  This letter investigates the problem of controlling an aerial manipulator,
composed of an omnidirectional tilting drone equipped with a
five-degrees-of-freedom robotic arm. The robot has to interact with the
environment to inspect structures and perform non-destructive measurements. A
parallel force-impedance control technique is developed to establish contact
with the designed surface with a desired force profile. During the interaction,
a pushing phase is required to create a vacuum between the surface and the
echometer sensor mounted at the end-effector, to measure the thickness of the
interaction surface. Repetitive measures are performed to show the
repeatability of the algorithm.
