Monthly Archives: November 2014

Plexiglass (acrylic) case for sensor node

I got a laser cut plexiglass case made for WiSense node. The plexiglass sheet is around 2.75 mm thick. The node is sandwiched between two sheets (top and bottom). The sides are left open. The top sheet has cut outs for the antenna and the two 2×6 connectors. The bottom sheet has cut outs to expose the two 2×6 conectors. The idea is to provide some level of protection (including ESD) to the node. I am not entirely satisfied with the look.  I prefer curves to straight cuts. Hopefully I will get a better look in the next batch. The case is not cheap. We will make it optional.

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WiSense coordinator connected to Raspberry Pi

The coordinator node can be connected to the USB port of the raspberry Pi. The USB port will provide power to the coordinator as well as serial connectivity between the Pi and the coordinator node. When the USB cable (connected to the coordinator node) is plugged into the Pi, a /dev/ttyUSBx device will be created. You can run the “dmesg” command to get the name of the serial device. It will usually be /dev/ttyUSB0. The USB chip on the coordinator is an FTDI device which is supported by the Pi.

You just need to copy the gateway utility and the sample xively app (which sends sensor data from sensor nodes to xively) to the Pi and you are ready to send data out.

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