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Apparently ceramics innovations can keep you on your toes - and keep track of your fingers. Florida-based Sonavation Inc. recently announced what they claim to be “the biometrics industry’s thinnest, most durable and highly accurate fingerprint sensor for the wireless and smartcard markets.”

The sensor, dubbed the SonicSlide STS3000 (not to be confused with the infamous MST3000) is based on a ceramic MEMS piezoelectric transducer array. According to Sonavation, the 3 mm array is formed by pillars, “each one-tenth the thickness of a human hair. The pillars have a unique set of properties that enable them to mechanically oscillate when an electric field is applied. The oscillations then register in 256 shades of gray to form the images of ridges and valleys of the fingerprint.”

The entire set of components has been reduced to a single unit 35 mm in length by 14.5 mm wide with a thickness of only 0.25 mm

The company says that a big advantage of their system is that since it’s not a semiconductor, there are no problems associated with electrostatic discharge that have reportedly impaired the use of semiconductor-based sensors in personal electronics such as laptops and mobile phones.

According to its manufacturer, the STS3000 is capable of withstanding more than 10 million swipes and uses less power than comparable system, and uses an ultrasound system that supposedly provides greater accuracy of fingerprint images than available through DC or RF capacitive silicon sensors

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Kansas State University and Peregrine Semiconductors are demonstrating a battery-free technology that could improve embedded multi-sensor systems such as those that might be used to detect deterioration in busy bridge. “This type of radio technology may exist in your house, for instance if you have a temperature sensor outside that radios data to a display inside,” Kuhn said. “But those devices need to have their batteries changed. This radio doesn’t.” Peregrine Semiconductor says applications could include monitoring stress, temperature and pressure on bridges and other structures. K-State and Peregrine have already developed highly integrated, low power radio chips for NASA’s Jet Propulsion Laboratory using Peregrine’s UltraCMOS silicon-on-sapphire technology. The team has constructed a demonstration board using inexpensive solar cells to power the radio, but says they are also looking at piezoelectric, electrochemical and thermal energy approaches.

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Virginia Tech’s Center for Energy Harvesting Materials and Systems is hosting its 4th Annual Energy Harvesting Workshop Jan 28-29 in Blacksburg, VA. Energy harvesting refers to efforts to tap unused power from industrial machines, human activity, vehicles, vibrating structures and various other environment sources. Workshop organizers say the events bring together leading industries, national labs, defense agencies and NASA. This year, the meeting will focus on:

• Energy harvesting using piezoelectric, inductive, photovoltaic and thermoelectric devices
• Micro Batteries
• Structural health monitoring

What’s “structural health monitoring,” you ask, a new twist from life insurance companies? Nope. SHM is an emerging area of R&D that is centered on the development and use of sensing systems to track the health of structures such as bridges, buildings, dams, tunnels, pipelines, platforms or ships. Sounds interesting! The American Ceramics Society and its Electronics Division have endorsed the workshop. Complete information and registration is available online.

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Electric sensors cast in the pedal crank report biomechanical stress.

Smart parts - parts that can track themselves and predict their own breakdown - may soon be possible thanks to new ceramic materials and cast-metal manufacturing methods being developed at the Fraunhofer Institute in Bremen, Germany. According to an Institute press release, Fraunhofer scientists are developing a way to make light-metal parts “intelligent” by embedding electrical components and sensors into the parts during the casting stage of manufacturing.

Previously, this hadn’t been possible because electronic devices couldn’t withstand casting temperatures that reach 700°C or higher. The Fraunhofer team has reportedly overcome this problem by developing modifications to standard casting practices and designing new ceramic materials that can protect electronic equipment from extreme heat. As reported in the Sept. ‘08 edition of Materials World magazine, the Fraunhofer team is reluctant to reveal too many specifics until its research has been completed. What’s known, however, is that the Institute has tested its methods and materials through trials that successfully embedded piezoceramic sensors, light-emitting diodes, batteries, thermocouples and radio frequency identification tags into aluminum, magnesium and zinc.

Materials World says the Institute also has constructed and tested a prototype - a bicycle crank housing two piezosensors. The crank was installed on a bicycle displayed at Germany’s Hannover Messe technology expo this past April. Connected wirelessly and sending real-time reports to a computer, the sensors measured the amount of force exerted on the pedal by riders. By indicating how “evenly” each rider pedaled, the sensors were able to detect if riders experienced “inappropriate biomechanical stress during cycling.”

Health-monitoring is just one application that might result from the Fraunhofer Institute’s innovations. For instance, its press release suggests that now ”for the first time ever” manufacturers will be able to embed RFID transponders into cast parts and other products, enabling them to be “tracked, identified and protected against product piracy.” Sensors detecting aircraft material failure and unusual vibrations might also be used to prevent plane crashes, the release predicts.

Enthusiasm is not universal, however. In the Materials World article, Geoff Scamans of the U.K.’s Innoval Technology, voices concern. “With the [EU] End of Life Vehicles Directive, people in casting are worried about anything that interferes with sending scrap back. If there’s anything in the metals that has a residual impurity, that would be a problem,” he cautions. “Time will tell,” as the cliché says. Final reports are expected by the end of October.

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