Everything from the 120MHz Cortex-M3 MCU to the three-axis accelerometer and the Bluetooth radio was on a single board.

ENGADGET

The photovoltaic system consists of three single-axis tracking units mounted to the ground.

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Today motion sensing has progressed to being three-axes of acceleration, and three axis of rotation (technically called gyroscopes).

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The probe was built with four reaction wheels and needs three of them -- one for each axis -- to aim its telescope precisely at a distant star, deputy project manager Charlie Sobeck said.

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The number of licenses issued for export of five-axis machine tools to China dropped from nine in 2006 to only three in 2007.

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