• The Journal of Korea Robotics Society
• /
• v.10 no.1
• /
• pp.42-51
• /
• 2015

Peg-in-hole assembly is the most representative task for a robot to perform under contact conditions. Various strategies for accomplishing the peg-in-hole task with a robot exist, but the existing strategies are not sufficiently practical to be used for various assembly tasks in a human environment because they require additional sensors or exclusive tools. In this paper, the peg-in-hole assembly experiment is performed with anthropomorphic hand arm robot without extra sensors or devices using "intuitive peg-in-hole strategy". From this work, the probability of applying the peg-in-hole strategy to a common assembly task is verified.

• Journal of Biomedical Engineering Research
• /
• v.33 no.3
• /
• pp.105-113
• /
• 2012

Biopsy is a type of histopathological examinations, in which a physician samples cells or tissues from a patient's suspicious lesion. Such a lesion frequently resides deep inside human body, and then a percutaneous biopsy is therefore performed using a thick needle with the assistance of medical imaging such as computed tomography(CT) and magnetic resonance imaging(MRI). Recently modern robotic technology is being introduced to percutaneous biopsy in order to reduce any possible human error and hazard on physicians caused by medical imaging. After medical imaging locates the exact location of lesion, an optimization algorithm plans the path for a biopsy needle. Subsequently, a robot system moves the biopsy needle to the lesion in accurate and safe way with the control of a practitioner or automatically. In this article, we try to look into the state-of-art of percutaneous biopsy using such robotic technology. We classified percutaneous biopsy robots by mechanical characteristics and by imaging technology. Then, advantage and disadvantage of each class type are described as well as the basic description, and a few representative designs for each type are introduced. Current research issues of robotized percutaneous biopsy are subjectively selected for the readers' convenience. We emphasize the basic technology of actuator and sensors compatible with imaging technology to conclude this review.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.7 no.6
• /
• pp.57-63
• /
• 1998

An adaptive control in the robotic GMA welding is employed to monitor information about weld characteristics and process parameters as well as to modify those parameters to hold weld quality within acceptable limits. Typical characteristics are the bead geometry, composition, microstructure, appearance, and process parameters which govern the quality of the final weld. The main objectives of this thesis are to realize the mapping characteristics of bead width through learning. After learning, the neural estimation can estimate the bead width desired form the learning mapping characteristic. The design parameters of the neural network estimator(the number of hidden layers and the number of nodes in a layer) are chosen from an estimation error analysis. A series of bead of bead-on-plate GMA welding experiments was carried out in order to verify the performance of the neural network estimator. The experimental results show that the proposed neural network estimator can predict the bead width with reasonable accuracy and guarantee the uniform weld quality.

• Journal of Institute of Control, Robotics and Systems
• /
• v.1 no.2
• /
• pp.88-93
• /
• 1995

This paper presents a study using neural networks in the design of the tracking controller of robotic systems. Our strategy is to put to use the available knowledge about the robot manipulator, such as estimation models, in the contoller design via the computed torque method, and then to add the neural network to control the remaining uncertainty. The neural network used here learns to provide the inverse dynamics of the plant uncertainty, and acts as an inverse controller. In the simulation study, we verify that the proposed neural network controller is robust not only to structured uncertainties, but also to unstructured uncertainties such as friction models.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2009.04a
• /
• pp.129-132
• /
• 2009

Automatic target recognition surveying method is very important technology one-man surveying system. But in the case of loss of prism's position, it have to be re-tracking for searching it, consuming the searching time and complicated in processing. In this study, it is proposed new GPS receiver combination technology for orientation of both. In conclusion, the robotic TS(totalstation) is well assisted by absolute coordinates from single GPS receiver and multi-functional surveying instrument.

