• Title, Summary, Keyword: obstacle avoidance

Search Result 545, Processing Time 0.036 seconds

A Study on the Obstacle Avoidance of a Multi-Link Robot System using Vision System (Vision System을 이용한 다관절 로봇팔의 장애물 우회에 관한 연구)

  • 송경수;이병룡
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • /
    • pp.691-694
    • /
    • 2000
  • In this paper, a motion control algorithm is proposed by using neural network system, which makes a robot arm successfully avoid unexpected obstacle when the robot is moving from the start to the goal position. During the motion, if there is an obstacle the vision system recognizes it. And in every time the optimization-algorithm quickly chooses a motion among the possible motions of robot. The proposed algorithm has a good avoidance characteristic in simulation.

  • PDF

Real time obstacle avoidance for autonomous mobile robot (이동 로봇의 실시간 충돌회피)

  • 권영도;이진수
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.434-439
    • /
    • 1993
  • This paper present a sensor based obstacle avoidance method which is based on a VFH(Vector Field Histogram) method. The basic idea of obstacle avoidance is to find a minimum obstacle direction and distance. From the minimum sonar index and the target direction high level system determine steering angle of mobile robot. The sonar sensor system consists of 12 ultra sonic sensor, and each sensor have its direction and safety value. This method has advantage on calculation speed and small memory. This method is implemented on indoor autonomous vehicle'ALiVE-2'.

  • PDF

Obstacle Avoidance Algorithm for Vehicle using Fuzzy Inferences

  • Kawaji, Shigeyasu;Matsunaga, Nobutomo
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • /
    • pp.1246-1249
    • /
    • 1993
  • In this paper, we propose an algorithm of obstacle avoidance using fuzzy inferences. After the basic idea of the path generation algorithm using piecewise polynomials is described, the obstacle avoidance problem using fuzzy inferences is considered. Main concept of the avoidance algorithm is to modify intermittent point data using fuzzy inferences and to generate the collision free path based on the modified data. Finally, simulation result demonstrate the effectiveness of the proposed algorithm.

  • PDF

An Obstacle Detection and Avoidance Method for Mobile Robot Using a Stereo Camera Combined with a Laser Slit

  • Kim, Chul-Ho;Lee, Tai-Gun;Park, Sung-Kee;Kim, Jai-Hie
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.871-875
    • /
    • 2003
  • To detect and avoid obstacles is one of the important tasks of mobile navigation. In a real environment, when a mobile robot encounters dynamic obstacles, it is required to simultaneously detect and avoid obstacles for its body safely. In previous vision system, mobile robot has used it as either a passive sensor or an active sensor. This paper proposes a new obstacle detection algorithm that uses a stereo camera as both a passive sensor and an active sensor. Our system estimates the distances from obstacles by both passive-correspondence and active-correspondence using laser slit. The system operates in three steps. First, a far-off obstacle is detected by the disparity from stereo correspondence. Next, a close obstacle is acquired from laser slit beam projected in the same stereo image. Finally, we implement obstacle avoidance algorithm, adopting the modified Dynamic Window Approach (DWA), by using the acquired the obstacle's distance.

  • PDF

Obstacle Avoidance of Leader-Follower Formation (리더-추종자 대형제어의 장애물 회피)

  • Oh, Young-Suk;Park, Jong-Hun;Kim, Jin-Hwan;Huh, Uk-Youl
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.60 no.9
    • /
    • pp.1761-1766
    • /
    • 2011
  • This paper presents obstacle avoidance of Leader-Follower formation. The follower robot maintain the formation with leader robot and avoid the detected obstacle. When obstacle is detected, follower robot avoid it considering leader robot and follower robot position and follower robot and obstacle position. In addition, follower robot avoid obstacle irrespective of obstacle size. Controller of follower robot is designed to satisfy Lyapunov stability by backstepping method. Simulation results shows that the designed controller has a stable performance.

