Using Inertial Measurement Units as Seismometers for Planetary Missions
Description:
Many upcoming landed NASA missions have Inertial Measurement Units (IMUs) for spacecraft navigation, presenting opportunities for seismic science. We explore using IMUs as strong motion accelerometers to capture active seismic source signals for investigating the lunar subsurface. Most NASA rovers use the Northrup Grumman LN-200S, a triaxial MEMS accelerometer that senses strong ground motion at 1-400 Hz with a minimum noise floor sensitivity of ~0.3 mm/s2/√Hz. IMU data collection is mostly limited to active seismic operations sampling at 100 Hz. Our goals are to 1) quantify IMU sensitivity to seismic signals from a rover and its subsystems; 2) characterize rover transfer function and seismic response; and 3) develop methods to assess subsurface structure from IMU data. Observed seismic signals are made of four convolved components: instrument response, source time function, rover transfer function, and ground response. Instrument, source, and rover response can be experimentally measured before flight to isolate lunar subsurface seismic velocity variations and properties. For instrument and source characterization, the Regolith and Ice Drill for Exploration of New Terrains (TRIDENT) served as an example seismic energy source. IMUs attached to drill supports of TRIDENT’s engineering model recorded drilling in rotary (16.2 Hz) and percussive (2 Hz) modes in a vacuum chamber. Both modes showed characteristic source functions and frequency responses detectable above the IMU noise floor with signal-to-noise ratios between 30 and 200. Due to the high noise floor, lower frequency content, signal aliasing and limited data, IMU seismic data's primary value will likely be in relative amplitudes and signal shapes between locations. IMU data from Lava Beds National Monument on solid basalt and tuff fragments suggest even highly aliased signals can distinguish solid basalt from tuff. Rover response varies by design and remains unconstrained. We plan to characterize rover transfer functions using Panning and Kedar (2019) and develop tools for extracting ground response and properties from IMU data.
Session: Planetary and Gravitational Wave Seismology [Poster]
Type: Poster
Date: 4/15/2026
Presentation Time: 08:00 AM (local time)
Presenting Author: Kathryn R. Gansler
Student Presenter: Yes
Invited Presentation:
Poster Number: 133
Authors
Kathryn Gansler Presenting Author Corresponding Author ganslerk@umd.edu University of Maryland, College Park |
Nicholas Schmerr nschmerr@umd.edu University of Maryland, College Park |
Jingchuan Wang jcwang1@caltech.edu California Institute of Technology |
Kevin Lewis klewis@jhu.edu Johns Hopkins University |
Benjamin Fernando bfernan9@jh.edu Johns Hopkins University |
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Using Inertial Measurement Units as Seismometers for Planetary Missions
Category
Planetary and Gravitational Wave Seismology