[pcomp week 3] Design meets disability reading & observation

from the Alternative Limb Project
from the Alternative Limb Project

This week’s reading was Graham Pullin’s Design Meets Disability, discussing both objects explicitly used to counteract a disability, like prosthetics, as well as objects used by people of all abilities that have varying levels of inclusiveness. Glasses are cited as an example of successful design for disability, to the point that people don’t consider poor eyesight a disability because glasses have transitioned from being medical devices to fashion accessories. This reminds me of Norman’s phrase, “Attractive things work better.”

I appreciate this perspective in the context of physical computing. If we’re designing for the human body, it’s important to take into consideration the ways in which people’s bodies and abilities are different, and to not take any particular ability for granted. I think it’s neat to see examples of things designed specifically for, say, wheelchair users, but also to see products that keep different preferences of usage in mind (a clicking sound and sensation, for example.)

(A small note on the examples: it was fun to see Nick’s Bricolo because we used to work together at my old job before ITP!)


For my observation assignment, I decided to watch people use the entrance to the subway. More specifically, I watched them use the Metrocard slider that collects their fare.

NEW YORK, UNITED STATES - JANUARY 13:  A person swipes a metrocard in New York subway station on January 13, 2014 in New York, United States. The Metropolitan Transportation Authority (MTA) declares that MetroCard the subway rapid transit system is going to change until 2019. (Photo by Bilgin S. Sasmaz/Anadolu Agency/Getty Images)

According to the MTA, people swipe in about 1.7 billion times a year. That’s a lot! I’ve probably done it a thousand times myself.

That said, it’s certainly not perfect. My assumption is that people who are accustomed to the system — understanding which way to swipe and the specific speed at which you swipe — can move through pretty quickly within 3 seconds or so with no problem. But tourists, anyone that has insufficient fare on their Metrocard or any other Metrocard problem, or people that move too slowly I predict will have trouble with the machine.

I watched people use the machine at Union Square because there’s a lot of activity there, and locals and tourists alike.

I noticed that the people using the machines generally fell into three groups:

  1. Confident and experienced users who got through with no problem
  2. Confused users who had problems, likely tourists
  3. Confident users who had a problem with their card

The first group was the majority of users who moved through the system quickly. The second group usually approached the machines slowly and often in groups, and would often swipe too slowly or too quickly, receiving the “Swipe card again at this turnstile” message. They would try again and again until it worked. This usually would take something more like 10 or 15 seconds.

The third group actually ran into the most trouble. People who were experienced and confident moved forward with the speed of someone who would get through in a couple seconds, but were halted by the machine abruptly if the card didn’t work. Sometimes they would almost run into the turnstile because the momentum was carrying them forward. Other times there were almost collisions with people behind them, especially if they had to turn back to refill their card.

In the case of insufficient fare, people had to go back to the machines to refill them, which could take up to a few minutes.

Developing the correct motion to swipe in a way that the machine understands is a skill that improves with practice. This is probably one reason why most other (and more modern) subway systems around the world use a tapping system, which seems to be easier for anyone using the machine, even if they’ve never done it before.

The way to solve the insufficient fare problem seems to be harder. It’s not an issue of not informing riders of how much fare is left (since it’s on the display when you swipe in), but people forget that they need to refill even if during the last ride they knew they ran out. It seems to be an issue of when riders are notified that they need to refill, which should ideally be when they walk into the station and not when they’re already at the turnstile.

A shorter term solution might be to design the space around the turnstiles in such a way that people can quickly exit the turnstile area if they need to, so it’s not a crowded bottleneck.