You've no doubt seen string art before – it consists of images created by running thread between pins on a board. Well, scientists at Austria's Vienna University of Technology (TU Wien) have recently created an algorithm that allows a robot to recreate existing images in string-art form.

The camera-guided robot, which is a commercial industrial model, creates its masterpieces on a board with a ring of 256 hooks on it. That ring is 63 cm (24.8 inches) in diameter.

Using a program on the computer that controls the robot, users input an image such as a photo of a person's face. A custom algorithm within that program determines the manner in which the robot should wind a single continuous thread between the hooks on the board, in order to best reproduce that image.

For every thread line in the string-art creation, the algorithm can choose between running the thread from the left or right side of any one hook, to the left or right side of any other. According to the researchers, this allows for "more possible variants than there are atoms in the observable universe."

A portrait of computing pioneer Ada Lovelace, recreated by the string art robot

The system takes anywhere from 2 to 5 hours to create a single image, using a strand of thread measuring 2 to 6 km (1.2 to 3.7 miles) in length. And while even more hooks could have been used on the board, calculations indicated that any improvements to the finished image would be marginal.

"Even though our robot produces pretty pictures, our work is of course not an art project," says Przemyslaw Musialski, head of TU Wein's Computational Fabrication group. "Ultimately, we want to show how particularly difficult technical problems can be solved. In the String Art project, we work with methods that will play an important role in digital fabrication in the future."

A paper on the research has been published in the journal Computer Graphics Forum. The robot can be seen at work, in the video below.

Source: TU Wein