DEVELOPMENT OF A LOW POWER, LOW MASS, SMALL AND EASILY DEPLOYABLE PLANETARY BROADBAND MICRO-SEISMOMETER

Imaging the interior structure and monitoring real-time changes in stresses of solar system objects, including comets, asteroids, and planets, is a critical next step in improving fundamental knowledge of their formation, evolution, and current state. These are key components of both the NRC Planetary Science 2013-2022 Decadal Survey and the NASA SMD 2007-2016 Science Plan. The most direct method for imaging and monitoring interior stresses is through analysis of seismological data. Fundamental new advances in how we image planetary bodies will come only with a major technological advance in a broadband seismometer flight instrument. At present, a robust, low power, low mass, small form factor, and relatively low cost broadband seismometer that can be employed across a broad range of mission types with various deployment scenarios does not yet exist. To achieve this first-order goal, a next generation seismic instrument must be developed. We propose to develop the Integrated Seismic Instrument System (ISIS), a complete broadband micro-seismometer instrument with comprehensive lab and field testing and validation that will be the basis of a flight instrument that can be proposed for a range of solar system missions. ISIS development builds upon our success in developing an innovative new miniaturized seismic sensing element under a current NASA Planetary Instrument Definition and Development Program (PIDDP) grant. We propose to integrate this sensing element with all other components to produce a full assembly of a micro-seismometer instrument prototype. While the sensing element itself is at TRL 4, the integrated instrument TRL is currently between 2 and 3. The other components of ISIS are straightforward to develop, based on our preliminary results, but require parallel efforts to complete a fully integrated instrument. These components include: ionic liquid electrolyte, sensor cell package, control electronics, and an instrument housing. With the integration and comprehensive testing, ISIS will be brought to TRL 4 and possibly close to 5 by the end of this three-year project. Development of ISIS will provide a fundamentally improved advancement in the technical state of seismic instrumentation available for flight opportunities. Its design steps far beyond any current flight instrumentation due to its unique and highly desirable combination of characteristics, including low mass, low power usage, high shock tolerance, lack of need to level, broadband sensor, and flexibility of deployment. The system will be available for a broad range of missions, enabling seismology to become a fundamental part of many mission sizes and types such as a lunar network mission or deployment on an asteroid or icy satellite to determine interior structure or current seismic activity. Further, the test of ISIS in multiple-node configuration will provide a concept validation for planetary miniaturized small aperture seismic array (SASA), which may benefit future seismic missions. The work will be performed collaboratively between Arizona State University (ASU) and the Johns Hopkins University Applied Physics Laboratory (APL), while engineering investigators at ASU and APL conduct fundamental instrument development, science investigators at ASU will lead the instrument verification and concept validation on SASA, and science investigators at APL will provide mission instrument related guidance for future exploration missions. More »