Abstract: A method of imaging an earth formation comprises identifying engagement data from an engagement sensor. The engagement data corresponds to an engagement of the instrumented engagement element with a borehole in the earth formation. The method includes identifying rotation data from a rotation sensor. The rotation data corresponds to a rotational orientation of the engagement data with respect to the borehole. The method includes mapping the engagement data to the rotation data to generate oriented engagement data.

Abstract: An epicyclic gear mechanism having a series of gear trains each including a rotatable cage, a plurality of planet gears, a stationary gear pinion and an output gear, all of the gear trains being mounted about a fixed shaft. The output gear of one gear train is operably associated with the input gear of a succeeding gear train and is rotatable relative to its cage, and a final output mechanism is associated with the last gear train of the series.