When you push or pull with a simple machine, you are applying a force and doing work. And, if you get more force out of a machine than you put into it, then that machine has a mechanical advantage.

Scientists have demonstrated that large groups of bacteria can turn microgears millions of times larger than themselves, showing potential for "smart" biomechanical systems. Interestingly, the ...

This article was updated Feb. 28, 2023. It was originally published March 1, 2000. Planetary gears can supply high levels of torque and high-speed reduction. They are also relatively compact compared ...