Methods automatically and comprehensively self-test the operation, hardware, and programs of a robotic system to reveal problems in a robotic system. The system preferably evaluates repeatability of measurement by each distance sensor, an accuracy of measurement by each distance sensor, an accuracy of movement of any positioning joints used to position the robot arm, and an accuracy of at least one routine of the system control programs. The positioning joints may include one or more rotational joints or one or more translational joints. In some embodiments, the robotic system is a robotic pulse/echo layer thickness (PELT) system. When a robotic system has passed all of the tests, then the system performance has been verified. The inclusion of these self-tests allows a robotic PELT system owner to determine whether or not the robotic portion of a system is performing correctly.