Flexible motor takes shape

Researchers from Pennsylvania State University have designed a motor that can be made in a range of shapes, including nearly flat.

Key to the flexibility of the design is lead zirconate titanate, a piezoelectric material that changes shape in the presence of an electric field.

The researchers bonded the material to a flexible metal strip to create a bendable arm. They translated the bending motion into the rotation of the motor by placing 12 arms around a shaft containing a ratchet mechanism and stimulating the arms in the same direction at once.

The researchers' prototypes reached speeds of 600 revolutions per minute.

The design's simplicity and low materials cost make the flat motor potentially cheaper than today's electric motors, according to the researchers. Components for the prototype are around $150; a commercial version might cost as little as $10 to mass produce, according to the researchers.

The researchers are currently working on using the motor in a refrigeration compressor. The flexible motor could also be used in small electronics devices and to change the shape of structural elements like fins or wings.