Researchers at the Carlos III University of Madrid have developed a 4D printer that allows three-dimensional structures to be printed with the ability to change their properties or geometry in response to external magnetic fields, or the ability to modify their electrical properties when deformed.

This technology is complex, since the material to be extruded goes from liquid to solid during the printing process. Therefore, it is necessary to understand the dynamics of the material to adapt the manufacturing process and obtain a material that is liquid enough to flow through the printer nozzle, but solid enough to maintain a specific shape. In addition, the research team has developed a new material concept that is capable of healing itself autonomously without the need for external action.

Limitless possibilities: the combination of intelligent materials in the UC3M 4D printer

The development of multifunctional soft structures opens up new possibilities in the biomedical field, such as the creation of soft robots, sensors and smart substrates that transmit signals to different cellular systems. This type of printing also makes it possible to design materials that change their shape or properties when activated by external stimuli, such as magnetic fields or electric currents.

The researchers have succeeded in printing three types of functional materials: those that change shape and properties in response to external magnetic fields; others with self-healing capacity; and others whose electrical properties vary according to their shape or deformation. With the first type of material, they have developed smart substrates to transmit forces and signals to cellular systems, so that they can influence biological processes such as cell proliferation or migration. These materials can also be used to design soft robots whose performance can be controlled by magnetic fields.

The combination of materials with self-healing capacity and whose electrical conduction properties vary with deformation opens up enormous possibilities in the development of sensors. In addition, these materials can be useful in the design of sensors that, attached to the human body, collect information about our movement from variations in electrical conductivity. Likewise, the self-healing capacity of the material allows the design of sensors with binary signals.

The interdisciplinary methodology developed by the researchers at the Carlos III University of Madrid combines theoretical and experimental techniques that allow them to build the printing device from scratch, both the physical part of the device (the hardware) and the computer programs that allow it to be controlled (the software). The results of this research have led to several registered patents.

To learn more about this advance presented by UC3M, the researchers of this project presented its most relevant aspects in a video.