Vibration-attitude integrated control of a large two-dimensional planar phased array antenna

Abstract

Phased array antennas are pivotal for observing, identifying, and tracking targets, serving both military and civilian needs. They are growing larger and more complex to meet the demand for high-resolution Earth observation. However, their intricate design, low-frequency density, and significant coupling make dynamic analysis and control design challenging. This paper introduces a novel large-scale, space-deployable, two-dimensional planar phased array antenna and investigates its dynamic modeling and active control. Unlike traditional one-dimensional phased array antenna, this antenna can scan in two directions, providing a larger scanning area. To suppress antenna vibration, the paper proposes a control strategy using ropes as actuators. Firstly, the paper details the structure of the phased array antenna, including its attitude and vibration actuators. Then, using the hybrid coordinate method and the velocity variation principle, it derives the antenna's rigid-flexible coupled dynamic model. Subsequently, the paper designs an attitude-vibration controller for the antenna, integrating the computed torque control method, Linear Quadratic Regulator (LQR), and Bang-Bang control theory. This includes considering the unidirectionality and saturation of the rope control forces and optimizing the placement of rope actuators using Particle Swarm Optimization (PSO). Finally, numerical simulations validate the effectiveness and accuracy of the theoretical investigation. The results indicate that the antenna model possesses characteristics of low-frequency density and robust rigidity-flexibility coupling, with optimization of actuator quantity and placement enhancing control efficiency. Furthermore, the dynamic model accurately describes the antenna's behavior, achieving results consistent with ADAMS software. The attitude-vibration coupled controller maintains precise directional accuracy, effectively suppressing vibrations.