Driving blind

In an effort to promote the capabilities of the blind and to inspire innovation in the development of blind access technologies, the US National Federation of the Blind proposed a challenge to design a system capable of providing the blind with the ability to drive. This challenge was then taken up by the Robotics and Mechanisms Laboratory at Virginia Tech. In two semesters and with nine undergraduate students and $3,000 USD in seed funding, a blind driver would be expected to safely perform the three fundamental driving tasks: navigate through a curved driving course defined by a single lane of traffic cones, regulate speed within a predefined limit, and exhibit sufficient emergency-stop capability to avoid colliding with an obstacle. For speed regulation, the driver can operate at a comfortable speed until reaching a maximum speed limit, at which point a 'vibrotactile' vest on the seat belt informs them what degree of braking is necessary to return to a safe operating speed. If the vehicle detects an unavoidable collision with an obstacle, the vest cues the driver to stop immediately. For steering guidance, a potential field algorithm provides path generation. After calculating a path, the system instructs the driver where to steer to stay in the lane and avoid obstacles. The driver is told how many "clicks" to turn the steering wheel via a pair of headphones and LabVIEW text-to-speech software. A mechanism attached to the steering column clicks every five degrees to provide audible feedback. Additionally, according to team leader Dr Dennis Hong, "We developed a prototype for a tactile map, which is conceptually similar to a high-resolution grid of regenerative Braille. The map places an image of the surrounding environment literally in the hands of the driver. Similar to the tiny holes on an air hockey table, a physical map is generated by passing compressed air through small pixels to depict the surrounding obstacles detected by the laser range finder. This device, appropriately named 'AirPix', allows the driver to "see" the surroundings and navigate safely through them. The audio and vibrotactile NVDIs are still necessary for redundancy, but using the driver's high-bandwidth sense of tactation through this tactile map technology makes data pathways available for other driving uses, such as listening and interacting with a GPS through voice-recognition software for higher-level path planning." Other potential applications for the technology include interfaces for the military, who often want to control equipment in the dark without needing lights, and interfaces for aircraft cockpits that would allow pilots to safely land even when the cockpit is full of smoke.