• Title, Summary, Keyword: unmanned surface vehicle

Search Result 142, Processing Time 0.048 seconds

Study on Unmanned Hybrid Unmanned Surface Vehicle and Unmanned Underwater Vehicle System

  • Jin, Han-Sol;Cho, Hyunjoon;Lee, Ji-Hyeong;Jiafeng, Huang;Kim, Myung-Jun;Oh, Ji-Youn;Choi, Hyeung-Sik
    • Journal of Ocean Engineering and Technology
    • /
    • v.34 no.6
    • /
    • pp.475-480
    • /
    • 2020
  • Underwater operating platforms face difficulties regarding power supply and communications. To overcome these difficulties, this study proposes a hybrid surface and underwater vehicle (HSUV) and presents the development of the platform, control algorithms, and results of field tests. The HSUV is capable of supplying reliable power to the unmanned underwater vehicle (UUV) and obtaining data in real time by using a tether cable between the UUV and the unmanned surface vehicle (USV). The HSUV uses global positioning system (GPS) and ultra-short base line sensors to determine the relative location of the UUV. Way point (WP) and dynamic positioning (DP) algorithms were developed to enable the HSUV to perform unmanned exploration. After reaching the target point using the WP algorithm, the DP algorithm enables USV to maintain position while withstanding environmental disturbances. To ensure the navigation performance at sea, performance tests of GPS, attitude/heading reference system, and side scan sonar were conducted. Based on these results, manual operation, WP, and DP tests were conducted at sea. WP and DP test results and side scan sonar images during the sea trials are presented.

Vision-Based Obstacle Collision Risk Estimation of an Unmanned Surface Vehicle (무인선의 비전기반 장애물 충돌 위험도 평가)

  • Woo, Joohyun;Kim, Nakwan
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.21 no.12
    • /
    • pp.1089-1099
    • /
    • 2015
  • This paper proposes vision-based collision risk estimation method for an unmanned surface vehicle. A robust image-processing algorithm is suggested to detect target obstacles from the vision sensor. Vision-based Target Motion Analysis (TMA) was performed to transform visual information to target motion information. In vision-based TMA, a camera model and optical flow are adopted. Collision risk was calculated by using a fuzzy estimator that uses target motion information and vision information as input variables. To validate the suggested collision risk estimation method, an unmanned surface vehicle experiment was performed.

Modified A* Algorithm for Obstacle Avoidance for Unmanned Surface Vehicle

  • Vo, Anh Hoa;Yoon, Hyeon Kyu;Ryu, Jaekwan;Jin, Taekseong
    • Journal of Ocean Engineering and Technology
    • /
    • v.33 no.6
    • /
    • pp.510-517
    • /
    • 2019
  • Efficient path planning is essential for unmanned surface vehicle (USV) navigation. The A* algorithm is an effective algorithm for identifying a safe path with optimal distance cost. In this study, a modified version of the A* algorithm is applied for planning the path of a USV in a static and dynamic obstacle environment. The current study adopts the A* approach while maintaining a safe distance between the USV and obstacles. Two important parameters-path length and computational time-are considered at various start times. The results demonstrate that the modified approach is effective for obstacle avoidance by a USV that is compliant with the International Regulations for Preventing Collision at Sea (COLREGs).

Dynamic Window Approach with path-following for Unmanned Surface Vehicle based on Reinforcement Learning (무인수상정 경로점 추종을 위한 강화학습 기반 Dynamic Window Approach)

  • Heo, Jinyeong;Ha, Jeesoo;Lee, Junsik;Ryu, Jaekwan;Kwon, Yongjin
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.24 no.1
    • /
    • pp.61-69
    • /
    • 2021
  • Recently, autonomous navigation technology is actively being developed due to the increasing demand of an unmanned surface vehicle(USV). Local planning is essential for the USV to safely reach its destination along paths. the dynamic window approach(DWA) algorithm is a well-known navigation scheme as a local path planning. However, the existing DWA algorithm does not consider path line tracking, and the fixed weight coefficient of the evaluation function, which is a core part, cannot provide flexible path planning for all situations. Therefore, in this paper, we propose a new DWA algorithm that can follow path lines in all situations. Fixed weight coefficients were trained using reinforcement learning(RL) which has been actively studied recently. We implemented the simulation and compared the existing DWA algorithm with the DWA algorithm proposed in this paper. As a result, we confirmed the effectiveness of the proposed algorithm.

A Numerical Analysis for the Dynamic Behavior of the Umbilical Cable of a Deep-sea Unmanned Underwater Vehicle (심해 무인잠수정 1차 케이블의 동적거동 수치해석)

  • Kwon, Do-Young;Park, Han-Il;Jung, Dong-Ho
    • Journal of Ocean Engineering and Technology
    • /
    • v.19 no.3
    • /
    • pp.31-38
    • /
    • 2005
  • Ocean developments gradually move to deep-sea in the 21 century. A deep-sea unmanned underwater vehicle is one of important tools for ocean resource survey. A marine cable plays an important role for the safe operation and signal transmission of a deep-sea unmanned underwater vehicle. The umbilical cable of a deep-sea unmanned underwater vehicle is excited by surface vessel motion and shows non-linear dynamic behaviors. A numerical method is necessary for analysing the dynamic behavior of a marine cable. In this study, a numerical program is established based on a finite difference method. The program is appled to 6000m long cable for a deep-sea unmanned underwater vehicle and shows good reasonable results.

