The foldable robots could also be used for seabed explorations. (Representative image)

Scientists have built the first foldable walking robot that pops up when deployed, and could be used for future space missions as well as seabed exploration on Earth.The robot, which the researchers call DeployBot, is assembled from eight modules: four for the body and one for each of the four legs.In their folded state, the modules lie flat, and after they are deployed they pop up into roughly a square shape.The modules are made of both rigid and flexible materials and contain embedded magnets that connect and lock multiple modules together.A shape memory alloy wire running through the square frame of each module is responsible for deploying and folding the modules, which takes several seconds but can be done repeatedly."The main advantage of this modular robot is robustness in various environments due to lack of mechanical systems such as motors and gears," said Sung-Hoon Ahn from Seoul National University in South Korea."Thus, problems facing motor-based robots, such as sealing and lubrication of mechanical systems in water or space environments, are not a problem for the smart actuator," Mr Ahn was quoted as saying by 'Phys.org'.The robot walks when an electric current is applied to shape-memory alloy wires embedded in its frame. The current heats the wires, causing the robot's flexible segments to contract and bend.

Sequentially controlling the current to various segments in different ways results in different walking gaits.No motors are required for the robot to move, researcher said.