Nonlinear Dynamics and Control of a New Hydrazine Pump Generation

We are interested in small satellites. Up to now, it turns out that below a certain given pressure in the gas propulsion system reservoir, it is not possible to apply any impulse control even though the gas tank is far from to be empty. Therefore, the aim of this paper is to emphasize the studies carried out for the new generation of hydrazine pumps in small satellite propulsion systems, in terms of modeling, control and experiments in order to optimize the use of gas. It consists of an actuator conception for which it is possible to move the hydrazine pump leading to very short required displacements. It may be shown that the main advantages in using these new devices are: in the one hand the volume gain with respect to the existing satellites systems and in the other hand this will allow the system operates even if the gas reservoir pressure level is low, thus bringing great benefits.