Sensing Sensors, or the Sensor Walk

This week for our Physical Computing class, one of the assignments was to take a walk around our neighborhood, and observe the different kinds of sensors in place all around us.

Living in New York City, most people have buzzers outside their apartment buildings. It functions essentially like a doorbell, except that sometimes people on the sidewalk can speak into them to prove that they’re the pizza delivery guy and not some crazy ax murderer.

buzzer / intercom / how to get pizza delivered to the right place!

All over the city there are somewhat defunct payphones, which don’t see much use nowadays. I did see someone using one, and from her accent deduced she was Australian, so I guess if all you have is phone card they’re still pretty handy. Again, the sensors are primarily buttons to dial, then a microphone to talk into, as well as speaker to hear from.

surprisingly, there are still a lot of these in new york! they took them all out of san francisco.

Mostly I saw people walking down the street concentrating intently on their mobile devices, which contain a lot of different sensors if they’re “smart phones,” accelerometers, capacitance sensors, gps, etc.  Even if they’re not “smart” they still have a bunch of sensors.

Another common sensor I saw everywhere were ATMs. You put in your credit card, enter you PIN, tell it how much money you want, and bam, it spits out $20 bills (provided you have the funds). In New York, there are locked doors barring the non-cardholders from entering while you make your transactions. So even before you start pressing buttons, you have to insert your card into a card-reading lock, sort of similar to hotel card keys, that unlocks the door for you.

ATMs behind locked doors, to keep the card-less out

ATM card reader, insert your debit card to unlock and get money!

One of the next sensors I noticed, and one of the more interesting I found on the walk, was an electronics store’s window display, which had a live video feed of the people walking outside on the sidewalk. Unfortunately, I seemed to have documented the display, not the sensor, which I’m assuming was a small USB camera.

these guys were also excited about seeing themselves in the window

Last, but not least, was a sensor I interacted with at the gym. My elliptical machine would get very upset if I didn’t hold the handles so that sensors could calculate my heart rate as I exercised. Here it is telling me to put my hands on the sensor. The little pixelated heart is kind of endearing, so after a while I complied. I guess the machine had my best interests at heart. ha.

You can't see the actual sensored handles here, but you can see the heart!