The DSS Expo closed on Thursday afternoon with business still being done in some booths even as packing up began.
The number of exhibition visitors touring the hall this year set a record for DSS. And many were there to do business, exhibitors reported.
"We found a lot of qualifed leads," said Sam Wyman of StingRay Optics. "Being in the D.C. and Baltimore areas with so many military labs and government agencies is great -- they can visit us here on a day trip. We were mobbed on opening day."
Opgal thermal image
Qioptiq's Patrick Gray was also pleased with the location and the event. "This is the big opportunity of the year to see lots of customers in one spot," he said.
The DSS Expo included 454 companies and featured more than 130 product launches.
Applications on display included consumer items such as thermal-imaging attachments for smartphones (an example from Opgal at right; read more about the FLIR system in optics.org) with applications in home inspection to detect heat leaks, veterinary medicine to detect inflammation, security systems, and others, and numerous technologies with defense as well as consumer applications, such as high-performance cameras for deepwater exploration or precise long-distance imaging.
Total registered attendance for the conferences and exhibition was nearly 5,800 as the exhibition wrapped up, and several conferences continued through Friday.
The community is already looking ahead to coming back to Baltimore next year. Dates are 20-25 April 2015.
Sensors for fabrication of robotic skins
In the conference rooms ... Jeongsik Shin from the University of Texas Arlington discussed early results on "EHD printing as sensor fabrication technology for robotic skins" in the Sensors for Next-Generation Robotics conference, which is in its first year at the Sensing Technology and Applications symposium.
Robotic skin must demonstrate human-like performance and be readily tailored into various form factors while supporting a network of spatially distributed sensing points. Electrohydrodynamic (EHD) ink-jet printing enables the deposition of multiple sensor materials without the additional process steps and material waste generated by lithographic techniques.
Shin and his coworkers hope to utilize this technique in their work and presented their initial findings in this area. The team demonstrated the ability to print 20 micron lines using a continuous dispensing mode. Using a pulsed mode, they were able to print dot patterns as well.
The team experimented depositing several different types of sensor material including gold, zinc oxide and PEDOT:PSS on rigid substrates.
The work is now moving towards improving the EHD printing process and investigating performance on flexible substrates. Demonstrating sensor functionality on flexible materials is the next big milestone for this interesting work.
Rapid feedback in hostile chemical environments
Cavity-enhanced spectroscopy was the focus of a presentation given by Charles Harb of the University of New South Wales in his talk "Pulsed quantum cascade laser based hypertemporal real-time headspace measurements." The work represents a novel twist on traditional methods resulting in significant improvement in detection capability.
Real-time headspace analyzers are critical for rapid measurement and feedback in hostile chemical environments. The team looked to develop a system with a wide tuning range, and hence the ability to detect a wide range of materials, that could be deployed in the field and provide rapid feedback, high sensitivity, and robust operation.
To accomplish this, the team developed a variation on the traditional cavity ring-down spectroscopy system. Rather than operating in the time domain, the team looked in Fourier space and adopted a frequency domain approach when analyzing the cavity decay.
Exciting the cavity with amplitude modulated light and studying the relative attenuation of harmonic components allows for extraction of the decay constant. Given that power in the fundamental and second harmonic are highly correlated, studying the ratio of the two signals results in a highly stable signal.
The result is a system that can acquire more than 150,000 spectral data points across a spectral bandwidth of 1400 nanometers in less than 4 seconds at detection levels in the parts per billion range.
Data demonstrating detection of chemicals such as acetone, acetonitrile, nitromethane, and combinations of these substances at detection distances as large as one meter was presented as was real-time rapid scan data illustrating the hypertemporal capability of the system useful in understanding the flow patterns of the substance under study.
Another night of posters -- and networking
Thursday evening featured the second poster session of the week, and another opportunity to find new ideas and inspiration while networking with fellow attendees.
