• Title, Summary, Keyword: obstacle avoidance

Search Result 545, Processing Time 0.047 seconds

A New Approach of BK products of Fuzzy Relations for Obstacle Avoidance of Autonomous Underwater Vehicles

  • Bui, Le-Diem;Kim, Yong-Gi
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.4 no.2
    • /
    • pp.135-141
    • /
    • 2004
  • This paper proposes a new heuristic search technique for obstacle avoidance of autonomous underwater vehicles equipped with a looking ahead obstacle avoidance sonar. We suggest the fuzzy relation between the sonar sections and the properties of real world environment. Bandler and Kohout's fuzzy relational method are used as the mathematical implementation for the analysis and synthesis of relations between the partitioned sections of sonar over the real-world environmental properties. The direction of the section with optimal characteristics would be selected as the successive heading of AUVs for obstacle avoidance. For the technique using in this paper, sonar range must be partitioned into multi equal sections; membership functions of the properties and the corresponding fuzzy rule bases are estimated heuristically. With the two properties Safety, Remoteness and sonar range partitioned in seven sections, this study gives the good result that enables AUVs to navigate through obstacles in the optimal way to goal.

Experimental Verification of Obstacle Avoidance Algorithm ELA Applicable to Rescue Robots (구조로봇에 적합한 장애물 회피 알고리즘 ELA의 실험적 검증)

  • Jeong, Hae-Kwan;Hyun, Kyung-Hak;Kim, Soo-Hyun;Kwak, Yoon-Keun
    • The Journal of Korea Robotics Society
    • /
    • v.4 no.2
    • /
    • pp.105-111
    • /
    • 2009
  • In this paper, we provide experimental results and verification for obstacle avoidance algorithm 'ELA(Emergency Level Around)', which is applicable to rescue robots. ELA is a low level intelligence-based obstacle avoidance algorithm, so can be used in fast mobile robots requiringhigh speed in operation with little computational load. Constructed system for experiments consist of laptop, sensors, peripheral devices and mobile robot platform VSTR(Variable Single-tracked Robot) to realize predetermined scenarios. Finally, experiment was conducted in indoor surroundings including miscellaneous things as well as dark environment to show fitness and robustness of ELA for rescue, and it is shown that VSTR navigates endowed area well with real-time obstacle avoidance based on ELA. Therefore, it is concluded that ELA can be a candidate algorithm to increase mobility of rescue robots in real situation.

  • PDF

Obstacle Avoidance Algorithm using Stereo (스테레오 기반의 장애물 회피 알고리듬)

  • Kim, Se-Sun;Kim, Hyun-Soo;Ha, Jong-Eun
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.15 no.1
    • /
    • pp.89-93
    • /
    • 2009
  • This paper deals with obstacle avoidance for unmanned vehicle using stereo system. The "DARPA Grand Challenge 2005" shows that the robot can move autonomously under given waypoint. RADAR, IMS (Inertial Measurement System), GPS, camera are used for autonomous navigation. In this paper, we focus on stereo system for autonomous navigation. Our approach is based on Singh et. al. [5]'s approach that is successfully used in an unmanned vehicle and a planetary robot. We propose an improved algorithm for obstacle avoidance by modifying the cost function of Singh et. al. [5]. Proposed algorithm gives more sharp contrast in choosing local path for obstacle avoidance and it is verified in experimental results.

Obstacle Avoidance of Mobile Robot Using Distributed Fuzzy Control with Imitation of Potential Field (Potential Field 모방 분산 퍼지 제어를 통한 이동 로봇의 장애물 회피)

  • Kwak, Hwan-Joo;Park, Gwi-Tae
    • Proceedings of the IEEK Conference
    • /
    • /
    • pp.378-380
    • /
    • 2009
  • For the autonomous movement, the optimal pat]1 planning connecting between current and target positions is essential, and the optimal path of mobile robot means obstacle-free and the shortest length path to a target position. Many actual mobile robots should move without any information of surrounded obstacles. This paper suggests a new method of obstacle avoidment which is suitable in unknown environments. This method of obstacle avoidance is designed with a distributed fuzzy control system, and imitates a Potential Field method. A simulation confirms the performance and correctness of the obstacle avoidance.

  • PDF

A Study on Stable Motion Control of Biped Robot with 18 Joints (18관절 2족보행 로봇의 안정한 모션제어에 관한연구)

  • Park, Youl-Moon;Thu, Le Xuan;Won, Jong-Beom;Park, Sung-Jun;Kim, Yong-Gil
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.17 no.2
    • /
    • pp.35-41
    • /
    • 2014
  • This paper describes the obstacle avoidance architecture to walk safely around in factory and home environment, and presents methods for path planning and obstacle avoidance for the humanoid robot. Solving the problem of obstacle avoidance for a humanoid robot in an unstructured environment is a big challenge, because the robot can easily lose its stability or fall down if it hits or steps on an obstacle. We briefly overview the general software architecture composed of perception, short and long term memory, behavior control, and motion control, and emphasize on our methods for obstacle detection by plane extraction, occupancy grid mapping, and path planning. A main technological target is to autonomously explore and wander around in home environments as well as to communicate with humans.