3D Depth Camera-based Obstacle Detection in the Active Safety System of an Electric Wheelchair (전동휠체어 주행안전을 위한 3차원 깊이카메라 기반 장애물검출)

  • Seo, Joonho;Kim, Chang Won
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.22 no.7
    • /
    • pp.552-556
    • /
    • 2016
  • Obstacle detection is a key feature in the safe driving control of electric wheelchairs. The suggested obstacle detection algorithm was designed to provide obstacle avoidance direction and detect the existence of cliffs. By means of this information, the wheelchair can determine where to steer and whether to stop or go. A 3D depth camera (Microsoft KINECT) is used to scan the 3D point data of the scene, extract information on obstacles, and produce a steering direction for obstacle avoidance. To be specific, ground detection is applied to extract the obstacle candidates from the scanned data and the candidates are projected onto a 2D map. The 2D map provides discretized information of the extracted obstacles to decide on the avoidance direction (left or right) of the wheelchair. As an additional function, cliff detection is developed. By defining the "cliffband," the ratio of the predefined band area and the detected area within the band area, the cliff detection algorithm can decide if a cliff is in front of the wheelchair. Vehicle tests were carried out by applying the algorithm to the electric wheelchair. Additionally, detailed functions of obstacle detection, such as providing avoidance direction and detecting the existence of cliffs, were demonstrated.

Obstacle Avoidance Method for Multi-Agent Robots Using IR Sensor and Image Information (IR 센서와 영상정보를 이용한 다 개체 로봇의 장애물 회피 방법)

  • Jeon, Byung-Seung;Lee, Do-Young;Choi, In-Hwan;Mo, Young-Hak;Park, Jung-Min;Lim, Myo-Taeg
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.18 no.12
    • /
    • pp.1122-1131
    • /
    • 2012
  • This paper presents obstacle avoidance method for scout robot or industrial robot in unknown environment by using IR sensor and vision system. In the proposed method, robots share the information where the obstacles are located in real-time, thus the robots can choose the best path for obstacle avoidance. Using IR sensor and vision system, multiple robots efficiently evade the obstacles by the proposed cooperation method. No landmark is used at wall or floor in experiment environment. The obstacles don't have specific color or shape. To get the information of the obstacle, vision system extracts the obstacle coordinate by using an image labeling method. The information obtained by IR sensor is about the obstacle range and the locomotion direction to decide the optimal path for avoiding obstacle. The experiment was conducted in $7m{\times}7m$ indoor environment with two-wheeled mobile robots. It is shown that multiple robots efficiently move along the optimal path in cooperation with each other in the space where obstacles are located.

A robot motion planning method for time-varying obstacle avoidance

  • Ko, Nak-Yong;Lee, Bum-Hee;Ko, Myoung-Sam
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.491-496
    • /
    • 1992
  • An analytic solution approach to the time-varying obstacle avoidance problem is pursued. We formulate the problem in robot joint space(JS), and introduce the view-time concept to deal with the time-varying obstacles. The view-time is a set of continuous times in which a time-varying obstacle is viewed and approximated by an equivalent stationary obstacle. The equivalent stationary obstacle is transformed into the JS obstacle. In JS, the path and trajectory avoiding the JS obstacle is planned.

  • PDF

A Study on the Method of Estimating the Baseline Risk Level of Multiple Obstacles situation Avoidance Based on COLREG for each Obstacles (다중 장애물 상황에서 COLREG를 바탕으로 장애물 회피의 기초 위험도 산정 방법에 관한 연구)

  • Kim, Dae-Hui
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
    • /
    • /
    • pp.195-196
    • /
    • 2019
  • Studied for multiple obstacle avoidance algorithm based on COLREG for autonomous navigation vessel's safety navigation. By used VECTOR value of external obstacle provided by RADAR, CPA and TCPA of each obstacle are analyzed, and the obstacle is classified based on the value, the risk level is calculated considering multiple obstacle avoidance situations, and the avoidance action is applied to secure minimum safety situation.

  • PDF

Study on the Collision Avoidance of a Redundant Robot Arm Using Fuzzy Control (퍼지 제어기를 이용한 여유자유도 로봇 팔의 장애물 우회에 관한 연구)

  • 황재석;박찬호;이병룡;양순용;안경관
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • /
    • pp.345-348
    • /
    • 1997
  • In this paper, a motion control algorithm is developed using a fuzzy control and the optimization of performance function, which makes a robot arm avoid an unexpected obstacle when the end-effector of the robot arm is moving to the goal position. During the motion, if there exists no obstacle, the end-effecter of the robot arm moves along the pre-defined path. But if there exists an obstacle and close to the robot arm, the fuzzy motion controller is activated to adjust the path of the end-effector of the robot arm. Then, the robot arm takes the optimal posture for collision avoidance with the obstacle. To show the feasibility of the developed algorithm, numerical simulations are carried out with changing both the positions and sizes of obstacles. It was concluded that the proposed algorithm gives a good performance for obstacle avoidance.

  • PDF