Reconfigurable Asymmetric Embedded Magnetorquers for Attitude Control of Nanosatellites

Abstract

A miniaturized attitude control system (ACS), which is capable of attaining a high spin rate and good pointing accuracy, is an integral part of any small spacecraft. In this regard, embedded magnetorquers are gaining significant attention because they are inserted in printed circuit board (PCB) internal layers with no extra space occupation and result in almost no mass and development cost. In this article, an innovative embedded magnetorquer with asymmetric nonuniform geometric structure is presented. The proposed magnetorquer is optimized for various parameters of interest, i.e., magnetic moment, resultant generated torque, power consumed, and heat dissipation for a CubeSat standard nanosatellite by means of employing diverse nonunity track-width-ratio geometrical arrangements. The magnetorquer driver and reconfigurable circuit is implemented with commercial-off-the-shelf (COTS) components which are low cost and easily available from the market. Embedded coils with variable trace width were simulated in order to predict the accuracy and to achieve the maximum torque versus power dissipation ratio of the developed models. Time-varying rotational analyses are performed to evaluate the angular spin rates driven by the asymmetric coils. Due to embedded coil structure, a detailed thermal analysis is conducted for various coil configurations (i.e., series, parallel, hybrid, etc.) to preserve thermal limits and to ensure the efficacy of the system. The simulation results were validated through a comprehensive set of experimental measurements which also establishes the framework for selecting the optimal coils configuration based on specific mission requirements.