Granulation :
Mechanical process in which the product is pressed through a sieve with a specially shaped rotor-arm to obtain a desired particle size.  This process results in a narrow distribution spectrum as only the product having the right shape, size & position is broken & passed through the sieve.
Oscillating rotor :
The oscillating motion of the rotor improves the granulating process.  This sensitive handling of the product emulates the hand operation of an experienced pharmacist.
One important feature of the oscillating granulator is the continuous variation of the speed & force applied to the material.  The back & forth motion of the rotor results in an even distribution of the material.