This paper presents describing function analysis and control solution for a friction related problem encountered during the development of a voice coil actuated direct drive for use in turning of automotive camshafts. It is observed that the addition of a high accuracy tracking (repetitive) controller results in a system that is susceptible to limit cycle oscillations induced by Coulomb friction. A local acceleration feedback loop is utilized to shape the system response to disturbance forces and is shown to improve the drive stiffness and prevent performance deterioration due to friction.

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