Xstrings: Automated Manufacturing of Cable-Driven Objects with 3D Printing

Researchers at MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) have developed a method to create cable-driven mechanisms using a single 3D printing process. The technique, called “Xstrings”, combines a design tool with an additive manufacturing method to produce bionic robots, sculptures, and interactive fashion more efficiently. The innovation will be presented at the Conference on Human-Computer Interaction (CHI 2025).

Cable-driven mechanisms operate through integrated strings that enable complex movements through controlled tension. Traditionally, assembling such structures has been a time-consuming manual process. However, Xstrings integrates cables, joints, and mechanical components directly during 3D printing, reducing production time by up to 40% compared to conventional assembly methods.

“Our innovative method can help anyone design and fabricate cable-driven products with a desktop bi-material 3D printer,” said Jiaji Li, a postdoctoral researcher at MIT and lead author of the study.

The system precisely controls movement types such as bending, twisting, and contracting. Users can define an object’s motion through specialized software by selecting predefined movement patterns. One key application is a robotic gripper, where parallel cable routing enables synchronized finger movements. Xstrings also opens up new design possibilities for artistic and fashion applications, such as dynamic sculptures or clothing with adjustable, moving elements.

“The Xstrings software can bring a variety of ideas to life,” says Li. “It enables you to produce a bionic robot device like a human hand, mimicking our own gripping capabilities. You can also create interactive art pieces, like a cable-driven sculpture with unique geometries, and clothes with adjustable flaps. One day, this technology could enable the rapid, one-step creation of cable-driven robots in outer space, even within highly confined environments such as space stations or extraterrestrial bases.”

The Fused Deposition Modeling (FDM) process is used for manufacturing, where plastic is melted and deposited layer by layer. Xstrings enables horizontal integration of cables within the structure, improving mechanical load distribution. Material tests show that embedded cables remain functional for over 60,000 cycles. Further research will focus on incorporating more durable materials and three-dimensional cable routing.

The researchers see significant potential for Xstrings in space applications, where compact, easy-to-assemble mechanisms are essential. Through automated printing, complex robotic systems could be manufactured directly in confined environments, such as space stations or extraterrestrial habitats. The project was supported by research grants from Zhejiang University and the MIT-GIST program.