A robotic system is described for determining whether a flexible instrument has buckled. The robotic system comprises a medical instrument comprising an elongate body, and further comprises a first sensor placed in a first portion of the elongate body, and a controller. A command is directed to the elongate body. The first sensor generates sensor data providing information regarding a first measured status of the portion of the elongate body. The controller receives sensor data generated from the first sensor, and compare the first measured status with a first expected status expected to be caused by the command； and responsive to the first measured status deviating from the first expected status one of more or less than a first associated threshold, determine that the elongate body has buckled.
