Posts tagged tech
Articles and news from the latest research reports.
The Next Big Thing You Missed: 3-D Printing Promises Better Bionic Limbs for the War-Wounded
David Sengeh grew up in Sierra Leone during the African country’s decade-long civil war. The horribly bloody conflict was defined not just by the enormous death toll, but by the way rebel armies systematically severed the limbs of their enemies, leaving thousands of men, women, and children with missing arms and legs. Though the war ended more than a decade ago, Sengeh says, many victims are still struggling through life with artificial limbs that are too uncomfortable to wear.
But at the famed MIT Media Lab, the 27-year-old doctoral student is now using 3-D printing and advanced math to create a new kind of artificial limb he believes can significantly improve the lives of amputees in Sierra Leone and across the rest of the world. Sengeh relies on data-backed digital models to fashion prosthetics that he says better match the contours of the human body. And because these prosthetics are fabricated by 3-D printers, he says, they become far easier to produce.
The key problem with today’s prosthetics, Sengeh says, is that they don’t fit. Many people who have lost limbs — whether they’re Sierra Leone civilians or U.S. war vets — don’t wear their prostheses because the sockets aren’t tailored to their bodies. The tools needed to make well-fitting artificial limbs today are neither affordable nor widespread. “It does not matter how powerful your prosthetic ankle is,” Senghe said on Monday during a talk at TED, the global ideas conference being held this year in Vancouver, British Columbia. “If your prosthetic socket is uncomfortable, you will not use your leg.”
Low-Power Chips to Model a Billion Neurons
It’s a little sobering, actually. The average human brain packs a hundred billion or so neurons—connected by a quadrillion (1015) constantly changing synapses—into a space the size of a cantaloupe. It consumes a paltry 20 watts, much less than a typical incandescent lightbulb. But simulating this mess of wetware with traditional digital circuits would require a supercomputer that’s a good 1000 times as powerful as the best ones we have available today. And we’d need the output of an entire nuclear power plant to run it.
Fortunately, we don’t have to rely on traditional, power-hungry computers to get us there. Scattered around the world are at least half a dozen projects dedicated to building brain models using specialized analog circuits. Unlike the digital circuits in traditional computers, which could take weeks or even months to model a single second of brain operation, these analog circuits can model brain activity as fast as or even faster than it really occurs, and they consume a fraction of the power. But analog chips do have one serious drawback—they aren’t very programmable. The equations used to model the brain in an analog circuit are physically hardwired in a way that affects every detail of the design, right down to the placement of every analog adder and multiplier. This makes it hard to overhaul the model, something we’d have to do again and again because we still don’t know what level of biological detail we’ll need in order to mimic the way brains behave.
To help things along, my colleagues and I are building something a bit different: the first low-power, large-scale digital model of the brain. Dubbed SpiNNaker, for Spiking Neural Network Architecture, our machine looks a lot like a conventional parallel computer, but it boasts some significant changes to the way chips communicate. We expect it will let us model brain activity with speeds matching those of biological systems but with all the flexibility of a supercomputer.
Another team, led by Dharmendra Modha at IBM Almaden Research Center, in San Jose, Calif., works on supercomputer models of the cortex, the outer, information-processing layer of the brain, using simpler neuron models. In 2009, team members at IBM and Lawrence Livermore National Laboratory showed they could simulate the activity of 900 million neurons connected by 9 trillion synapses, more than are in a cat’s cortex. But as has been the case for all such models, its simulations were quite slow. The computer needed many minutes to model a second’s worth of brain activity.
One way to speed things up is by using custom-made analog circuits that directly mimic the operation of the brain. Traditional analog circuits—like the chips being developed by the BrainScaleS project at the Kirchhoff Institute for Physics, in Heidelberg, Germany—can run 10 000 times as fast as the corresponding parts of the brain. They’re also fabulously energy efficient. A digital logic circuit may need thousands of transistors to perform a multiplication, but analog circuits need only a few. When you break it down to the level of modeling the transmission of a single neural signal, these circuits consume about 0.001 percent as much energy as a supercomputer would need to perform the same task. Considering you’d need to perform that operation 10 quadrillion times a second, that translates into some significant energy savings. While a whole brain model built using today’s digital technology could easily consume more than US $10 billion a year in electricity, the power bill for a similar-scale analog system would likely come to less than $1 million.
Staff at the Seattle Children’s hospital have created the Cat Immersion Project — an audiovisual installation that brought thousands of virtual cats to a teenage cancer patient’s room.
16-year-old cancer patient Maga Barzallo Sockemtickem had spent seven months in the hospital in 2011 and had to return for more treatment in July this year. Because of her compromised immune system, she had to be isolated and was unable to see her beloved cat Merry.
Robot Learns to Pick the Sweetest, Ripest Strawberries
Richard Dudley imagines a world where strawberries grow in perfect rows and every day a robot army tastes their colors before harvesting the ripe ones. No, that isn’t LSD talking. The research scientist at the United Kingdom’s National Physical Laboratory is building a bot that uses multiple wavelengths of electromagnetic radiation to identify the sweetest, ripest fruit — then plucks it from the vine.
Disney researchers add sense of touch to augmented reality applications
Technology developed by Disney Research, Pittsburgh, makes it possible to change the feel of real-world surfaces and objects, including touch-screens, walls, furniture, wooden or plastic objects, without requiring users to wear special gloves or use force-feedback devices. Surfaces are not altered with actuators and require little if any instrumentation.
Instead, Disney researchers employ a newly discovered physical phenomenon called reverse electrovibration to create the illusion of changing textures as the user’s fingers sweep across a surface. A weak electrical signal, which can be applied imperceptibly anywhere on the user’s body, creates an oscillating electrical field around the user’s fingers that is responsible for the tactile feedback.
The technology, called REVEL, could be used to create “please touch” museum displays, add haptic feedback to games, apply texture to projected images on surfaces of any size and shape, provide customized directions on walls for people with visual disabilities and enhance other applications of augmented reality.
Is the singularity near, or is it already history?
The Singularity is Near is a hybrid of documentary and drama, co-directed by Kurzweil, that tries to explain the why and how of its title. Kurzweil’s alter ego, an animated character called Ramona, illustrates the evolutionary arc of thinking machines. She starts out as a primitive, choppy animation but gradually acquires consciousness.
As Ramona goes about her life, at one point seeing a clinical psychologist, her story is interwoven with documentary footage of Kurzweil explaining why the singularity is near. He tells us how machines are becoming atom-sized and how we are already implanting devices into the brains of people with Parkinson’s disease.
The Internet global network is a phenomenon of technological civilization, and its exceptional complexity surpasses anything mankind has ever created. In essence, what we are dealing with here is a huge quantity of utterly unstructured information. The Internet map is an attempt to look into the hidden structure of the network, fathom its colossal scale, and examine that which is impossible to understand from the bare figures of statistics.
Science fiction comes to life in Italian lab
At Italy’s Sant’Anna university, a bionic arm commanded by the human brain or a limb extension that allows rescuers to lift rubble after earthquakes are just some of the futuristic innovations in the pipeline.
“The idea is to get robots out of factories where they have shown their worth and to transform them into household machines which can live together with humans,” says Professor Paolo Dario, director of the college’s bio-robotics department.
The university in the historic town of Pisa in Tuscany is a veritable factory of ideas.
Researchers here are working on projects ranging from a robot that can come to your door to collect your recycling to tomatoes that slow the effects of ageing and plants that survive underwater to help flood-prone regions of the world.