ESA GNC Conference Papers Repository
Design of the NEMO-AM Attitude and Orbit Control System
The Nanosatellite for Earth Monitoring and Observation Aerosol Monitor (NEMO-AM) is a high fidelity nanosatellite developed and being built in the Space Flight Laboratory (SFL) at the University of Toronto. NEMO-AM is funded by the Indian Space Research Organization with the primary objective of observing aerosol content over specific geographic regions. The satellite has a mass of less than 20kg and will also serve to demonstrate the efficacy of autonomous Earth observation on a nanosatellite platform. The autonomous nature of the mission necessitates that the Attitude and Orbit Control System (AOCS) make the correct attitude-related decisions and steer the satellite between different operational modes. To facilitate this, the AOCS must intelligently handle sensor/actuator telemetry, predict the satellite orbital/attitude state with the telemetry or during blackout periods, construct the attitude terrestrial pointing trajectory and command the actuators to regulate the trajectory in real time. This paper describes the AOCS design of NEMO-AM and in particular, explores how its execution compliments the autonomous objectives. In addition, the constraints encountered during the AOCS development are explained. The implementations which help overcome these constraints are described in detail. Lastly, simulation and test results are presented to demonstrate the expected performance, both in terms of meeting the science goals and the autonomous technology demonstration objectives. NEMO-AM is anticipated to be ready for launch in 2014.