Now robots that can change form have a role to play beyond the traditional helper roles Reuters

Fact and fiction seem to merge with the latest material developed by scientists at Massachusetts Institute of Technology (MIT) and others. The phase-changing material paves the way for deformable surgical robots that could move through the body to reach the target location without causing any damage.

We could also see robots deployed at scenes of disaster, wriggling their way in and out of rubble looking for survivors.

The material was built from wax and foam by Anette Hosoi, a professor of mechanical engineering and applied mathematics at MIT, and her former graduate student Nadia Cheng, along with researchers at the Max Planck Institute for Dynamics and Self-Organization and Stony Brook University.

As can be imagined, a robot has to have sufficient strength, while being flexible, if it is to push through heaps of rubble or break any barrier. Equally challenging for the team was how to control a soft structure and predict what shapes it will take. That was why they picked a material that could switch from soft to hard – a foam structure coated in wax. The foam ensured pliability and the wax allowed for modification under heating. The wax coating could also be replaced by a stronger material, such as solder.

Electricity was run through a wire to heat up the wax when required. Heating the wax allowed for repair, rendering a certain self-healing ability to the structure.

Using 3D images, they were able to analyse the structure and study the position of each pore and strut on the foam.

The team is now investigating the use of certain fluids that can be made to switch from a soft to a rigid state with the application of a magnetic or electric field.

The paper was published in the journal Macromolecular Materials and Engineering. The work was a result of the Chemical Robots programme of the Defense Advanced Research Projects Agency (DARPA).