In a clinical laboratory, loading specimens into a centrifuge can be time consuming because different quantities have to be balanced in geometric loading.  Gary Howell, formerly with DuPont, has “built a better mousetrap” in this regard-a self balancing rotor.  Here is a description of his design and the reference has a You Tube video of the centrifuge in action:  “Rotor-Mate suspends and locates the rotor axially by means of two free-floating plastic ball bearing and race sets.  There are no springs or elastomers or sensors or cantilevers used in Rotor-Mate.  These bearings permit the rotor unfettered but limited radial excursion for center of geometry to center of mass rotor relocation.  The bearings are fee to move angularly [rotate] with the assembly not unlike typical Conrad bearing applications, BUT bearing race radial movement is restricted by predetermined internal dimensions.  During resonance, excessive rotor motion is damped by predicable friction between the plastic bearing balls and the bearing races and suspended metal parts.  Because resonance is induced at low rotor RPM [loose coupling], rotor energy is relatively low and minimal frictional damping is sufficient. Bearing stress is therefore low allowing considerable bearing longevity.”

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