초록 ▼

An accelerometer has an acceleration transducer producing uncorrected analog acceleration signals representing vertical, lateral, and longitudinal components of acceleration. An error correction system is connected to the acceleration transducer for receiving the uncorrected analog acceleration sign

An accelerometer has an acceleration transducer producing uncorrected analog acceleration signals representing vertical, lateral, and longitudinal components of acceleration. An error correction system is connected to the acceleration transducer for receiving the uncorrected analog acceleration signals. The error correction system includes a system controller for generating a plurality of correction coefficients, an analog to digital converter which converts the uncorrected analog acceleration signals to uncorrected digital acceleration signals, a filter for filtering the uncorrected digital acceleration signals, an error compensation circuit receiving the correction coefficients to compensate the uncorrected digital acceleration signals, and a digital to analog converter which converts the corrected digital acceleration signals to corrected analog acceleration signals. The error compensation circuit corrects for bias offset, cross-axis alignment errors, scaling errors, and thermal offset. The system controller arranges a plurality of calibration measurements into a matrix and inverts the matrix to calculate the correction coefficients.

대표청구항 ▼

What is claimed: 1. An accelerometer, comprising: vertical, lateral, and longitudinal acceleration transducers producing uncorrected analog acceleration signals and thermal signals, the uncorrected analog acceleration signals representing vertical, lateral, and longitudinal components of accelerati