Wednesday 7 May
Sensing machines, enabled by light
Ludger Overmeyer, head of the Institute of Transport and Automation Technology at Leibniz University in Hannover, believes this is the century in which objects will start to feel -- and light will be the main medium to allow them to do so. In Wednesday morning's Sensing Technology and Applications plenary session titled "Planar Optotronic Systems," Overmeyer gave a comprehensive overview of the latest in the planar sensing technology that will make his prediction a reality.
Light provides a uniquely wide range of optimal signal parameters for sensing, including bandwidth and power. Overmeyer hopes to push optical sensing technology towards the trend in electronic technology, which started with large, clunky objects just a century ago and now mass produces micro- and nanoscale planar devices.
This technology integrates tailored polymer films with a variety of optical components, such as whispering gallery mode sensors and waveguide interferometers, to form planar optotronic sensors. These sensing films can be designed to detect an array of local changes, including chemical, thermal, and strain. Overmeyer believes the objects feeling their environment will be using these optotronic films to do so.
When 50 billion machines connect
William Ruh, Vice President and Corporate Officer at GE Global Software headquarters, asked the audience of Wednesday's plenary session, "What happens when 50 billion machines get connected?" During Ruh's presentation, "Emerging Industrial Internet," he brought to light the forthcoming transformation in the way machines communicate with one another and what that means for machine design, manufacturing, and functionality. "I think in the future we will see machines become self-healing," he said. "The power of this change is going to be driven a lot by sensing technology."
Ruh compares these changes with those seen in the music industry in the post-internet era. When billions of people became connected, the music itself didn't change, but the way it was distributed and consumed was revolutionized.
Likewise, it is the not the machine's purpose that will change, but its design, service, and operation. Sensing technology will allow these new machines to take part in planning, assessing, and reporting back.
As an early example, GE has developed dynamically adjustable wind turbines that can sense the local environment and account for changes, as well as functionality of neighboring turbines, increasing efficiency by 5%. As the industrial internet emerges, it is sure to revolutionize the needs of sensing applications and technology.
Sensing and imaging for food safety
In the Sensing for Agriculture and Food Quality and Safety conference, Moon Kim of the U.S. Agricultural Research Service spoke on "Hyperspectral fluorescence imaging coupled with multivariate image analysis techniques for contaminant screening of leafy greens"(9108-21). The work illustrates yet another practical application of hyperspectral imaging as workers in this field continue to find additional uses for this valuable technique.
Food, in particular agricultural products such as vegetables, can be contaminated with pathogens at any time during the growing, harvesting, packaging, and preparation process. Contamination from livestock, especially bovine contamination, is of particular concern since it can result in severe health consequences to consumers.
Moon described work using hyperspectral imaging techniques to monitor food. Recent increases in LED power in the UV and violet wavelengths makes fluorescent imaging possible.
Moon and his colleagues conducted studies demonstrating that a UVA wavelength works better than does a violet wavelength at detecting bovine contamination at high dilution levels (or low concentration rates). The scheme utilized a line scanning technique and multivariate image analysis to detect contamination diluted at 30:1 with distilled water and applied to spinach leaves.
Activity now is focused on improving a prototype conveyer system to enable front side and back side imaging, analysis and rejection of contaminated material.
Controlling drift in harsh conditions
Robert Okojie from NASA Glenn Research Center provided an invited talk in the MEMS for Harsh Environments session of the inaugural Sensors for Extreme Harsh Environments conference. Okojie spoke on "High-temperature SiC pressure sensors with low-offset voltage shift," demonstrating significant progress towards improving SiC sensor performance for use in harsh conditions (9113-9).
The use of silicon carbide (SiC) provides benefits in both static and dynamic sensing applications such as those found in energy exploration, engine ground testing, planetary atmosphere monitoring, and aircraft safety.
The issue with SiC sensors is that the zero pressure offset has been known to drift after calibration resulting in severe measurement errors. This drift is driven by thermodynamic and reaction kinetic effects within the sensor metallization. Okojie and his colleagues sought to implement a metallization scheme to stabilize this.
