• 제목/요약/키워드: precision landing

Search Result 67, Processing Time 0.03 seconds

Vision-based Obstacle State Estimation and Collision Prediction using LSM and CPA for UAV Autonomous Landing (무인항공기의 자동 착륙을 위한 LSM 및 CPA를 활용한 영상 기반 장애물 상태 추정 및 충돌 예측)

  • Seongbong Lee;Cheonman Park;Hyeji Kim;Dongjin Lee
    • Journal of Advanced Navigation Technology
    • /
    • v.25 no.6
    • /
    • pp.485-492
    • /
    • 2021
  • Vision-based autonomous precision landing technology for UAVs requires precise position estimation and landing guidance technology. Also, for safe landing, it must be designed to determine the safety of the landing point against ground obstacles and to guide the landing only when the safety is ensured. In this paper, we proposes vision-based navigation, and algorithms for determining the safety of landing point to perform autonomous precision landings. To perform vision-based navigation, CNN technology is used to detect landing pad and the detection information is used to derive an integrated navigation solution. In addition, design and apply Kalman filters to improve position estimation performance. In order to determine the safety of the landing point, we perform the obstacle detection and position estimation in the same manner, and estimate the speed of the obstacle using LSM. The collision or not with the obstacle is determined based on the CPA calculated by using the estimated state of the obstacle. Finally, we perform flight test to verify the proposed algorithm.

Feasibility Study on Domestic Development of a Precision-Landing System for Korean Military Based on GNSS (위성항법시스템 기반 한국형 군용 정밀착륙체계 국내개발 방향 및 기술타당성 분석)

  • Lee, Keehoon;Ahn, Jongsun;Lee, Young Jae
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.16 no.6
    • /
    • pp.762-770
    • /
    • 2013
  • Korean military is currently using and operating a precision approach and landing system, called RAPCON (ASR/PAR), which is imported from overseas. However, drawbacks of this system are operational and cost problems that come along, e.g. straightness of the radio waves, limited ability of narrow searching, lack of interoperability, and high cost of installation and maintenance. Moreover, as the civilian air traffic control uses a similar system compared to the military, the so called DME/VOR/ILS, disturbance between these two systems triggered the consideration of GNSS as alternative system. In this paper, we conduct a research on trends in the field of precise approach and landing systems based on GNSS, analyze weaknesses of GNSS(jamming, fault) and consider possible solutions. Furthermore, we propose the precise approach and landing system based on GNSS to be used by the Korean military as we found it to be also suitable for military purposes. Finally, we examine the benefits of a domestic development with different focuses(development/cost of mass production/operational advantages and potential for increased performance).

Design of a Robust Precision Aerial Delivery System Soft Landing Algorithm (외란에 강인한 정밀공중물자수송시스템 연착륙 알고리즘 설계)

  • Kim, Taewook
    • Journal of Aerospace System Engineering
    • /
    • v.16 no.4
    • /
    • pp.77-87
    • /
    • 2022
  • The Precision Aerial Delivery System is an instrument designed to improve the poor landing accuracy of aerial delivery system with conventional circular parachutes, and is equipped with an Airborne Guidance Unit to safely transport supplies to the desired destination. Currently, the landing accuracy of the PADS product is reported as CEP50 100m and also differs significantly, depending on the actual topography and weather environment. In this study, HILS was constructed based on the 6DOF nonlinear modeling of PADS to analyze the maneuver characteristics of Ram Air Parachute under wind environments. By using the new algorithm a precision soft landing algorithm including Energy Management and Final Approach is designed. HILS results show that it is possible to achieve a precise soft landing within CEP50 40m, and it can be exploited to develop an actual PADS drop test.

