• 한국항공우주학회지
• /
• 제49권9호
• /
• pp.749-757
• /
• 2021

쿼드로터를 활용한 운송 임무에서 임의의 유상하중을 장착하게 되면 질량, 관성모멘트, 무게중심의 위치와 같은 모델 파라미터가 변화하게 된다. 더욱이 유상하중이 기체에 장착되는 위치가 기체의 무게중심과 일치하지 않는 경우 무게중심의 변화는 야기되며 이는 제어 성능에 악영향을 미치게 된다. 이에 본 논문에서는 유상하중에 따른 모델의 불확실성을 보상하기 위하여, 선형 제차 조정기(Linear Quadratic Regulator, LQR) 기반의 모델 참조 적응 제어기법(Model Reference Adaptive Control, MRAC)을 제안한다. 먼저 고정된 유상하중을 고려한 쿼드로터의 동역학 모델을 유도하고, 선형 제차 조정기를 이용하여 기준제어기를 선정한다. 참조 모델은 과도응답을 향상하기 위해 폐루프 참조 모델을 사용하였으며, 선형 제차 조정기를 통하여 선정하였다. 또한, 안정성 분석을 통하여 모델 파라미터를 추정하기 위한 적응 제어기법을 설계하였다. 제안하는 제어기의 성능을 확인하기 위하여 모델 파라미터의 불확실성이 존재하는 상황에서 선형 재차 조정기와 성능을 비교하였다. 그리고 외란이 있는 상황에서 기존의 모델 참조 적응 제어기법과도 제안한 제어기의 결과를 비교하여 과도응답과 강건성에 대해서도 분석하였다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2011년도 제42회 하계학술대회
• /
• pp.1922-1923
• /
• 2011

본 눈문은 쿼드로터 무인항공기의 모델링 및 제어기 설계에 대해서 논의한다. 라그랑지안 방정식을 이용하여 쿼드로터 무인항공기 시스템을 모델링하며, 실험을 통해 모델 파라미터를 결정한다. 쿼드로터 모델과 구해진 파라미터 값을 PID 제어 기법과 동적표면제어기법을 이용하여 쿼드로터 무인항공기의 제어기를 설계한다. 마지막으로, 모의실험을 통해 PID 제어기와 본 논문에서 제안한 동적표면 제어기의 성능을 비교하고, 제안한 제어기의 우수성을 입증한다.

• International Journal of Aeronautical and Space Sciences
• /
• 제10권2호
• /
• pp.148-160
• /
• 2009

By the development of recent technology, a new variant of rotorcrafts having four rotors start drawing attention from aerial-robotics engineers more than before. Its potential spans from just being control device test bed to performing difficult task such as carrying surveillance device to unreachable places. In this regards, modeling a quad-rotor is significant in analyzing its dynamic behavior and in synthesizing control system for such a vehicle. This paper summarizes the modeling of a mini quad-rotor aerial vehicle. A first principle approach is considered for deriving the model based on Euler-Newton equations of motion. The result of the modeling is a simulation platform that is expected to acceptably predict the dynamic behavior of the quad-rotor in various flight conditions. Linear models associated with different flight condition can be extracted for the purpose of control synthesis.

• International Journal of Internet, Broadcasting and Communication
• /
• 제8권1호
• /
• pp.1-6
• /
• 2016

Keeping a system in stable state is one of the important issues of control theory. The main goal of our basic research is stability of unmanned aerial vehicle (quadrotor). This type of system uses a variety of sensors to stabilize. In control theory and automatic control system to stabilize any system it is need to apply feedback control based on information from sensors. Our aim is to provide balance based on the 3D spatial information in real time. We used PID control method for stabilization of a seesaw balancing system and the article presents our experimental results. This paper presents the possibility of balancing of seesaw system based on feedback information from stereo vision system only.

