Tech Talk iconTech Talk

Internet Giants Disclose FISA Surveillance Requests For Customer Data

Technology giants such as Google, Microsoft and Yahoo have started disclosing U.S. government requests for customer information under a new agreement reached last month. But the first such reports on the controversial Foreign Intelligence Surveillance Act (FISA) orders remain limited in how much detail they reveal about the surveillance activities of the U.S. National Security Agency.

Read More

Amputee Successfully Feels Prosthetic Grip Strength Via Arm Electrodes

For decades, amputees have been able to open and close prosthetic hands by twitching muscles and activating a superficial electromyogram (sEMG), but they had no way of feeling what the prosthetic was encountering and little control over the strength of their grasping grip. It was a clunky, incomplete solution.

But recently, an amputee who allowed European researchers to plug electrodes into a bundle of his wrist nerves was able to control the strength of a prosthetic hand's grip and to distinguish the shapes and stiffness of three kinds of objects. The 30-day trial marks a success for one of several new experimental ways of giving amputees a better sense of touch and control over their prosthetics. A different group has conveyed sensations of temperature and vibrations by moving arm nerves into intact muscles of the chest, which act as biological amplifiers of the nerves' tiny signals. Another team tapped into nerves in the lower spine of cats to control their limbs. The Defense Advanced Research Projects Agency, is also seeking to improve sensation and control of its advanced prosthetics.

In the latest trial, appearing in Science Translational Medicine today, biomedical engineer Silvestro Micera of the Swiss Federal Institute of Technology in Lausanne (EPFL) and a large team surgically attached electrodes from a robotic hand to a 36-year-old volunteer's median and ulnar nerves. Those nerves carry sensations that correspond with the volunteer's index finger and thumb, and with his pinky finger and the edge of his hand, respectively. The volunteer controlled the prosthetic with small muscle movements detected by sEMG, a method that dates to the 1970s and measures electrical signals through the skin—unlike the electrodes attached to his nerves, sEMG is not invasive.

Read More

Vehicle-to-Vehicle Communications Tech Will Be Mandatory, say Feds

The National Highway Traffic Safety Administration (NHSTA) will soon propose rules for vehicle to vehicle (V2V) communications on U.S. roads, it announced yesterday. The agency is now finalizing a report on a 2012 trial with almost 3000 cars in Ann Arbor, Michigan, and will follow that report with draft rules that would "require V2V devices in new vehicles in a future year."

Read More

Road Salt Sensor for Better Highway Safety, Less Environmental Damage

Spreading salt on roadways is still the most cost-effective tool for preventing death, injury, and property damage from winter traffic accidents around the world.

In 2011, highway departments in the U.S. alone spread 19.6 million tons (1.8 billion kilograms) of salt on icy roads. They pay anywhere from $37 to $130 a ton for rock salt, so the total price tag is in the $1 billion to $2 billion range. But that’s just the beginning of the cost. Overall, for every dollar spent on the salt itself, there may be three dollars in damage—to roads, vehicles, and the environment, as salt eats away at bridge decks, corrodes rebar, blights neighboring vegetation, and drains off into surface and groundwater.

Spreaders lay down salt repeatedly during the icy season. Sometimes they may throw down more rock salt on areas that already carry far more than the optimum 15 grams per square meter; at other times, they may not drop enough. The Salt Institute says that roads departments could cut groundwater salt levels in half through careful controls.

Accurate, real-time measurement of the amount of residual salt on the pavement is vital to maintaining safety and reducing both direct costs and collateral mayhem. There are already sensors that collect water splashed back by a salt truck’s wheels and measure the changes in refractive index that accompany increasing salinity. These systems, first described a decade ago, work well…if the road is wet.

In the current issue of Sensors and Actuators B: Chemical, engineers at Spain’s Universidad Carlos III de Madrid demonstrate a simple, robust optical sensor that can strap onto a bumper and measure dry-pavement salt levels as the truck drives over dry pavement.

Salt glows orange in black light, and the brightness of the glow is proportional to the amount of salt present. More precisely, when illuminated at 273 nanometers, sodium chloride fluoresces at 610 nm (and also, though somewhat less usefully, at 310 nm).

The instrument the researchers describe includes an ultraviolet LED (much lower-powered than the lasers required by some other methods) and a photoreceptor, some filters for both emitter and receiver to tighten the ranges of stimulus and response, a power supply, A/D and D/A converters, a field programmable gate array (FPGA) to control the components and analyze the results, and a power supply that can modulate the LED output—all in a compact, rugged three-board package.

The researchers focused on salt’s 610 nm emission band: the wavelength is far enough away from the excitation wavelength to reduce backscatter effects, and this wavelength avoids the fluorescence of some of the biological material that collects on roads.

