Grid Wear Analysis of a Miniature Ion Engine

This paper focuses on the variation in extraction-ion beam performances in a miniature ion engine due to grid erosion. Because speed and cost are very important issues in microspacecraft development, we replace time-consuming grid wear tests with numerical simulations using the JAXA Ion Engine Development Initiatives (JIEDI) tool. By comparing the results obtained for a miniature ion engine with those of a 10 ion engine, we observe differences in the variation of extraction-ion beam performance for miniature and ordinarysized ion engines. The use of a gimballing device in a miniature-ion engine results in a significant mass penalty, and we present a numerical simulation for predicting erosioninduced variations in the thrust-vector direction in an ion engine.