The Hand Drill method of friction fire making is about as raw as it gets. You spin a wooden drill against a wood board with your bare hands. This method has had one of the widest distributions on ...

To study fine touch, selecting samples based on how many mechanical instabilities they can form is more predictive than using the friction coefficient, which has been the default choice.

One type of friction can waste energy even when two perfectly smooth surfaces move against each other, but researchers are getting a handle on how to attenuate or stop it completely ...