What’s under the hood?
For the longest time I’ve been meaning to share how we built the Defining Moments Discovery Wall — a large and delightful interactive timeline located in prime position at the entrance to the Museum’s Cafe.
Possibly due to its location, but also because it's such an engaging experience, we often receive enquires about what’s under the hood. People want to know more about the technology and hardware used to develop this installation.
Before I launch into the technical details, a few words about why we developed the timeline and what it does.
What is the Defining Moments Discovery Wall?
In 2016 the Museum redeveloped its main hall, which became the Gandel Atrium. A central component of the Atrium is a display from the Defining Moments in Australian History project, which aims to stimulate public discussion about profoundly significant Australian events.
The Discovery Wall provides entertaining and engaging pathways into a selection of Defining Moments content. Given that each defining moment occurred at a specific point in Australian history, it made sense for the main interface to be a timeline.
In the Defining Moments Discovery Wall an organic ribbon extends across the length of the screens. Image tiles representing each defining moment are clustered together around relevant time periods. Visitors can tap on an image tile to find out more about the selected moment. Tapping on a topic or place tag within a moment causes lines to appear on-screen and connect to related moments.
There are also 10 images that activate an animation and launch a ‘did you know’ factoid or quiz question.
Visitors can vote for their favourite moment and find out how others have voted through real-time charts and diagrams.
Suitably impressed? Great. Now, here’s what the wall is made of.
The front-end touchscreen application
The application is built in openFrameworks, an open source C++ based openGL library. It interfaces with the touchscreen driver using the universal TUIO implementation to translate touch coordinates to on-screen positional data.
The application integrates with a Content Management System (CMS) for deploying and synchronising updates, using standard JSON-formatted data. Updates are drawn daily from the CMS. The application stores a local cache of data and assets in case the connection is lost with the CMS. The touchscreen application logs usage statistics for analytical purposes, which can be viewed within the CMS.
The content management system
The system runs on a Ruby on Rails framework for Unix/Linux on a virtual server hosted locally at the Museum. A PostgreSQL database is used to store the app content. Asset files including images, videos and audio are saved on the same server. The front-end touchscreen application uses an updater script to call a JSON API endpoint from the CMS, compare the data and download recent changes.
The five-screen video wall is an LCD Video Wall LX55HDU MultiTouch MT32 from Planar. So far we’ve found this to be a robust solution for such a large-scale multi-touch interactive.
The application is running on a high spec Dell Precision Rack 7910 computer with an AMD FireProW9100 video card to help cope with such a resource-intensive application. The operating system is Windows 8.1.
So there you have it, a brief overview of the creative and technical approach for our popular Defining Moments Discovery Wall. A shout-out to the folks at Lightwell who were responsible for the design and development of this fun interactive experience. Come in and try it out!