A Tracing Pen for Blind and Visually Impaired Persons.

Berkovitz & von Wiegand

This Small Business Innovation Research Phase I project aims at development of a pen-like device to enable a blind person to find and trace the paths of conventionally printed or drawn lines on ordinary paper or in a book. Essentially, a simple machine vision device and accompanying logic circuitry are combined in a unit that constrains hand movements of the user when the pen is on a line. The device is to be self-contained and is expected to be about the size of a large fountain pen or marking pen, and will require no connection to a computer or other device. When moved across the paper, the pen would detect the presence of a line and control its resistance to motion so that the path of least resistance follows the line. The line could optionally be measured and the measurement announced acoustically. We plan to study alternative implementation methods, build prototypes embodying various features, and assess the functionality of the device and its features by laboratory tests. If the results of this research are successful, we will seek Phase II support for development of a device which can be manufactured. The design process in Phase II will be substantially guided by field testing during and after construction of working proto-types.

The product could be used for mathematics instruction and reading of simple maps and diagrams. Because we expect it to be moderate in cost, the stylus could also be used as a general-purpose free-hand tracing instrument. In the study of geometry, for example, its design could be enhanced to eliminate the need for separate straightedge, compass or protractor, extending its area of application.

Figure 1. Representative arrangement of parts for Rollipen prototype. 1. Free-rolling wheel; 2. Steering motor; 3. Optical sensor (circumferentially-arranged emitter-detector pairs); 4. Pen-shaped enclosure; 5. Electronics package (Power, Control, I/O); 6. Accelerometer (Tilt/gravity sensor); 7. Strain gauges (sensing force vector between case and wheel). Items 6. and 7. are only needed in the more advanced versions of the Rollipen.