Abstract: Illustrative systems and methods for inserting an elongate flexible instrument into a target environment are described. An illustrative system includes a guide device positioned near an opening to the target environment and having a rotary mechanism and a motor configured to drive the rotary mechanism. The system further includes a sensor system associated with insertion of the elongate flexible instrument along an insertion axis and a processor communicatively coupled to the motor and the sensor system. The processor is configured to receive sensor data from the sensor system, evaluate the sensor data, and control, based on the evaluation, the motor to actuate the elongate flexible instrument along the insertion axis. In some examples, the processor controls the motor to vary a rate of rotation of the rotary mechanism based on a determined system status.