The forthcoming of the fourth industrial revolution drives the implementation of autonomous systems and high collaborative robots inside the industrial environments. Flexibility and Adaptivity represent the keys to satisfy the increase of an always faster and low-cost market demands. The FIXIT project main objective is to provide an interactive support for the human operator in the industrial or logistic environment fitting the requirements of the industry 4.0. The scope of the thesis is to develop and implement a collision avoidance system for an Unmanned Aerial Vehicle (UAV) used for maintenance purposes implemented on the FIXIT. The platform of the UAV is composed by a flight controller, the Pixhawk 2.4.8, an onboard computer, the Jetson nano and the Intel realsense D435i depth camera.