• Journal of Korean Institute of Industrial Engineers
• /
• v.23 no.2
• /
• pp.249-260
• /
• 1997

The manufacturing environment is rife with nonlinear processes. In this context, an intelligent production controller should be able to predict the dynamic behavior of various subsystems as they react to transient environmental conditions, the varying internal condition of the manufacturing plant, and the changing demands of the production schedule. This level of adaptive capability may be achieved through a coherent methodology for a learning coordinator to predict nonlinear and stochastic processes. The system is to serve as a real time, online supervisor for routine activities as well as exceptional conditions such as damage, failure, or other anomalies. The complexity inherent in a learning coordinator can be managed by a modular architecture incorporating case based reasoning. In the interest of concreteness, the concepts are presented through a case study involving a knowledge based robotic system.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.5 no.4
• /
• pp.26-37
• /
• 1996

This paper presents a new approach to the design of adaptive control system using DSPs(TMS320C30) for robotic manipulators to achieve trajectory tracking by the joint angles Digital signal processors are used in implementing real time adaptive control algorithms to provide an enhanced motion control for robotic manipulators. In the proposed control scheme adaptation laws are derived from the improved Lyapunov second stability analysis method based on the adaptive model reference control theory. The adaptive controller consists of an adaptive feedforward controller. feedback controller. and PID type time-varying auxiliary control elements. The proposed adaptive control scheme is simple in structure, fast in computation, and suitable for implementation of real-time control. Moreover, this scheme does not require a an accurate dynamic modeling, nor values of manipulator parameters and payload. Performance of the adaptive controller is illustrated by simulation and experimental results for a SCARA robot.

• International Journal of Control, Automation, and Systems
• /
• v.6 no.1
• /
• pp.101-108
• /
• 2008

The transposed Jacobian is proposed to transform the control space from task space to joint space, in this paper. Instead of inverse Jacobian, the transposed Jacobian is preferred to avoid singularity problem, short real time calculations and its generality to apply for rectangular Jacobian. On-line Jacobian identification is proposed to cancel parametric errors produced by D-H parameters of manipulator. To identify Jacobian, the joint angles and the end-effector position are measured when tracking a desired trajectory in task space. Stability of control system is analyzed. The control system is simulated for position control of a two-link manipulator driven by permanent magnet dc motors. Simulation results are shown to compare the roles of inverse Jacobian and transposed Jacobian for transforming the control space.

• Journal of Mechanical Science and Technology
• /
• v.19 no.6
• /
• pp.1268-1279
• /
• 2005

The current method for pavement sign marking operations is labor-intensive and very dangerous due to the exposure of workers to passing traffic. It also requires blocking traffic for a long period of time resulting serious traffic jam. This paper deals with the development of a robotic system for automating the pavement sign painting operations. The robotic system consists of gantry frame equipped with transverse drive rail and automatic paint spray system. The workspace of the gantry robot is extended to one-lane width with the transverse rail system. This research also includes the development of font data structures that contain the shape information of pavement signs, such as Korean letters, English letters and symbols. The robot path is generated with this font data through the procedures of scaling up/down and partitioning the signs to be painted depending on the workspace size.

• Proceedings of the Korea Multimedia Society Conference
• /
• 2004.05a
• /
• pp.770-773
• /
• 2004

IT(Information Technology)분야의 발전과 함께 RT(Robot Technology)분야도 21세기의 유망한 첨단기술로 손꼽히고 있다. 현재의 로봇은 그동안 주류를 이루던 산업용 로봇과는 달리 소프트컴퓨팅, 인간친화 인터페이스, 상호작용기술, 음성인식, 물체인식, 사용자 의도파악 등 갖가지 최첨단 기술들이 요구되는 퍼스널 로봇이 각광을 받고 있으며, 특히 오락용, 교육용 로봇들로 대표되는 엔터테인먼트 로봇(Entertainment Robot)분야가 요즘 국내·외에서 활발히 연구되고 있는 실정이다. 엔터테인먼트 로봇은 정형화된 작업만을 하는 것이 아니라 다양한 환경에서 여러 가지 작업을 해야만 한다. 따라서, 장난감 로봇처럼 인간과의 감정대화가 가능한 지능 시스템을 갖춰야만 한다. 그러므로 본 논문에서는 IT분야와 RT분야의 접목으로 시너지 효과를 크게 얻을 수 있는 새로운 기술 개념인 RCP(Robotic Cellular Phone)에 대한 개념을 정의하고, RCP의 기능성 모듈 중 하나인 감성발향 모듈에 대한 기본적인 이론과 실험적 결과를 통하여 로보틱 셀폰의 감성발향 모듈의 우수성을 확인한다.