Methods of operating a surgical instrument or a subsystem thereof
Systems and subsystems for using a robotic instrument are disclosed. The method includes engaging a first closure input puck with a first closure robotic output. The method includes rotating the first closure robotic output to cause the first closure input puck to rotate. The method includes rotating a cam gear via the rotation of the first closure input puck. Rotation of the cam gear causes a yoke pin to track through a cam track in the cam gear, and the yoke pin is coupled to a closure tube. Tracking of the yoke pin through the cam track causes the yoke pin to translate from a first position to a second position, thereby translating the closure tube.
1 . A method of operating a closure subsystem of a surgical instrument, the method comprising:
engaging a first closure input puck with a first closure robotic output;
rotating the first closure robotic output to cause the first closure input puck to rotate, and continuing to rotate the first closure robotic output until a predetermined threshold indicator is detected;
rotating a cam gear via the rotation of the first closure input puck; and
rotating, in response to the predetermined threshold indicator being detected, the first closure robotic output to a predetermined home position,
wherein rotation of the cam gear causes a yoke pin to track through a cam track in the cam gear, the yoke pin being directly or indirectly coupled to a closure tube,
wherein tracking of the yoke pin through the cam track causes the yoke pin to translate from a first position to a second position, thereby translating the closure tube,
wherein the predetermined threshold indicator is detected when the yoke pin is positioned within a constant force region of the cam track; and
wherein the yoke pin is positioned at an open position of the cam track when the first closure robotic output is in the predetermined home position.
2 . The method of claim 1 , wherein the predetermined threshold indicator comprises a threshold force.
3 . The method of claim 1 , wherein the predetermined threshold indicator comprises a threshold current.
4 . The method of claim 1 , wherein the predetermined threshold indicator comprises a threshold voltage.
5 . The method of claim 1 further comprising:
engaging a second closure input puck with a second closure robotic output;
rotating the second closure robotic output to cause the second closure input puck to rotate; and
rotating the cam gear via the rotation of the second closure input puck.
6 . The method of claim 5 further comprising:
rotating a first spur gear via rotation of the first closure input puck, the first spur gear rotating in a same direction as the first closure input puck; and
rotating a second spur gear via rotation of the second closure input puck, the second spur gear rotating in a same direction as the second closure input puck.
7 . The method of claim 6 , wherein:
the first spur gear is rotatably engaged with the cam gear; and
the second closure input puck is rotatably engaged with the cam gear.
8 . The method of claim 7 , wherein the second spur gear and the first spur gear are configured to rotate concurrently to share a mechanical load for distal translation of the yoke pin.
9 . The method of claim 7 , wherein the second spur gear rotates in an opposite direction of the first spur gear.
10 . The method of claim 1 , wherein movement of the yoke pin from the first position to the second position translates the closure tube distally onto an anvil ramp of an anvil.
11 . The method of claim 10 further comprising clamping tissue between the anvil and a cartridge of an end effector.
12 . The method of claim 1 , wherein the cam track comprises an open position, a high-speed compression region, a high force region, and a constant force region.
13 . The method of claim 12 , wherein the high-speed compression region, the high force region, and the constant force region each have different curvatures.
14 . The method of claim 13 , wherein the constant force region is shaped such that the yoke pin remains stationary when tracking through the constant force region as the cam gear rotates.
15 . The method of claim 1 , wherein the cam track comprises a first zone and a closure zone.
16 . The method of claim 15 , wherein rotation of the cam gear through the first zone provides faster distal movement of the yoke pin than rotation of the cam gear through the closure zone, and rotation of the cam gear through the closure zone provides a greater mechanical advantage to the yoke pin than rotation of the cam gear through the first zone.
17 . A method of operating a closure subsystem of a surgical instrument, the method comprising:
engaging a first closure input puck with a first closure robotic output;
rotating the first closure robotic output in a first direction to rotate the first closure input puck and, via the first closure input puck, a cam gear until a predetermined threshold indicator is detected; and
in response to detecting the predetermined threshold indicator, rotating the first closure robotic output in a second direction, opposite the first direction, to a predetermined home position;
wherein rotation of the cam gear causes a yoke pin directly or indirectly coupled to a closure tube to track along a cam track, thereby translating the closure tube;
wherein the predetermined threshold indicator is detected when the yoke pin is within a constant-force region of the cam track; and
wherein, when the first closure robotic output is in the predetermined home position, the yoke pin is at an open position of the cam track.
18 . The method of claim 17 , wherein the predetermined threshold indicator comprises at least one of a threshold force, a threshold current, or a threshold voltage.