The problem of the last ten yards
We're all extremely familiar with GPS and how helpful it is at getting us from A to B relatively unscathed. We might make a wrong turn or two, but in the end we get there with our wits more or less in tact. The limitation of GPS, however, is that it is at very best accurate to within 10m - 5m give or take either way. This is usually ok for driving (although we've all experienced much higher levels of inaccuracy - which happens when fewer than the maximum of seven satellites are visible to the device.
If you're blind or have a significant vision impairment, then nearly being at your destination isn't good enough. GPS can often have you an entire street out, let alone give you pinpoint directions for when to reach out your hand to find the door to the store instead of feeling your way along a featureless wall of windows. Being out by a few feet (or even inches) when you're blind is a bit like dropping your phone and it nearly missing the cold, hard Mexican ceramic tile (retro film reference). This is known as the 'Last ten yards' problem and, for many blind people with significant mobility challenges, a miss is as good as a mile.
Getting smarter with indoor navigation
Using GPS indoors is even less accurate. The signals from satellites are all but obscured and so indoor navigation solutions rely on other technologies such as Bluetooth beacons.
Beacons send out a Bluetooth signal that a smartphone, for example, can use to triangulate your position with extreme accuracy. The drawback with beacons, though, is that they need to be set up, programmed and maintained in every single venue you visit. You also need to have the right app to access them and, even though excellent open source initiatives such as previous Tech4Good winners ‘Wayfindr' are trying to standardise on the way that beacons provide this information, there's no one single app that all venues use to take this information and help guide the user.
Enter Clew - an entirely new approach to indoor navigation.
Clew - providing a clue to the future
A new app designed by a research group at Olin College of Engineering uses a very different approach. The above heading might sound a bit pompous, but how this app tracks an individual's path from A to B is about as futuristic as it gets.
Clew uses Apple's augmented reality tools (called 'ARKit') and your smartphone camera to analyse the objects that you pass and use them to accurately judge distances walked and angles turned - right down to those last few crucial centimetres. Let's see it in action.
This surely, then, is the future of navigation. It works best indoors, where key objects such as furniture, doorways and windows etc are static and the lighting not overwhelming. It does work outdoors too, but comes with a warning that bright sunlight and moving objects (such as vehicles) could confuse its algorithms.
I've used it several times myself - firstly walking a wandering indoor route with numerous turns and a flight of stairs and each time it has effortlessly instructed me back to my starting point without a wrong turn or untimely instruction. It's truly amazing.
A truly empowering use of augmented reality
ARKit wasn't designed to help disabled people get around in a complex world of course - it's much more about making monsters emerge from virtual holes in otherwise blank walls or turning your dining table into a 3D map on which to play mini Minecraft. However, the exact same need to recognise vertical and horizontal surfaces and where they start and finish (in order to make the virtual bits feel firmly fixed in the real world) means that apps like Clew can guide someone through that real world with pinpoint accuracy - and without them coming into painful contact with those surfaces along the way.
The smarts embedded within ARKit make building such apps cheap and straightforward - or at least vastly more straightforward than ever before. Whilst Clew is little more than a prototype at this stage (it won't as yet enable you to save routes for future use or share them with friends) it is a fully-functional prototype that is incredibly effective in what it does. It takes the hit and miss out of indoor navigation and, like the phone that just misses the rug and lands on the tiles, a hit is definitely something that blind people could do with a little less of… so a big thanks to the Clew team and here's to future features making it a must-have app for blind users everywhere.