Constrained State-Space Coupling Numerator Solution and Helicopter External Load Control Design Application

摘要

The traditional constrained coupling numerator analysis for determining an effective single-input/single-output transfer function for a coupled multi-input/multi-output system is a useful tool for control system design. This Note successfully extends the constrained coupling numerator analysis to a state-space solution which allows multi-input analysis with some controls and states constrained. As an example, an architecture study of helicopter/load dynamic control was performed using Bode and root-locus methods for a cable angle/rate feedback control systems. The coupling numerator analysis provided a single-axis model for evaluation of control system architectures for an unstable, highly coupled helicopter with an external load. This Note showed that development of a state-space solution for the constrained coupling numerator analysis is possible, as long as the resulting M matrix is invertible. This state-space coupling numerator analysis was successfully used for effective single-input/ multi-output design of a multi-input/multi-output control system. Use of the constrained state-space coupling numerator analysis on the UH-60 cable angle feedback design study led to the identification of the handling qualities/load damping tradeoff, which resulted in the development and successful flight test of a novel task-tailored cable angle feedback control system.