Attitude Control of a Nanosatellite using Inverse Simulation

Modern nanosatellites are being utilised more widely for missions that require high pointing accuracy of their instrumentation. Therefore, attitude control methods that can ensure pointing requirements are always met are needed. This paper explores the feasibility, performance and practicality of applying existing Inverse Simulation (InvSim) techniques to the attitude control problem. A series of different attitude manoeuvres are used to show the versatility of InvSim. Specific scenarios of an inertial pointing and spin-axis pointing rigid body 3U nanosatellite, with four reaction wheel actuators, are investigated. Performance of the InvSim controller is compared to Proportional-Integral-Derivative (PID) control through consideration of the pointing error, peak actuator power and total actuator energy of the attitude manoeuvres. InvSim is successfully implemented as an attitude controller, with comparable performance to traditional PID control in most cases, and performing better in the presence of higher nonlinear dynamics. In addition, two specific use cases are explored to show the superior practicality and versatility of InvSim, and its possible use as a design tool/aid