Solar Sail Attitude Control Using An Integrated Shape Memory Alloy Actuator
- Paper number
IAC-20,C2,9,10,x56906
- Author
Dr. Meilin Liu, China, Shanghai Jiao Tong University
- Coauthor
Dr. Xiaofeng Wu, Australia, The University of Sydney
- Year
2020
- Abstract
Solar sail has been widely discussed for deep space explorations and recently it has been used as a de-orbiting device for small satellites. This paper, however, presents an integrated shape memory alloy (SMA) actuator for solar sail attitude control. The flexible actuator has advantages in terms of power and weight. The bending mechanism and the dynamic model of the actuator are developed and simulated in Matlab. The proposed solar sail structure is a non-rigid body, and a neural network based adaptive control algorithm is developed and validated for the solar sail attitude control. The new solar sail concept employs eight SMA bending actuators for attitude control. This sail craft allows four quadrant sails to rotate or bend to change CM/CP offset with a maximum deformation angle of 30 degrees. This type of control mechanisms offers a large control torque without compromising the mass requirement. The simulation results show that the back propagation neural network based adaptive control algorithm is able to drive the nonlinear SMA actuator. The attitude controller is also proven to respond to the control inputs effectively and able to handle moderate external disturbances. This flexible solar sail actuator device is scalable and can be applied in solar sails with different sizes. Although there are limitations and practical uncertainties that need to be further investigated, the flexible SMA actuator is proven feasible for solar sail attitude control while the solar sail is used for orbit maneuver.
- Abstract document
- Manuscript document
(absent)