Creating Digital Graffiti at Samsung KX: Tangible Interaction and BlackTrax

Samsung 2Located in Vancouver, Canada, Tangible Interaction’s footprints are found throughout the city in the form of public artworks displayed for the 2010 Winter Olympic Games, Science World, Capilano Suspension Bridge, and the Vancouver Aquarium. As an interactive art installation studio, Tangible’s mission goes above and beyond: “Reigniting people’s sense of wonder is at the heart of our design. Our pieces evoke curiosity and playfulness, fostering indelible connections through striking experiences and memorable moments.”

The studio was founded by artist Alex Beim, whose creative work in Montevideo, Uruguay resulted in the first graphic design magazine in the country, paving the way with his major contributions to the design community in South America. Beim left the world of 2D design to explore the possibilities in interactivity, beginning the start of a new journey in 2006 in the form of Tangible Interaction Design, one of the only companies of its kind in Canada.
Under his creative direction, Tangible’s endeavors are carried out by a multidisciplinary team with expertise in a myriad of fields, including graphic design, industrial design, sound design, electronics engineering and software development. Since its foundation, the team has become a global company, working alongside brands such as Ford, ESPN, Heineken, Adidas and MTV, as well as entertainers including the Blue Man Group, Cirque du Soleil, Green Day and Coldplay.

Among Tangible’s range of experiential products is the Digital Graffiti Wall: an original concept created in 2007 with the goal “to bring people together with a fun, hands-on, interactive experience where anyone can grab a digital spray can to create art.” Since its conception, the Graffiti Wall has appeared in a host of events by the likes of Chanel, Facebook, Apple, Google, and now, Samsung. For this Graffiti Wall installation, Tangible was approached by agency Cheil Worldwide and, together with their creative team, the two companies worked to define and finesse what would become Galaxy Graffiti.

Galaxy Graffiti at Samsung KX
Spanning 20,000 square feet, the new Samsung KX store at the Coal Drops Yard in King’s Cross, London is an experience space that combines the best of local culture and innovation or, in the words of Y. H. Lee, Global CMO of Samsung Electronics: “more dynamic, flexible locations where exploration is endless, and Samsung KX is a place where infinite possibilities are made real.”

Inside the space, the Galaxy Graffiti wall stands out immediately to visitors and passersby, marked by a 10-meter wide LED screen showcasing a range of iconic London backdrops. Based on the King’s Cross metro station and the famous graffiti tunnel of London’s Leake Street, these 3D-animated digital canvases were custom-designed by Tangible for Samsung KX. Next to the dynamic backdrop of an animated London, visitors could reach for one of several “spray cans”, each equipped with Samsung Galaxy S10 phones with various colors and brush sizes to choose from, made possible through the custom app created by Tangible. Next, with a simple click and hold of the “spray button”, they could leave their mark on the Galaxy Graffiti LED wall for a fun and interactive experience that is at once simple and impressionistic.

The feeling of recreating real-time graffiti art on a massive digital canvas is nothing short of magic, which meant that the very best minds had to be put on the task.

The Quest for Live Tracking
In search of a perfect live-tracking solution that would accomplish this magical feat with minimal fuss, it was Beim who first spotted the potential of BlackTrax while browsing through Instagram. As soon as they reached out to BlackTrax, the Special Projects Team comprised of Dekkar Densham and Navdeep Hayer took over with enthusiasm for a custom challenge and, working closely with the Tangible team led by Project Manager Mark Olson, began to layout the challenges and brainstorm the possibilities.

After some testing at BlackTrax’s in-house studio at CAST HQ in Toronto, the two teams landed on a plan for what would become the final setup as it currently stands in the Samsung KX space. Working with a much smaller area than they were used to, the BlackTrax Special Projects Team had to consider all the angles of coverage that would provide the most realistic level of interactivity for visitors. Due to architectural and aesthetic constraints, the placement of BTSensors initially posed a series of challenges: For instance, in a typical BlackTrax installation, BTSensors would be hung in the air around a tracking area with a view from above. For Samsung, however, this was not an option due to the size and placement of the LED screen. After working with several possible solutions, the team finally settled on a custom camera design consisting of 10 ground-mounted and 6 ceiling-mounted BTSensors.

With that issue resolved, the team then moved on to the next challenge: accounting for multiple (four or more) participants taking part in the experience at once, which could lead to occlusion from the BTSensors to the spray cans being tracked. To overcome this, the team placed the ground-mounted BTSensors strategically close together so that the cans near the bottom of the screen would always be tracked, even in the presence of multiple spray cans being used in the same area simultaneously.

Another challenge in this project was that of latency: as with any application involving LED walls, inherent latency inevitably becomes a concern as they are not all built for real-time use. The initial suggested approach was to use a capture card to capture the game running on the Graffiti server, then output it to the LED Screen through a media server. In testing, however, this path led to an undesirable amount of latency, so a video switcher was used instead to enable the Graffiti server to connect direct to the screen for the Graffiti experience. This led to the best user experience where at the click of the spray can paint button, the virtual spray happened almost instantaneously on the wall.

The resulting BlackTrax setup consisted of 16 BTSensors placed around the space, 10 BTBeacons – one for each spray can, and 3 Stringers embedded into each spray can for optimal tracking. In order to perfectly fulfill Tangible and Samsung’s vision, three-point rigid bodies were created in BlackTrax on each spray can to provide the most accurate 6D positional and rotational information. This allowed for a realistic spraying experience that reflected the tilting of the can at different angles relative to the screen, affecting the behavior of the virtual spray in real time.
With covert placement of Sensors, customized Stringer colors and built-in Beacons, the BlackTrax system remained inconspicuous inside the store, keeping the Galaxy Graffiti wall and Tangible’s creations as the main attractions.

Opening Day
The Samsung KX space opened its doors to visitors on July 31st, 2019. Dekkar Densham, Team Lead of Special Projects at BlackTrax, visited the site soon after its opening: “It was great to see artists and non-artists alike come together at the Galaxy Graffiti space to take advantage of this exciting and accessible technology. The experience was simple, straightforward and required no explanation: people came in, saw the graffiti wall, grabbed a spray can, and just started painting.” The cumulative efforts of Samsung, Cheil, Tangible and BlackTrax remain on display at King’s Cross, London for all to see and play around with. Olson and his team at Tangible are “always looking to create installations that bring people together,” and this graffiti was the perfect example of the type of realistic experiences that can be dreamed and accomplished when artists and technologies work together.

With ambition, creativity and technology working hand in hand, the results can be stunning. In addition to displaying the potentials of artists and technologies, interactive displays and installations convey a sense of what it means to be a community in the modern age, and BlackTrax is proud to have played an instrumental part in realizing this vision.