Apparatus and method for detection of contaminants within fluid-filled inertial sensors

A method for dynamically detecting contamination in a fluid-filled inertial sensor, the method comprising:

• generating an input oscillatory signal;
• actuating a float positioned within a fluid-filled housing of the inertial sensor according to the input oscillatory signal using a drive motor to impart an oscillatory motion to the float such that the fluid is agitated to encourage contaminants in the fluid of the inertial sensor to contact the float;
• acquiring data representative of the oscillatory motion of the float;
• analyzing a difference between the oscillatory motion of the float represented by the data and the input oscillatory signal;
• and
• identifying one or more of a presence or an amount of contaminants in the fluid based on the difference that is analyzed.

An apparatus for dynamic contamination detection in a pendulous integrating gyroscopic accelerometer (PIGA), the apparatus comprising:

• a float disposed within a housing of the PIGA that contains a fluid, the float configured to be displaced in response to acceleration of the PIGA for measurement of the acceleration;
• a drive motor operatively coupled to the float;
• and
• a controller configured to close a control loop around an input oscillation signal to the drive motor to cause the drive motor to oscillate the float within the fluid in the PIGA at a predetermined oscillatory motion, the drive motor configured to oscillate the float within the fluid to agitate the fluid and contact one or more contaminants within the fluid, the controller configured to compare actual oscillatory motion of the float with the predetermined oscillatory motion, the controller configured to identify a presence or amount of the one or more contaminants in the fluid based on a difference between the actual oscillatory motion of the float and the predetermined oscillatory motion.