Developments to Watch
Putting Real Feeling into Virtual Reality
SO FAR, WORKING THREE-DIMENSIONALLY ON A COMPUTER HAS BEEN MAINLY A TWO-SENSATION EXPERIENCE--images and sound. Only a few laboratory systems enable users to feel what's happening on the screen--and then from just a limited range of straight-line movements, such as forward and backward.
Now, researchers at Carnegie Mellon University's Robotics Institute have developed a prototype device that operates with six degrees of freedom, allowing more complicated movements. To provide a richer feel and a more realistic experience, CMU researchers Peter J. Berkelman and Ralph L. Hollis turned to magnetic levitation. The system's key component--something like a car's transmission--floats in magnetic fields. Unhampered by the mechanical pulleys and gears used in other sensory-feedback systems, Hollis' device can handle more complex movements and do so more sensitively.
With the control stick jutting from the top of a desk-top-high box holding the levitation system, a user can guide a virtual peg into a virtual hole and feel simulated forces, as well as friction, as it goes in. The technology could aid engineers in designing products. Hollis believes it will be especially valuable in training surgeons--letting them experience how it feels to cut into a body with a scalpel.EDITED BY ELLEN LICKINGReturn to top
A Cancer Drug without Crippling Side Effects?
CHEMOTHERAPY AND RADIATION ARE COMMONLY USED TO TREAT AGGRESSIVE CANCERS despite their debilitating side effects. But there is growing evidence that a drug called Maxamine--when used in combination with immune-system-boosting chemicals called cytokines--can double the survival time of patients with acute myelogenous leukemia (AML) and malignant melanoma without most of the crippling side effects. In fact, most of the patients were well enough to live at home during treatment, and many continued working. The drug, which is made by San Diego-based Maxim Pharmaceuticals Inc., is currently being used in 12 different countries to treat more than 800 patients in three separate phase III clinical trials. The company expects to file for Food & Drug Administration approval in mid-2000.
The drug mimics the action of the naturally occurring molecule histamine, and it works by enhancing the body's own immune response. Cancer cells usually release free radicals that destroy certain critical white blood cells of the immune system. But Maxamine blocks the production and release of these noxious compounds, thereby protecting the body's immune cells from damage. This means the cells are better able to mount a sustained attack on the tumor.
Because Maxamine appears to generally boost immune function, it could be an effective treatment for cancers other than melanoma and AML, as well as a remedy for viral diseases. Maxim Pharmaceuticals has also partnered with Amgen Inc. to develop Maxamine as a treatment for Hepatitis.EDITED BY ELLEN LICKINGReturn to top
Wee Rockets That Pack a Big Wallop
ON THE PRINCIPLE THAT GOOD THINGS COME IN SMALL PACKAGES, three engineers are building a rocket engine about the size of a dime that can generate at least 20 times as much thrust per unit weight as the space shuttle's main engine. Researchers Adam London, Alan H. Epstein, and Jack L. Kerrebrock, all from the Gas Turbine Laboratory of Massachusetts Institute of Technology, say that when a hundred of these ingenious microrockets are hooked together to create a palm-sized engine, they should be powerful enough to launch a 50-pound vehicle into space.
A prototype of the MIT team's tiny rockets, to be tested this spring, will be propelled by a mixture of gaseous methane and oxygen. But the final version, estimated to take three to five years to build, will run on liquid fuel. To accomplish this, the researchers are creating a miniature turbo-pump.
One advantage of the microrockets, the MIT researchers claim, is that they will cut down the amount of dead weight that's carried into space by at least half--which should considerably reduce the cost of launches. Someday soon, hundreds of the tiny rockets could be utilized to launch and maintain the positions of small scientific and communications satellites.EDITED BY ELLEN LICKINGReturn to top