Mechanically reconfigurable reflector for future smart space antenna application

Abstract

Smart space antennas with mechanically reconfigurable reflectors (MRRs) not only compensate for shape errors induced by distortions in the reflector but, depending on the purpose, also change the service coverage area on the ground with the reshaped reflector. Although several simulation studies regarding different types of MRRs have been performed in the past few years, MRR designs are few because of the difficulty in developing a reflector with the proper mechanical properties and actuators with sufficient drive capacity. Managing the array of actuators is also an issue, particularly in space applications. This paper presents a prototype of a MRR system that consists of a flexible reflector, an actuator array, and a servo controller. The reflector is a layered structure of simple construction with capability of flexible tailoring of its mechanical properties for reshaping. Piezoelectric inchworm actuators were developed, each with large driving stroke and load capacity. Thirteen actuators attached to the back of the reflector provide specified linear displacements that adjust the surface shape of the reflector. To reduce the overall size of the MRR prototype system and the operating power, a distributed time-sharing control strategy was designed to control the actuator array. For a given target shape, the actuation values of the array were optimized. The optimization algorithm and reconfiguration of the MRR prototype were validated in experiments where two different target shapes with extreme deformations and curvatures are specified.

A Physics-Guided Coordinated Distributed MPC Method for Shape Control of an Antenna Reflector

“…Assume that the solution after p iterates is ( u 1 p ,…, u S p ) and the corresponding cost function value is Φ(u 1 p ,…, u S p ; z(tk)); let the optimal solution be (u 1 * ,…, u S * ) with a relevant cost function Φ(u 1 * ,…, u S * ; z(tk)). The input trajectory at convergence satisfies (39) A proof can be found in [32, p. 1024].…”

“…9. Before the end of this item, two other typical methods for active shape control of an antenna reflector, i.e., the least-square (LS) method [38] and particle swarm optimization (PSO) [39], are used for comparison. They can be coded directly by calling the corresponding solvers in the optimization toolbox of MATLAB software.…”

Principle, Design and Future of Inchworm Type Piezoelectric Actuators

“…When coupled with large output force/torque, the inchworm actuator is also widely used in medical engineering areas like drug delivery, cell manipulation, lab on a chip [23][24]. Compared with other piezoelectric actuators, the advantage of long stroke also employs inchworm actuator in precision position platform [25].…”

A Mechanically Rollable Reflectarray With Beam-Scanning Capabilities

“…Therefore, current research is focusing on developing compact/deployable beam-scanning HGAs for space applications [4]- [6]. The proposed solutions are generally based on traditional HGA technologies, such as, parabolic reflector antennas [7]- [9], phased array antennas [10]- [13], and reflectarray antennas (RAs) [14]- [18]. Compared to the parabolic reflector and phased array antennas, RAs provide highly directive and versatile beams while maintaining low mass, low fabrication cost, and low complexity [19], [20].…”