A built-in camera on the belt senses items as close as 30cm (11.8inch) and sends vibrations through patches worn on the chest and ankles.
Developers at University Hospital Southampton (UHS) believe the technology could be the ‘next generation’ of visual aid.
There are almost 25.5 million people living with sight loss in the US, and 2 million in the UK.
A UHS spokesman said that the belt consists of a 3D depth-sensing camera and a portable computer stick connected via WiFi to vibration patches hidden on a vest and ankle straps.
It scans the area in front of the person using the 3D camera and warns the user about nearby objects through vibrations, the faster the buzzing, the nearer the object, with the position indicated by the left, centre or right patch.
The technology, known as the Low-vision Enhancement Optoelectronic (LEO) Belt, is currently going through trials at UHS.
A small study has already shown it can help people with retinitis pigmentosa (RP) successfully navigate a maze. RP causes a loss of peripheral sight like tunnel vision and can make it difficult to see in low light. It starts in childhood and gets progressively worse.
Professor Andrew Lotery, a consultant ophthalmologist at UHS who ran the study, said, “In this small pilot study we have shown the belt has great promise and, based on what we have learned, intend to develop it further to hopefully help patients retain their independence despite sight loss.”
Lotery said, “The belt has the advantage over alternative aids for people with sight loss, such as a white stick or guide dog, in that it can be worn under their clothes and be relatively discreet.”
In the study, six patients with advanced RP and 20 unaffected people wearing goggles that restricted their vision were assessed.
The results, published in the journal PLoS One in October, showed all participants were able to use the belt to guide them around four mazes made from obstacles arranged in different ways.
Wearing the LEO belt, the participants made 44 per cent less errors in the maze than when they didn’t have the belt on.
Those with RP said they found the belt ‘particularly useful’ when finding their way around the mazes in low lighting when their vision is worse, regardless of severity of vision loss, all participants were slower to complete the mazes using the device.
The authors concluded The LEO Belt’s positive user feedback suggests it has potential to become the next generation of visual aid for visually impaired individuals.
