symmetrical, made of nearly pure glass. This enables it to vibrate for long periods, similar to the ringing of a wine glass. (Image credit: Najafi Group)

A small, inexpensive, and highly accurate gyroscope, developed at the University of Michigan, navigates without GPS. The key to making the gyroscope is a nearly symmetrical mechanical resonator that looks like a Bundt pan crossed with a wine glass, made one centimeter wide.

A nearly perfect sheet of fused silica glass about a quarter of a millimeter thick is heated and molded into the Bundt-like shape. A metallic coating and electrodes are added the device is encased in a vacuum package.

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