PCOMP – Week 3: Observation & Analog Input

On Saturday, Sep 22nd, I volunteered at the World Maker Faire hosted at the NYC Hall of Science. It was a precious and wonderful experience – I was able to see tons of interactive projects, to engage with the bigger maker community, and to learn from some of the most innovative people in NYC.

Among all projects that I got a chance to visit, one impressed me the most – an Umbrella-sized Planetarium. It looks like this:

It did not have fancy LEDs blinking all over, from top to bottom; it did not have techie-feeling AR/VR scenes through which you can peak in to the future; it did not even produce a single sound. But in my opinion, it is a brilliant project, because:

  1. It cleverly adopts and integrates the conceptual model of an umbrella, where you would always hold it UP to keep the rains from falling onto you, and that of a planetarium, where you would always look UP for the stars. These shared UPWARD motions provide a clear and intuitive mapping for me to understand and use this mini-size planetarium.
  2. The handle of the umbrella provides an affordance to grip and turn it around. The blue straps are tying up the wires and they somewhat work as the signifier for gripping and holding the umbrella up. The monitor attached under the face of the umbrella is turned on and emitting bright light, which serves a signifier for the eye to look at. All possible actions are clear.
  3. The image on the monitor refreshes right after I pick the umbrella up. So the feedback is immediate. The star images shown on the monitor aligns with what we see in an actual planetarium. So the feedback is informative.
  4. And last but not least, the pattern on the umbrella looks good 😀

My observation on how people use it somewhat resonates with my own experience:

  1. When people saw this umbrella first (which is laying horizontally on the table), most of them would look straight into the monitor first (for about few seconds). Then they would put their hands around the handle, and held up the umbrella. The others would just held it up first and then looked to the screen. No one seemed to be confused about how to use it during my observation period.
  2. The fun part began when people started to turn the umbrella around. As long as the monitor image was synchronized smoothly and correspondingly with the portion of sky presented under the planetarium, people would happily pointing left and right, up and down to check the different stars. But once the image got delayed and did not sync with the movement of hands, people would seemed a little confused and tried to adjust the pointing direction of the umbrella, and to figure out where to point exactly. This little mess would generally take 2-5 seconds to resolve.
  3. The entire exploration of the umbrella planetarium went from 10 seconds to about a minute. Overall, I believe most people found it intuitive to use and had some fun exploring this tiny piece of starry sky.


Analog Input & Digital Output

I continued my series of reflection on my mental states this week (it’s called Fahrenheit Fright) by trying to resolve my frustration with the Fahrenheit system with a simple analog input and digital output system.

Here are the components:

With a temperature sensor and three LEDs in different color, I measured the Fahrenheit degrees in the environment, transformed them into the Celsius system, and categorized them into three discreet levels – levels that I use as guidelines for dressing up daily:

  • Blue LED lighting up with any temperature under 26 C =  It’s a bit cold;
  • Green LED lighting up between 26 – 32 C = It’s comfortable with one T-shirt;
  • Red LED lighting up above 32 C = It’s hot! No need to bring any long-sleeves.

Here are the outputs:

And there is how it works in actual environment:


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