Death by Tactile Paving | Hacker News Reader

Death by Tactile Paving

99percentinvisible.org

95 pointsmisnamed38 comments

Not to take away from the specific challenges of blind people, but this is a broad problem whenever there is a mismatch between the map and the territory. The mismatch can come from sloppy work or just from the way the world changes over time and the map doesn't keep up.

I've seen plenty of cases in IT systems where bad documentation is much worse than no documentation. For example, there are the ubiquitous handover docs (demanded by project managers everywhere) filled with pages of cable connectivity, MAC addresses, WWNs, LUNs, etc in Word tables or manually-edited spreadsheets. They should all read "For historical purposes only" because you will inevitably trip over reality if you rely on them for live systems.

Similarly, there are those that insist on beautiful, meaningful patterns for naming all components. This works great until the pattern can no longer continue, or someone is sloppy, and then the pattern is just a tactile strip leading to a hole in the ground.

The solution I've settled on is live, automatic documentation in the form of scripts that generate a bunch of CSVs (or populate a table somewhere to drive a dashboard). CSVs are nice because they are easy to generate and version. I guess JSON would be more trendy these days.

I avoid manually-edited living documents and put clear warnings on any historical documents. And as much as possible I avoid patterns in naming and numbering, although that's a hard sell for a few clients.

Taking it back to the tactile indicators, I'm reminded of the (apocryphal?) story of what one university did when they landscaped their campus. In the first year they didn't put any paving down. In the second year they paved the worn-down paths in the grass. If only there were some universal way to "grow" tactile strips based on the actual movements of pedestrians.

Another thing to look out for in cities (and get people to correct if you can - report to the city, building owners, and so on): Things that stick out at head level that have no indication of their existence at ground level. Cane users would not feel an interruption and so would have no warning before getting cold-cocked right in the face. I notice this a lot where there are dramatic stairways that you can walk underneath. Best to have some sort of railing there.

> Things that stick out at head level...

I'm a tall man (200cm/6'6") and walking down the street in the rain in Hanoi was a test of nerves, as mains power cables would shoot giant sparks at just about eye level...

It can be worse, on my way to work there was some sort of a nail sticking out of a wall at head level, that I almost ran into a few times (thin, and hard to see against wall), and I am a seeing person.

This may be naive, but that sounds like a good use case for a head-mounted collision-avoidance system (like the ones in self-driving cars). I bet you could fit such a thing in a fairly light-weight headband nowadays.

On the contrary: it's not naïve, it's far too advanced. This isn't a problem that needs to be solved with technology and by forcing people to wear a beeping device on their heads. You can just install a railing and make the environment safe for everyone.

I suppose your solution would work as a stopgap, but it seems like poor design to make people adapt to human-made environments rather than building the environments in a way that works for everyone.

"This isn't a problem that needs to be solved with technology and by forcing people to wear a beeping device on their heads. You can just install a railing and make the environment safe for everyone"

One problem with the "just install a railing" approach is that the environment changes. New stuff gets built. Temporary obstacles appear where there were none before. Not all obstacles are human-made (think about walking through the woods -- there will be no railings there, to be sure).

Another problem with it is that the person who benefits (the blind person) is not the same person as the one who must be relied on to alleviate the problem and foot the bill.

Also, why is wearing the headgear "forcing" while using a cane is not? I don't think anyone's being "forced" to do anything in either situation.

I think another reason why "just install a railing" doesn't address the problem if you can't see, you're counting on everyone else realizing the problem and fixing it with a railing, whereas a head-mounted collision-avoidance system works whether or not anyone else realizes there's a problem.

Ideally you'd have "defense in depth" such that your head-mounted collision avoidance system is just a fallback, but honestly it's one of those things where it would be best to take it into your own hands if possible.

while I agree that the best solution is a better environment, you could fit the sensor to the obstacle, and have it beep when something comes close :P

That comes with all the additional requirements of a technological solution - power, maintenance, reliability etc. A simple barrier will continue to work even after the local kids have tagged it.

I would not want to live/work/sit near such a thing.

Great, now we're going to see random beeping devices places around SF where people don't want the homeless to congregate.

Only if they look like cool cyberpunk googles.

I live somewhere not mentioned in the article but we have tactile paving too. I have never once seen a blind person using it (no, I am not blind myself). On the other hand I did see construction workers installing it, and it seems to take quite a bit of extra effort.

So I wonder: are these things useful to people other than the tile makers, for whom government mandated special tiles are undoubtedly a fantastic revenue stream?

Haven't read the article, but as a blind person myself, nope. Much of the infrastructure designed to "help" us is so inconsistent, non-intuitive or broken that I don't bother using it, far preferring my own skills and knowledge of my surroundings.

For instance, I have an audible signal near my house. Sometimes it works. Sometimes it doesn't. Sometimes one side of the street works, and which side that is varies from day to day. In Austin, we have a variety of signal designs with no standard placement and, in some cases, a non-intuitive pattern of beeps which you can only learn by listening to the traffic patterns and correlating them with the sounds. So, in short, if I walk up and press a button, I have no indication whether that button will give me an audible signal, and historically giving me a signal is no indicator of getting one in the future. I feel truly sorry for anyone who actually needs the things. For my part, traffic never lies unless you get a bad driver, in which case an audible signal wouldn't save you anyway.

