Arbitrary Change of the Relative Gain Array: Application to a Helicopter

https://doi.org/10.58571/CNCA.AMCA.2025.011

Resumen: In this work, the Relative Gain Array (RGA) is employed as a measure of input-output coupling in the operation of a two-degree-of-freedom (2DOF) helicopter platform. High levels of interaction between control channels typically affect the performance of multivariable control systems, especially when decentralized controllers are used. To address this, we propose a methodology that systematically modifies the RGA matrix to achieve a more favorable configuration, including decoupling, and improved closedloop performance. The approach involves analyzing the system’s steady-state gain matrix and applying a transformation that shifts the RGA values toward a desired target structure. Simulation results demonstrate that the proposed modification produces a significant change in system response, reducing or increasing coupling effects as required. These findings suggest a promising direction for the design of RGA-based controllers in practical multivariable systems, such as aerial platforms.

¿Cómo citar?

Orozco-Mora, J., Ruiz-León, J. & Ruiz-Beltrán, E. (2025). Arbitrary Change of the Relative Gain Array: Application to a Helicopter. Memorias del Congreso Nacional de Control Automático 2025, pp. 62-67. https://doi.org/10.58571/CNCA.AMCA.2025.011

Palabras clave

Relative Gain Array, Multivariable control, Coupling, input-output interaction.

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