In this study, we aim to develop a navigation and control system that enables drones to fly autonomously with high accuracy in indoor environments, including narrow aisles. First, we propose an EKF-based vision-aided inertial navigation system with altimeter (VINS-ALT), which combines monocular-SLAM results with data from the IMU and altimeter. In addition, a detection and correction system is designed to reduce altimeter errors caused by changes in ground surface characteristics, such as steps and slopes. Furthermore, a flight control system that achieves both trajectory tracking performance and robustness is developed. Finally, the effectiveness of the entire system is validated through autonomous flight control experiments in an indoor environment.

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