Abstract: The control framework based on the Explicit Reference Governor (ERG) demonstrates significant application potential in the aerospace field, with its core advantage lying in achieving safety control under multiple constraints with limited computational resources. However, its practical effectiveness depends on the accuracy and conservatism of dynamic safety margin calculations. Focusing on a two-degree-of-freedom (2-DOF) helicopter control platform with model uncertainties, this study proposes an enhanced ERG framework integrating a lowest-order Uncertainty and Disturbance Estimator (UDE) and a risk assessment module. The framework achieves performance breakthroughs through two key designs: 1) The introduction of the UDE to actively compensate for uncertainties, thereby improving the accuracy of trajectory prediction based on the nominal model and ensuring reliable dynamic safety margin calculation. 2) The embedding of a risk assessment module to avoid system response delays caused by overly conservative transitions of the Auxiliary Reference (AR). Multiple sets of simulation and physical comparative experiments verify that the enhanced framework retains inherent advantages while solving the problems of sensitivity to model accuracy and conservative auxiliary reference adjustments, simultaneously achieving reduced steady-state error and increased response speed.

Key words: 2-DOF helicopter, uncertainty and disturbance estimator, explicit reference governor, trajectory prediction, constraints control