The document discusses robotic and bioengineering technologies that help people with disabilities. It describes two devices: the NavBelt, which uses ultrasonic sensors and audio signals to guide the blind user around obstacles, but is difficult to comprehend quickly enough for fast walking. The newer GuideCane overcomes this by being a wheeled device attached to a cane - when it detects an obstacle, the user can feel it steer around the obstacle and follow its new path easily. Both devices aim to help the visually impaired navigate via robotics and bioengineering technologies.