4D-printed robot self-assembles into a tube and rolls up hills

A simple tube-shaped “4D-printed robot” can roll uphill, carry a load and navigate an unpredictable landscape.

Wei Feng at Tianjin University in China and his colleagues designed the robot, which is built from a flat rectangular sheet of 3D-printed liquid crystal elastomer. When the surface that this sheet is placed on is heated above 160°C, the sheet self-assembles by rolling into a tubular form, taking on the appearance of a piece of hollow, spiral spaghetti.

This change in shape over time adds a fourth dimension to the construction process, making this what the researchers call a 4D-printed robot.

The …