The team developed a metallization process using a titanium-tantalum silicide (Ti/TaSi2) stack followed by a tantalum-platinum (Ta/Pt) stack. Results presented from sensors utilizing this process demonstrated significant reduction in the zero pressure offset when running at 600C for 600 hours.
Both drift and full scale output error were reduced compared to results obtained with traditional SiC sensors. Similar enhancements in performance were seen during thermal cycling tests conducted with a maximum temperature of 500C over 500 hours.
Fabrication for high-temperature environments
Benjamin Griffin of Sandia National Labs also provided an invited talk, "Development of an aluminum nitride-silicon carbide material set for high-temperature sensor applications," in the Sensors for Extreme Harsh Environments conference (9113-11). The goal of the work done by Griffin and collaborators was to develop a new fabrication process to make sensors and transducers capable of performing well in high-temperature environments. Their results represent an important step forward in advancing the use of sensors in high-temperature environments.
Currently piezoelectric transducers operate up to 540C when air-cooled and nearly 1100C when water-cooled. The team looked to integrate aluminum nitride (AlN) with structural silicon carbide (SiC) on a polycrystalline SiC wafer with high temperature capable electrodes to enable higher temperature operation.
AlN is non-ferroelectric and demonstrates a piezoelectric response above 1150C so it is well-suited for high-temperature transducer applications. SiC is stable to temperatures above 2500C and is known for its high mechanical strength making it an ideal structural material for use at high temperatures.
Griffin described the process flow developed to integrate these materials coupled with high-temperature electrodes made from a titanium-titanium nitride (Ti/TiN) stack into devices built on SiC wafers. The team designed and built a micro-resonator and demonstrated that the device was functional to 953C.
Further work, such as migrating to nitrogen-doped silicon carbide (SiC:N) is planned to improve performance.
Self-assembly and programmable materials
In Wednesday afternoon's 3D printing session in Micro- and Nanotechnology Sensors, Systems, and Applications, Skylar Tibbits, director of MIT's Self-Assembly Lab, showed the audience innovative work building tangible, intuitive objects using the self-assembly principles found on the nanoscale (9083-45). The talk described advances in manufacturing techniques in the world of micro- and nanoscale technology, and their potential for as compared to svastly inferior manufacturing models on the human scale.
At the human scale, assembly is based on the connection of many parts, often across a wide range of sizes, in precise ways. Tibbits uses 3D printing capabilities to revolutionize the entire approach. As one example, structures are designed as a single part with precisely placed cuts or areas of expanding absorbent material. Once printed, agitating or submerging the system causes it to fold into its final form.
The agitation is the key step to this "4D printing," a method of injecting the energy needed to guide the system to in a new, and more favorable equilibrium state of the desired shape.
The agitation is just one possible way to introduce energy into the system. Structures can theoretically be designed to absorb any form of energy, including light. This process is exactly analogous to the way proteins fold. Tibbits and his team printed a life-size model of a protein strand that self-organized in a swimming pool.
The exercise demonstrates an additional potential in learning by creating tools to help build intuition of processes on the smallest scales by modeling them on scales we can see and touch. Rooted in principles of how energy and form relate, across all scales, the applications seem bounded only by the imagination.
DSS Expo: more ways to see what's out there
Polaris imaging equipment
Sensing, imaging, and display applications continued to draw visitors to the DSS Expo floor on Wednesday.
Among the displays by the exhibition's 454 exhibiting companies is Polaris Sensor Technologies' eTherm (for enhanced thermal) system, using both thermal and polarized infrared light for seeing at night. The mannequin at right wears the system's camera and viewing screen. (Read more about the system in optics.org.)
The Expo continues through mid-afternoon on Thursday, highlighted by more new product demonstrations and three New Technology displays:
FLIR ONE smartphone-based thermal imager
Johns Hopkins University Applied Physics Lab's "Robo Sally" high-dexterity anthropomorphic manipulation system
A distinguished career in service of community and country was recognized with the presentation of the DSS Lifetime Achievement Award to David Honey (above) of the Office of the Director of National Intelligence, by Defense + Security symposium chair David Whelan (Boeing Defense, Space, and Security) at Wednesday evening's banquet.
