• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.25 no.4
• /
• pp.170-176
• /
• 2017

In recent years, Unmanned Aerial Vehicles (UAVs) were actively developed in various fields. In development process of UAVs, flight test is performed to ensure that minimum safety requirements and technical requirements are met. By constructing flight test infrastructure such as takeoff and landing facilities, operation procedure, and equipments, flight test can be performed effectively. In this paper, operation procedures of civil UAV's flight test are proposed. The procedures proposed are composed by two main steps: first, planning and permitting procedure of flight test. Secondly, execution and control procedure of flight test.

• Journal of Mechanical Science and Technology
• /
• v.17 no.5
• /
• pp.654-667
• /
• 2003

This paper presents a consequence of the systematic approach to identify the aerodynamic parameters of an unmanned aerial vehicle (UAV) equipped with the automatic flight control system. A 3-2-1-1 excitation is applied for the longitudinal mode while a multi-step input is applied for lateral/directional excitation. Optimal time step for excitation is sought to provide the broad input bandwidth. A fully automated programmed flight test method provides high-quality flight data for system identification using the flight control computer with longitudinal and lateral/directional autopilots, which enable the separation of each motion during the flight test. The accuracy of the longitudinal system identification is improved by an additional use of the closed-loop flight test data. A constrained optimization scheme is applied to estimate the aerodynamic coefficients that best describe the time response of the vehicle. An appropriate weighting function is introduced to balance the flight modes. As a result, concurrent system models are obtained for a wide envelope of both longitudinal and lateral/directional flight maneuvers while maintaining the physical meanings of each parameter.

• Journal of Institute of Control, Robotics and Systems
• /
• v.14 no.12
• /
• pp.1244-1252
• /
• 2008

This paper presents the analysis results obtained by the flight test of reconfiguration flight control system for an aircraft. The reconfiguration flight control system was designed by using control allocation scheme that automatically distributes the demanded control moments determined by control law to each actual control surface. In this paper, some control allocation algorithms for reconfiguration control of general aircraft with redundant control surfaces are summarized and their performance evaluation results through nonlinear simulation and Hardware-In-the-Loop-Simulation (HILS) test are shown. Also, Unmanned Aerial Vehicle (UAV) system adopted as a platform for the flight test of reconfiguration flight controller and the implementation procedure of reconfiguration flight controller into real-time UAV system were introduced. Finally, flight test results were analyzed.

• Aerospace Engineering and Technology
• /
• v.8 no.1
• /
• pp.1-9
• /
• 2009

The ground integration test of Smart UAV has been performed according to the flight test plan. The flight test of full scaled model will be performed followed by 4 DOF ground rig test and a tethered hover test. Smart UAV is the first indigenous tiltrotor aircraft which can fly with fast cruise speed and take off or land vertically. In order to prove the flight control law of Smart UAV, the 40% scaled airplane was developed and have been tested. During flight test of small scaled model, many unique and unexpected problems occurred. After clearing these problems, fully automatic flight test was performed successfully. The experiences about many trouble shooting and resolving the problems would be basic material to avoid the unexpected but similar flight test problems hidden behind of the full scaled Smart UAV. This paper presents the detailed procedures of trouble shootings to solve the unique problems which occurred during the flight test of small scaled tiltrotor UAV.

• Journal of Institute of Control, Robotics and Systems
• /
• v.22 no.9
• /
• pp.759-765
• /
• 2016

This paper presents the principle, dynamics modeling and control, hardware implementation, and flight test result of a hybrid-type unmanned aerial vehicle (UAV). The proposed UAV was designed to provide both hovering and fixed-wing type aerodynamic flight modes. The UAV's flight mode transition was achieved through the attitude transformation in pitch axis, which avoids a complex rotor tilt mechanism from a structural and control viewpoint. To achieve this, a different navigation coordinate was introduced that avoids the gimbal lock in pitch singularity point. Attitude and guidance control algorithms were developed for the flight control system. For flight test purposes, a quadrotor attached with a tailless fixed-wing structure was manufactured. An onboard flight control computer was designed to realize the navigation and control algorithms and the UAV's performance was verified through the outdoor flight tests.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.18 no.4
• /
• pp.73-79
• /
• 2010

Flight test is the final and a mandatory process for the development of unmanned aerial vehicles(UAVs) as well as manned. Since most UAVs fly in a low speed and are prone to adverse weather conditions such as air turbulence, atmospheric weather environment around flight test regions will be a critical item to be considered for a flight test planning for UAVs. In this paper, we suggest a decision method for a UAV flight test schedule based on weather conditions of surface and upper atmospheres and also introduce a program for an effective flight test planning through weather forecasts.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.141.3-141
• /
• 2001

Since 1990´s, there has been many researches for the development of the Unmanned Aerial Vehicle (UAV). Especially, for the development of digital electronics, the technologies of UAV toward to the miniaturization low-cost, and high reliability. Therefore, recent trends for the development of UAV are focused on the development modern Flight Control System (FCS). In this paper, focusing on the FCS, the development process for Sejong Unmanned Research Vehicle -1 (SURV-1) from design to flight test is presented.

• 한국태양에너지학회:학술대회논문집
• /
• 2012.03a
• /
• pp.313-318
• /
• 2012

In the present study, the preliminary study on a small solar-powered RC airplane are performed for the development of a long-endurance solar-powered UAV. Solar energy enables the solar-powered UAV to fly longer or eternally. The solar-powered UAV transfers the solar energy to electric energy and this energy is used for the flight and the battery charge. To increase the flying time, the efficiency of the solar-cell power system must be increased and the required power for flight must be minimized. Hence, the system integration including solar cell and controller, the power system design, and the aerodynamic and structural designs of the UAV is very important. The present study have performed the design, manufacture, and flight test of the small solar-powered UAV for the preliminary study of the long-endurance solar-powered UAV. From this study, the system integration technology of the solar-powered UAV design is established, and the possibility and the issue points for the development of the long-endurance solar-powered UAV are discussed.

• Journal of Institute of Control, Robotics and Systems
• /
• v.18 no.9
• /
• pp.878-886
• /
• 2012

This paper investigates the implementation and flight test of realtime vision guided autopilot system based on virtual instrumentation platform. A graphical design process via virtual instrumentation platform is fully used for the image processing, communication between systems, vehicle dynamics control, and vision coupled guidance algorithms. A significatnt ojective of the algorithm is to achieve an environment robust autopilot despite wind and an irregular image acquisition condition. For a robust vision guided path tracking and hovering performance, the flight path guidance logic is combined in a multi conditional basis with the position estimation algorithm coupled with the vehicle attitude dynamics. An onboard flight test equipped with the developed realtime vision guided autopilot system is done using the rotary UAV system with full attitude control capability. Outdoor flight test demonstrated that the designed vision guided autopilot system succeeded in UAV's hovering on top of ground target within about several meters under geenral windy environment.

• Journal of Institute of Control, Robotics and Systems
• /
• v.14 no.5
• /
• pp.502-510
• /
• 2008

UAVs(Unmanned Aerial Vehicles) have many applications in military and commercial areas. The flight control system of UAVs is more important than manned aircraft's because the mission of UAVs must be operated without a human pilot. But very heavy and expensive navigation system makes it difficult to develop UAV flight control system. In this research, GPS/IMU integrated navigation filter was developed for light weight/low cost flight control system of small UAVs. With this navigation filter, full flight control system which has real time operating capability has been developed. The performance of the flight control system is basically checked by HILSIM (Hardware In the Loop SIMulation). Finally, the flight control system is verified by showing performance test result under real flight environment.