Robotic navigation aids the visually impaired

Compiled by Photonics Spectra staff

A robot vision-based mobility aid that was shown a year ago is now being further developed to help the visually impaired navigate city streets, neighborhoods, offices and other complex locations.

This robotic navigation system has a binocular camera that is linked by sophisticated direction-finding software to a vest that directs the wearer around obstacles. Images courtesy of USC Viterbi School of Engineering.

Most visually impaired people still rely on a very rudimentary technology – a simple cane – to navigate the world. Meanwhile, engineering researchers at the University of Southern California have developed software that “sees” the world. The software is linked to a system that provides tactile messages that alert users about objects in their paths, such as low-hanging branches.

The system uses a camera that is worn on the head and connected to a PC that uses simultaneous localization and mapping software to build maps of the environment and to identify a safe path around obstacles. The route information is then conveyed to the user through a guide vest that has four micromotors located on the shoulder and waist. They vibrate like a cell phone.

Simultaneous localization and mapping software analyzes data from stereo camera views (above) to create 3-D renderings of the scene (below) and to map a path through it.

If a low-hanging branch, for example, is to the left of a visually impaired person, a micromotor will vibrate on the left shoulder. Scientists say that this technology, unlike a cane, will enable the user to avoid falls and other serious injuries when approaching larger objects.

The researchers tested the system on blind subjects at the Braille Institute and received positive feedback. They are now working on ways to improve the prototype. Because the head-mounted camera is bulky, they are working on a microcamera system that could be attached to glasses. The goal is to have the system in place by the end of the year.

Less bulky than the current head-mounted camera, the next-generation system the team is working on, pictured here, will use a microcamera that could be attached to glasses.

Funding for the research – which will be used to help veterans who have been blinded during their military service – was provided by the National Science Foundation, the US Army and the W.M. Keck Foundation.