Using Air-Bearing Based Platform and Cold Gas Thruster Actuator for Satellite Attitude Dynamics Simulation

This article describes the details in design and development of a satellite attitude dynamics simulator that is used to validate control algorithms, improve novel control methods, verify the operation of available actuators or sensors and exhibit the fundamentals of attitude dynamics to students or experts. This dumbbell style simulator is based on a spherical air-bearing and is able to produce a frictionless and torque-free environment for simulating spacecraft operational environment. The facility includes a variety of subsystems such as: cold-gas propulsion subsystem, inertial measurement unit, power-supply unit, on-board processor and semi-automatic mass balancing mechanism. The overall design of this system was pretty complicated especially when considering the mission requirements, operating constraints and functional limitations imposed by the ground-based simulation, thus, a detailed design procedure has been deployed and also, this procedure has been performed accurately. An explanation about dynamic equations of motion of simulator with on-off thrusters, software-based simulation, applying reliable control algorithm and balancing methodology is the next part of this article. Finally, the results of the realistic maneuvers of this satellite simulator are presented and investigated in detail.