Electronic signals ride the plasma wave
When a musician blows into a flute and pushes particles of air into a resonance cavity, audience members don't wait for the moving air particles to reach their ears. Instead, a pattern of sound waves quickly carries the music to the listeners. A similar use of plasma waves to carry information could create a whole new generation of devices or "electronic flutes" that are much faster than conventional computer chips. At least that's the belief of Michael Shur, the Roberts Professor of Solid State Electronics at Rensselaer Polytechnic Institute. At present, messages on computer chips are carried by electrons moving in a semiconductor. But if industry is to reach gigascale integrations (1 billion transistors crowded onto a single chip that operates at 1 billion cycles per second) in the next 10 years, these electron messengers need to travel much more quickly. Shur says that plasma waves could carry the data 10 times faster. He and a colleague have successfully built a primitive version of a detector that makes use of the waves. As Shur sees it, the first use of plasma-wave devices may be as extremely sensitive detectors for hard-to-find substances, such as environmental pollutants or minute quantities of explosives. E-mail [email protected].
One-step system cuts foam part-making steps
Millennium Petrochemicals Inc. has developed a polyethylene rotational-molding system the company says significantly reduces manufacturing steps for making foam parts. The new system eliminates the need and added costs for drop boxes in molds or a secondary foam application step. The technique can produce structures with a solid outer skin and a foam core or inner layer in one continuous molding cycle. In operation, the system blends three polyethylene resins: a compounded pellet for the foam layer and, for the outer skin, a blend of two polyethylene powders. Use of two powder resins for the skin ensures very smooth, pin-hole-free outer surfaces, according to the company. For single-wall foamed parts that require a smoother inner foam surface, a different foaming pellet is recommended. The three ingredients are blended directly in the mold. A dry colorant can be added to color the outer layer. Parts can have an outer skin thickness of 0.08 to 0.25 inch, and a foam layer or core of 0.25 to 6 inches with a density of 8 lb/ft3. FAX Henry D. Gudrian at (513) 530-6119.
Virtual endoscopy helps determine treatment feasibility
Scientists at Siemens Corporate Research have under development a virtual endoscopy system that could play a big role in helping physicians determine the feasibility of actual endoscopic procedures. In addition, the company says, the system could be used in diagnostic evaluation and physician training. For example, in one "virtual" application--bronchoscopy--a computer model of the trachea, bronchi, and lungs is created using actual computed tomographic (CT) images from a patient. Employing computer graphics, such as CAD/CAM, the CT images are used to re-create 3-D organ models in a computerized format. Similarly, using the dimensions of a real endoscope, a computer model of the camera is created with CAD/CAM, and a computer graphic is generated. "Using a computer mouse," Ali Bani-Hashemi, project manager notes, "a physician can then maneuver the virtual endoscope down the trachea and into the bronchi on the computer screen." If the endoscope can be placed within a few millimeters of the site of a suspected lesion or tumor, the physician knows an actual endoscopic procedure is feasible. E-mail [email protected].
Machine-vision system breaks speed barriers
Imaging Technology, Inc. has introduced the Prophecy 550, a machine-vision system that achieves inspection speeds in excess of 20,000 parts per minute--without relying on expensive, proprietary processors. The system consists of three major elements: the I-PCI high-performance, half-slot PCI bus-based frame grabber; the Sherlock 32 32-bit, Windows-based software applications; and an Intel Pentium host computer with MMX processor and Windows NT 4.0. The IC-PCI is said to be the fastest PCI-bus frame grabber on the market, providing 90+MC/sec sustained data transfer rates to the host computer's memory via an on-board, high-speed, dual-ported frame buffer of 2 or 4 MB. Users can configure the frame grabber for their specific cameras, eliminating the need to deal with the array of signals and timing variables required to accommodate diverse camera technology. "With IC-PCI, we can transfer an entire 640 x 480 x 8 camera image to the host computer's memory at 100MC/sec, or in about 4 ms," states Ned Lecky, Imaging Technology's director of machine vision software. In quantity, prices start at around $12,000. FAX (617) 275-9590.
