• 한국정보통신학회논문지
• /
• 제19권1호
• /
• pp.26-34
• /
• 2015

본 논문에서는 이동 로봇의 군집 제어를 위해 퍼지 보상된 PID 제어 시스템을 제안한다. 제어 시스템은 선도-추종기법에 기반한 기구학 제어기와 이동 로봇의 동역학적 영향을 고려한 동역학 제어기로 구성되어 있다. 이동 로봇의 대형 유지를 위해 동역학 제어기는 PID제어기로 구성되었다. 하지만 PID 제어기는 비선형 또는 환경 변화에 취약점을 가진다. 이러한 문제를 보완하기 위해 퍼지 보상기를 추가하였다. 마지막으로 개선된 성능을 보이기 위해 컴퓨터 시뮬레이션을 통해 제안된 제어기를 평가하였다.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
• /
• pp.449-452
• /
• 1996

In this paper, a robust.adaptive control scheme is presented for precise trajectory tracking of nonholonomic mobile robots. In the controller, a set of desired trajectory is defined and used in constructing the control input which constitutes the main part of the proposed controller. The stable operating characteristics such as precise trajectory tracking, parameter estimation, disturbance suppression, tec., are shown through experiments as well as computer simulation.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
• /
• pp.1177-1180
• /
• 1996

In this paper, we propose an algorithm that realizes cooperative behavior by construction of autonomous mobile robot system. Each robot is able to sense other robots and obstacles, and it has the rule of behavior to achieve the goal of the system. In this paper, to improve performance of the whole system, we use Genetic Programming based on Natural Selection. Genetic Programming's chromosome is a program of tree structure and it's major operators are crossover and mutation. We verify the effectiveness of the proposed scheme from the several examples.

• 로봇학회논문지
• /
• 제17권2호
• /
• pp.183-190
• /
• 2022

Accurate kinematic parameters of mobile robots are essential because inaccurate kinematic model produces considerable uncertainties on its odometry and control. Especially, kinematic parameters of caster type mobile robots are important due to their complex kinematic model. Despite the importance of accurate kinematic parameters for caster type mobile robots, few research dealt with the calibration of the kinematic model. Previous study proposed a calibration method that can only calibrate double-wheeled caster type mobile robot and requires direct-measuring of robot center point and distance between casters. This paper proposes a calibration method based on geometric approach that can calibrate single-wheeled caster type mobile robot with two or more casters, does not require direct-measuring, and can successfully acquire all kinematic parameters required for control and odometry. Simulation and hardware experiments conducted in this paper validates the proposed calibration method and shows its performance.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2001년도 ICCAS
• /
• pp.104.3-104
• /
• 2001

This paper develops a control approach to generic formation tasks of multiple mobile robots with inaccurate sensor information. Inaccurate sensor information means that all the robots have only local sensors which cannot accurately measure absolute distances and directions of objects. The control logic is developed considering generic situations in order to adapt to increasing number of robots which participate in the formation. Petri nets are used for modeling and design of the control logic, which can visualize the control models and make it easy to check the states of each robot. Physically homogenous mobile robots are designed and built to evaluate the developed logic. Each robot is equipped with eighteen infrared sensors and a UHF transceiver module. The developed control ...

• 전기학회논문지
• /
• 제60권2호
• /
• pp.389-397
• /
• 2011

The global dynamic window approach (DWA) is widely used to generate the shortest path of mobile robots considering obstacles and kinematic constraints. However, the dynamic constraints of robots should be considered to generate the minimum-time path. We propose a modified global DWA considering the dynamic constraints of robots. The reference path is generated using A* algorithm and smoothed by cardinal spline function. The trajectory is then generated to follows the reference path in the minimum time considering the robot dynamics. Finally, the local path is generated using the dynamic window which includes additional terms of speed and orientation. Simulation and experimental results are presented to verify the performance of the proposed method.

• 전기학회논문지
• /
• 제66권1호
• /
• pp.114-120
• /
• 2017

The work present in this paper deals with a navigation problem for multiple mobile robots in unknown indoor environments. The environments are completely unknown to the robots; thus, proximity sensors installed on the robots' bodies must be used to detect information about the surroundings. The environments simulated in this work are dynamic ones which contain not only static but also moving obstacles. In order to guide the robot to move along a collision-free path and reach the goal, this paper presented a navigation method based on fuzzy approach. Then genetic algorithms were applied to optimize the membership functions and rules of the fuzzy controller. The simulation results verified that the proposed method effectively addresses the mobile robot navigation problem.

• Advances in robotics research
• /
• 제1권1호
• /
• pp.41-59
• /
• 2014

This paper deals with the problem of steering a group of mobile robots along a reference path while maintaining a desired geometric formation. To solve this problem, the overall formation is decomposed into numerous geometric patterns composed of pairs of robots, and the state of the geometric patterns is defined. A control algorithm for the problem is proposed based on the Nash equilibrium strategies incorporating receding horizon control (RHC), also known as model predictive control (MPC). Each robot calculates a control input over a finite prediction horizon and transmits this control input to its neighbor. Considering the motion of the other robots in the prediction horizon, each robot calculates the optimal control strategy to achieve its goals: tracking a reference path and maintaining a desired formation. The performance of the proposed algorithm is validated using numerical simulations.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
• /
• pp.819-824
• /
• 1997

This paper presents a cell-based motion control strategy for soccer playing mobile robots. In the central robot motion planner, the planar ground is divided into rectangular cells with variable sizes and motion indices to which direction the mobile robot should move. At every time the multiple objects-the goal gate, ball, and robots-detected, integer values of motion indices are assigned to the cells occupied by mobile robots. Once the indices being calculated, the most desirable state-action pair is chosen from the state and action sets to achieve successful soccer game strategy. The proposed strategy is computationally simple enough to be used for fast robotic soccer system.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2003년도 ICCAS
• /
• pp.818-829
• /
• 2003

A cooperating control algorithm for two nonholonomic mobile robots is proposed. The task is composed of collision avoidance against obstacles and carrying a ladder. The front robot and the rear robot are called the leader and the follower, respectively. Each robot has a nonholonomic constraint so it cannot move in perpendicular directions. The environment is initially supposed to be unknown except target position. The torque that drives leader is determined by distance between the leader and the target position or the distance between it and the obstacles. The torque by target is attractive and the torque by obstacles is repulsive. The two mobile robots are supposed to be connected by link that can be expanded and contracted. The follower computes its torque using position and orientation information from the leader by communication. Simulation results show that the robots can drive to target position without colliding into the obstacles and maintain the distance in the allowable range.