chicago transit authority / 24 hour data visualization

CTA Dynamics is an interactive visualization of transportation dynamics during a day in Chicago. This project was presented as part of the University of Illinois at Chicago (UIC) Information Aesthetics class. CTA Dynamics is an interactive visualization of transportation dynamics during a day in Chicago. The interface allows to visualize how the density of buses running in the city changes over a 24hr time interval. The visualization uses GPS data collected from each of the buses. A short script was written to collect this data. The script would query the CTA website every 5 minutes and get the information for all the buses running at that time. The information was retrieved in XML format. Additional data like the time and date for the query was added by the script. A Processing sketch was then developed to visualize the data. The sketch starts by parsing all the data, creating a Bus object for each bus found on the file. Each Bus object has its own id and an ArrayList of objects containing their position at every time data point. The program then iterates through all the time data points and ask each Bus object to draw at its corresponding position at the corresponding time. Each bus is represented by a sphere and a line is used to represent the 10 last poins in This results in a continuous animation of the buses movement.

The user-interface gives the option to play and stop the animation. When the animation is not running, the users can move the time slider to a point of interest in time and visualize a kind of snapshot of the transportation system at that time. There is also a listbox with all the available routes to visualize. The user can select the route of interest and visualize the dynamics for that particular route. The bus route being visualize is shown in an information box located at the top right corner of the window. The current number of buses being visualized is also shown in this box. The interface lets the user navigate the visualization from different viewpoints by changing the camera perspective in a 3D space.

technologies used:   processing+json, data visualization