The drill being demonstrated. Photo: NASA/JPL

It's an invention that may eventually end up in the hands of every craftsman and orthopedic surgeon.

Scientists at NASA's Jet Propulsion Laboratory, Pasadena, CA, together with engineers from Cybersonics, Inc., Erie, PA, have developed an ultrasonic device that can drill and core very hard rocks and also has medical applications.

Potential medical uses include extracting pacemaker leads and the drilling necessary during surgical or diagnostic procedures involving the human skeletal structure. Future space missions could include drilling for samples using lightweight landers with robotic arms and small rovers that roam the surface of an asteroid or planet.

"The drill is an ultrasonic device that offers exciting new capabilities for space exploration in future NASA missions,¾ said Dr. Yoseph Bar-Cohen, who leads JPL's Nondestructive Evaluation and Advanced Actuator Technologies unit. „Besides the immediate benefits of the technology to NASA, it is paving the way for other unique ultrasonic mechanisms that are being developed in our laboratory and elsewhere. Such devices can be made to be small and lightweight, to consume little power and to exhibit a high standard of reliability."

"This technology can be miniaturized to fit in the palm of a hand," said Tom Peterson, president of Cybersonics, Inc. Cybersonics holds a patent for the Ultrasonic/Sonic Drill and Corer. "There are numerous commercial applications, especially in the medical field. We are very pleased with the progress in development and look forward to finding even more useful applications."

The drill is driven by piezoelectric actuators, which have only two moving parts but no gears or motors. Piezoelectrics are materials that change their shape under the application of an electrical field. The drill can be adapted easily to operations in a range of temperatures from extremely cold to very hot. Unlike conventional rotary drills, the drill can core even the hardest rocks, such as granite and basalt, without significant weight on the drilling bit.

The current demonstration unit weighs roughly 1.5 pounds (0.7 kilograms), which is sufficient to drill half-inch (12-millimeter) holes in granite using less than 10 watts of power. Comparable rotary drills usually require the application of 20-to-30 times greater pushing force and more than three times the power. The drill/coring bit does not require sharpening and its drilling speed does not decrease with time. There is no drill chatter, no drill walk on start-up, and the drill does not rotate. The bit can be guided by hand safely during operation. The drill can core holes in different cross-sections, such as square, round, or hexagon.

Bar-Cohen led the development team, which includes Drs. Benjamin Dolgin and Stewart Sherrit of JPL and the staff of Cybersonics, Inc. The technology was initially developed under a NASA Small Business Innovation Research (SBIR) Phase I contract that funded Cybersonics, Inc., and later received funding from the NASA TeleRobotic Intercenter Working Group. Currently, the development is funded by the NASA Exploration Program (Mars and Deep Space), and the Cybersonics effort is funded by an SBIR Phase II contract.