Assuring Radiation Tolerance of a Langmuir Probe Instrument for Low-Cost Interplanetary Missions

With recent advancements in small-satellite technology and the onset of industry-wide budget constraints, the field of planetary space exploration has begun directing efforts toward the production of low-cost missions that are capable of achieving big-budget science objectives. For any interplanetary mission, radiation tolerance assurance is necessary to maximize the survivability of an instrument and characterize its measurement performance throughout the mission flight profile. In this work, the process of ensuring radiation tolerance is demonstrated for a suite of Langmuir probe instruments that will fly on NASA's upcoming dual small-satellite mission to Mars, the Escape and Plasma Acceleration and Dynamics Explorers (ESCAPADE). A case study is presented in radiation environment modeling, component selection, single-event effect (SEE) considerations, total ionizing dose (TID) testing practices, data processing, and risk assessment to demonstrate instrument performance assurance techniques that could apply to other similar low-cost interplanetary missions. It is shown that the ESCAPADE Langmuir probe (ELP) instrument design satisfies accuracy requirements after radiation testing up to 25 krad(Si). In addition, the viability of commercial components for long-duration space missions is discussed, and the results are presented for a low-cost analog-to-digital converter (ADC).