To Let Blind Drivers "See" The Road
Students at Virginia Tech University have succeeded in breaking down another barrier for the disabled: Building a vehicle that allows the blind to drive.
Virginia Tech's Robotics and Mechanisms Laboratory developed a driver-assist system that uses laser range finders, an instant voice-command interface and a host of other cutting-edge technologies to guide blind drivers as they steer, brake and accelerate. The new system was put to good use last year at a summer camp where 20 blind and low-vision teens were able to take the wheel of a retrofitted dune buggy and navigate a course completely on their own.
"Although we are in the early stages of testing, the National Federation of the Blind -- which spurred the project -- considers the vehicle a major breakthrough for independent living of the visually impaired," said Dr. Dennis Hong, faculty adviser on the project.
Hong saw similarities between the technology used in Virginia Tech’s DARPA Urban Challenge, a military vehicle research and development program, and the requirements of the NFB’s Blind Driver Challenge.
"Our original goal was to simply make the vehicle accessible to the blind," noted Hong. "After speaking with the NFB, we decided to make a vehicle that could be independently operated by a blind driver."
High-Tech Equipment for Low-Vision Drivers
As expected, the buggy is packed with a host of equipment including a laser range finder, a Hall effect sensor, and a string potentiometer. "The laser range finder acts as the vehicle's eyes," said Hong. "It sends out a laser beam many times a second and measures the reflected signal to locate obstacles and lane markers such as curbs. The Hall effect sensor determines the vehicle speed and the string potentiometer measures the steering angle."
The system communicates with the driver via a series of non-visual interfaces. A tactile vest attached to the inside of the driver's seatbelt provides information to regulate speed and warn of obstacle proximity. An audio feedback system uses headphones to instruct where to turn and audible clicks tell the driver how sharply he is turning the wheel.
The system's performance can be measured by the smiles after campers took a turn behind the wheel. Kim Wenger was one of the student team leaders who participated in the event. "The Blind Driver Track was an interactive experience with hands-on activities that took the kids through the entire engineering design process," she said. "They learned how to change a tire, were able to get their hands on engine parts to observe how pistons operate, and how to be a responsible driver by learning road signs, giving directions, and taking a portion of an actual driving test."
The week culminated in driving time for the students using the vehicle in a parking lot. "This was the best part of the entire week because the students and mentors were truly appreciative and excited to drive, either for their first time or for the first time in many years," Wenger said. "They all felt a sense of freedom and independence."
"It was an amazing experience," enthused 15-year-old Ishaan Rostogi after his drive in July. "It's going to be great for all blind people across America." He said he now has hope that one day he might earn his driver's license -- something he never before imagined possible.
Reaching Beyond Sight
The technology developed for the Blind Driver Challenge is about more than just enabling the blind to drive. "Aside from giving the blind greater independence and a sense of empowerment, these blind-access technologies could have far-reaching benefits,” said Hong.
Examples of where these technologies might also be used include collision mitigation for automobiles, assisting elderly drivers, and even training new drivers. The system's non-visual aids could be used to enhance the safety and capability of airplane pilots, who operate in an environment saturated with visual information.
"Any task that requires fast and precise responses to a large amount of data in a short amount of time can be improved by the devices developed through the BDC," said Hong.
The next step for the Blind Driver Challenge project is to implement these technologies in an actual automobile. "All of these driver interfaces will be incorporated into this vehicle. The goal is to allow a blind driver to operate the vehicle independently in a real driving environment, including lane detection and object identification,” said Hong.