How Motion Control Works

Accelerometer? I Hardly Knew Her!

Check batteries before use.
Check batteries before use.
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Moses points his rod skyward, stirring the engines of Yahweh to life. Waters part. Former slaves get their exodus on. Gyros may well factor into the design of Moses' fabulous staff, but much like your smartphone, it might also boast an accelerometer.

An accelerometer is a device that can measure the rate of acceleration, caused by gravity or by movement. Moses waves his rod around in the air; Moses throws it like a baton and catches it on the flip side. If there were an accelerometer in there, it could clock the rod's movement and speed.

Several types of accelerometers live inside our gadgets. For instance, piezoelectric accelerometers (such as the one in an iPhone) depend on materials such as crystals, which generate electric charges when stress is applied -- a measurable occurrence known as the piezoelectric effect.

Other accelerometers work by calculating the electrical resistance of materials under mechanical stress or changes in resistance due to a magnetic field. More advanced accelerometers depend on nanoscale micro-electro-mechanical system (MEMS) technology.

Accelerometers in your smartphone or strapped to your gym shorts tell you how far you've run on the treadmill. Accelerometers inside your Wii remote sense the tilt, movement and speed of your frantic arm movements -- and when these inputs are relayed to the gaming console itself, your motions influence the action in the game.

So was Moses' rod equipped with accelerometer nanotechnology? One movement might cause the waters to part, while another causes them to collapse in a torrent of Biblical payback.