ZipFold: Modular Actuators for Scaleable Adaptive Robots
A new modular actuator system enables robots to transform between flexible and rigid states on demand.
A team from MIT's Computer Science and Artificial Intelligence Laboratory (CSAIL), led by researchers Niklas Hagemann and Daniela Rus, has introduced ZipFold, a breakthrough in modular robotics. The system centers on a simple, easy-to-fabricate actuator made from flexible 3D-printed plastic strips. Through a compound folding and 'zipping' mechanism, these strips can reversibly transform into square-section deployable beams. This allows each module to achieve a continuous, smooth transition between two key states: a compact, flexible form and an expanded, quasi-rigid structure. The actuation method is notably simple, enabling precise control over stiffness and scale without complex, bespoke hardware.
By connecting multiple ZipFold modules, engineers can construct larger, scalable robotic assemblies capable of diverse shape and stiffness transformations. This addresses a major limitation in current shape-changing robotics, which often relies on custom, application-specific mechanisms that are difficult to reconfigure or scale. The paper details the mechanical characterization of the actuator and demonstrates its practical application in an integrated system: a four-module adaptive walking robot. This proof-of-concept shows how the technology can enable a single robot platform to adapt its physical properties—like leg stiffness and posture—to navigate evolving environments and perform varied tasks, moving beyond static, single-purpose designs.
- Core actuator is a 3D-printed plastic strip that folds/‘zips’ into a rigid beam, enabling reversible stiffness and scale changes.
- Demonstrated in a functional four-module walking robot, proving scalability and real-world application for adaptive locomotion.
- Solves a key robotics challenge by replacing bespoke, hard-to-scale mechanisms with a simple, reconfigurable, and fabricable modular system.
Why It Matters
Enables the creation of versatile, multi-purpose robots that can physically adapt to dynamic real-world tasks, from search-and-rescue to exploration.