Non-Liner Dynamic Analysis of First Cable of Deep-Sea Unmanned Underwater Vehicle (심해무인잠수정 1차 케이블의 비선형 동적 해석)

  • KWON DO-YOUNG;PARK HAN-IL;JUNG DONG-HO
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
    • /
    • /
    • pp.123-130
    • /
    • 2004
  • Ocean developments gradually move to deep-sea in the 21 century. A deep-sea unmanned underwater vehicle is one of important tools for ocean resource survey. A marine cable plays an important role for the safe operation of a deep-sea unmanned underwater vehicle. The first cable of a deep-sea unmanned underwater vehicle is excited by surface vessel motion and shows non-linear dynamic behaviors. A numerical method is necessary for analysing the dynamic behaviour of the first marine cable. In this study, a numerical program is estabilished based on a finite difference method. The program is appled to a 6000m long cable for a deep-sea unmanned underwater vehicle and shows good reasonable results.

  • PDF

Fused Navigation of Unmanned Surface Vehicle and Detection of GPS Abnormality (무인 수상정의 융합 항법 및 GPS 이상 검출)

  • Ko, Nak Yong;Jeong, Seokki
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.22 no.9
    • /
    • pp.723-732
    • /
    • 2016
  • This paper proposes an approach to fused navigation of an unmanned surface vehicle(USV) and to detection of the outlier or interference of global positioning system(GPS). The method fuses available sensor measurements through extended Kalman filter(EKF) to find the location and attitude of the USV. The method uses error covariance of EKF for detection of GPS outlier or interference. When outlier or interference of the GPS is detected, the method excludes GPS data from navigation process. The measurements to be fused for the navigation are GPS, acceleration, angular rate, magnetic field, linear velocity, range and bearing to acoustic beacons. The method is tested through simulated data and measurement data produced through ground navigation. The results show that the method detects GPS outlier or interference as well as the GPS recovery, which frees navigation from the problem of GPS abnormality.

A Study on Automatic Berthing Control of an Unmanned Surface Vehicle

  • Vu, Mai The;Choi, Hyeung-Sik;Oh, Ji-Youn;Jeong, Sang-Ki
    • Journal of Advanced Research in Ocean Engineering
    • /
    • v.2 no.4
    • /
    • pp.192-201
    • /
    • 2016
  • This study examined a PD controller and its application to automatic berthing control of an unmanned surface vehicle (USV). First, a nonlinear mathematical model was established for the maneuvering of the USV in the presence of environmental forces. A PD control algorithm was then applied to control the rudder and propeller during an automatic berthing process. The algorithm consisted of two parts, namely the forward velocity control and heading angle control. The control algorithm was designed based on longitudinal and yaw dynamic models of the USV. The desired heading angle was obtained using the "line of sight" method. Finally, computer simulations of automatic USV berthing were performed to verify the proposed controller subjected to the influence of disturbance forces. The results of the simulation revealed a good performance of the developed berthing control system.

Design, Development and Testing of the Modular Unmanned Surface Vehicle Platform for Marine Waste Detection

  • Vasilj, Josip;Stancic, Ivo;Grujic, Tamara;Music, Josip
    • Journal of Multimedia Information System
    • /
    • v.4 no.4
    • /
    • pp.195-204
    • /
    • 2017
  • Mobile robots are used for years as a valuable research and educational tool in form of available open-platform designs and Do-It-Yourself kits. Rapid development and costs reduction of Unmanned Air Vehicles (UAV) and ground based mobile robots in recent years allowed researchers to utilize them as an affordable research platform. Despite of recent developments in the area of ground and airborne robotics, only few examples of Unmanned Surface Vehicle (USV) platforms targeted for research purposes can be found. Aim of this paper is to present the development of open-design USV drone with integrated multi-level control hardware architecture. Proposed catamaran - type water surface drone enables direct control over wireless radio link, separate development of algorithms for optimal propulsion control, navigation and communication with the ground-based control station. Whole design is highly modular, where each component can be replaced or modified according to desired task, payload or environmental conditions. Developed USV is planned to be utilized as a part of the system for detection and identification of marine and lake waste. Cameras mounted to the USV would record sea or lake surfaces, and recorded video sequences and images would be processed by state-of-the-art computer vision and machine learning algorithms in order to identify and classify marine and lake waste.

VFH+ based Obstacle Avoidance using Monocular Vision of Unmanned Surface Vehicle (무인수상선의 단일 카메라를 이용한 VFH+ 기반 장애물 회피 기법)

  • Kim, Taejin;Choi, Jinwoo;Lee, Yeongjun;Choi, Hyun-Taek
    • Journal of Ocean Engineering and Technology
    • /
    • v.30 no.5
    • /
    • pp.426-430
    • /
    • 2016
  • Recently, many unmanned surface vehicles (USVs) have been developed and researched for various fields such as the military, environment, and robotics. In order to perform purpose specific tasks, common autonomous navigation technologies are needed. Obstacle avoidance is important for safe autonomous navigation. This paper describes a vector field histogram+ (VFH+) based obstacle avoidance method that uses the monocular vision of an unmanned surface vehicle. After creating a polar histogram using VFH+, an open space without the histogram is selected in the moving direction. Instead of distance sensor data, monocular vision data are used for make the polar histogram, which includes obstacle information. An object on the water is recognized as an obstacle because this method is for USV. The results of a simulation with sea images showed that we can verify a change in the moving direction according to the position of objects.