Detail, quilted acoustic panels
Tsz Yan Ng Detail, quilted acoustic panels

This article first appeared in ARCHITECT.

"This project opens new territory for a material that has connections to art, to architecture, and to the domestic space. This is a novel way of working with felt and it has many applications." —Juror Florencia Pita

Binding thermoplastic textiles was already familiar territory for Tsz Yan Ng, an assistant professor of architecture at the University of Michigan, so she turned to the newfound possibilities offered with needle felting, the age-old process whereby a barbed needle pushes through layers of fabric and, as it pulls back, entwines the threads and thus the layers, uniting the plies.

Ng wondered whether she could integrate this low-tech process with robotic manufacturing to create a more efficient way to produce complicated needle felting. But getting the robotics to execute the inherently simple actions was deceptively difficult. “A lot went in to tuning the process, and making the needle bind correctly,” she says. “We went through a lot of trial and error.”

The result, developed by Ng and her team at the Taubman College of Architecture and Urban Planning’s Digital Fabrication Lab, which includes director Wesley McGee and research associate Asa Peller, is an additive process somewhat analogous to 3D printing: A robotic head equipped with a needle is fed a strip of felt that it then lays out and attaches onto a foam substrate.

Robotic needle felting process on an acoustic panel
Tsz Yan Ng Robotic needle felting process on an acoustic panel

“Integration into a robotic process not only enables precision and speed in manufacturing but also extends needle felting as a 3D process, especially for surfaces with complex geometries,” Ng and her team wrote in their submission. Because the robot arm can move in multiple directions and angles, it can create complicated fabric topographies all without thread or glue, making the process environmentally friendly and visually captivating.

Ng focused on three methods of needle felting: quilting, or the binding of two similarly sized felt sections; shiplap, in which entire felt strips successively overlap; and shingling, in which individual felt pieces are laid down, each partially over the previous. Depending on the method deployed, the robot can complete up to several inches a second.

2x6 acoustic panels showing shingle (left) and shiplap (right) needle-felting techniques
Tsz Yan Ng 2x6 acoustic panels showing shingle (left) and shiplap (right) needle-felting techniques
Wavy shiplapped pattern with texture created by a "lift" of the curved lines
Tsz Yan Ng Wavy shiplapped pattern with texture created by a "lift" of the curved lines

Even without glue or thread, the binding between each layer is incredibly strong. “There are hundreds of fiber interactions per square inch,” Ng says.

Possibilities for the technology abound, she adds. “If you look at most acoustic treatments, they’re pretty generic,” she says. “So there’s a lot of potential there.” The process can also bind conventional felt over a substrate of insulation, creating a finished insulative surface. A third application would be the incorporation of needle-felted fabrics into furniture or wall treatments.

And Ng is investigating what happens when different types of felt, bound together, are heated. “Once baked, felt creates a different curvature and form with a slight stiffness—and that has all sorts of potential,” she says. “Right now, we’re testing it to see how far we can push it as a structural element.”

Baking process with composite test panels
Tsz Yan Ng Baking process with composite test panels
Left to Right: Baked panels with 30-degree front and back curvature; 45-degree curvature, and single-sided, curved shiplapped panels
Tsz Yan Ng Left to Right: Baked panels with 30-degree front and back curvature; 45-degree curvature, and single-sided, curved shiplapped panels
Felted poof with a complex geometric surface
Tsz Yan Ng Felted poof with a complex geometric surface

Project Credits
Project: Robotic Needle Felting
Design Team: University of Michigan Taubman College of Architecture and Urban Planning, Ann Arbor, Mich. . Tsz Yan Ng, Wesley McGee, Asa Peller (project team); Rachel Henry (research assistant); Jared Monce, Drew Bradford, Carlos Pompeo (production assistants)
Funding: 2018 Taubman College’s Research Through Making grant program, University of Michigan, and the University of Michigan Office of Research’s Small Scale and Preliminary Projects grant

Note: This article has been updated since first publication.

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