A medical system may comprise a catheter having a main lumen and a distal tip positioned in a working configuration at a working location. The medical system may also comprise a sensor system coupled to the catheter to generate measurement signals. The medical system may also comprise a control system. The control system may be configured to receive the measurement signals from the sensor system. The control system may be operable to identify from the received measurement signals the working configuration of the distal tip of the catheter. The control system may be configured to control at least one degree of freedom of the distal tip of the catheter to maintain the working configuration of the distal tip of the catheter based on a selected stiffness mode and the received measurement signals. The selected stiffness mode determines the at least one degree of freedom of the distal tip.