MECHANISMS FOR COMPENSATING FOR DRIVETRAIN FAILURE IN POWERED SURGICAL INSTRUMENTS

1 . A surgical instrument couplable to an end effector, comprising:

at least one drive mechanism operable to effect at least one motion in the end effector;

one or more vibration sensors configured to record vibrations generated by the at least one drive mechanism, wherein the one or more vibration sensors are configured to generate an output signal based on the sensed vibrations;

a plurality of frequency filters each defining a center frequency and a frequency bandwidth, wherein the frequency filters are configured to generate a filtered signal based on the received output signal; and

a controller, comprising:

a memory storing at least one predetermined threshold value; and

a processor, wherein the memory includes program instructions which, when executed by the processor, cause the processor to:

develop a processed signal based on the filtered signal, wherein the processed signal comprises a voltage amplitude at each of the center frequencies;

calculate a total sum of the voltage amplitudes at the center frequencies;

compare the calculated total sum to the at least one predetermined threshold value; and

determine a status of the surgical instrument based on the comparison.

2 . The surgical instrument of claim 1 , wherein determining a status of the surgical instrument comprises detecting a malfunction of the surgical instrument, and wherein the malfunction is detected when the calculated total sum is greater than or equal to the at least one predetermined threshold value.

3 . The surgical instrument of claim 1 , wherein the at least one predetermined threshold value comprises a minimum value and a maximum value.

4 . The surgical instrument of claim 3 , wherein determining a status of the surgical instrument comprises selecting an acceptable status when the calculated total sum is less than or equal to the minimum value.

5 . The surgical instrument of claim 4 , wherein determining a status of the surgical instrument comprises selecting a marginal status when the calculated total sum is greater than the minimum value but less than the maximum value.

6 . The surgical instrument of claim 5 , wherein determining a status of the surgical instrument comprises selecting a critical status when the calculated total sum is greater than or equal to the maximum value.

7 . The surgical instrument of claim 1 , wherein developing a processed signal comprises employing a fast Fourier transform to develop the processed signal.

8 . The surgical instrument of claim 1 , wherein the calculated total sum includes all voltage amplitudes of the processed signal that fall within the frequency bandwidths of the frequency filters and exceed a predetermined baseline.

9 . The surgical instrument of claim 1 , wherein the one or more vibration sensors are microphones.

10 . A method for determining a status of a surgical instrument including at least one drive mechanism, wherein the method comprises:

sensing via one or more vibration sensors vibrations generated by the at least one drive mechanism during a firing sequence of the surgical instrument;

generating an output signal based on the sensed vibrations;

filtering the output signal using a plurality of frequency filters each defining a center frequency and a frequency bandwidth to generate a filtered signal of the sensed vibrations;

processing the filtered signal to generate a processed signal of the sensed vibrations, wherein the processed signal comprises a plurality of voltage amplitudes at each of the center frequencies;

calculate a total sum of the voltage amplitudes at the center frequencies;

compare the calculated total sum to the at least one predetermined threshold value; and

determine a status of the surgical instrument based on the comparison.

11 . The method of claim 10 , wherein determining a status of the surgical instrument comprises detecting a malfunction of the surgical instrument, and wherein the malfunction is detected when the calculated total sum is greater than or equal to the at least one predetermined threshold value.

12 . The method of claim 10 , wherein the at least one predetermined threshold value comprises a minimum value and a maximum value.

13 . The method of claim 12 , wherein determining a status of the surgical instrument comprises selecting an acceptable status when the calculated total sum is less than or equal to the minimum value.

14 . The method of claim 13 , wherein determining a status of the surgical instrument comprises selecting a marginal status when the calculated total sum is greater than the minimum value but less than the maximum value.

15 . The method of claim 14 , wherein determining a status of the surgical instrument comprises selecting a critical status when the calculated total sum is greater than or equal to the maximum value.

16 . The method of claim 10 , wherein developing a processed signal comprises employing a fast Fourier transform to develop the processed signal.

17 . The method of claim 10 , wherein the calculated total sum includes all voltage amplitudes of the processed signal that fall within the frequency bandwidths of the frequency filters and exceed a predetermined baseline.

18 . The method of claim 10 , wherein the one or more vibration sensors are microphones.

19 . A surgical instrument couplable to an end effector, comprising:

at least one drive mechanism operable to effect at least one motion in the end effector;

one or more vibration sensors configured to record vibrations generated by the at least one drive mechanism, wherein the one or more vibration sensors are configured to generate an output signal based on the sensed vibrations;

a plurality of frequency filters each defining a center frequency and a frequency bandwidth, wherein the frequency filters are configured to generate a filtered signal based on the received output signal; and

a controller, comprising:

a memory; and

a processor, wherein the memory includes program instructions which, when executed by the processor, cause the processor to:

develop a processed signal based on the filtered signal, wherein the processed signal comprises a voltage amplitude at each of the center frequencies;

compare each voltage amplitude to a corresponding voltage amplitude of a previously processed signal based on previously sensed vibrations of the at least one drive mechanism; and

determine a status of the surgical instrument based on the comparison.

20 . The surgical instrument of claim 19 , wherein determining a status of the surgical instrument comprises detecting a malfunction of the surgical instrument, and wherein the malfunction is detected when a voltage amplitude of the processed signal is greater than a corresponding voltage amplitude of the previously processed signal.