You could have them living in the world with you and you could make them change into whatever you need, when you need it

Prof Daniela Rus

Eventually, the researchers hope to use thousands of microscopic units to make infinitely flexible machines, fit for any task.

The scientists behind the research believe future generations of robots are more likely to be mutating machines, rather than the single-function devices becoming common today.

But developing the control systems that would co-ordinate all the units that make up a morphing robot is going to prove a major technical challenge.

Form and function

Domestic robots are starting to appear but most tend to be fixed-function devices: robotic vacuum cleaners cannot cut your grass, and autonomous mowers will shred your shagpile rather than spruce it up.

Now, Professor Daniela Rus and colleagues from Dartmough College in New Hampshire, US, are trying to make robots much more useful and adaptable by building them out of smart building blocks instead of wheels, motors, grippers, legs and the like.

"We believe in the paradigm of self-configuring robots as the way to do robotics in the future, 20 to 50 years from now," Professor Rus told News Online. "Fixed-architecture robots are too limited."

"If you have modular, reconfigurable robots, you could have them living in the world with you and you could make them change into whatever you need, when you need it," she said.

Eventually, the blocks will be small enough to make the robot form tools such as grippers and legs.

At the moment, Professor Rus and her colleagues are experimenting with large building blocks that are a few centimetres square. These blocks have all the basic qualities of a smart unit.

Their faces can be extended or contracted on demand, they have an onboard processor to communicate with other units and they can lock to or disconnect from fellow units as needed. Robots made from the smart blocks will likely inch along like caterpillars.

Complete control

With potentially thousands of smart units in a morphing robot, centralised control systems will not be able to make the robot morph fast enough.

The individual units will only have knowledge about their immediate vicinity and Professor Rus says it is hard to see how they can be made to collaborate to create a new robotic form.

She suspects that a process of top-down planning that "cascades" the process of form-changing will be needed to make the system change shape quickly.

Eventually, Professor Rus and colleagues hope to make tiny replicas of the bulky, centimetre-square blocks and create radically deformable robots.

Already, the group is collaborating with other academics using such micromechanical systems to make smart surfaces that can manipulate objects placed on them.