that the microwave camera can detect the presence of a plastic mannequin in free space, behind a dry wall, and behind plywood. Plastic is transparent to microwaves, but humans are made of water and are reflective to microwaves  – hence they wrapped the dummy in aluminum foil and made a “metal guy.”
metal1 metal2
Flat images of the metal guy are not all that the set-up can produce. It can capture 3-D images of objects.
Here too, the microwave source acts as a flash, transmitting microwaves to illuminate a metal ornament in one case, and the contents of a shipping box in another. Now the system uses a new trick – it acquires multiple camera images of the object from different illumination angles, and uses them to create 3-D images instead of flat pictures.
“It’s like a high-end professional camera that can take a series of still photos really fast,” says Charvat. The microwave camera does this in a fraction of a second. “When acquiring stills this quickly, at 200 picosecond time resolution, you can observe the microwaves propagating across the image scene at the speed of light,” he adds.
Here is one practical application. If there is a stack of unlabeled cardboard boxes in your garage you can use a microwave camera to get a 3-D image of what’s inside: one has books, another Christmas ornaments, and yet another has ceramic dishes. You’ll still need to open that box of books to look at individual titles though.
The wavelength of the microwaves decides the size and portability of the setup. “If we were to go from our current 10 GHz (3cm 
wavelength) down to 100 GHZ (3mm wavelength) then the entire system could be reduced in size by a factor of 10 which would bring it to a reasonable size for practical sensor applications,” the researcher says.
The device is now  a big circular dish 48 inches in diameter.  Its fairly large.  It can be a 10th of the size — 4.8 inches in diameter circular dish — if the wavelength is reduced to a 10th of what is used now. It is built from off-the-shelf parts and costs about $1,000 currently.
Within the next few years, higher-frequency radio-wave transceivers will become available for as cheap as a dollar, the researchers say. This development, they hope, will lead to a high-resolution, compact, and inexpensive microwave camera.
Such a camera can find use in rescue missions – searchers can look for survivors buried in rubble; firefighters can check if a burning building has an occupant. The multiflash aspect could help self-driving cars navigate better in abysmal weather. Another potential application is nondestructive evaluation of an object inside a cardboard shipping box.
Published in The Boston Globe by Vijee Venkatraman