Abstract. Many inspection tasks of structures are already carried out by unmanned aerial vehicles (UAV). Most of these inspections consist of using payloads for close range remote sensing purposes (i.e. digital cameras, thermal or LiDAR sensors). In all these inspection tasks the UAV system does not need to be close to the structure and typically the GPS coverage is good to perform mission navigation. In this paper, a smart payload developed for navigation in the neighbourhood of structures is presented. With this payload the UAV system is able to control the distance to a structure and the angle formed by the UAV and the structure in the horizontal plane. This payload has been calibrated in order to determine the calibration curve and measure the accuracy of the payload. The system has been tested in an indoor environment (GPS-denied). Good position and angular results has been obtained.