Robust Nonlinear Control System Synthesis Method for Electro-Mechanical Pointing Systems with Flexible Modes

This paper describes the design of a robust control system for a gun turret testbed called the ATB1000. The control system incorporates a control scheme based on sinusoidal-input describing function (SIDF) models of the testbed's drive subsystem to reduce the effects of backlash and nonlinear friction, and a dissipative control scheme to make the control system insensitive to the unmodeled dynamics and parameter imprecision associated with the flexible modes of the wheel/barrel subsystem.