Fluid pump with adaptive filter

1. A system, comprising:

at least one data processor; and

at least one memory storing instructions which, when executed by the at least one data processor, result in operations comprising:

measuring, by a pressure sensor, a fluid pressure of fluid in a fluid supply line of an infusion pump, the fluid pressure comprising a motor pressure and a patient pressure, the motor pressure caused at least in part by a current of a motor of the infusion pump, and the patient pressure caused at least in part by movement of the patient;

determining, by the at least one data processor, the patient pressure, the determining comprising removing, by a filter coupled to the pressure sensor and the at least one data processor, the motor pressure from the measured fluid pressure; and

adjusting, based at least in part on the determined patient pressure, a setting of the infusion pump.

2. The system of claim 1 , wherein the removing further comprises:

generating a predicted motor pressure based on the current of the motor;

generating an error signal based on a comparison between the predicted motor pressure and the measured fluid pressure; and

removing the motor pressure from the measured fluid pressure when an error value representative of the error signal is less than an error threshold.

3. The system of claim 2 , wherein the comparison between the predicted motor pressure and the measured fluid pressure is a difference between the predicted motor pressure and the measured fluid pressure.

4. The system of claim 2 , wherein the error value is one or more of a norm of the error signal and a least means square of the error signal.

5. The system of claim 2 , wherein generating the error signal further comprises applying a tap filter coefficient to the error value.

6. The system of claim 2 , wherein the removing further comprises: determining whether the error value is less than the error threshold.

7. The system of claim 6 , wherein the removing further comprises:

determining that the error value is greater than or equal to the error threshold value; and

adjusting one or more filter coefficients of the filter, the one or more filter coefficients applied to the current of the motor;

generating an updated predicted motor pressure based on the adjusted one or more filter coefficients and the current of the motor.

8. The system of claim 7 , wherein the removing further comprises:

generating an updated error signal based on a comparison between the updated predicted motor pressure and the measured fluid pressure; and

determining that an updated error value indicative of the updated error signal is less than the error threshold.

9. The system of claim 1 , wherein the current of the motor is stored in a shift register of the filter.

10. The system of claim 1 , wherein the filter is a variable digital adaptive filter.

11. The system of claim 1 , further comprising:

the filter; and

the pressure sensor; wherein the at least one data processor comprises a controller.

12. A method, comprising:

measuring, by a pressure sensor, a fluid pressure of fluid in a fluid supply line of an infusion pump, the fluid pressure comprising a motor pressure and a patient pressure, the motor pressure caused at least in part by a current of a motor of the infusion pump, and the patient pressure caused at least in part by movement of the patient;

determining, by at least one data processor coupled to the pressure sensor, the patient pressure, the determining comprising removing, by a filter coupled to the pressure sensor and the at least one data processor, the motor pressure from the measured fluid pressure; and

adjusting, by the at least one data processor based at least in part on the determined patient pressure, a setting of the infusion pump.

13. The method of claim 12 , wherein the removing further comprises:

generating a predicted motor pressure based on the current of the motor;

generating an error signal based on a comparison between the predicted motor pressure and the measured fluid pressure; and

removing the motor pressure from the measured fluid pressure when an error value representative of the error signal is less than an error threshold.

14. The method of claim 13 , wherein the comparison between the predicted motor pressure and the measured fluid pressure is a difference between the predicted motor pressure and the measured fluid pressure.

15. The method of claim 13 , wherein generating the error signal further comprises applying a tap filter coefficient to the error value.

16. The method of claim 13 , wherein the removing further comprises: determining whether the error value is less than the error threshold.

17. The method of claim 16 , wherein the removing further comprises:

determining that the error value is greater than or equal to the error threshold value; and

adjusting one or more filter coefficients of the filter, the one or more filter coefficients applied to the current of the motor;

generating an updated predicted motor pressure based on the adjusted one or more filter coefficients and the current of the motor.

18. The method of claim 17 , wherein the removing further comprises:

generating an updated error signal based on a comparison between the updated predicted motor pressure and the measured fluid pressure; and

determining that an updated error value indicative of the updated error signal is less than the error threshold.

19. The method of claim 12 , wherein the filter is a variable digital adaptive filter.

20. A non-transitory computer-readable storage medium including program code, which when executed by at least one data processor, cause operations comprising:

measuring, by a pressure sensor, a fluid pressure of fluid in a fluid supply line of an infusion pump, the fluid pressure comprising a motor pressure and a patient pressure, the motor pressure caused at least in part by a current of a motor of the infusion pump, and the patient pressure caused at least in part by movement of the patient;

determining, by at least one data processor coupled to the pressure sensor, the patient pressure, the determining comprising removing, by a filter coupled to the pressure sensor and the at least one data processor, the motor pressure from the measured fluid pressure; and

adjusting, by the at least one data processor based at least in part on the determined patient pressure, a setting of the infusion pump.