Adding Nanomuscle To Micromotors

For every CPU manufactured, there are 10 micromotors sold, according to Rod MacGregor, president of NanoMuscle Inc., a nanotechnology company that hopes to exploit this trend. The Antioch, Calif., startup makes an actuator that's about the size of a small paper clip but is capable of pulling 140 grams of weight. These micromotors can be used in automotive controls such as instrumentation gauges, consumer electronics such as CD and DVD players, and in computer equipment such as PDAs, PC memory sticks, copiers, disk drives, printers, and scanners--essentially anywhere a small, noiseless motor is needed to move a component.

The NanoMuscle Actuator uses smart materials that let it be both a source of motion and position sensor. These inherent properties should help manufacturers reduce the number of components needed in a device and the size of computer and consumer electronics. The material made with nanotechnology is called shape memory alloy, a combination of nickel and titanium that's stretched across a set of supports. Electrical current is applied to the SMA wire, forcing it to snap back to its original shape, and thus creating a force strong enough to lift about one-third of a pound. The nanotech components in the actuator are about the size of large flakes of ground pepper.

The alloy was developed for the U.S. Navy in the 1950s by Raychem Corp., but never fully commercialized in motors because of its unpredictable nature. NanoMuscle has developed a technique that overcomes those limitations, MacGregor says. The first mass-produced actuators hit assembly lines in South Korea on March 28.

NanoMuscle's linear motion devices could unseat traditional small electric motors and solenoids. The small form factor and low power-consumption characteristics of these micromotors are capable of delivering more than 1 million repetitions.