Surgical instruments, instrument drive units, and surgical assemblies thereof

A surgical instrument is configured for coupling with an instrument drive unit that drives an actuation of the surgical instrument and operatively supports the surgical instrument. The surgical instrument includes a housing, an elongate body extending distally from the housing, an end effector extending distally from the elongate body, and a plurality of driven members rotatably disposed within the housing. The plurality of driven members is nested with one another. Each driven member of the plurality of driven members is coupled to a respective cable that is attached to the end effector. The plurality of driven members is configured for engagement with an instrument drive unit.