Adjustment of the motor control program based on detection of individual device drive train properties
A surgical stapling system includes a motor, a gear reducer assembly, a drive train, and a motor controller. A method of controlling the motor includes applying a first signal to the motor, receiving drive train operational data, comparing the drive train data to baseline data, and applying a signal having a different shape than the first signal to the motor. A method of characterizing the motor includes transmitting a perturbation signal, receiving motor function parameters, determining stapler system characteristics, and adjusting a controller function. A method of controlling a stepper motor includes applying a signal to the stepper motor, receiving stepper motor operational data, comparing the data to baseline data, and adjusting the signal. Another method of controlling the motor includes receiving motor rotational data, receiving gear rotation data, calculating a mechanical transfer function, determining non-idealities of the stapling system, and modifying a control signal based on the non-idealities.
1. A method of controlling a motor in a powered surgical stapling system, wherein the powered surgical stapling system comprises an anvil, a portion to receive surgical staples, a tissue cutting blade, the motor, a motor power supply, a drive train, and a motor controller, the method comprising:
applying, by the motor controller to the motor, a first motor control signal;
receiving, by the motor controller, data associated with an operation of the drive train;
comparing, by the motor controller, the data associated with the operation of the drive train to baseline data associated with the operation of the drive train; and
applying, by the motor controller, a second motor control signal based on the comparison, wherein the second motor control signal differs from the first motor control signal in a shape of a pulse train of the first motor control signal,
wherein applying the second motor control signal based on the comparison comprises adjusting a PID control parameter, triggering a delay of a dynamic braking function, changing a level or a function window around a triggering threshold, adjusting a power applied to the motor from the motor power supply, or adjusting a pulse-width modulation signal applied to the motor.
2. The method of claim 1 , wherein receiving data associated with an operation of the drive train comprises receiving data associated with a frictional loss of the drive train, an acceleration response of the drive train, a deceleration response of the drive train, or mechanical harmonics of the drive train.
3. The method of claim 1 , wherein applying the first motor control signal comprises using a delta-sigma modulation based bit-stream controller to generate the motor control signal.
4. The method of claim 1 , wherein adjusting a pulse-width modulation signal applied to the motor comprises adjusting a shape of the pulse-width modulation signal rising portion, maximum amplitude portion, or falling portion.
5. A method of characterizing a motor in a powered surgical stapling system, wherein the powered surgical stapling system comprises an anvil, a portion to receive surgical staples, a tissue cutting blade, the motor, a motor power supply, a gear reducer assembly, and a motor controller, the method comprising:
transmitting, by the motor controller to the motor, a motor perturbation signal, wherein the motor perturbation signal comprises a chirp signal or a dithering signal;
receiving, by the motor controller, one or more motor function parameters;
determining, by the motor controller, one or more automated surgical stapler system characteristics based on the one or more motor function parameters; and,
adjusting, by the motor controller, one or more functions of the motor controller.
6. The method of claim 5 , wherein adjusting one or more functions of the motor controller comprises adjusting a motor drive current, a motor drive pulse-width modulation phase, a motor drive frequency, or a motor drive current.
7. The method of claim 5 , wherein receiving one or more motor function parameters comprises receiving a motor latency parameter, a motor frequency dependent torque parameter, or a motor current draw parameter.
8. The method of claim 5 , wherein determining one or more automated surgical stapler system characteristics comprises determining a system friction, a system inertia, a system backlash, or a system latency.
9. The method of claim 5 , wherein transmitting the motor perturbation signal comprises transmitting a step signal.
10. The method of claim 5 , further comprising transmitting, by the motor controller to the motor, a motor operational signal along with the motor perturbation signal.
11. A method of controlling a stepper motor in a powered surgical stapling system, wherein the powered surgical stapling system comprises an anvil, a portion to receive surgical staples, a tissue cutting blade, the stepper motor, a drive train mechanically coupled to the stepper motor, a stepper motor power supply, and a stepper motor controller, the method comprising:
applying, by the stepper motor controller to the stepper motor, a motor control signal;
receiving, by the stepper motor controller, data associated with an operation of the stepper motor coupled to the drive train;
comparing, by the stepper motor controller, the data associated with the operation of the stepper motor coupled to the drive train to baseline data associated with an operation of an uncoupled stepper motor, wherein the baseline data associated with an operation of an uncoupled stepper motor comprises one or more of a motor pull-in torque, a motor pull-out torque, or a motor holding torque of the uncoupled stepper motor; and
adjusting, by the motor controller, the motor control signal based on the comparison.
12. A method of controlling a motor in a powered surgical stapling system, wherein the powered surgical stapling system comprises an anvil, an anvil clamping trigger, the motor, a gear reducer assembly, a drive bar, and a motor controller, the method comprising:
receiving, by the motor controller, rotational data from a first rotational sensor affixed to a shaft of the motor;
receiving, by the motor controller, gear rotation data from a second rotational sensor affixed to an output shaft of the gear reducer assembly;
calculating, by the motor controller, a mechanical transfer function based at least in part on the rotational data and the gear rotation data;
determining, by the motor controller, mechanical system non-idealities of the powered surgical stapling system; and
modifying, by the motor controller, a motor control signal based on the determined mechanical system non-idealities.
13. The method of claim 12 , wherein modifying the motor control signal comprises modifying one or more of a motor control signal voltage, a motor control signal current, and a motor control pulse duty cycle.
14. The method of claim 12 , further comprising determining, by the motor controller, a motor response latency.
15. The method of claim 12 , further comprising determining, by the motor controller, one or more of a gear backlash, a gear slop, gear clearance, and a gear mechanical loss of the gear reducer assembly.
16. The method of claim 12 further comprising:
receiving, by the motor controller, linear motion data from a sensor of a linear position of the drive bar; and
calculating, by the controller, a second mechanical transfer function based at least in part on the rotational data, the gear rotation data, and the linear motion data.
17. The method of claim 12 further comprising:
receiving, by the controller, trigger motion data from a motion sensor in mechanical communication with the anvil clamping trigger;
receiving, by the controller, anvil position data from an anvil position sensor; and
determining, by the controller, a time delay between a motion of the anvil clamping trigger and a motion of the anvil.