Honey's talk demonstrated Whelan's characterization of him as a leader and visionary, as Honey outlined technologies he sees as being important for development in the near term, and stressed the need for focus on developing a STEM-enabled workforce for the future. While exposure to STEM fields is important at all levels of education, Honey said, he agrees with experts who say that the middle-school years are particularly important. That is when many students begin to seriously consider what educational and vocational paths to pursue.
A ceremonial ribbon-cutting by Baltimore City Councilman Bill Cole and SPIE President Philip Stahl opened the exhibition Tuesday morning. Cole welcomed SPIE DSS attendees back to Baltimore, noting that the proximity of the city to federal labs and suppliers, including Baltimore's own strong technology and defense industry, make the city an ideal location for conferences on sensing technologies with applications in defense, security, the environmental, medicine, communications, and other areas.
More than 450 companies are in this year's exhibition.
Among the applications being shown, a robot named Robo-Sally (in video above) was winning friends. The prototype shook hands with an appropriately firm grip, handed over a pen, and did everything but dance while demonstrating near-human abilities via her modular prosthetic limbs and tele-operated feedback controls. In demonstrations, the robot replicated motions initiated by Senior Engingeer Kapil Katyal of the Applied Physics Laboratory at Johns Hopkins University.
Initiated with significant investment from DARPA, the new technology represents the first major upgrade in prosthetic limbs since World War II. A system of electrodes in nearby muscles picks up signals from the brain, enabling the amputee patient to activate the hand.
While functionality varies from person to person depending on when and where on the body the injury occurred, the installed prosthetic limb provides a high level of dexterity. The grip of can vary from being sensitive enough to pick an egg without breaking the shell, to being firm enough to grasp heavy objects.
Robo-Sally can be operated remotely as well, from up to a half mile away, fulfilling tasks such as bomb disposal or checking chemical spills. The technology is part of a larger Navy-sponsored program that includes unmanned ground vehicles to explode ordnance.
From a speaker series to help you explore career pathways, to panel discussions on careers in optics and photonics outside the academic world; the SPIE Career Booth, a Job Fair featuring top companies, and even a technical recruiter consultant to help you write the perfect resume, whether you're looking for a better job, re-entering the workforce or just starting out, SPIE DSS had ideas, advice, and helpful hints for every future employee.
During the Charting a Course in the Photonics Industry speaker series, Sergio Restaino, Naval Research Laboratory, talked about his career-path from astronomy instrumentation post-doc, to branch head at the Naval Research Lab.
Among conference presentations, Jun Yao, speaking on behalf of Charles Lieber from Harvard University, outlined the latest developments in nanowire assembly and use in construction of nanocomputing components during Tuesday morning's 1D Nanoelectronics session (9083-18) in the conference on Mico- and Nanotechnology Sensors, Sytems, and Applications.
Using a unique approach for alignment of the germanium and silicon combined cored/shelled wires, their "combing" method provides over 98% alignment of the wires to within 1°. One end of each nanowire is functionalized and anchored to a substrate window, while a combing substrate layer is dragged across the top surface, providing an aligning force parallel to the anchoring points.
The researchers use these wires as the building blocks to create full nanocircuits. By patterning anchoring sites, cross-bar nanowire arrays are arranged and their crossing points selectively functionalized to produce active transistor junctions.
The positions of these transistors in this crisscrossed pattern together make up the logic gates necessary for the desired circuit. Using tiles of these nanogates, Lieber's group has built a multitude of circuits including full-adders, full-subtractors, and flip-flops, to name a few.
As a logical future goal, these components are now being geared toward building nanoprocessors and a complete nanocomputer. A finite state machine (FSM) serves as a model for computation and using three of the nanocircuit tiles this device was first developed as a step in that direction.
These FSMs are not only robust, but also reprogrammable by changing transistor junction locations on the nanowire arrays. These new building blocks hold true potential for more complex structures in the world of computing.
