Combined chemical and electric thruster solution for attitude control

In this paper, two different thruster types are combined into an eight thruster solution for attitude control of a spacecraft. Four electric thrusters and four chemical thrusters are all used to perform slew maneuvers where the chemical thrusters are turned off during fine attitude pointing. The simulations show that a combined thruster solution is more fuel optimal than a chemical thruster system. In addition, it comprises the accuracy of the electric thruster system and at the same time makes it possible to perform slew maneuvers with the speed of the chemical system. This enables a system that does not have to rely on momentum exchange devices for fine attitude pointing and eliminates the requirement for momentum dumping. It is shown that this is a viable solution that can be implemented on spacecrafts with high pointing accuracy requirements.