Robots can do a lot of things, but did you know that they also have the capacity to create art? Scientists at Dartmouth College have created a robotic artist that can spray paint giant murals.

The "smart" spray can system is actually a new twist on computer-aided painting. This particular method, which uses computers, originated in the early 1960s.

Painting murals with spray paint can take a lot of time and effort when it comes to covering entire walls of buildings and other large surfaces. In this case, the researchers wanted to create a way to help non-artists create accurate reproductions of photographs as large-scale murals using spray painting. That's why they created a computer-aided system that uses an ordinary spray paint can and then tracks the can's position relative to the wall or canvas to recognize what image it "wants" to paint.

So, how does it work? A non-artist can wave the pre-programmed spray can around on the canvas. Then, the system operates the spray on/off button to reproduce the specific image as a spray painting. In other words, the can knows what to paint and what not to paint.

The robotic spray can prototype includes two webcams and QR-coded cubes for tracking. It also has a small actuation device for the spray can, which is attached via a 3D-printed mount.

Paint commands are transmitted via radio directly connected to a servo-motor operating the spray nozzle. The real-time algorithm operating on a nearby computer determines the optimal amount of paint of the current color to spray.

"Typically, computationally-assisted painting methods are restricted to the computer," said Wojciech Jarosz, co-author of the new study. "In this research, we show that by combining computer graphics and computer vision techniques, we can bring such assistance technology to the physical world even for this very traditional painting medium, creating a somewhat unconventional form of digital fabrication. Our assistive approach is like a modern take on 'paint by numbers' for spray painting. Most importantly, we wanted to maintain the aesthetic aspects of physical spray painting and the tactile experience of holding and waving a physical spray can while enabling unskilled users to create a physical piece of art."

The findings are published in the April 2016 issue of the journal Computers & Graphics.