Sensors for automation and robotics
Bingnan Wang of Mitsubishi Electric Research Labs presented on work done with colleague Jiang Long of the University of California, San Diego, in his talk "A metamaterial-inspired inductive-capacitive sensor" (9121-9). The presentation demonstrated the value of multisensor approaches and the value of metamaterials in addressing real-world challenges.
Proximity sensors play important roles in automation, robotics, and the automotive industry. Typically these sensors employ an inductive technology for sensing metals and a capacitive technology for sensing other materials including liquids, powders and pastes.
There are situations, though, when it would be beneficial to be able to detect both metallic and dielectric materials. One example would be robotic arms where distinguishing between materials could enhance handling schemes.
Metamaterials, materials engineered to achieve unique electromagnetic properties and which have the ability to respond to weak excitation, can be used for this dual purpose. Wang detailed the design of such a dual sensing scheme which consisted of spiral and coplanar sensing elements operating off resonance to achieve the desired performance, and he shared proof-of-concept results demonstrating detection of metals and dielectrics.
Compared to similar, commercially available sensing elements, the device offered comparable sensitivity while delivering the enhanced detection performance.
Improving maritime safety
Shanzeng Guo from Defence Research and Development Canada presented on a "Space-based detection of spoofing AIS signals using Doppler frequency" (9121-8). Guo's work provides a way to reduce the effect of spoofing, the deliberate transmitting of erroneous information, and improving maritime domain awareness and therefore, maritime safety and security.
Maritime domain awareness, basically situational awareness on the water, requires accurate and timely information on all naval activities for safety and security purposes. The automatic identification system (AIS) is a self-reporting system utilizing VHF radio to transmit vessel data including such information as location, speed, and identity.
Spoofing compromises AIS data integrity with safety and, potentially, security implications depending upon the intentions of those sending the spoofed signal.
Guo proposed a space-based AIS concept utilizing satellites equipped with AIS emitters. The scheme takes advantage of the fact that satellite speed far exceeds that of maritime vessels allowing the ships to be treated as stationary objects when the AIS signal operates at a sufficient frequency.
The Doppler shift of a single measurement can then be used to define a cone with the satellite at its vertex and whose intersection with the earth defines a trajectory on which the object is located. The intersection of multiple successive scans can then be used to pinpoint a vessel.
Tribute to a spectral remote sensing pioneer
Attendees in the conference on Algorithms and Technologies for Multispectral, Hyperspectral, and Ultraspectral Imagery XX observed a tribute to conference founder and longtime chair Sylvia Shen. The tribute was led by longtime colleague and co-chair Paul Lewis of the National Geospatial-Intelligence Agency.
Dr. Shen, a Distinguished Scientist at the Aerospace Corporation and an SPIE Fellow, died in September 2013. She was honored for her pioneering efforts in the application of mathematics to the field of spectral remote sensing that led to many important developments in the field.
Dr. Shen served as a chair of 34 SPIE conferences and 73 sessions. She was the author of more than 50 papers in technical journals and conference proceedings along with an equal number of US Government classified, unclassified, and proprietary publications.
Managing technology in a difficult environment: space
The challenge of how to appropriately manage technology development and introduction within a difficult economic environment is faced not only by industry but by government agencies as well, noted Troy Meink, Defense + Security plenary speaker. Meink demonstrated the tremendous benefit of space programs and stressed the need to more willingly embrace and manage risk to drive programs and enable success.
Meink, a member of the Senior Executive Service, Deputy Under Secretary of the Air Force for Space, and Director, Executive Agent for Space Staff, highlighted important applications in space and the challenges faced when implementing new technologies in the unique physical environment space presents.
The transition from laboratory to the field more challenging than it is for terrestrial applications. Once a system is deployed, it must be robust since opportunity for repair is limited -- for example, rebooting a computer on the International Space Station requires a spacewalk.
Optics are the most expensive part of space systems, and since cost is driven by weight, much effort is put into weight reduction.
The large expense associated with deploying satellites results in a risk-averse culture, extensive testing, and, hence, a slow transition from laboratory to field. To highlight this point, Meink noted that the technology used to get to space today, chemical propulsion, is what was used at the start of the space program.