New aerosols promise improved inhalation therapies
A dry aerosol mist, designed by a Pennsylvania State University/MIT-led team, has been shown in tests on rats to deliver medication significantly longer and more efficiently than currently used inhalation aerosols. David A. Edwards, associate professor of chemical engineering at Penn State, reports: "With additional research, the new aerosols can lead to improved treatments for asthma, cystic fibrosis, and other lung disorders. They also possess exciting potential as non-invasive delivery systems for medicines, such as insulin to treat diabetes, and for interferon, a cancer treatment." The aerosols consist of tiny, near invisible particles that are three to 10 times larger than those used currently, but weigh up to 90% less. They resemble a whiffle ball with medication inside. When the ball-like porous particles are inhaled, the medicine slowly seeps out in the lungs and either acts directly on the lung tissue or enters the blood stream as inhaled oxygen does. E-mail [email protected] .
'Smart' micromachine aids 'second silicon revolution'
The day when vehicles are made safer by machines no bigger than a thumbnail appears to be approaching more rapidly because of an agreement between Sandia National Laboratories and Analog Devices Inc., Woburn, MA. Sandia has licensed Analog--who makes airbag micromachine sensors--to commercialize the technology used to make Sandia's integrated micromachines. The integrated or "smart" machine combines microcircuits, sensors, and actuators on a single computer chip. Production of the "new generation" of small consumer and military devices based on the machines could include anti-tamper, anti-skid, and active-vibration control systems. Analog's airbag sensors use micromachines to signal when a vehicle is undergoing sufficiently rapid, sustained deceleration for the airbag to deploy. Because batches of silicon micromachines can be fabricated through manufacturing techniques already widely used to make integrated circuits, the devices are far cheaper than the complicated multi-metal constructions originally needed to signal an airbag to inflate. Rather than being made individually, micromachines can be fabricated quickly and cheaply by the thousands. E-mail [email protected] .
Technology eyes glaucoma in virtual reality
Machines now used to diagnose glaucoma, called visual-field perimeters, require a lot of space, are stationary, and uncomfortable for the patient. Also, the most popular models cost about $25,000, which means visual tests run in the neighborhood of $200 each. When John R. Kasha was diagnosed with glaucoma seven years ago, the electrical engineer figured there had to be a better way to test for the eye disease, he invented an alternative and formed Kasha Software Inc. in Falls Church, VA. With Kaha's system, the patient wears virtual-reality glasses to check the visual field. The glasses connect to an off-the-shelf laptop computer running Kasha's patented software. The system, costing about one-fourth the price of a current visual-field perimeter, is also portable. In clinical trials it has proved as accurate as the larger machines. Kasha's Visual Field System recently received FDA approval and will go on sale this summer. FAX (703) 532-6139.
Nanopowder synthesis speeds powder production rates
Materials Modification Inc. has developed a novel technology to synthesize nanopowders of iron and cobalt. Current techniques to produce the powders include: ball milling/mechanical attrition, laser ablation, vapor condensation, sputtering, chemical precipitation, aerosol, and induction plasma. Although each technique has its own advantage, one major disadvantage exists with all of these methods--production rates in the range of 1-2 g/hr. With the Materials Modification proprietary process, rates can be as high as 0.5-0.6 Kg/hr, with levels expected to reach 1 Kg/hr with certain modifications. To date, iron and cobalt nanopowders within the size range of 5-100 nm have been produced with a high surface area. The advantages, according to the company: production of both metallic and ceramic nanopowders; better control of particle size, distribution, and purity; ability to handle metallic, ceramic, organic, and inorganic precursors; thermomechanical process of components at significantly lower process conditions; and ability to handle both liquids and powders as precursors. Predicted applications: high-density magnetic storage materials, electronic materials, and nanoglass. FAX (703) 560-1372.
3-D/virtual reality system creates virtual Mars
As part of the Mars Pathfinder Mission, NASA used simulation application software to create an interactive, photo-realistic environment of Mars. Upon landing on Mars, the Pathfinder spacecraft released a single vehicle microrover--Sojourner--equipped with a pair of steroscopic cameras and other sensors. These instruments allowed the Sojourner to investigate the geology, surface morphology, rotational, and orbital dynamics of the "Red" Planet. The dual camera took stereoscopic images of Mars and sent them back to Mission Control, where they were converted into a 3-D Martian terrain geometry using a WorldToolKit-based application from SENSE8 Corp. The application then texture-mapped these images onto the 3-D terrain to create the virtual Martian environment. "WorldToolKit enables Mission control scientists to become 'virtual astronauts,'" proclaims Daryl Rasmussen, the telepresence researcher who heads the Mars Virtual Control Center at NASA's Ames Research Center. E-mail [email protected].