An apparatus, comprising: (a) an end effector comprising a staple driver , wherein the staple driver is operable to distally advance and proximally retract along the end effector; (b) a shaft assembly including a driver actuator in communication with the staple driver, wherein the driver actuator is operable to distally advance and proximally retract along a longitudinal axis of the shaft assembly such that motion of the driver actuator provides distal advancement and proximal retraction of staple driver ; and (c) a drive assembly in communication with the driver actuator , wherein the drive assembly comprises: (i) a motor , (ii) a rotary drive member in communication with the motor , whereby the motor is operable to rotate the rotary drive member , (iii) a first link in communication with the rotary drive member , and (iv) a first toggle link in communication with the first link , wherein the first toggle link is also in communication with the driver actuator ; (v) a mechanical ground ; (vi) a second toggle link in communication with the first link , wherein the second toggle link is also in communication with the mechanical ground ; wherein rotation of the rotary drive member is configured to induce linear motion in the first link , wherein the first link is configured to pivot the second toggle link in relation to the mechanical ground and the first toggle link in relation to the driver actuator , thereby straightening the first and second toggle links to convey linear motion to the driver actuator that is non-parallel to the linear motion of the first link . (a) an end effector comprising a staple driver , wherein the staple driver is operable to distally advance and proximally retract along the end effector; (b) a shaft assembly including a driver actuator in communication with the staple driver, wherein the driver actuator is operable to distally advance and proximally retract along a longitudinal axis of the shaft assembly such that motion of the driver actuator provides distal advancement and proximal retraction of staple driver ; and (c) a drive assembly in communication with the driver actuator , wherein the drive assembly comprises: (i) a motor , (ii) a rotary drive member in communication with the motor , whereby the motor is operable to rotate the rotary drive member , (iii) a first link in communication with the rotary drive member , and (iv) a first toggle link in communication with the first link , wherein the first toggle link is also in communication with the driver actuator ; (v) a mechanical ground ; (vi) a second toggle link in communication with the first link , wherein the second toggle link is also in communication with the mechanical ground ; wherein rotation of the rotary drive member is configured to induce linear motion in the first link , wherein the first link is configured to pivot the second toggle link in relation to the mechanical ground and the first toggle link in relation to the driver actuator , thereby straightening the first and second toggle links to convey linear motion to the driver actuator that is non-parallel to the linear motion of the first link . (i) a motor , (ii) a rotary drive member in communication with the motor , whereby the motor is operable to rotate the rotary drive member , (iii) a first link in communication with the rotary drive member , and (iv) a first toggle link in communication with the first link , wherein the first toggle link is also in communication with the driver actuator ; (v) a mechanical ground ; (vi) a second toggle link in communication with the first link , wherein the second toggle link is also in communication with the mechanical ground ; <EOS>