Optics & Photonics News - November 2009

Amazing as it sounds, robotics researchers at Virginia Tech are developing optical technologies that will allow blind people to drive. Perhaps this shouldn’t be such a surprise, given current cars that automatically parallel park or warn a driver about veering out of a marked lane. The U.S. Defense Advanced Research Projects

Agency (DARPA), for example, has run several challenges that require vehicles to navigate unaided by a driver.

But the Virginia Tech Blind Driver Challenge has a different goal from autonomous vehicles. Dennis Hong, director of Virginia Tech’s Robotics and Mechanisms Laboratory (RoMeLa), explains, “We found out that the ultimate customers (the blind) want to drive the car, not be driven.” So the researchers focused more on how to convey a lot of information, in real time, nonvisually, to a driver.

An undergraduate group, led by mechanical engineering student Greg Jannaman, designed a vehicle that shares some architecture with the school’s autonomous vehicle developed for the DARPA Urban Challenge. Both projects involve similar challenges including perception, planning and system integration.

The dune-buggy-based test vehicle has a laser rangefinder on the front and three methods for providing data to the driver. First, a tactile vest inside the driver’s harness vibrates to indicate the presence and location of obstacles and the safe speed to drive. Second, drivers are guided through turns via an aural system on the steering column, which provides instructions to the driver through a pair of headphones. The number of clicks corresponds to the angle through which the car needs to turn. Third, the “AirPix”

DID YOU KNOW?

Yi Wu, University of North Carolina

Our cells are ridiculously complex, containing a stew of proteins that can be turned on and off in order to alter the cell’s behavior. Researchers at the Uni- versity of North Carolina recently described an optical technique that manipulates protein activity and location in living cells—which gives researchers a new tool for studying the fundamentals of protein function (Nature 461, 104). The technique makes use of a derivative of a protein called Rac1 that can be activated upon exposure to laser light; by manipulating the protein, researchers can directly influence cell motility.

By activating a protein called Rac (left), researchers caused the cell to protrude and summoned another protein to the area.

system provides gusts of air in a 2-D array near the user’s hands.

The team demonstrated a prototype this summer. On the closed-course driving tests, blind drivers outperformed sighted ones.

“I have no doubt that, with the technologies we are developing, blind drivers will someday be capable of safely operating a vehicle on the roads,” Jannaman says. The technology does require considerable further testing—and blind drivers will have to overcome social and legal barriers.

The work could also benefit elderly drivers with poor eyesight. Since the laser system operates well in low visibility, it could aid bad-weather driving. Haptic interface systems could also help sighted people to unload some information to other senses. For example, airplanes lean heavily on the pilot’s visual acuity. Jannaman says, “Spreading the high-bandwidth information from the highly saturated visual environment around to the other senses will greatly increase a pilot’s situational awareness.”

This school year, the RoMeLa team, led by Kimberly Wenger, is developing a high-bandwidth tactile map and incorporating lane detection into the vehicle.