New Programmable Foam Lattice Enables 75 Million Robot Configurations, Mimicking Biological Tissues

Lausanne, Switzerland – Researchers at EPFL’s Computational Robot Design and Fabrication Lab (CREATE) have unveiled a groundbreaking programmable foam lattice that allows 3D-printed robots to emulate the intricate blend of soft and rigid tissues found in nature. This innovation, detailed in a recent publication in Science Advances, promises to revolutionize the design of lightweight, adaptable robotic structures. The technology can achieve over 75 million distinct configurations from a single material.

The core of this advancement lies in a simple foam material composed of individual units, or "cells," that can be programmed for various shapes and positions. As stated in a tweet from TechXplore, this "programmable foam lattice enables 3D-printed robots to mimic the complex interplay of soft and rigid tissues, achieving lightweight, adaptable structures with millions of possible configurations." This approach overcomes previous limitations of multi-material 3D printing, which struggled to continuously control properties like stiffness across a robotic structure.

Led by Josie Hughes, the CREATE Lab team, including postdoctoral researcher Qinghua Guan and Ph.D. student Benhui Dai, developed two primary cell types: body-centered cubic (BCC) and X-cube. These can be continuously blended through "Topology Regulation" (TR) or superimposed using "Superposition Programming" (SP). This dual programming allows for an unprecedented range of mechanical properties, from tissue-like compliance to rigid, load-bearing capabilities.

To demonstrate the technology, the team constructed a musculoskeletal-inspired elephant robot. "We used our programmable lattice technique to build a musculoskeletal-inspired elephant robot with a soft trunk that can twist, bend and rotate, as well as more rigid hip, knee, and foot joints," said Qinghua Guan. This model showcases the lattice's ability to create complex, bio-inspired movements and structures using a single material.

The programmable lattice offers significant advantages for future robotics. Ben Dai noted that the approach "enables the continuous spatial blending of stiffness profiles and allows for an infinite range of blended unit cells," making it ideal for replicating organs like an elephant trunk. Furthermore, the open foam structure boasts a high strength-to-weight ratio, is well-suited for motion in fluids, and can integrate sensors directly within its framework, paving the way for more intelligent and efficient robots.