Magnetic dipole moment estimation and compensation for accurate attitude control in nano-satellite missions

摘要

Nano-satellites provide space access to a broader range of satellite developers and attract interests as a application of the space developments. These days several new nano-satellite missions is proposed with sophisticated objectives such as remote-sensing and observation of astronomical objects. In these advanced missions, the nano-satellites usually must meet strict attitude requirements for obtaining scientific data or images. For low earth orbit nano-satellite attitude control, the magnetic disturbance dominates over other environmental disturbances, as a result of the satellite' s small moment of inertia, and this effects should be cancelled for precise attitude control. This research focuses on how to cancel these effects in orbit. A unique method to estimate and compensate the residual magnetic moment, which interacts with magnetic field and causes magnetic disturbance, will be presented. A Extended Kalman Filter is used with data from gyro sensors and magnetic sensors to estimate the magnetic disturbance, which is compensated for using a feed-forward controller. For more practical considerations of the magnetic disturbance compensations, this method is also examined in PRISM (Pico-satellite for Remote-sensing and Innovative Space Missions) mission. And this method is adopted to nano-astrometory mission Nano-JASMINE as an example for application to nano-satellites. This research concludes that the use of magnetic disturbance estimation and compensation are useful for nano-satellites missions which require high accurate attitude control.