The violent shaking that results from mounting a satellite to a rocket is a critical consideration driving satellite design to survive those first few minutes of flight. Once in space, the satellite is exposed to severe environmental conditions like high temperature variations and large magnetic fields. Given the cost, lifetime considerations are of prime importance, and so design must account for operation in these conditions.
Three areas guiding the current direction of space research and engineering are space situational awareness, earth observation, and laser communications.
Meink pointed out that today space is contested, competitive and congested. Over 60 countries now utilize space-based systems, and there are roughly 22,000 objects being tracked. Situational awareness is needed for insight into potential collisions. Radar is typically used for low orbit satellites while optical means, such as the Ground-Based Electro-Optical Deep Space Surveillance (GEODSS) system, are used to track deep-space objects.
Space also provides for a unique observation of Earth allowing satellites to collect and transmit data to observers to enable better informed decision-making. Commercial entities are now heavily involved in earth observation offering systems capable of sub-millimeter resolution.
On the military side, satellites equipped with the Advanced Responsive Tactically Effective Military Imaging Spectrometer (ARTEMIS) are capable of hyperspectral imaging and have been used to transfer data to field troop commanders. Laser communications, offering higher bandwidth and lower power than do competing technologies, continues to be an area of active research and interest.
Audience members (below) had several questions for Meink, particularly wondering how to incorporate a greater comfort level with risk into technology development.
In the conference rooms
Anupama Kaul, NSF and JPL
The conference week began in earnest early Monday, with speakers in dozens of conferences rooms. Among them:
2-DARE: graphene's potential
Anupama Kaul from the National Science Foundation started off the Micro- and Nanotechnology Sensor, Systems, and Applications conference with a review of the 2D materials emerging beyond graphene (9083-1), describing the highly promising possibilities of 2D systems for applications in electrical engineering as well as research.
In The Electronics, Photonics, and Magnetic Devices (EPMD) program she directs at the NSF and the recent Two-Dimensional Atomic-Layer Research and Engineering (2-DARE) initiative, efforts focus on multiple aspects of novel 2D structures including development, fundamental research, and applications integration.
Using little more than Scotch tape, a monolayer of graphite (the familiar material in the common pencil) was isolated and spawned the explosion of graphene research.
The 2D carbon structure is the thinnest material known, five times stronger than steel, and with no band gap is a good conductor. The properties discovered when this layer was separated from the bulk incited the desire for further research in 2D systems of already familiar materials.
The materials of this new focus include oxides, sulfides, and nitrides. Kaul highlighted some of the advancements in MoS2 research in particular.
In bulk, MoS2 is a semiconductor with an indirect band gap. In a monolayer, however, the highest energy in the valence band lines up with the minimum of the conduction band to form a direct band gap. Additionally, this band gap is strain sensitive, decreasing ~45 meV per % strain, opening up bio-sensing opportunities.
As these structures are by nature membranes, they allow for both nanoelectronic and flexible devise development. They can also be used as building blocks for 3D structures with atomically precise interfaces containing no out of plane dangling bonds, allowing for quantum tunneling and robust photoswitching devices.
As we approach 1 billion transistors per chip, Kaul pointed out, advances in these 2D systems provide huge potential in advancing micro- and nanoscale technology, by using common materials in novel ways.
Delayed SUCHI ready to launch
A suitcase-size satellite called SUCHI is now scheduled for launch in fall of 2014 on Kauai Island in Hawaii, after a delay for a year to fine-tune its intricate geological sensing technology, a team member said.
The delay was to allow more work on "a little of everything" said Sarah Crites, a doctoral candidate in geophysics at the University of Hawaii. "We need more testing of the whole spectrometer. We wanted to know more about what it would do."
On Monday, the SUCHI was undergoing tests to see how its components would survive the shaking involved in its launch. "I'm excited to have the vibration testing going on today. The SUCHI will be fastened to a table that is shaking like a satellite launch. This is the first time for these tests," Crites said.