• 제어로봇시스템학회논문지
• /
• 제20권4호
• /
• pp.381-388
• /
• 2014

In this paper, the attitude of a quadrotor system is controlled by a time-delayed control method which uses the previous information to cancel out uncertainties in the system. Although the linear controller works for the attitude control, the robust performance against disturbance is relatively poor. Therefore, a time-delayed controller as a robust controller is used. Experimental studies are conducted to validate the performance by the time-delayed control method. The performances of both a linear controller and a time-delayed controller are compared.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2015년도 제46회 하계학술대회
• /
• pp.1329-1330
• /
• 2015

본 논문은 무인항공기의 한 종류인 쿼드로터의 고장허용 제어기를 제안한다. 라그랑지안 방정식을 이용하여 쿼드로터를 모델링하고 인접한 두 로터가 작동하지 않는 경우에 쿼드로터에 작용하는 힘을 고려한다. 두 로터가 작동하지 않는 경우에 몸체의 평형을 유지하기 위한 고장허용 제어기를 제안하고, 리아프노프 정리에 입각하여 제안한 제어기를 입력한 경우 쿼드로터가 점근적으로 안정하게 되는 것을 보인다. 두 로터가 작동하지 않는 쿼드로터에 제안한 제어기를 입력하여 모의실험을 시행하고, 이를 통해 제어기의 우수성을 입증한다.

• 전기학회논문지
• /
• 제66권7호
• /
• pp.1123-1130
• /
• 2017

This paper deals with the dynamic surface control based tracking control for a drone equipped with a 2-DOF manipulator. First, the dynamics of drone and 2-DOF manipulator are derived separately. And we obtain the combined model of a drone equipped with a manipulator considering the inertia and the reactive torque generated by a manipulator. Second, a dynamic surface control based attitude and altitude control method is presented. Also, multiple sliding mode control based position control method is presented. The system stability and convergence of tracking errors are proven using Lyapunov stability theory. Finally, the simulation results are given to verify the effectiveness of the proposed control method.

• International Journal of Aeronautical and Space Sciences
• /
• 제18권3호
• /
• pp.588-600
• /
• 2017

We develop a wireless, contact free power transfer mechanism that is safer than the direct metallic contact and robust to imperfect alignment on landing at the base station. A magnetic field is created using inductors on both the transmitting and receiving sides. We use the inductive wireless recharging to increase autonomy and decrease the sensor interference by reducing the inductor loop size. By locating four independent small receiver loops and corresponding four circuits around the quadrotor UAV, we can increase safety from circuit malfunctions in comparison to the use of just one loop. On the base station, four folding robotic bars are used to realign the receiver loops over the transmitter loops. After adequate recharging as measured by battery voltages or power consumption at the bae station, the UAV sends a signal to the base station to open the robotic bars and takes off once freed from the robotic bars.

• Journal of Information Processing Systems
• /
• 제19권5호
• /
• pp.563-575
• /
• 2023

Trajectory planning is a key technology for unmanned aerial vehicles (UAVs) to achieve complex flight missions. In this paper, a terminal constraints conversion-based Gauss pseudospectral trajectory planning optimization method is proposed. Firstly, the UAV trajectory planning mathematical model is established with considering the boundary conditions and dynamic constraints of UAV. Then, a terminal constraint handling strategy is presented to tackle terminal constraints by introducing new penalty parameters so as to improve the performance index. Combined with Gauss-Legendre collocation discretization, the improved Gauss pseudospectral method is given in detail. Finally, simulation tests are carried out on a four-quadrotor UAV model with different terminal constraints to verify the performance of the proposed method. Test studies indicate that the proposed method performances well in handling complex terminal constraints and the improvements are efficient to obtain better performance indexes when compared with the traditional Gauss pseudospectral method.

• 제어로봇시스템학회논문지
• /
• 제19권2호
• /
• pp.158-163
• /
• 2013

The fusion of the GPS (Global Positioning System) and DR (Dead Reckoning) is widely used for position and latitude estimation of vehicles such as a mobile robot, aerial vehicle and marine vehicle. Among the many types of aerial vehicles, grater focus is given on the quad-rotor and accuracy of the position information is becoming more important. In order to exactly estimate the position information, we propose the fusion method of GPS and Gyroscope sensor using the DEKF (Dual Extended Kalman Filter). The DEKF has an advantage of simultaneously estimating state value and a parameter of dynamical system. It can also be used even if state value is not available. In order to analyze the performance of DEKF, the computer simulation for estimating the position, the velocity and the angle in a circle trajectory of quad-rotor was done. As it can be seen from the simulation results using own proposed DEKF instead of EKF on own fusion method in the navigation of a quad-rotor gave better performance values.