In Part 1, I introduced the architecture and shown some sample charts of my Smart campus project. The non-intrusive use of WIFI data for campus services and student experience is really cool.
As we are approaching the start of university term, I have reduced time to work on this project. So my focus was to prototype a “student-facing” application that visualise live building information. The idea is students can tell which computing labs are free, where to find quiet study areas or check if student helpdesk is too busy to visit. Security team can also use that to see if there is any abnormal activities at certain time of the day.
The chart below shows a screenshot of a live floor heatmap with breakdowns of lecture rooms (labelled white), study areas (also labelled white), staff areas (labelled black), and service areas (labelled grey).
Technically the application is split into three parts: user facing front-end (floor chart), data feed (JSON feed) and backend (data processing). The data feed layer provides the necessary segregation so that user requests don’t trigger backend operations directly.
The front-end chart is still based on Highcharts framework though I needed to manually draw the custom map using Inkscape based on actual floor map, export the map as SVG, convert it to map JSON using Highcharts’ online tool. At the same time, the mapping between areas (e.g., lecture rooms) and their corresponding APs must also be recorded in the database. This is a very time consuming process that requires a bit of graphic editing skills and a lot of patience.
The backend functions adopt a “10 minute moving average window” and periodically calculate the AP/area device population to generate data for each area defined in the custom floor map. I also filtered out devices that are simply passing by APs to reduce noise in data (e.g., a person walking along the corridor will not leave a trace). The data is then merged with the floormap JSON to generate the data feed every few minutes in static JSON file format.
A finishing touch is the chart annotation for most floor areas. I use different labelled colours so areas of different functionalities can be clearly identified.