Discrete-time control of LineDrone: An assisted tracking and landing UAV for live power line inspection and maintenance

This paper presents the design of a discrete-time control algorithm for power line tracking and assisted landing of Hydro-Quebec's LineDrone robot, a multirotor unmanned aerial vehicle (UAV) designed to land on and roll along live power lines. The algorithm automatically aligns the UAV with the cable while the pilot remains in control of the vertical and longitudinal positions, hence facilitating landing by having fewer degrees of freedom on which the pilot must focus. Emphasis is placed on the design of the discrete-time control law, which results in a closed-form algebraic solution of gains for given transient specifications. The proposed control system is also designed to meet the requirements of operation near live lines, which means that the system is immune to electromagnetic interference. The proposed control algorithm is experimentally validated on LineDrone hybrid UAV under real outdoor conditions.