“Jet Spraying Drone” that can spray repair materials onto concrete structures has been developed. However, manual operation of drones that flies in at high altitudes makes it difficult to fly and keep a suitable position for spray works. In this study, we developed a “semi-autonomous flight system” that can keep position autonomously and have versatility. With this system, drones keep distance and angle to the target wall, and altitude autonomously, and can be operated manually only to the left and right direction. The experimental results on two different types of drones showed the flight accuracy and versatility of the system.
