Soft Robots Bend The Possibilities

Robots immediately bring up connotations of hard metal, whirling motors and precise movements. The rapidly developing field of 'soft robotics' is bending that notion by combining pneumatics, 3D printing, silicone rubber and the locomotion of jellyfish and octopi. Air or liquid is forced into specially designed rubber forms, following particular channels to bend the piece or make it rigid in a controllable manner. Who said you had to use metal to make a robot!


It's a new field and researchers are exploring new possibilities. The video below is of a simple 6-point gripper picking up an egg. On the up-facing side, air fills small cavities in each point whilst air is evacuated on the other side, creating enough force to grip the uncooked egg, lift it and gently return it again.

One exciting possibility is using conductive fluids like salt-water or lesser known compounds like Galinstan, a room-temperature liquid metal alloy made of Tin, Indium and Gallium. Soft robots that carry signals for sensors, or pick up signals themselves as antennas or conduct power are a very real possibility. Strain, stress, compression or force could be measure by such 'stretchable circuits'. Soft robotic hands could be given to those disabled people. If strong enough, it could be used to augment hand strength, although the materials themselves limit that application at the present moment.

The key use at the moment is fitting through small holes, going underneath objects or choosing the right colour to blend in with the surroundings. That is the aim of recent DARPA funding for the Whitesides Research Group at Harvard University. The future will likely be a combination of hard robotics and soft robotics, buttressing each other's inherent advantages and become more versatile.

Soft robots are easy to make - usually a CAD design, a 3D printer and silicone or rubber is all that is needed. If you have 15 minutes, I recommend watching this rapid-fire lecture by industrial designer and maker Matthew Borgatti. He describes in great detail what you need to do to create your own soft robot and waxes lyrically on Open Engineering and 3D Printing.