• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
• /
• pp.113-118
• /
• 1993

This paper represents mechanical compliance & ZMP(Zero Moment Point) control algorithm for IWR(Inha Walking Robot) system. In case of walking in different environments, a biped walking robot must vary its gait(walking period or step length, etc.) according to the environments. However, most of biped walking robots do not have the capability to change their gaits or need more complex control algorithm, because ZMP cannot be defined in their control algorithm. Therefore new linear type with balancing joint is proposed which is used as an aid in balancing & ZMP control itself. In IWR system, ZMP can be defined by solving differential equations and it does not need to be predefined ZMP trajectory. Furthermore we can input the desired ZMP position. In parallel with the development, we also considered a mechanical compliance for reducing the inverse kinematics, dynamics and the control complexity. It will figure out some powerful adaptation with 3D irregular terrains.

• International Journal of Control, Automation, and Systems
• /
• 제6권3호
• /
• pp.386-393
• /
• 2008

A position control method for interpolating aspherical grinding and polishing tool path was reviewed and experimented in a nano precision machine. The position-base algorithm was reformed from the time-base algorithm, proposed in the previous study. The characteristics of the algorithm were in the velocity control loop with position feedback. The aspherical surface was divided by an interval at which each velocity and acceleration were calculated. The theoretical velocity was corrected by position error during processing. In the experiment, a machine was constructed and nano-scale linear encoders were installed at each axis. Relation between process parameters and the variation of position error was monitored and discussed. The best result from optimized parameters showed that the accuracy was 150nm and improved from the previous report.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
• /
• pp.896-899
• /
• 1996

A new algorithm for planning a collision free path is developed based on linear parametric curve. A collision-free path is viewed as a connected space curve in which the path consists of two straight curve connecting start to target point. A single intermediate connection point is considered in this paper and is used to manipulate the shape of path by organizing the control point in polar coordinate (.theta.,.rho.). The algorithm checks interference with obstacles, defined as GM (Geometry Mapping), and maps obstacles in Euclidean Space into images in CPS (Connection Point Space). The GM for all obstacles produces overlapping images of obstacle in CPS. The clear area of CPS that is not occupied by obstacle images represents collision-free paths in Euclidean Space. Any points from the clear area of CPS is a candidate for a collision-free path. A simulation of GM for number of cases are carried out and results are presented including mapped images of GM and performances of algorithm.

• 제어로봇시스템학회논문지
• /
• 제17권9호
• /
• pp.922-931
• /
• 2011

An efficient calibration algorithm for mobile robot localization using infrared range finder is proposed. A calibration is important to guarantee the performance of other algorithms which use sensor data because it is pre-process. We experimentally found that the infrared range finder PBS-03JN has error characteristics depending on both distance and scan angle. After obtaining 2-D grid error characteristic data on distance and scan angle, we proposed a simple and efficient calibration algorithm with a 2-D piecewise linear function set. The performance of our proposed calibration algorithm is verified by experiments and simulation.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
• /
• pp.154-159
• /
• 1989

This paper presents a motion planning algorithm for conveyor tracking. We formulate the problem as the linear quadratic tracking problem in optimal control theory and solve it through dynamic programming. In the proposed algorithm, the steady-state tracking error is eliminated completely, and the joint torque, velocity, acceleration, and jerks are considered as some constraints. Numerical examples are then presented to demonstrate the utility of the proposed motion planning algorithm.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1998년도 하계학술대회 논문집 B
• /
• pp.581-584
• /
• 1998

This paper presents a scheme for fuzzy modelling and control of continuous-time nonlinear systems using a genetic algorithm. A fuzzy model is characterized by fuzzy "if-then" rules whose consequence part has a linear dynamic equation as subsystem of the system. The parameters of the fuzzy model are adjusted by a genetic algorithm. Then a tracking controller which guarantees stability of the overall system is designed. The simulation result demonstrates the effectiveness of the proposed method.