Collaborative Obstacle Avoidance Method of Surface and Aerial Drones based on Acoustic Information and Optical Image (음향정보 및 광학영상 기반의 수상 및 공중 드론의 협력적 장애물회피 기법)

  • Man, Dong-Woo;Ki, Hyeon-Seung;Kim, Hyun-Sik
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.64 no.7
    • /
    • pp.1081-1087
    • /
    • 2015
  • Recently, the researches of aerial drones are actively executed in various areas, the researches of surface drones and underwater drones are also executed in marine areas. In case of surface drones, they essentially utilize acoustic information by the sonar and consequently have the local information in the obstacle avoidance as the sonar has the limitations due to the beam width and detection range. In order to overcome this, more global method that utilizes optical images by the camera is required. Related to this, the aerial drone with the camera is desirable as the obstacle detection of the surface drone with the camera is impossible in case of the existence of clutters. However, the dynamic-floating aerial drone is not desirable for the long-term operation as its power consumption is high. To solve this problem, a collaborative obstacle avoidance method based on the acoustic information by the sonar of the surface drone and the optical image by the camera of the static-floating aerial drone is proposed. To verify the performance of the proposed method, the collaborative obstacle avoidances of a MSD(Micro Surface Drone) with an OAS(Obstacle Avoidance Sonar) and a BMAD(Balloon-based Micro Aerial Drone) with a camera are executed. The test results show the possibility of real applications and the need for additional studies.

Development of Vision based Autonomous Obstacle Avoidance System for a Humanoid Robot (휴머노이드 로봇을 위한 비전기반 장애물 회피 시스템 개발)

  • Kang, Tae-Koo;Kim, Dong-Won;Park, Gwi-Tae
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.60 no.1
    • /
    • pp.161-166
    • /
    • 2011
  • This paper addresses the vision based autonomous walking control system. To handle the obstacles which exist beyond the field of view(FOV), we used the 3d panoramic depth image. Moreover, to decide the avoidance direction and walking motion of a humanoid robot for the obstacle avoidance by itself, we proposed the vision based path planning using 3d panoramic depth image. In the vision based path planning, the path and walking motion are decided under environment condition such as the size of obstacle and available avoidance space. The vision based path planning is applied to a humanoid robot, URIA. The results from these evaluations show that the proposed method can be effectively applied to decide the avoidance direction and the walking motion of a practical humanoid robot.

Unmanned Ground Vehicle Control and Modeling for Lane Tracking and Obstacle Avoidance (충돌회피 및 차선추적을 위한 무인자동차의 제어 및 모델링)

  • Yu, Hwan-Shin;Kim, Sang-Gyum
    • Journal of Advanced Navigation Technology
    • /
    • v.11 no.4
    • /
    • pp.359-370
    • /
    • 2007
  • Lane tracking and obstacle avoidance are considered two of the key technologies on an unmanned ground vehicle system. In this paper, we propose a method of lane tracking and obstacle avoidance, which can be expressed as vehicle control, modeling, and sensor experiments. First, obstacle avoidance consists of two parts: a longitudinal control system for acceleration and deceleration and a lateral control system for steering control. Each system is used for unmanned ground vehicle control, which notes the vehicle's location, recognizes obstacles surrounding it, and makes a decision how fast to proceed according to circumstances. During the operation, the control strategy of the vehicle can detect obstacle and perform obstacle avoidance on the road, which involves vehicle velocity. Second, we explain a method of lane tracking by means of a vision system, which consists of two parts: First, vehicle control is included in the road model through lateral and longitudinal control. Second, the image processing method deals with the lane tracking method, the image processing algorithm, and the filtering method. Finally, in this paper, we propose a method for vehicle control, modeling, lane tracking, and obstacle avoidance, which are confirmed through vehicles tests.

  • PDF

A New Method for Local Obstacle Avoidance of a Mobile Robot (이동 로봇의 지역 장애물 회피를 위한 새로운 방법)

  • 김성철
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • /
    • pp.88-93
    • /
    • 1998
  • This paper presents a new solution approach to moving obstacle avoidance problem for a mobile robot. A new concept avoidability measure(AVM) is defined to describe the state of a pair of a robot and an obstacle regarding the collision between them. As an AVM, virtual distance function(VDF) is derived as a function of the distance from the obstacle to the robot and outward speed of the obstacle relative to the robot. By keeping the virtual distance above some positive limit value, the robot avoids the obstacle. In terns of the VDF, an artificial potential field is constructed to repel the robot away from the obstacle and to attract the robot toward a goal location. At every sampling time, the artificial potential field is updated and the force driving the robot is derived form the gradient of the artificial potential field. The suggested algorithm drives the robot to avoid moving obstacles in real time. Since the algorithm considers the mobility of the obstacle as well as the distance, it is effective for moving obstacle avoidance. Some simulation studies show the effectiveness of the proposed approach.

  • PDF

Goal-directed Obstacle Avoidance Using Lane Method (레인 방법에 기반한 이동 로봇의 장애물 회피)

  • Do, Hyun-Min;Kim, Yong-Shik;Kim, Bong-Keun;Lee, Jae-Hoon;Ohba, Kohtaro
    • The Journal of Korea Robotics Society
    • /
    • v.4 no.2
    • /
    • pp.121-129
    • /
    • 2009
  • This paper presents a goal-directed reactive obstacle avoidance method based on lane method. The reactive collision avoidance is necessarily required for a robot to navigate autonomously in dynamic environments. Many methods are suggested to implement this concept and one of them is the lane method. The lane method divides the environment into lanes and then chooses the best lane to follow. The proposed method does not use the discrete lane but chooses a line closest to the original target line without collision when an obstacle is detected, thus it has a merit in the aspect of running time and it is more proper for narrow corridor environment. If an obstacle disturbs the movement of a robot by blocking a target path, a robot generates a temporary target line, which is parallel to an original target line and tangential to an obstacle circle, to avoid a collision with an obstacle and changes to and follows that line until an obstacle is removed. After an obstacle is clear, a robot returns to an original target line and proceeds to the goal point. Obstacleis recognized by laser range finder sensor and represented by a circle. Our method has been implemented and tested in a corridor environment and experimental results show that our method can work reliably.

  • PDF