Analysis of Tension Mask Thermal Deformations under Localized Heating and Prediction of Electron Beam Landing Shifts (국부가열에 의한 Tension Mask 의 열변형 해석 및 전자빔의 오착 예측)

  • Shin, Woon-Seo;You, Se-Jonn;Jang, Bo-Woong
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.16 no.8
    • /
    • pp.138-148
    • /
    • 1999
  • Thermal deformations of tension mask under localized heating are analyzed using finite element method and electron beam landing shifts are predicted by the analysis results. In CRT, electron beam landing shifts due to thermal deformations of the tension mask make the color purity of screen worse. In order to get the final results of thermal deformations, firstly the tension processes of the mask and following welding processes between the tensional mask and rail must be analyzed sequentially. And then, nonlinear transient thermo-elastic finite element analysis is performed on every part inside CRT including tension mask, wherein thermal radiation is a main heat transfer mechanism. Because the tension mask has numerous slits, the effective thermal conductivity and effective and effective elastic modulus is calculated, and the tension mask is modeled as a shell without slits. From the displacement results of tension mask, electron beam landing shifts is calculated directly. Experiments are performed to confirm our analysis results. Temperature distributions and beam landing shifts of tension mask are measured and the results are in good agreement with those of analyses.

  • PDF

Pilot Gaze Tracking and ILS Landing Result Analysis using VR HMD based Flight Simulators (VR HMD 시뮬레이터를 활용한 조종사 시선 추적 및 착륙 절차 결과 분석)

  • Jeong, Gu Moon;Lee, Youngjae;Kwag, TaeHo;Lee, Jae-Woo
    • Journal of the Korean Society for Aviation and Aeronautics
    • /
    • v.30 no.1
    • /
    • pp.44-49
    • /
    • 2022
  • This study performed precision instrument landing procedures for pilots with a commercial pilot license using VR HMD flight simulators, and assuming that the center of the pilot's gaze is in the front, 3-D.O.F. head tracking data and 2-D eye tracking of VR HMD worn by pilots gaze tracking was performed through. After that, AOI (Area of Interesting) was set for the instrument panel and external field of view of the cockpit to analyze how the pilot's gaze was distributed before and after the decision altitude. At the same time, the landing results were analyzed using the Localizer and G/S data as the pilot's precision instrument landing flight data. As a result, the pilot was quantitatively evaluated by reflecting the gaze tracking and the resulting landing result using a VR HMD simulator.

Automatic Landing System of Container Spreader (컨테이너 스프레더의 자동 랜딩 시스템)

  • 박경택;박찬훈;박영근
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2003.06a
    • /
    • pp.1688-1692
    • /
    • 2003
  • The automatic Landing system is used for the automatic functions of automatic transfer crane in the automated container terminal. It confirms and adjusts the alignment and pose between spreader and container and accomplishes the automatic loading/unloading job of containers in yard. Specially, it is required in the automated container terminal and is well adapted under the coarse external environments. This system used the laser sensors to recognize the alignment between spreader and container. In this paper the algorithm of recognition of the alignment and pose is presented and the result of its simulation is shown.

  • PDF

A Study on the Longitudinal and Lateral Errors of Air Vehicle Heading for Auto-landing

  • Park, Ji Hee;Park, Hong Sick;Shin, Chul Su;Jo, Young-Wo;Shin, Dong-Ho
    • Journal of Positioning, Navigation, and Timing
    • /
    • v.2 no.2
    • /
    • pp.115-121
    • /
    • 2013
  • For the auto-landing operation of an air vehicle, the possibility of auto-landing operation should be first evaluated by testing the navigation performance through a flight test. In general, navigation performance is tested by analyzing north/east/down (NED) errors relative to reference equipment whose precision is about 8~10 times higher than that of a navigation system. However, to evaluate the auto-landing operation of an air vehicle, whether the air vehicle approaches a glide path aligned with the runway, within a specific error, needs to be examined rather than examining the north/east errors of the navigation system. Therefore, the longitudinal/lateral errors of air vehicle heading need to be analyzed. In this study, a method for analyzing the longitudinal/lateral errors of a navigation system was proposed as the navigation performance test method for evaluating the safety during the auto-landing of an air vehicle. Also, flight tests were performed six times, and the safety of auto-landing was examined by analyzing the performance using the proposed method.