Pulsed plasma thrusters (PPT) are micro-propulsion devices used in satellites forstation keeping. Conventionally the plasma discharge in a PPT is initiated by a spark plug. Theprimary objective of the present work was to develop and characterize a PPT that does not need aspark plug to initiate the plasma discharge. If the spark plug is eliminated, the size of the thrusterscan be reduced and arrays of such thrusters can be manufactured using micro electro mechanicalsystems (MEMS) techniques, which can provide tremendous control authority over the satellitepositioning. A parallel rail thruster was built and its performances were characterized insidea vacuum chamber to elucidate the effect of vacuum level on the performance. The electricalperformance of the thruster was quantified by measuring the voltage output from a Rogowskicoil, and the thrust produced by the developed thruster was estimated by measuring the forceexerted by the plume on a light weight pendulum, whose deflection was measured using a laserdisplacement sensor. It was observed that the thruster can operate without a spark plug. Ingeneral, the performance parameters such as thrust, mass ablation, impulse bit, and specificimpulse per discharge, would increase with the increase in pressure up to an optimum level dueto the increase in discharge energy as well as the decrease in the total impedance of the plasmadischarge. The thrust efficiency is found to be affected by the discharge energy.
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