CitySounds Talk at Smart Data and Smart Cities Conference

We presented an overview of the CitySounds project at the 3rd International Conference on Smart Data and Smart Cities in Delft on 4th October 2018. As you can see from the photo above, Delft was basking in warm autumn sunshine, so it was a great time for a visit.

Here’s the reference for the paper:

Klein, E., Chapple, S., Fainberg, J., Magill, C., Parker, M., Raab, C., & Silvertown, J. (2018). “Capturing the Sounds of an Urban Greenspace”. In International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol. XLII-4-W11, pp. 19–26. Copernicus GmbH. https://doi.org/10.5194/isprs-archives-XLII-4-W11-19-2018

Collaborative box building

Come and help us build some wooden tree boxes, which will be installed around the Meadows with microphones inside them for the CitySounds project. This will be a great chance to learn some basic woodwork skills, whilst also contributing to an exciting community project. No previous woodwork experience required!

Please register using this Eventbrite link.

Data is Flowing

We now have two Audio Capture Devices (ACDs) delivering encrypted audio data successfully to our CitySounds server. Interestingly, every now and again one of the ACDs loses some WiFi signal and goes dark for a minute or so — perhaps a delivery truck or other vehicle in the adjacent street is blocking the signal.

A separate server script picks up the audio data files as soon as they arrive and moves them to a separate, inaccessible file partition and re-encrypts them with a wholly separate encryption key.

First Prototype Device

Device in situ at test site  (plastic box at top)  monitoring bird feeders in normal and icy conditions.

We have prototyped a bio-acoustics listening device based on the Raspberry Pi Zero W and Dodotronic Ultramic. We are about to start 24hr continuous run testing in cold weather in two test sites. So far, the power consumption is pretty much as predicted considering cold weather.

A battery that delivers 30,000mAh should give 7 days continuous operation before needing to be recharged, and with a number of power saving options employed on the Pi, the initial tests have certainly borne this out. The cold weather (we have had several days of sub-zero temperatures and snow/ice) has much reduced the battery capacity, which is not surprising given the characteristics of Lithium-Polymer batteries.

Separately, we have now configured a Libelium Waspmote-based temperature, pressure, humidity sensing device to work within our existing LoRaWAN IoT infrastructure.