Today’s mobile robots are severely limited by the energy capacity of the conventional batteries used to power their motors and actuators. But robots may soon take off, thanks to a team of engineers led by Michael Goldfarb and Eric Barth at Vanderbilt University. The researchers have built a novel robot actuator that runs on rocket power. For fuel, the simple, lightweight design uses liquid hydrogen peroxide stored at high pressure and mixed with a catalyst. The ensuing chemical reaction releases a flow of oxygen gas and hot steam that drives a piston. A robot arm hooked up to this rocket-propelled piston can repeatedly lift a 23-kilogram load five times longer than today’s best batteries and electric motors. Once developers have optimized both the hardware and the fuel, says Goldfarb, the rocket-powered actuator could pack 10 to 40 times the energy of a conventional actuator of similar size. That’s an improvement that would radically change the way robots are designed and used, according to Goldfarb. Vanderbilt has filed an application for a patent on the technology, and the actuator could be commercially available within the next three years.
A colorful little robot that resembles an overgrown computer mouse could give kids a chance to explore computer programming even before they know how to read. Users program the Curlybot without writing code. Just turn it on and scoot it across a flat surface. The roly-poly device records every movement exactly, and until it is turned off, it will repeat each movement, allowing children to see the effects of simple programs: how, for instance, a sequence of 90-degree turns can become a square or a short arc can become a circle or spiral. Developed by design firm Ideo’s Phil Frei while he was a graduate student at the MIT Media Lab, Curlybot is simple in design. Its brightly colored plastic shell hides two motors, each attached to a separate wheel, and the robot records its position 100 times each second. The frequent sampling allows for movement so precise, says Frei, that it looks eerily organic. Independent of Ideo, Frei is working to bring the newly patented toy to stores in about two years.
Talk about rescuing a conversation. Now you can preserve those snippets of cell phone calls you miss when, for example, you pull the phone away from your ear to punch a button. A system developed at Mitsubishi Electric Research Labs in Cambridge, MA, uses a proximity detector to sense when the phone is away from the ear and a memory buffer to record lost chatter. Return the phone to your ear and the playback kicks in, speeding slightly and deleting spaces between words until it catches up with the ongoing conversation. Because the system continuously records and stores the most recent 10 seconds, it can generate an instant replay if, say, a honking horn obliterates part of a discussion. Within the year, the Mitsubishi lab plans to license the technology for use in cell phones and traditional phone handsets, say its inventors, electrical engineers Paul Dietz and William Yerazunis.
A Bone to Pick
Technology being developed by Imaging Therapeutics, a medical-imaging company in San Mateo, CA, could enable early, accurate detection of osteoporosis, a disease that afflicts nearly 10 million U.S. residents and leads to 1.5 million fractures each year.
Early diagnosis can make a big difference in preventing fractures, but the best bone-density test now available requires equipment so expensive that few radiologists have it. In Imaging Therapeutics’ system, special algorithms reveal microscopic changes in bone architecture as captured in a digital image of a standard jaw x-ray. Such changes can appear in trabecular bone-a type of bone found in the hip and spine, as well as the jaw-even before loss of bone density is detectable. Imaging Therapeutics hopes that within two years it will be able to make its technology broadly available.
Making a hot blue flame from a liquid fuel (think camp stove or kerosene heater) requires bulky pressurized tanks or failure-prone pumps. But Richmond, CA-based Vapore has built a ceramic, solid-state “capillary pump” that vaporizes liquid fuel and ejects the gas rapidly enough to promote blue-flame combustion-with no accessory equipment. This could give rise to combustion appliances that are smaller, cheaper, safer, and more reliable than those now available. Prototypes of the device-as small as a dried pea and as big as a computer keyboard key-use capillary force to draw liquid fuel into a micrometer-scale, porous structure. Heat applied to the surface of the pump vaporizes the fuel into a gas collection area from which the fuel escapes at high velocity through an orifice. The U.S. Army is considering the technology for lightweight stoves, and Vapore is shopping it around for consumer products; it could also be used for noncombustion applications such as making gas vapor for fuel cells, says Vapore CEO Robert Lerner.
Universal Gene Therapy
A biotech startup in San Francisco is working on a way to transform gene therapy from a risky experiment into a routine treatment. Instead of inserting genes directly into patients, MandalMed researchers plan to transfer them into cultured cells, ensure the genes are working properly, and then implant the cells into patients. The general idea isn’t new, but MandalMed’s particular approach is. Rather than harvesting a patient’s cells, modifying them, and re-implanting them-a time-consuming process carried out to avoid immune rejection-the company hopes to establish collections of “immune silent” cells that would be accepted by any patient’s immune system. MandalMed has begun animal studies with cells that have been modified to treat spinal-cord injury and is testing a number of cell types from a variety of tissues for their ability to evade or suppress the immune system. The researchers’ goal is to tailor the cells for such applications as delivering therapeutic proteins to tumors, replacing proteins absent in genetic diseases including hemophilia, and treating multiple sclerosis, stroke, and Alzheimer’s disease.
That mysterious buzz you hear when you are driving your car can be an annoyance, but unexpected vibrations are often symptoms of deeper technical problems in machines such as aircraft engines or power transformers. That’s why physicist Philip Melese of SRI International in Menlo Park, CA, has developed a novel instrument that helps people pinpoint a wayward vibration by allowing them to “see” sound. The device contains optical sensors that detect the minuscule fluctuations in intensity that arise when light reflects off a vibrating surface. The sensors send their readings to a computer, which generates an acoustic map showing the vibration levels in each section of the object.
SRI has packaged these sensors into a “vibration camcorder,” which when pointed at a visible object will measure its vibrations. This beats existing measurement methods that require the tester to attach sensors directly onto the test object or to set up intricate laser systems. Several companies have expressed interest in the technology, which SRI hopes to see commercialized within two years.
The efficiency of conventional stacked-layer solar cells is compromised because some incoming light is reflected or lost as heat, instead of being absorbed and converted to electricity. Researchers at United Innovations in San Marcos, CA, have developed a new approach that captures incoming photons in a spherical cavity treated with a highly reflective coating and lined with multiple photovoltaic cells. Each cell is covered by a filter that transmits only those photons whose wavelengths match the cell’s highest sensitivity range; other photons are reflected within the cavity until they are absorbed by the proper cells. With support from the National Renewable Energy Laboratory of the U.S. Department of Energy, United Innovations has built a prototype and is testing the efficiency of the basketball-size cavity, which generates 1.5 kilowatts, says president Ugur Ortabasi. A computer model predicts that 48 percent of the captured solar energy will be converted into electricity. That would smash the industry record (34 percent), but to achieve it in practice may take several years.