Microfabrication and test of an integrated colloid thruster

This paper reports on the design, fabrication and test of an integrated colloid micropropulsion system for spacecraft attitude control using the ionic liquid EMI-BF4 as fuel. The principle of operation of the thruster is identical to electrospray ionization. The objective of the project was to demonstrate the feasibility and operability of arrays of microfabricated capillary emitters with individual extractor electrodes. This design approach results in an identical electric field distribution from one capillary to the other, avoids crosstalk and therefore allows for a more finely modulated thrust control. Spraying tests with different thruster configurations were conducted under vacuum conditions. Tests were performed with different thruster configurations and starting voltages around 700V were observed.