The University Record, August 13, 1997

GuideCane steers blind pedestrians around obstacles

Iwan Ulrich, a graduate student in the College of Engineering, tests the GuideCane. Ulrich built the cane designed by Johann Borenstein. Photo by Bob Kalmbach


By Sally Pobojewski
News and Information Services

It doesn't have fur. It won't fetch a ball. It runs on batteries, instead of dog food. But to the visually impaired, the GuideCane could give new meaning to the phrase "man's best friend."

Developed by research scientists in the College of Engineering's Mobile Robotics Laboratory, the GuideCane is a computerized, sonar-equipped navigation aid for the blind that detects obstacles in the user's path and automatically steers around them.

Johann Borenstein, research scientist in mechanical engineering and applied mechanics who invented the GuideCane, says it is easier to use than the traditional white cane, will be less expensive than a leader dog, and is more effective and convenient than other electronic navigation devices.

"A preliminary version of our working prototype for the GuideCane has been tested by visually impaired individuals and the reaction was extremely positive," Borenstein says. "But more development will be required before the device is ready for widespread commercial use."

The eight-pound GuideCane consists of a long handle with a thumb-operated joystick for direction control, an array of ultrasonic sensors and a small on-board computer mounted on a two-wheeled steering axle. Users push the GuideCane ahead of themselves with one hand. When the device's ultrasonic sensors detect an obstacle in its path, the computer automatically turns the wheels to steer around the obstacle and resume the original direction of travel.

"You feel the steering change as a direct physical force through the handle, which makes it easy to follow the GuideCane's path without any conscious effort," explains Iwan Ulrich, the graduate student who built the device. "Your body automatically follows the trajectory of the guide wheels just as a trailer follows a truck. Once the obstacle is cleared, the guide wheels resume their original direction."

Borenstein says that "after a brief adjustment period, most people will become so comfortable they will be able to navigate around obstacles at their normal walking speed. It's very intuitive to use. Unlike other navigation aids, there are no complicated acoustic signals to interpret and no extended training period required."

Borenstein and Ulrich have built a working prototype of the GuideCane and the U-M has applied for several patents related to the device. The U-M is seeking corporate partners to license the technology and assist with technical and commercial development of the GuideCane, so it can be made available for use by the visually impaired.

Funding to support the initial research and development of the prototype was provided by The Whitaker Foundation, a private non-profit organization that supports research and education in biomedical engineering.