Measure/Kasiisi

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For The Kasiisi Project, I have modified the Measure activity for a class on environmental sensors for the XO-1. The program is posted and documented here - read this page if you would like to use this activity for your own project.

Measure Activity

Read more about Measure to learn more about what the activity is useful for, and what sensors have been applied to it.

Differences

Simplicity

  • The activity starts with the Sensor toolbar and view, not the Sound toolbar and view
  • Sensor input is converted to a readable number (Celsius or a light "percent") and displayed in real time.
  • The graph shows the last 3 to 5 seconds and gradually scrolls across the screen, so you can observe changes. For example, you can cover and uncover a light sensor and see the difference appear on the graph in real time.
  • The graph is flipped so that increases in temperature and light appear as a rise in the graph's value

Support for RFID

RFID is essentially a radio barcode. A tag the size of a quarter is placed on or inside an object. When that object passes within a few inches of an RFID reader, its code is automatically scanned.

The Kasiisi Sensors project will be using RFID as a bridge between students' real-world artwork and digital information. For example, a student could draw a tiger, stick a tag on the back of their paper, and write a short article on tigers, including photos and links. When the tag is scanned, the Measure activity will load the student's page. Students could also tag a sculpture/model, book, poster, or map. Tags can be re-used, and more tags can be bought at $1 each to expand the library. When RFID tags become cheaper ("like dust", some say) you can imagine connecting every book in a library and every place on a map to its digital counterpart through RFID tags. However you use RFID, it lets students create objects at the cutting edge of real and virtual.

Adding Sensors

Give yourself some time to test the sensor and consider how it will be read over the analog microphone jack. The microphone jack has a small power output, too small to light up most LEDs. If you want a 5-Volt power source or have a difficult-to-interpret sensor, it may help to use an Arduino.

Edit drawwaveform.py to add more sensors, write numbers to the pango layout form (where Temperature and Light values are displayed) and cue the browser window.