Engineers Marta Ruiz-Llata, Pedro Martín-Mateos, José R. López, and Pablo Acedo used a modulated UV LED to help them discriminate between reflections (from the UV and environmental sources) and the 610 nm fluorescence. It’s a balancing act: the slower the emitter fluctuation, the brighter the fluorescence, but the lower the ability to sort the fluorescence signal from reflections. (Fluorescence does decline very, very slightly with increasing temperature—but the change was small compared to other sources of variation, especially the naturally non-uniform distribution of salt broadcast over a hard surface.)

They adopted a 10 Hz excitation cycle (at this rate, the fluorescence persists for about 14 milliseconds). Tests showed that the device accurately measures the concentration of salt to within 10 percent over the critical range from 0 to 20 grams per square meter.

Photo: Tom Gralish/The Philadelphia Inquirer/AP Photo

Edited 5 February 2014: Instituting controls and best practices helps highway departments cut salt in groundwater in half, rather than halving overall salt usage. 

First Single-Molecule LED

Illustration: APS
Artist illustration of a single-molecule organic light-emitting diode

By coaxing light out of a single polymer molecule, researchers have made the world’s tiniest light-emitting diode. This work is part of an interdisciplinary effort to make molecular scale electronic devices, which hold the potential for creating smaller but more powerful and energy-efficient computers.

Guillaume Schull and his colleagues at the University of Strasbourg in France made the device with the conducting polymer polythiophene. They used a scanning tunneling microscope tip to locate and grab a single polythiophene molecule lying on a gold substrate. Then they pulled up the tip to suspend the molecule like a wire between the tip and the substrate.

The researchers report in the journal Physical Review Letters that when they applied a voltage across the molecule, they were able to measure a nanoampere-scale current passing through it and to record light emitted from it.

Conventional organic light-emitting diodes are semiconductors sandwiched between two electrodes. A voltage applied between the electrodes creates electrons and holes. When these two oppositely charged particles meet, photons are emitted.

The same thing happens here, except on a much tinier, single-molecule level. When the microscope tip had a large negative voltage, the researchers calculate that one photon was emitted for every 100 000 electrons that surged from the tip and into the molecule. The photon had a red wavelength. When the researchers flipped the voltage bias, the light emission was negligible.

IEEE Spectrum on Your Phone: New and Improved!

If you routinely visit IEEE Spectrum on your phone, you've probably noticed some big changes recently. If you've never tried looking at this site on your phone, now's the perfect time to start! We've made major overhauls to the the mobile view—here's a brief sample of what's new.

Read More

Google Highlights Value of Patents in Motorola Sale to Lenovo

Google has exited the smartphone manufacturing business and shored up Android's legal defenses in the smartphone patent wars in a single week. The technology giant sold off Motorola Mobility to Lenovo in a US $12.5-billion deal on Wednesday that allowed it to hold onto most of Motorola's patent portfolio.

Read More

Bitcoin Investors Urge Restraint at Regulatory Hearing

The New York State Department of Financial Services held its first of two public hearings yesterday to discuss the regulation of Bitcoin. The discussion comes at a turbulent time for the cryptocurrency, and the stakes are high for both investors betting on Bitcoin-based ventures and authorities seeking to prevent criminal operators from exploiting the privacy afforded by virtual currencies.

Read More

Tech Giants' NSA Deal Leaves Start-Ups in the Shadows

A group of U.S. technology giants has struck a deal with the Obama administration that allows the companies to disclose more details on customer data turned over to government agencies such as the National Security Agency (NSA) and the Federal Bureau of Investigation (FBI). But the fine print in the agreement leaves smaller companies such as start-ups with greater restrictions on when they can publicly reveal national security data requests for their users' data.

Read More

Modular Concepts at CES Hint at the Future of Mobile Computing

One of the highlights for us at CES is checking out concept products that will probably never see the light of day because they're just too crazy to give to consumers. You can think of them like pieces of designer clothing at a runway show: nobody actually wears that stuff, but it has the potential to influence the direction in which designs might be heading.

A trend that we noticed with concept products at CES this year was modularity: the idea that you shouldn't have to settle for a mobile device (like a cellphone or a tablet or a laptop) that only exists in a single form factor. We use these gadgets in all kinds of ways that they weren't really intended for (like, watching a movie on a cellphone or editing an Excel spreadsheet using a tablet's touchscreen)—wouldn't it be fantastic if we could dynamically reconfigure them to best fit our immediate needs? This is a significant hardware problem, and nobody has quite found the right way to solve it yet, but we saw some CES concepts that suggest a few different approaches that could eventually work.

Here, then are the modular highlights:

Read More
Advertisement

Tech Talk

IEEE Spectrum’s general technology blog, featuring news, analysis, and opinions about engineering, consumer electronics, and technology and society, from the editorial staff and freelance contributors.

Newsletter Sign Up

Sign up for the Tech Alert newsletter and receive ground-breaking technology and science news from IEEE Spectrum every Thursday.

Advertisement
Load More