Phil asks:

A geek friend of mine suffered a stroke last week and will be in a rehabilitation hospital for a few weeks. His room has WiFi in it.

I’d like to make him a device with a single rocker switch (or slider switch) where he can indicate whether he is up for having visitors.

The setting on the device will show up on a web site (that I make) where there will be a green light saying: “Jim is up for having visitors today.” or a red light with the words: “Jim would prefer not having visitors today.”

Could this be done pretty simply with an Arduino? How about the wifi communications part?

Sorry to hear of your friend’s stroke, but how nice of you to want to make something to aid in his recovery. Your idea immediately reminded me of a project done at ITP called Is The Floor Open. It is a simple knife switch attached to an Arduino with an Ethernet shield that forwards the switch state to a website and Twitter account. Co-creator Greg Borenstein (author of Making Things See) writes:

The structure of the project was as follows:

– Arduino w/Ethernet shield that looked for a change in the state of the switch: open->closed meant floor closed at the end of the night. closed->open meant floor opened in the morning. When it detected that change it made an HTTP POST to a web service

– That web service was written in Ruby using Sinatra and DataMapper and runs on Heroku. The web service receives the data from the Arduino, records the time of the event and which direction the switch was thrown. It sends a tweet to twitter under the credentials for the istheflooropen twitter account. It also displays the current status on one web page and the full log of all received events in the past on another.

Greg has documentation of different versions of the Arduino code at these two links. However, if you need to connect to WiFi, the Ethernet shield isn’t the right beast for your needs. You’ll need something like the Cupperhead WiFi shield, and then you’ll be able to connect to the hospital’s WiFi network.

I hope this helps, and that your friend makes a speedy recovery. Please let us know how your project works out. And for readers, please give any suggestions you have for Phil in the comments.

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