Thanks for reading my mini-rant on the fucked-up state of shit to "help" blind folks. :P

Thanks for that, it's very interesting. The blind people in my city seem to just walk around using their senses without special tiles. Once in a while they speak up and ask someone to help them, but not often.

As a cyclist I sometimes feel the same as you: special accommodations are often inconsistent or inadequate to the point that they are not useful except to casual users. And I don't think there are casual blind people.

So, in short, if I walk up and press a button, I have no indication whether that button will give me an audible signal...

Probably for that reason, the audible signals around here are audible all the time - there's a slow tempo signal for "stop" and a significantly more urgent, higher tempo signal for "go".

Are you an engineer? I ask because you're on Hacker News.

I've long been curious what the day to day workflow is for a blind engineer. Particularly if there are any folks doing software development.

I'd be tempted to believe the kind of pseudo-visual thinking required for software design is exercised more in someone who has to construct their surroundings without visual input.

I'd also be happy to be told I'm wrong. I seek to understand.

Here's a fairly recent post (or two) about being blind and a developer.

https://www.parhamdoustdar.com/2016/04/03/tools-of-blind-pro...

I know at least two blind people who worked on actual coding (in C++). Obviously, both of them had rather important advice to give the accessibility team. :-)

The topic has come up before: https://hn.algolia.com/?utm_source=opensearch&utm_medium=sea...

Move to Australia, where we have a standard audible pedestrian signal/button design used nationally...

http://theconversation.com/sublime-design-the-pb-5-pedestria...

Here's a UK one, I love showing friends and random old people it's there, it's usually news to most people! http://www.bbc.co.uk/news/blogs-ouch-22706881

Interesting - here in Oz the vibrating device is on the face above the push button. I'm not sure whether it's easier to locate if you're blind/vision-impaired and thus actually need it, but it's certainly a bit more obvious for sighted folk.

I have perfect senses, but if I'm using my phone to write a message or something I'll follow the tactile path to avoid walking into something.

Per a blind friend of mine, they are useful. Both for himself, and as cues for his dog.

Keep in mind also that far more people are vision-impaired than totally blind. Being high contrast and tactile helps those people navigate as well.

I noticed this in Beijing in 2007 (I'm a wheelchair user, so I'm looking at the sidewalk a lot). Here's a photo of one of those bumpy yellow paths leading straight to a steep flight of stairs under Tiananmnen Square! I've always thought back to it as a perfect example of things people try to implement in order to help disabled people but that have the opposite effect of help. Anyway, a good example of a well-meant but bad user interface!

https://www.flickr.com/photos/lizhenry/1571135450/

Caption from a photo: "Tactile paving used to create decorative patterns or zigzag routes."

Zigzag routes. That sounds terrible. I'm having a hard time articulating my reaction here, but can you imagine a moderate crowd on the sidewalk, most of them seeing, and a blind person attempting to zig and zag through the crowd?

Believe me, the decorative pattern is even worse. It consists of an alternating horseshoe-like pattern, only square, so anyone following it would not only zig-zag, but alternate back and forth.

Of course, blind people are not robots and would soon realize the nonsense, but surely it can't help anyone.

The decorative pattern could be interpreted as a "fuck you blind people" sign.

Of course, incompetence is more likely, maybe the worker installing them had no idea what to do with the yellow tiles.

It could be worse - they could create closed loops on which blind people would get stuck until they figured it out.

It's a perfect example of what happens when a designer has to use a set list of components but isn't aware of the reasons behind the components chosen.

I've been wondering if there was a reason for those tiles to be yellow. Sure, it allows non-blind people to spot mistakes more easily, but it also seems that those wouldn't have been used as a decoration in the first place if they had been available in different colors (that said, never underestimate human dumbness).

I've also been wondering at the material those are made of. I am used to white, plastic dots, and I find them slippery when it rains, which is a bit dangerous, since they indicate danger area (they can get especially slippery/dangerous with roller blades, but that's not a great idea when it rains, altogether).

Most blind people can still see something.

It depends on your definition of blindness.

About 10-20% of the US population self-report vision problems. About 20-30% of them reach the definition of legal blindness, which is vision that cannot be corrected to above 20/200 in at least one eye. About 20% of that population are totally blind, which is to say that they cannot even perceive someone shining a light in their eye. In the US, that amounts to about 200,000 people.

By the way, the point of tactile paving is usually to indicate a change (like a slope or a step) about to happen, warning of an edge, not a path that you are supposed to follow.

Dots indicate change or hazard. Parallel lines, on the other hand, are meant to be followed.

I've wondered what the yellow raised line down the middle of Palo Alto Transit Center was supposed to mean!

Unfortunately, I think it stops around the time it reaches the steps to the train station.

On the other hand, San Jose Diridon doesn't have tactile paving, but it does have some sort of "talking sign for the blind" things telling you which paths to take, and where to stand!

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