1. INTRODUCTIONWe have all heard of 3D printing, but have you heard of 4D printing? Probably not. 4D printing uses the same technologies as 3D printing, but with a slight change, objects printed in the fourth dimension have new capabilities. 4D objects will be able to change their shape or appearance over time. 4D printing allows you to think outside the box, perhaps even producing weapons that can assemble themselves. One of the limitations of 3D printing, in which a printer deposits successive layers of materials like plastic to create objects as diverse as guns and toys, is that assembly is often necessary, but the 4D printing offers the possibility of creating objects that literally come together. . Do you have the data taken into account: http://www.livescience.com/40888-army-4d-printing-grant.html2. ABOUT 4D printing offers the possibility of creating things that literally come together on their own. The technology could also create objects that last longer than their 3D printed counterparts and adapt on command to specific conditions. 4D printing involves using a 3D printer to print self-reusable programmable hardware. For example, you have a non-living object that can change shape and behavior over time, much like a robot but without a microprocessor, in fact something that looks like plastic. Skylar Tibet's, the man who came up with the whole idea, has become even more fodder; he created a programmable sheet material. It looks like plastic which, in combination with water, could change the shape of the cube. And the cube is just the beginning. It will be a million shapes. This could be very useful, not only on Earth, but also in orbit. This idea could change the world and make a living from it. Imagine if you could simply print your furniture. A...... middle of paper ...... outside.3. HOW IT WORKS The idea was to improve the 3D printer with special technology, a single printer, with multi-material characteristics, can transform any 1D strand into 3D shape, 2D surface into 3D shape or itself. transform from one 3D shape to another. The form of 3D technology is the basic mode of 4D. Objet Connex multi-material technology forms an important part of its 3D printing work and is widely used in this new process. Connex multi-material technology allows researchers to program different material properties into each of the different particles of the designed geometry and exploit the different water absorption properties of the materials to enable the self-assembly process. With water as activation energy, this technique promises new possibilities for integrating programmability and simple decision-making in non-electronic materials..