Design, Analysis and Fabrication of a Vaporizing Liquid Micro-Thruster

The design and fabrication of a newly proposed vaporizing liquid micro-thruster concept i s described. The intended purpose of this thruster concept is for use as an attitude control device o n new generat ions of very small spacecraft envisioned by the Nat ional Aeronaut ics and Space Administration (NASA), ranging in mass between 1 20 kg. The vaporizing liquid micro-thruster concept heavily relies on microfabrication techniques to achieve order of magnitude reductions i n both s ize and weight to f i t the des ign l imits of the envis ioned microspacecraft e n v i r o n m e n t . Attention was focused on thermal design aspects to limit power requirements to values less than 5 W, requiring specially contoured substrate shapes and packaging of the thruster chip. Since the thruster concept consists of a bonded structure and will be pressurized internally, bond strength tests were performed. Anodic bonds were found to be more than sufficient to maintain the current design internal pressures of 340 kPa. Several chips were fabricated and are currently awaiting performance testing.