Methods and systems for calibration and compensation of accelerometers with bias instability

A method for compensating for bias instabilities in accelerometers comprising:

• removing temperature cycle hysteresis through temperature cycling;
• limiting durations of high acceleration load dwell times, wherein high acceleration is an acceleration of more than 1 g;
• and
• determining a corrected accelerometer output to compensate for bias accumulated during the high acceleration load dwell times.

A method of removing bias accumulation from an accelerometer measured output, the output being measured at a center point of time of a high acceleration load interval, high acceleration being a load of more than 1 g, said method comprising:

• estimating bias accumulation at the center point of time, tc, according to
• 12 1 2 ⁢ ( a ⁡ ( t 2 ) - a ⁡ ( t 1 ) ) ,
• where a(t1) is measured accelerometer output for a 1 g load at a time prior to a beginning of the high acceleration load interval, and a(t2) is measured accelerometer output for a 1 g load at a time after an end of the high acceleration load interval;
• and
• correcting accelerometer output according to
• 13 a c = a ⁡ ( t c ) - 1 2 ⁢ ( a ⁡ ( t 2 ) - a ⁡ ( t 1 ) ) ,
• where a(tc) is measured accelerometer output at the center point of time.

A system configured to determine compensation coefficients for an accelerometer, said system comprising:

• a computer comprising a processor and a memory;
• a rate table comprising a chamber;
• a rate table controller connected to said computer and configured to run acceleration load profiles on said rate table, the acceleration load profiles stored in said memory of said computer;
• a temperature controller connected to said computer and configured to run temperature profiles in said chamber, the temperature profiles stored in said memory of said computer;
• and
• a device configured to measure output of said accelerometer, said device, said computer configured to receive and store output data from said device, said computer configured to estimate bias accumulation from measured accelerometer outputs, determine corrected accelerometer outputs, and determine compensation coefficients using the corrected accelerometer outputs.

A computer for removing bias accumulation from accelerometer measured outputs, the outputs being measured at a center point of time of a high acceleration load interval, high acceleration being a load of more than 1 g, said computer configured to:

• estimate bias accumulation at the center point of time, tc, according to
• 17 1 2 ⁢ ( a ⁡ ( t 2 ) - a ⁡ ( t 1 ) ) ,
• where a(t1) is measured accelerometer output at a time prior to a beginning of the high acceleration load interval, and a(t2) is measured accelerometer output at a time after an end of the high acceleration load interval;
• and
• correct accelerometer output according to
• 18 a c = a ⁡ ( t c ) - 1 2 ⁢ ( a ⁡ ( t 2 ) - a ⁡ ( t 1 ) ) ,
• where a(tc) is measured accelerometer output at the center point of time.