The domain of haptics has immense potential as a technology to assist visually-impaired individuals with their navigation of the physical world. In this project, we sought to develop a 2-DOF haptic joystick to provide force-feedback to a user as she attempts to navigate a maze – with no visual feedback whatsoever. The proof of concept we show here takes a given maze, and renders it as a 2D navigable virtual environment.
We see many applications in the field of haptics to improving the quality of life for individuals with disabilities. In particular, the reliance of haptics of the sense of touch lends itself to aiding the visually-impaired. Consider the case of a wheelchair-bound individual with a visual impairment. Even with modern wheelchair technology, the burden of safe and effective navigation through the environment is entirely on the operator of the wheelchair. If the user is unable to see obstacles and visually sense a clear path, the assistive technology that the wheelchair provides is effectively useless. The 2-DOF haptic joystick is an attempt at remedying that problem. By coupling traditional joystick navigation with force-feedback, haptic joystick technology could allow visually-impaired, wheelchair-bound users to safely navigate their environments.
Our project is half of the solution: not having the ability to generate real-time map information, our device is reliant on pre-determined “mazes” to simulate the notion of a navigable space. The next step would be using real-time environmental mapping (such as with the Kinect’s depth sensor) to generate “mazes” on the fly, allowing the virtual environment to truly mimic the user’s surroundings and provide useful haptic feedback.
There exist many other haptic devices that allow for 2-DOF movement. For example, Jared and Sam created a planar 2-DOF device to emulate gravitational forces. All-purpose haptic feedback joysticks are also common, which often provide vibrational feedback during video games. Other special-purpose joysticks have also been created, for MRI applications, wheelchair navigation, and motor driving. A number of different implementation schemes are employed, both for sensors and actuators. Popular alternatives to our optical encoder sensing set-up include potentiometers and magneto-resistive (MR) sensors, as in Prof. Okamura’s 1D Hapkit design. On the actuation front, gears and chain-drives are common alternatives to the rubber friction drive model we show here.
For more detail: Liam Rishi Sydney Blind Maze Navigation using 2-DOF Haptic Joystick