• 대한전자공학회논문지SP
• /
• 제42권6호
• /
• pp.63-72
• /
• 2005

본 논문에서는 H.263, H.263+, MPEG-4와 같은 블록 기반 비디오 압축을 위한 비트-율 제어 기법을 제안한다. 제안 알고리즘은 선형 모델에 기반한 라그랑지안 최적화 기법을 통해서 매크로블록 당 할당되는 양자화 파라미터의 조합을 산출한다. 제안 알고리즘에 사용하는 라그랑지안 비용함수는 선형 모델에 의해서 산출되는 비트-율과 왜곡을 통해 구한다. H.263과 MPEG-4의 양자화 파라미터를 부호화하는 Dquant 방법에 맞도록 하기 위해 Dquant 방법을 고려하면서 동시에 라그랑지안 최적화 기법에 의한 해를 구하는 비터비 알고리즘에 의해 양자화 파라미터 조합을 구한다. 제안 알고리즘은 모델 기반 비트-율 제어 기법 중 하나인 TMN8 기법에 비해 1.5 dB 정도의 비디오 화질 개선 효과를 가지며, 선형 모델 기반 비트-율 제어 기법인 일정화질 접근 방법에 비해 화질은 거의 동일하게 유지하면서 비트-율의 변동폭이 줄어드는 효과가 있다.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
• /
• pp.1185-1188
• /
• 1996

In this paper we present a genetic approach for trajectory control algorithm of balancing weight for IWR biped walking robot. The biped walking robot, IWR that was made by Automatic Control Lab. of Inha University has a trunk which stabilizes its walking by generating compensation moment. Trunk is composed of a revolute and a prismatic joint which roles balancing weight. The motion of balancing weight is determined by the gait of legs and represented by two linear second order ordinary differential equations. The solution of this equation must satisfy some constraints simultaneously to have a physical meaning. Genetic algorithm search for this feasible motion of balancing weight under some constraints. Simulation results show that feasible motion of balancing weight can be obtained by genetic algorithm.

• 대한공간정보학회지
• /
• 제5권2호
• /
• pp.29-43
• /
• 1997

ITS 구축을 위한 고속도로축 통합최적제어모형은 진입램프미터링, 진출램프전환율 그리고 인접노면가로 g/C비 결정 등 3가지 제어 변수를 동시에 결정될 수 있도록 구축하였다. 또한 실시간 처리가 가능하도록 당초 비선형문제를 선형문제로 전환하기 위해 교통밀도 관계식을 두 개의 선형함수로 축약하고, SLP알고리즘을 사용한 컴퓨터 알고리즘도 제안하였다.

• 한국정보전자통신기술학회논문지
• /
• 제12권4호
• /
• pp.434-439
• /
• 2019

본 논문에서는 신호 대 잡음비를 향상시키기 위해서 시간지연을 보상하는 제어 알고리즘을제안하고, 제안한 제어 알고리즘을 연속파 레이더 방정식에 적용하여 목표물의 정보를 추정한다. 제안한 제어 알고리즘은 신호 대 잡음비를 향상시키기 위해서 수신신호에 가중치를 곱하여 각 배열소자의 출력신호를 향상시킨다. 레이더는 공간상에 신호를 방사하고 불체로부터 반사된 신호를 수신하여 정보를 추출한다. 그러나 무선통신환경에서는 인공 및 자연구조물로 인해서 다중 경로현상이 발생되어 시호의 시간지연이 나타나게 된다. 시간지연은 간섭신호 및 신호왜곡 현상으로 시스템 성능이 저하되어 원하는 정보를 정확히 추정하기 어렵다. 본 연구에서는 등 간격 선형 배열 안테나를 사용하여 수신신호에 가중치로 지연신호를 보상함으로서 목표물의 추정 정보를 향상 시킬 수 있다. 모의실험으로 본 연구에서 제안한 제어 알고리즘과 지연시간이 보상되지 않은 방법에 대해서 성능을 비교 분석하였으며 본 연구에서 제안한 제어 알고리즘이 원하는 목표물 거리추정 정보가 향상되었음을 입증하였다.