SUCHI stands for Space Ultra-Compact Hyperspectral Imager for small satellites. The SUCHI is designed to study geological hazards like volcano eruptions and lava flows.
Crites' report was part of the conference Sensors and Systems for Space Applications.
Optics and the search for a lost airliner
The deep underwater search for the lost Malaysian airliner faces a host of problems, such as haze, turbidity scattering, and polarization. Speakers in sessions of the conference on Polarization: Measurement, Analysis and Remote Sensing gave the search very slim odds of success.
"It's dark. At just 40 meters, it's like night time," said Samuel Powell, Washington University in St. Louis (9099-1). "And it's incredibly blue. You lose all other color because water absorbs every wave length, except around 420 nanometers, which is blue."
Any search would face problems of scatter of photons bouncing in the water. Humans don't see polarized light but photography can capture it with proper equipment.
John van der Laan of the Optical Detection Lab at the College of Optical Sciences at the University of Arizona (OSC) offered some ideas from his research that could help the search (9099-7). One problem in a deep-sea search is that scattering of photons decreases contrast. "You can't see the difference between black and white," Van der Laan said. "It becomes harder to capture images and do sensing, the deeper you are searching."
If you are using optical means, as with a submarine, you would need to bring your own light, and that light would scatter widely from the turbidity of the water. "It would not go where you want it to go," said van der Laan's coauthor Shanalyn Kemme, a researcher at Sandia National Labs and adjunct professor at OSC.
Richard Vaia from the U.S. Air Force Research Lab focused on adaptive and metamaterials based electronic devices with his keynote talk, "Where art and technology meet: origami for 3D adaptive devices" (9083-7), demonstrating how he ancient Japanese art of origami is providing innovative methods of making the inflexible flexible in adaptive engineering.
With a main focus on aircraft morphing, Vaia presented adaptive wing structure developments for efficiency optimization of multiple flight maneuvers. The stationary wings of commercial planes are most efficient for high-altitude cruising, but poor for low altitudes, especially take-off and landing. Folding techniques provide a model where, said Vaia, "we can change the form of [the] system so the function follows." This includes changes of the wing's surface area by up to 50%. Origami allows researchers to add active panels to these folding structures, a particular challenge for circuits with typically rigid components.
Examples of applicable active panels in development include flexible InGaAs solar panels made by epitaxial liftoff techniques, a sample of which Vaia presented to the audience that fluttered freely with his hand motions. Their flexibility integrated into jet wings has already demonstrated an increase in flight endurance of 75%.
In-field solar chargers used by special-ops best highlighted the power of origami in these applications. The traditional tri-folded "wallet" model consists of a panel that opens up to 3 times its original surface area. Using instead a Miura-ori fold, a panel with the same starting dimensions as the wallet opens to have 15 times the area and power.
For optimization of interconnects across folds, active origami looks further to integrating flexible areas with the rigid areas in designing structures such as "origami actuators" as well as "snap-through" structures that have multiple eigenmodes of folding induced by different types of strain.
Sensors watch for greenhouse gas leaks
A laser-based sensing system for detecting gas leaks has been monitoring the millions of miles of natural gas pipelines in the United States for the last two decades, and a similar one has now been developed for application to the carbon dioxide pipelines that are used in extracting oil and natural gas.
Michael Frish of Physical Sciences (9101-15) described his company's tunable-diode-laser absorption-spectroscopy (TDLAS) pipeline-leak detectors, saying that about 2,500 are deployed in the field to detect natural gas leaks.
The detectors can be permanent or mobile, even deployed on UAVs, or "open-path" sensors that stand guard at intervals along a pipeline. When a leak is detected, these wireless, solar-powered sensors will generate an alert within one minute.
Frish said that the CO2-detecting TDLAS version, now being tested at various locations, is expected to become an important tool as the movement of carbon dioxide expands with carbon sequestration and increasing use of hydraulic fracturing, or fracking, in oil and natural gas extraction. In fact, last month former Secretary of Energy Steven Chu told a natural-gas processors event that lasers are a very important technology to that industry.
