Motion Sensor ->ATTiny-> RFTransmitter -> XBee->Arduino WiFi

Projects General Guidance
1

Good Morning!

After doing a very interesting research paper on "The Internet of Things" for a Masters course on Distributed Computing, I've become interested in some of the DIY technology available. I've got an idea for a project, but I wanted to see if it would be feasible before I delve any deeper. I only really have a vague understanding.

I want to create a network of motion sensors that, instead of simply setting off an LED when triggered, instead create a digital artifact/record of the event. (Someone walks in front of it, sensor ID and timestamp info are generated). I also want this sensor to have the smallest footprint possible so I'm thinking Motion detector, ATTiny and small RF transmitter (and whatever other electronic components would be necessary).

The RF transmitter would transmit to a gateway device that receives the RF (6LowPan?) signal up the 802.15.4 stack , converts it to a serial signal, then back out over standard 802.11 WiFi to a Router, then out to a server to be stored as a database entry. I'm thinking this would require an Xbee Series 1 (to receive the signal) and an Arduino WiFi (to transmit the signal) with some sort of bus interface in between.

Are there holes in my logic? Fundamental misunderstandings of the technology?

Thank you!

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Are there holes in my logic? Fundamental misunderstandings of the technology?

Could be. If the Arduino with WiFi shield is going to be using an XBee to receive data, the other devices must also be using XBees to transmit data.

If they are, then they have microprocessors built in, and the ATTiny at the transmitter nodes contributes nothing.

Other than that, the rest of the scenario is plausible. Personally, though, I'd skip the Arduinos altogether. An XBee with motion sensor at each node and a XBee and USB Explorer connected to a PC. Run an application on the PC that gets data from the XBee, and stores it locally or in a database (local or remote) if that's more convenient.