You're probably familiar with the push-to-open mechanism used by fancy cabinets. Pressing the cabinet door pushes an internal latch inward, past a "trigger point" like a cam or notch that had been holding it in place. This then allows a spring behind the latch to release and push outwards, opening the cabinet door. If you need help visualizing it, here are some animated cutaways of different variants:The mechanism's action is somewhat counterintuitive—you push something away from you, to get it to move toward you—but most people grasp it instantly.Now a collaboration at AMOLF and ARCNL, two Dutch research institutes, have developed the opposite mechanism: Something that you pull in one direction, which causes it to contract in the opposite direction. "This surprising behavior," they write, "defies conventional understanding of materials and opens up exciting applications in soft robotics, smart devices, and vibration control systems."Their mechanism consists of three components:Once these components are interconnected, they behave like this:Here's what they do in an opposing horizontal configuration:For applications, the researchers suggest the following:- One-way sliding motion without motors or electronics — potentially useful in soft robots that need to move forward without slipping backward, such as medical robots navigating through the body. - Materials that switch stiffness on demand — ideal for wearable exosuits or prosthetics that need to be flexible during movement but stiffen instantly for support or safety. - Structures that dampen excessive vibration all by themselves — potentially lifesaving in systems like airplanes, wind turbines, or even buildings in earthquake-prone areas. The researchers refer to the phenomenon as "countersnapping." If you're interested in the science behind it, the team lays it all out in a research paper here. There are also some more demonstrations in the video below. #dutch #researchers #develop #opposite #pushtoopen