Non-repeatable runout measurement and simulation of fluid lubricated spindles

The non-repeatable runout (NRRO) of small self-acting air bearing spindles is investigated using high precision capacitance probe transducers. Transient NRRO, spindle start-up time, and power consumption are determined at start-up for horizontal and vertical spindle orientation. The design of fluid spindles for magnetic recording disk drive applications is optimized by means of finite element-based numerical simulation. Advantages and disadvantages of fluid lubricated spindles are discussed.