What is 4d printing?

4D printing, a process where 3D-printed objects transform in response to external environmental stimuli, such as heat, wind, water, and other forms of energy. 4D creates objects that can alter their shape and perhaps even their functions over time.

4D printing requires a commercial 3D printer and a smart material. A smart material can be a hydrogel or shape memory polymer. A hydrogel is a 3D hydrophilic polymer that can hold a large amount of water while maintaining its structure. A shape memory polymer, meanwhile, is a material that can return to its original shape after getting deformed. The 3D printer turns the smart material into your desired product.
4D printing uses the 3D printer to change the structure of a smart material to the user’s desired shape. An example would be 4D-printed shoes. While they may look like your typical pair of footwear, their soles follow your feet’s unique structure, making them fit you better over time.
Self-repair: 4D-printed plumbing pipes, for instance, can change their diameter depending on how much water flows through them. As such, they can potentially repair themselves if they crack or break because they can respond to environmental changes.
Self-assembly: 4D-printed building materials, which can change their shape, will take do-it-yourself (DIY) construction to the next level. Imagine being able to print custom shapes to instantly build a bridge. You won’t need to spend more on labour costs so long as the structures are deemed structurally sound by engineers.
Self-adjustment: 4D-printed clothes can be made of materials that adjust to the current weather or climate. Imagine how much money people would be able to save buying only a single set of clothes for all seasons.