A Robotic Hand That Detaches and Crawls
Researchers at EPFL built a symmetric robotic hand that detaches from its arm, crawls to unreachable objects, and reattaches, all autonomously.
Most robotic hands are fixed to an arm, limiting their reach. Researchers at EPFL and MIT designed a detachable, symmetric hand that crawls beyond that boundary, grasping objects and returning on its own.
What does a crawling robotic hand do?
This robotic hand attaches to a standard robotic arm for normal manipulation tasks, then detaches to crawl across surfaces independently. Using symmetric, reversible fingers, it grasps objects from either side, stacks them on its back, and reattaches to the arm once it returns, no repositioning required.
Why merging grasping and locomotion changes robotics
Traditional robotic systems separate manipulation from movement: a robotic arm handles objects while a mobile platform provides transportation. These independent modules increase cost, weight, and control complexity. This hand collapses both functions into a single platform by sharing actuators and control infrastructure across grasping and crawling — reducing energy consumption and mechanical overhead.
The practical implications are significant. In warehouse environments, the hand can crawl into dense shelving to retrieve items that fall outside a stationary arm's workspace. In disaster response, it navigates confined spaces, underneath debris or inside narrow equipment, where larger robots cannot fit. Industrial inspection tasks in pipes or complex machinery become viable without deploying separate crawler units.
The symmetric finger architecture also improves reliability. If the hand flips over during crawling, its reversible joints allow it to stand upright from any orientation without human intervention. Experiments showed that symmetric configurations outperform asymmetric ones by 5–10% in crawling distance, while keeping 4 to 5 fingers as the optimal count, beyond that, added fingers increase self-collision risk and slow the gait. This design represents a practical route to robotic systems that are compact, self-sufficient, and capable of operating in environments where conventional arm-hand combinations fall short.