The Karlspreis Interactive Exhibit ("Karlspreisstele")

The Exhibit

The Karlspreis Interactive Exhibit ("Karlspreisstele") lets you discover the Charlemagne Prize ("Karlspreis"), its recipients, and the reasons for each award at four interactive wall displays in the historic Aachen City Hall where the annual award ceremony takes place.

The display on the first floor in the stairwell answers frequently asked questions about the Charlemagne Prize. On the next landing, you will find the two main displays that let you explore all of the over fifty Charlemagne Prize laureates. Tap on one of the portrait photographs to see the biography, excerpts from the speech, the reasons for the award, or a video of the ceremony. Particularly informative is the word cloud above each portrait. It shows the results of an automatic analysis of the speech, highlighting words that appeared frequently in it (automatically excluding trivial words like "the" or "and"). This suggests the hot topics of each speech and allows for interesting comparisons among laureates and their word clouds. The wheelchair-friendly and height-adjustable display on the ground floor combines the information about the Prize and its recipients.

The above four exhibits can be visited during regular opening hours of the Aachen Town Hall. We also provided the Charlemagne Prize Foundation (Karlspreisstiftung) with a version of the exhibit for display on other occasions, and we have one copy of the exhibit set up at our lab for development, testing, and demonstrations. We update all exhibits with information about the new award recipient each year.


The original exhibit was deployed in 2008 and was on permanent public display for ten years. It was based on a Java application running on an Apple computer attached to a portrait-mode 32" touchscreen. In 2018, we completely redesigned the exhibit. It is now powered by a Raspberry Pi 3 B+ single-board computer and a combination of a 32" display with a capacitive touch layer on top. The software is based on HTML 5 and CSS 3 for laying out the portraits, texts, and buttons. We use JavaScript to respond to the user's touch input. The word clouds are based on histograms of the words appearing in a given speech. They are laid out using a randomized approach. Starting from a center text block, other text blocks are randomly attached to its borders while preventing overlaps. This makes for a compact, yet interesting visual appearance.


The display is currently maintained by Oliver Nowak, M.Sc.


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