Nano limbs shape up to performing medical procedures

A titanium nickel alloy that changes shape when struck by a beam of energy is being used to create nanorobot arms and legs. These could allow nano-sized robots to manipulate molecules and materials as small as 100 atoms across, leading to the development of tiny devices for use in medical and other applications.

The robots could fill the gap between scanning probe microscopes, which can manipulate atoms one at a time but are too slow to make building complete devices practical, and other manufacturing methods that cannot operate at such a small scale.

The limbs, made from a shape memory alloy, have been developed by Ken Clements, chief executive of California-based Innovation on Demand, using US government grants. The application of energy, either using lasers or ultrasound, causes the material to change shape, allowing the legs to move or the arms to grip. Loss of the energy causes the material to revert to its original shape. A direct beam of energy is required because no battery or other power source is yet small enough for the robots.

New York state-based technology developer Technology Innovations is working with Innovation on Demand, and aims to link up with other companies, universities and government agencies to build a nano robot using the arms and legs, said Michael Riedlinger, the firm’s vice president for new business development.

The tiny limbs are made in a similar process to that used to make semiconductors, he said. ‘First of all we use the sputtering process to place titanium and nickel particles on to a silicon wafer. Then we use photolithography, the same process that produces microchips, to produce the arms and legs. Finally we have a way of lifting the formed limbs off the wafer’s surface.’

The firm is talking to companies and universities that specialise in nanotechnology, and has had interest from NASA and DARPA.