Inventive Attainments

Grad student Daniel DiLorenzo has won the prestigious Jerome H. Lemelson Student Prize for several inventions, including mobile robots, a system for controlling brain swelling during surgery, a technology that helps paraplegics do some walking by stimulating their leg muscles, and an implantable microelectrode array that may help give a sense of touch to artificial limb users. DiLorenzo, enrolled in the Harvard-MIT Division of Health Sciences and Technology (HST), has a longstanding interest in engineering solutions to medical problems. He says his work on artificial limbs was spurred by reports half of amputees don’t like things about existing prostheses. A key complaint: users can’t tell how a limb is working solely by touch, meaning you have to keep an eye on your “hand” to be sure it’s working right. “Dan is a consummate inventor,” says Martha Gray, professor of electrical engineering and HST’s co-director. DiLorenzo is finishing work toward a PhD in mechanical engineering, an SM in management of technology, and (at Harvard) an MD degree. He’ll begin training in neurosurgery next fall. The Lemelson award goes annually to an MIT student who has exhibited stellar talents as an inventor.

Laser Magic

Makers of electronic chips must strive for a high level of quality control, and that means destroying some chips in order to ensure a given batch is put together right. An MIT chemist and his co-workers have now created a laser-based testing system that not only doesn’t hurt the chips but also provides an unprecedented level of accuracy. The system devised by Keith Nelson, professor of chemistry, gauges the thickness of the ultra-thin layers of metals — tungsten and copper, among others — used in fabricating chips. Nelson’s briefcase-sized system works by triggering pulsed-laser sound waves that traverse the layers, then are measured by separate laser light beams. The system can gauge the thickness of a metal film to a precision of a single atom’s width — roughly as much a fingernail grows in a hundredth of a second. It’s also easy to use: “You don’t need a PhD laser jock or computer scientist to get the numbers out,” says Nelson.

Smokestack Strategy

An MIT-China team that probed the potential for boosting efficiency at the nearly 500,000 boilers serving industrial plants around China has come up with some encouraging answers. The researchers found that two relatively simple steps — more training for plant operators, and new stack-gas monitoring equipment — could boost average efficiencies from 65 to 72 percent. If such changes were implemented at most or all the country’s industrial power plants, it would save roughly 75 million tons of coal annually. It would also slash emissions of carbon dioxide, a key gas linked to the global warming threat, by over 100 million tons a year. Kenneth Oye, associate professor of political science, and his MIT co-workers collaborated on the project with a group from the Taiyun Institute of Technology. Janos B┼Żer, MIT professor emeritus of chemical engineering, served as senior engineer and consultant.

Targeting Cancer

Radiation therapy calls for precise targeting to spare healthy tissues around a tumor. When your radiation-producing instrument is a behemoth the size of a small room, that’s a tall order. But an MIT group, working with counterparts from the Massachusetts General Hospital in Boston, has attained a precision better than what it takes to thread a needle. The challenge facing Steven Dubowsky, professor of mechanical engineering, was positioning the structure that bears the patient. The structure is located on a 12-foot-long robotic arm, part of MGH’s new system for beaming the sub-atomic particles called protons into a tumor. This means, says Dubowsky, that “the accuracy can be influenced by things like tiny construction errors or the bending of the arm due to the patient’s weight.” But the group developed a software program that can position the structure using only about 400 measurements, not the millions otherwise needed. The result is a positioning system accurate to less than one-fiftieth of an inch.