Systems and methods to monitor seats for diagnostics, prognostics and degradation
A method is provided for detecting a fault in a gear system for repositioning a seat assembly in an automotive vehicle. The gear system includes a gear train operatively coupled to a motor. The method includes the steps of measuring a current drawn by the motor to reposition the seat assembly, recording the current over time as a current waveform, converting the current waveform into a frequency domain, determining a base frequency of the current waveform based on the converted current waveform, calculating a power spectrum density at the base frequency, calculating a total band power of the power spectrum density, and determining whether the total band power is greater than a predetermined total band power threshold.
1. A method for detecting a fault in a gear system for repositioning a seat assembly in an automotive vehicle, wherein the gear system includes a gear train operatively coupled to a motor, the method comprising the steps of:
measuring a current drawn by the motor to reposition the seat assembly;
recording the current over time as a current waveform;
converting the current waveform into a frequency domain;
determining a base frequency of the current waveform based on the converted current waveform;
calculating a power spectrum density at the base frequency;
calculating a total band power of the power spectrum density; and
determining whether the total band power is greater than a predetermined total band power threshold.
2. The method as set forth in claim 1 , wherein if it is determined that the total band power is greater than the predetermined total band power threshold, recording an indication of a fault in memory.
3. The method as set forth in claim 1 , wherein if it is determined that the total band power is greater than the predetermined total band power threshold, providing a notification that a fault has been detected.
4. The method as set forth in claim 1 , further comprising the steps of:
monitoring a number of times that the total band power is greater than the predetermined total band power threshold; and
if the number exceeds a count threshold, providing a notification that a fault has been detected.
5. The method as set forth in claim 1 , further comprising the step of filtering noise from the current waveform prior to transforming the current waveform into the frequency domain.
6. A method for detecting a fault in a gear system for repositioning a seat assembly in an automotive vehicle, wherein the gear system includes a gear train operatively coupled to a motor, the method comprising the steps of:
measuring a current drawn by the motor to reposition the seat assembly;
recording the current over time as a current waveform;
using a continuous wavelet transformation process to calculate a signature of the current waveform; and
determining whether the signature is greater than a predetermined signature threshold.
7. The method as set forth in claim 6 , wherein if it is determined that the signature is greater than the predetermined signature threshold, recording an indication of a fault in memory.
8. The method as set forth in claim 6 , wherein if it is determined that the signature is greater than the predetermined signature threshold, providing a notification that a fault has been detected.
9. The method as set forth in claim 6 , further comprising the steps of:
monitoring a number of times that the signature is greater than the predetermined signature threshold; and
if the number exceeds a count threshold, providing a notification that a fault has been detected.
10. The method as set forth in claim 6 , further comprising the step of filtering noise from the current waveform prior to calculating the signature of the current waveform.
11. A method for detecting a fault in a gear system for repositioning a seat assembly in an automotive vehicle, wherein the gear system includes a gear train operatively coupled to a motor, the method comprising the steps of:
applying a voltage pulse to the motor;
measuring a current drawn by the motor while the voltage pulse is applied to the motor;
recording the current over time as a current waveform;
determining a rise time in the current waveform for the current to reach a predetermined current amplitude; and
determining whether the rise time is greater than a predetermined rise time threshold.
12. The method as set forth in claim 11 , wherein if it is determined that the rise time is greater than the predetermined rise time threshold, recording an indication of a fault in memory.
13. The method as set forth in claim 11 , wherein if it is determined that the rise time is greater than the predetermined rise time threshold, providing a notification that a fault has been detected.
14. The method as set forth in claim 11 , further comprising the steps of:
monitoring a number of times that the rise time is greater than the predetermined rise time threshold; and
if the number exceeds a count threshold, providing a notification that a fault has been detected.
15. The method as set forth in claim 11 , further comprising the step of filtering noise from the current waveform prior to calculating the rise time in the current waveform.
16. A method for detecting a fault in a gear system for repositioning a seat assembly in an automotive vehicle, wherein the gear system includes a gear train operatively coupled to a motor having a drive shaft, the method comprising the steps of:
measuring a hall effect signal from the drive shaft indicating a rotational position and a rotational speed of the drive shaft over time;
comparing the hall effect signal to an expected hall effect signal for the motor; and
determining whether the hall effect signal is different from the expected hall effect signal.
17. The method as set forth in claim 16 , wherein if it is determined that the hall effect signal is different from the expected hall effect signal, recording an indication of a fault in memory.
18. The method as set forth in claim 16 , wherein if it is determined that the hall effect signal is different from the expected hall effect signal, providing a notification that a fault has been detected.
19. The method as set forth in claim 16 , further comprising the steps of:
monitoring a number of times that the hall effect signal is different from the expected hall effect signal; and
if the number exceeds a count threshold, providing a notification that a fault has been detected.
20. The method as set forth in claim 16 , wherein the comparing step comprises determining whether a pulse period in the hall effect signal fluctuates over time.
21. The method as set forth in claim 16 , further comprising the step of terminating power to the motor, wherein the comparing step includes determining a number of pulses within the hall effect signal after terminating power to the motor.
22. The method as set forth in claim 16 , further comprising the step of determining whether the gear train has encountered an impact, wherein the comparing step includes determining a number of pulses within the hall effect signal after the gear train encountered the impact.