For my independent project, I continued to explore the bus shelter idea, working on the technology that I could use to realize it. For this iteration of the bus shelter, I focused on communication: either between two shelters (relevant to the earlier game/communication ideas, or between a bus and a shelter. This variation would allow a waiting passenger to know when the bus is approaching, perhaps by flickering colored lights in the ceiling/roof of the shelter. The lights get brighter as the bus gets nearer (as the diagram below shows, which I include in lieu of a video) and could be different colors for different routes.
Emily and I submitted a proposal to an upcoming local art festival with this idea, and the limited budget encouraged us to look at other solutions besides the Arduino. I am interested in using RF for this project, as wireless access may be spotty and RF options are low-cost. I came across the JeeNode as one potential option: it uses the same chip and programming environment as Arduino, but has a smaller footprint, requires only one AA battery, and has an on-board RF transmitter (so it can send and receive messages).
For this project, I focused on getting two JeeNodes to talk to one another. It is still fairly basic, but (as in the images below) one JeeNode sends a message every second and the second blinks when it gets that message.
The messages can be up to 66 packets in length. The interesting thing is that when the JeeNodes are far apart, not all of the packets are received. I realized that this could be utilized as a de facto proximity sensor: the LED's brightness could be determined by how many packets are received, so that it would be brighter if the transmission was strong (the two JeeNodes are close together) and dimmer if the transmission was weak (they are farther apart). I haven't been able to get this part of the programming working yet, and there will most certainly be problems with my logic about the proximity sensor thing, but I'm excited to keep playing with this idea over the summer with the goal of installing it, if only temporarily, in a bus shelter some evening.
My code is in the files below, which require additional libraries for the JeeNode.
bus_shelter_sender.pde
bus_shelter_receiver.pde
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