Fully Actuated Control for Directional Accuracy in Multiaxis Antennas utilizing Sliding Mode and STESO Observers

This study presents an innovative control strategy designed to substantially improve directional accuracy in multiaxis antenna systems. It achieves this by integrating sliding mode control (SMC) with fully actuated (FA) theory, further augmented by a super twisting extended state observer (STESO). Initially, a control-oriented dynamics model was developed, serving as a crucial foundation for the design and execution of the algorithm. This model, derived through an analytical methodology employing both general and quasi-coordinate Lagrangian formulations, accurately defines the kinematics and dynamics that are unique to multiaxis antennas. Subsequently, FA theory was applied to transform the dynamic model into a fully actuated configuration, streamlining the control of antenna movements and avoiding the complexities inherent to manipulating the original system. The subsequent integration of SMC with this transformed model, complemented by the deployment of a STESO, effectively mitigates uncertainties in the system model, thereby significantly enhancing control precision. Simulation experiments conducted using a multiaxis antenna system demonstrate the efficacy of the proposed method and show a substantial improvement in directional accuracy.