What is claimed: 1. An accelerometer, comprising: vertical, lateral, and longitudinal acceleration transducers producing uncorrected analog acceleration signals and thermal signals, the uncorrected analog acceleration signals representing vertical, lateral, and longitudinal components of acceleration, and the thermal signals including a signal corresponding to a temperature of the vertical acceleration transducer, a signal corresponding to a temperature of the lateral acceleration transducer, and a signal corresponding to a temperature of the longitudinal acceleration transducer; an error correction system connected to the acceleration transducers for receiving the uncorrected analog acceleration signals and the thermal signals, the error correction system including, (a) a system controller for generating a plurality of correction coefficients based, at least in part, on sampling of each of the thermal signals, (b) an analog to digital converter which converts the uncorrected analog acceleration signals to uncorrected digital acceleration signals, and (c) an error compensation circuit receiving the correction coefficients to compensate the uncorrected digital acceleration signals and produce corrected digital acceleration signals. 2. The accelerometer of claim 1, wherein the error correction system further includes a digital to analog converter which converts the corrected digital acceleration signals to corrected analog acceleration signals. 3. The accelerometer of claim 1, wherein the correction coefficients generated by the system controller include coefficients that are based on a plurality of thermal calibration measurements that account for a thermal hysteresis effect at each of the vertical, lateral, and horizontal acceleration transducers. 4. The accelerometer of claim 1, wherein the system controller arranges a plurality of calibration measurements into a matrix, and wherein the system controller inverts the matrix to calculate the correction coefficients. 5. The accelerometer of claim 1, wherein each acceleration transducer is a micro-electro-mechanical systems transducer. 6. The accelerometer of claim 1, wherein the error correction system further includes a filter for filtering the uncorrected digital acceleration signals. 7. The accelerometer of claim 1, wherein the error compensation circuit corrects for errors selected from the group consisting of bias offset, cross-axis alignment errors, scaling errors, and thermal offset. 8. The accelerometer of claim 1, wherein the error compensation circuit corrects each of the vertical, lateral, and longitudinal components of acceleration in terms of the other components of acceleration. 9. An accelerometer-based system, comprising: a flight recorder; vertical, lateral, and longitudinal acceleration transducers connected to the flight recorder, the acceleration transducers producing uncorrected analog acceleration signals and thermal signals, the uncorrected analog acceleration signals representing vertical, lateral, and longitudinal components of acceleration and the thermal signals including a signal corresponding to a temperature of the vertical acceleration transducer, a signal corresponding to a temperature of the lateral acceleration transducer, and a signal corresponding to a temperature of the longitudinal acceleration transducer; and an error correction system connected to the acceleration transducer for receiving the uncorrected analog acceleration signals and the thermal signals, the error correction system including, (a) a system controller for generating a plurality of correction coefficients based, at least in part, on a sampling of each of the thermal signals, (b) an analog to digital converter which converts the uncorrected analog acceleration signals to uncorrected digital acceleration signals, and (c) an error compensation circuit receiving the correction coefficients to compensate the uncorrected digital acceleration signals and produce corrected digital acceleration signals. 10. The accelerometer-based system of claim 9, wherein the error correction system further includes a digital to analog converter which converts the corrected digital acceleration signals to corrected analog acceleration signals. 11. The accelerometer-based system of claim 9, wherein the system controller arranges a plurality of calibration measurements into a matrix. 12. The accelerometer-based system of claim 11, wherein the system controller inverts the matrix to calculate the correction coefficients. 13. The accelerometer-based system of claim 9, wherein each acceleration transducer is a micro-electro-mechanical systems transducer. 14. The accelerometer-based system of claim 9, wherein the error correction system further includes a filter for filtering the uncorrected digital acceleration signals. 15. The accelerometer-based system of claim 9, wherein the error compensation circuit corrects for errors selected from the group consisting of bias offset, cross-axis alignment errors, scaling errors, and thermal offset. 16. The accelerometer-based system of claim 9, wherein the error compensation circuit corrects each of the vertical, lateral, and longitudinal components of acceleration in terms of the other components of acceleration. 17. An accelerometer, comprising: vertical, lateral, and longitudinal acceleration transducer producing uncorrected acceleration signals and thermal signals, the thermal signals including a signal corresponding to a temperature of the vertical acceleration transducer, a signal corresponding to a temperature of the lateral acceleration transducer, and a signal corresponding to a temperature of the longitudinal acceleration transducer; and an error correction system connected to the acceleration transducer for receiving the uncorrected acceleration signals and the thermal signals, the error correction system including, (a) a system controller for generating a plurality of correction coefficients based, at least in part, on a sampling of each of the thermal signals, and (b) an error compensation circuit receiving the correction coefficients to compensate the uncorrected acceleration signals and produce corrected acceleration signals. 18. The accelerometer of claim 17, wherein the corrected acceleration signals are digital or analog signals. 19. The accelerometer of claim 17, wherein the uncorrected analog acceleration signals represent vertical, lateral, and longitudinal components of acceleration. 20. The accelerometer of claim 17, wherein the system controller arranges a plurality of calibration measurements into a matrix and inverts the matrix to calculate the plurality of correction coefficients. 21. The accelerometer of claim 17, wherein the error correction system further includes a filter for filtering the uncorrected digital acceleration signals. 22. A method of compensating for errors in an accelerometer, comprising: providing vertical, lateral, and longitudinal acceleration transducers producing uncorrected analog acceleration signals and thermal signals, the uncorrected analog acceleration signals representing vertical, lateral, and longitudinal components of acceleration, and the thermal signals including a signal corresponding to a temperature of the vertical acceleration transducer, a signal corresponding to a temperature of the lateral acceleration transducer, and a signal corresponding to a temperature of the longitudinal acceleration transducer; and generating a plurality of correction coefficients based, at least in part, on a sampling of each of the thermal signals, converting the uncorrected analog acceleration signals to uncorrected digital acceleration signals; and compensating the uncorrected digital acceleration signals with the correction coefficients to produce corrected digital acceleration signals. 23. The method of claim 22, further including converting the corrected digital acceleration signals to corrected analog acceleration signals. 24. The method of claim 22, further including measuring a plurality of calibration data; arranging the plurality of calibration data into a matrix; and inverting the matrix to produce the correction coefficients. 25. The method of claim 22, further including filtering the uncorrected digital acceleration signals. 26. The method of claim 22, wherein the step of compensating the uncorrected digital acceleration signals with the correction coefficients further includes correcting for errors selected from the group consisting of bias offset, cross-axis alignment errors, scaling errors, and thermal offset. 27. The method of claim 22, wherein the step of compensating the uncorrected digital acceleration signals with the correction coefficients further includes correcting each of the vertical, lateral, and longitudinal components of acceleration in terms of the other components of acceleration.