Rapid early testing for disease
The opening session of the conference on Sensing Technologies for Global Health, Military Medicine, and Environmental Monitoring included an invited talk from Daniel Malamud of New York University (9112-71) on "Rapid noninvasive tests for diagnostics of infectious diseases." Malamud described progress towards the development of noninvasive tests for early diagnosis and treatment of HIV, tuberculosis, and malaria.
Oral testing is an attractive alternative to blood testing since many blood targets are present in saliva, oral swabs are easy to use, the technique meets with higher subject acceptance, and the cost is often cheaper.
One challenge is the need for signal amplification. A second challenge is that the signal from oral testing doesn't faithfully track that from blood so a "saliva-plasma ratio," as Malamud described it, is needed.
Despite these challenges, antibodies, DNA/RNA, ions, drugs, and pathogens can all be detected through oral testing means. Furthermore, the oral technique lends itself to point-of-care (POC) use with the benefits of providing fast testing and diagnosis in addition to taking the device to the patient.
For HIV diagnosis, the goal is to combine screening and confirmatory testing and to complete the procedure within an hour; standard methods decouple the two tests separating them by weeks and lessening the probability that the patient will return for confirmatory testing. Great progress has been made towards the goal of reducing overall test time. Commercialization is underway and validation of the technology is a few years away.
For tuberculosis, existing tests give a high number of false positives to populations including individuals vaccinated with BCG (bacillus Calmette-Guérin) and those who live in endemic areas who have been exposed but not infected. Work done at NYU by Suman Laal and Susan Zolla-Pazner identified seven proteins expressed in the presence of tuberculosis. Malamud, Laal and Zolla-Pazner, along with additional business partners, are now commercializing this technology.
Malaria testing and diagnosis today typically involves blood smears and is time-consuming. Malamud and his collaborators are working towards a POC method using LAMP techniques and have designed a self-heating chip with an open architecture scheme which has been built into a cell phone form factor for POC use.
In the infrared
Fourteen vendors presented new products that will be on display in this week's exhibitionduring the Infrared Applications Thermosense Vendor Session, the first of the week's program of Industry Events. Above, Sam Wyman of StingRay Optics describes the company's new prodcuts. Vendors showcased products including thermal imaging devices, lowp-light imaging systems, and infrared cameras.
Solar for power -- and inspiration
SPIE Fellow Siva Sivananthan sees solar technology as a multifaceted opportunity, with benefits going far beyond energy generation into building communities and inspiring students. In a talk at Monday's Fellows luncheon, he illustrated several important advantages resulting from the work of solar research and applications deployment.
First of all, noted Sivananthan, Director of the Microphysics Laboratory at the University of Illinois at Chicago, development and transfer of the technology is helping to create a more efficient, sustainable energy source. Of commonly used energy sources, solar requires less time from installation to operation, is less expensive to implement than sources including nuclear and fossil fuels, and has a short recovery investment time.
At the same time, the potential for solar to add jobs goes beyond the manufacturing of solar cells and panels, and even beyond installation. Communities implementing solar also benefit from increases in jobs in the housing industry and services.
Solar also provides an excellent vehicle for outreach programs for all ages, Sivananthan said. He illustrated with examples from outreach supported by SPIE and done through InSPIRE (the Institute for Solar Photovoltaic Innovation, Research, and Edu-training, a nonprofit organization whose mission is to promote R&D, education and workforce training.
Before Sivananthan's talk, SPIE President Philip Stahl instroduced eight new Fellows of the Society. The distinguished members are among a total of 76 new Fellows named by SPIE in 2014, and include:
Brian Cullum, University of Maryland Baltimore County
Augustus Fountain, U.S. Army Edgewood Chemical Biological Center
SPIE DSS features a two-symposium perspective this year, with Defense + Security sessions complemented by the newly organized Sensing Technology + Applications symposium. All conferences are accessible for technical attendees. Presentations through Friday and the DSS Expo running Tuesday through Thursday. It promises to be a busy week!