blog

sensor "day"

instead of doing a purposeful "sensor walk," i tracked the sensors i noticed from when i got up all the way through arriving at red's class last night.  here are some of the more interesting observations:

1. car alarm

this morning i was woken up by a very loud car alarm going off right outside my apartment.  after i got my head together enough to comprehend what was going on (and connect it with what i was studying!), i realized that the car alarm noise was triggered by a sensor that responded to any stimulus that might indicate that the car was in danger of being damaged or stolen.

2.  mouse touchpad

as i was checking my email and beginning to complete some assignments for class after i got up, i noticed that the trackpad on my laptop (and the keys too, if you really think about it) was also a sensor -- it reacts to the stimuli that i provide when i tap it, drag my fingers across it, press it, etc.

3. traffic light

in new york these don't count, because i'm pretty sure they run on a timer.  but back where i grew up in ohio, the traffic lights were actually triggered in part by a sensor that determined that a car was waiting at a red light.  otherwise, the green that permitted the intersecting cars to go through would have stayed on for as long as the sensor wasn't activated (which could be frustrating for drivers who didn't realize they had to pull up to a certain spot to trigger the light).

4.  atm

off to deposit a couple of checks.  citibank's atms have touchscreen interfaces, with the exception of a keypad used to enter the PIN on screen.  i did that, and then on screen i was able to choose from a variety of things i could do on the atm.  the system responded to where on the screen i touched.

citibank has also recently modified their atms to include a cool new feature: envelope-less deposits.  this means that their new atms actually have sensors in them that are able to tell how many checks someone is depositing in the machine at once, as well as a mechanism that allows it to read the amounts.  here's some video of it in action:

5. bodega door opening bell

as i walked into a bodega, the bell went off every time the door was opened or closed.  there had to have been a sensor connected to the door somehow that would indicate when the door had moved past a certain point.

7.  metrocard swiper / subway doors

the sensors in here can tell when someone has swiped their card, as well as activate the grate to open when a card has been swiped correctly.  in the same way, the subway doors can tell if there is someone obstructing their path to closing; they will automatically open when there is someone or something in the way (that is, if they're working correctly).

8. automatic toilet/sink/hand dryer

when i arrived at cantor for red's class, i went to the bathroom before going inside.  the toilet flush, sink, and hand dryer were all programmed to automatically activate when they felt the presence (or lack thereof, in the case of the toilet) of a human body.

there are many more sensors that surround us every day; these are the ones that made an appearance yesterday morning and afternoon.  i'm sure that with more extensive observation (ie, more than a few hours), many more could probably have been detected.  for example, i saw a car backing into a parking spot and was immediately reminded of cars with backup monitors installed, which are only active when the car is in reverse.  it's evident that sensors have an enormous impact on how we live our lives.

pcompRoopa Vasudevan