• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2435-2437
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• 2004

In this paper, an obstacle avoidance algorithm is proposed for a network-based robot considering network delay by distribution. The proposed algorithm is based on the VFH(Vector Field Histogram) algorithm, and for the network-based robot system, in which it is assumed robot localization information is transmitted through network communication. In this paper, target vector for the VFH algorithm is estimated through the robot localization information and the measurement of its delay by distribution. The delay measurement is performed by time-stamp method. To synchronize all local clocks of the nodes distributed on the network, a global clock synchronization method is adopted. With the delay measurement, the robot localization estimation is performed by calculating the kinematics of the robot. The validation of the proposed algorithm is performed through the performance comparison of the obstacle avoidance between the proposed algorithm and the existing VFH algorithm on the network-based autonomous mobile robot.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.434-439
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• 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'.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.3
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• pp.264-268
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• 2006

In this paper, we construct the infrastructure with wireless LAN for the teleoperating system of mobile robots. For the stable teleoperating system, we develope an algorithm that measure communication time delay on real-time. We propose the force-reflected teleoperation method that control the stiffness of joystick according to VFH(Vector Field Histogram). Also, an obstacle avoidance method using VFH is presented for the mobile robot to move to the indicated direction without collision. Experiments are conducted to demonstrate the feasibility of the proposed methods.

• Proceedings of the KIEE Conference
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• 2006.07d
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• pp.1983-1986
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• 2006

In this paper, we construct the infrastructure for the teleoperating system of mobile robots. For the stable teleoperating system, we develope an algorithm that measure communication time delay on real-time. We propose the force-reflected teleoperation method that control the stiffness of joystick according to VFH(Vector Field Histogram). Also, an obstacle avoidance method using VFH is presented for the mobile robot to move to the indicated direction without collision. Experiments are conducted to demonstrate the feasibility of the proposed methods.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2461-2466
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• 2003

This paper presents a simple sensor fusion algorithm using neural network for navigation of mobile robots with obstacle avoidance and trap recovery. The multiple sensors input sensor data to the input layer of neural network activating the input nodes. The multiple sensors used include optical encoders, ultrasonic sensors, infrared sensors, a magnetic compass sensor, and GPS sensors. The proposed sensor fusion algorithm is combined with the VFH(Vector Field Histogram) algorithm for obstacle avoidance and AGPM(Adaptive Goal Perturbation Method) which sets adaptive virtual goals to escape trap situations. The experiment results show that the proposed low-level fusion algorithm is effective for real-time navigation of mobile robot.