Whisking mechanics and active sensing.

•Three-dimensional analysis reveals key features of whisking mechanics and geometry.•Head-centered, resting-whisker, and whisker-centered reference frames are described.•Localization behaviors (‘where’ is the object) involve temporal and kinematic cues.•Feature extraction (‘what’ is the object) is likely to exploit contact mechanics.•Rats’ whiskers may perform ‘haptic enclosure’ similar to a hand grasp.