A surgical system for selective connection to a robotic arm includes an instrument drive unit and a surgical instrument detachably coupled to the instrument drive unit. The instrument drive unit includes first and second actuators and a first translatable member operatively coupled with the first actuator. The surgical instrument includes an adapter portion, an elongate member extending distally from the adapter portion, and an end effector mounted on a distal end of the elongate member. The adapter portion has a first rotatable member operatively associated with the first translatable member. The first rotatable member is rotatable in response to translation of the first translatable member. The end effector is operatively coupled with the first rotatable member, wherein rotation of the first rotatable member effects a first function of the end effector.
