Sprayprinter’s robot in action (GIF by the author for Hyperallergic, via Sprayprinter)

Towering over the eastern Estonian city of Tartu is a lean chimney stack that features a 98-foot-tall mural of a girl holding a potted plant in her cupped hands. The image required 14 hours of labor and 40 cans of spray paint but zero manpower: it was rendered by a little robot that scuttled across the chimney’s surface with five cans of paint on its back — a device its inventors hope will revolutionize the mural industry.

The mural in Tartu, Estonia (photo courtesy Sprayprinter)

The robot was invented by Mikhel Joala, co-founder of SprayPrinter, a tech company focused on redesigning traditional methods of spray-painting. Previously, it released its namesake devise, a handheld printer that connects to your phone via bluetooth to let you spray-paint a digital image onto a wall, pixel by pixel.

The printer that embellished the Tartu chimney, completed at the end of last month, is intended for much larger-scale works. A prototype for the company’s latest vision, it features a printhead consisting of five Spraypainters that work simultaneously to produce a full-color image, following instructions from a computer on where to paint and what color to spray.

The mural in Tartu, Estonia (photo courtesy Sprayprinter)

“Basically, the image file that the computer read was a text file consisting of coordinates and laser power values,” Aet Rebane of Sprayprinter explained to Hyperallergic. “The computer sent lines of code (called G-code) one by one to the main controller that executed the commands. Instead of a laser, we had a five-color printhead … Another controller measured the laser control pin for different pulse widths that ranged from about zero to 1,000 microseconds. Then these values were wirelessly sent to the printhead to trigger different colors, everything happening about 100 times per second.” The final image consists of many dots two centimeters in diameter that were stamped closely side by side, rather than solid strokes.

For the Tartu test run, the bot was hooked up to cords so it could securely roll up and down the column. The resulting mural is less than a third of the maximum height of artworks the device can produce: Sprayprinter has engineered it to paint murals up to 328 feet, and the company plans to attempt to break the world record for largest mural.

Spray-painting in action on the chimney stack (photo courtesy Sprayprinter)

It’s also hoping to launch a limited run of 50 to 100 printers at the end of the year. Sprayprinter’s target audience is not graffiti writers but professional street artists who receive commissions from building owners and would like to cut down on the time spent on brushwork. Rebane says Sprayprinter’s own team of muralists has so far collaborated with local governments, hotel owners, and, unsurprisingly, real estate developers.

This isn’t the first-ever painting robot, though it’s certainly the only one with the ability to realize images so quickly on such a large scale. Software developer Pindar Van Arman created bitPaintr, which runs on artificial intelligence to produce portraits based on uploaded photographs. And there’s e-David, a welding robot with a paintbrush that uses machine learning to replicate pictures. Sprayprinter is intended to replace muscle more than replicate creativity, and although for many artists painting is an invaluable part of the process, others will surely appreciate the mechanical help.

Claire Voon

Claire Voon is a former staff writer for Hyperallergic. Originally from Singapore, she grew up near Washington, D.C. and is now based in Chicago. Her work has also appeared in New York Magazine, VICE,...