Methods of solenoid valve control optimization

1. A method of optimizing control of a solenoid valve for operating a vitrectomy probe comprising:

coupling a valve with a pressurized gas source, a power supply for supplying a voltage to drive a current in a solenoid in the valve, and a vitrectomy probe with a first chamber and a second chamber on respective sides of a pneumatically driven diaphragm for reciprocating a probe cutter;

delivering, by the power supply, the voltage to supply the solenoid with the current which drives a solenoid plunger to alternatively deliver and vent pressurized gas through a first outlet line and a second outlet line which respectively deliver and vent the pressurized gas to and from the first chamber and to and from the second chamber of the vitrectomy probe;

monitoring, with a current sensor coupled to the solenoid, the current in the solenoid;

transmitting, by the current sensor to a system controller, a current signal;

receiving, by the system controller, the current signal from the current sensor;

identifying, by the system controller, when a plunger movement in the solenoid creates a back electromotive force (back EMF) that changes the current in the solenoid in a predetermined degree, wherein identifying when the plunger movement in the solenoid creates the back EMF further comprises the system controller:

observing that the current is higher in each of a series of samples at a sampling rate;

observing that a subsequent series of subsequent samples in a sampling band are successively lower and resulted in a total current drop greater than a predetermined threshold indicating a peak;

observing that another series of subsequent samples are successively higher indicating a rebound in the current after the current rebounded from a valley; and

identifying a movement of the solenoid plunger created back EMF by observing the peak and valley;

causing, by the system controller, the power supply to enter a pulse width modulation (PWM) mode of operation to cause a continued movement of the solenoid plunger and/or hold an end position of the solenoid plunger until power to the solenoid is turned off at a predetermined timing after detecting the back EMF;

collecting current data associated with the detected peaks and valleys of the current signal;

predicting, via a failure prediction model, a future valve failure, wherein the failure prediction model is trained based on quantified instances of valve failure determined from the collected current data; and

displaying, on a surgical console coupled to the vitrectomy probe, advice for service of the valve based on the predicted future valve failure.

2. The method of claim 1 , wherein the quantified instances of valve failure are detected through the current data falling in or out of a specified range.

3. The method of claim 1 , further comprising tracking performance of the valve based on the current data falling in or out of a specified range.

4. The method of claim 1 , further comprising tracking degradation of the valve based on the current data falling in or out of a specified range.

5. The method of claim 1 , further comprising training, via supervised learning, the failure prediction model for predicting future valve failures based on real-time current data of a future valve operation.

6. The method of claim 1 , further comprising based on the collected current data, adjusting valve duty cycle of the valve to compensate for variations in timing of valve open or close so that a desired pressure output can be reached for actuating the vitrectomy probe.

7. The method of claim 1 , wherein displaying advice for service of the valve based on the predicted future valve failure occurs prior to a subsequent vitrectomy procedure using the surgical console.

8. The method of claim 1 , wherein the predetermined threshold is 10 milliamps.

9. The method of claim 1 , wherein the PWM mode comprises a constant PWM with a fixed duty cycle and a fixed frequency.

10. The method of claim 1 , wherein the PWM mode comprises a variable PWM with a variable duty cycle and a variable frequency.

11. The method of claim 1 , wherein the collected current data comprises timing data describing a timing associated with the detected peaks and valleys of the current signal.