Towards Real-Time Accelerometer Bias Calibration: FY21 Status Update For Strapdown Gravity Aided Inertial Navigation System (GAINS)
[Technical Report, Final Report]
Naval Information Warfare Center Pacific
Pagination or Media Count:
With the goal of eventually enabling strapdown gravity aided inertial navigation, a means to compensate for the bias drift of a frequency modulated FM accelerometer is discussed. Background information on current methods for mobile gravity gradient detection, FM accelerometers, and their relations are outlined. A simple overview of parts fabrication using a commercial process is given. Important issues and design choices are noted. With regards to enabling large-amplitude frequency control, see the references in that section and the associated technical report. Next, device modeling is given with means to simulate accelerometer response. This model was then used to demonstrate a means to observe and compensate for bias drift. The report then transitions to experimental efforts. Simplified schematics of the experimental setup and electronics are given. For greater detail on the electronics, see the associated technical report referenced in that section. Using this apparatus, data was collected and processed. Methods to compensate for both long-term and short-term drift were noted. Using these methods, the estimate bias instability is about 180 ng, which is fairly respectable for a first iteration of a silicon-based accelerometer.
- Test Facilities, Equipment and Methods
- Navigation and Guidance