• 로봇학회논문지
• /
• 제4권1호
• /
• pp.25-33
• /
• 2009

One of the main problems of topological localization in a real indoor environment is variations in the environment caused by dynamic objects and changes in illumination. Another problem arises from the sense of topological localization itself. Thus, a robot must be able to recognize observations at slightly different positions and angles within a certain topological location as identical in terms of topological localization. In this paper, a possible solution to these problems is addressed in the domain of global topological localization for mobile robots, in which environments are represented by their visual appearance. Our approach is formulated on the basis of a probabilistic model called the Bayes filter. Here, marginalization of dynamics in the environment, marginalization of viewpoint changes in a topological location, and fusion of multiple visual features are employed to measure observations reliably, and action-based view transition model and action-associated topological map are used to predict the next state. We performed experiments to demonstrate the validity of our proposed approach among several standard approaches in the field of topological localization. The results clearly demonstrated the value of our approach.

• 로봇학회논문지
• /
• 제4권1호
• /
• pp.1-9
• /
• 2009

Radio Frequency Identification (RFID) is an automatic identification method. Information such as identification, logistics history, and specification of products are written and stored into the memory of RFID tags (that is, transponders), and retrieved through RF communication between RFID reader device and RFID tags. RFID systems have been applied to many fields of transportation, industry, logistics, environment, etc in order to improve business efficiency and reduce maintenance cost as well. Recently, some research results are announced in which RFID devices are combined with other sensors for mobile robot localization. In this paper, design of multi-protocol baseband for RFID reader device is proposed, and the baseband modem is implemented into SoC (System On a Chip). The baseband modem SoC for multi-protocol RFID reader is composed of several IP (Intellectual Property) blocks such as multi-protocol blocks, CPU, UART(Universal Asynchronous Receiver and Transmitter), memory, etc. As a result, the SoC implemented with FPGA(Field Programmable Gate Array) is applied to real product. It is shown that the size of RFID Reader module designed with the FPGA becomes smaller, and the SoC chip price for the same function becomes cheap. In addition, operation performance could be the same or better than that of the product with no SoC applied.

• Journal of Biosystems Engineering
• /
• 제31권1호
• /
• pp.52-58
• /
• 2006

Various robots were developed for harvesting fruits and vegetables. However, each robot was designed for a specific task such as harvesting apples or vegetables. This has been a big hurdle in application of robots to agriculture. A new type of hybrid manipulator with both parallel and serial joints was developed and designed to apply to various kinds of field operations. The hybrid manipulator had 2 extra degree of freedom in serial joints which made it flexible in switching one to the other type of hybrid manipulator, for example, PUMA to SCARA. And it was designed to harvest heavy fruits such as musky melons or water melons even behind leaves or branches of tree. This hybrid manipulator showed less than $\pm1mm$ position error. It was concluded that the hybrid manipulator was an effective and feasible tool to perform various works and to increase working performance.

• 한국콘텐츠학회논문지
• /
• 제18권7호
• /
• pp.322-329
• /
• 2018

원격제어는 명령을 전달하는 마스터 장치와 원격지에 위치한 로봇을 슬레이브로 간주하는 방식이다. 이러한 원격제어의 경우, 양 에이전트 간의 동특성, 전송속도 차이에 의해 가상환경을 이용한 가상 슬레이브를 통해 조작자가 원격제어의 특수성을 선행 수행하는 것이 일반적이다. 기존의 가상 슬레이브는 연산량의 한계에 의해 동역학적 효과를 제거한 그래픽 모델로 구성하는 것이 일반적이나 이는 원격지 로봇의 동특성이 무시되어 실제 원격제어시의 실재감을 살리기 어렵다. 본 논문에서는 로봇의 정동역학 모델을 이용하여 이를 원격제어에 활용하고, 가상 환경에서 상대적으로 느린 제어 주기에 의해 발생하는 정동역학의 수치오류를 보완하는 보상 기법을 제안하고 이를 실제 환경과의 원격제어와 비교하고자 한다.

• 한국산학기술학회논문지
• /
• 제9권4호
• /
• pp.871-877
• /
• 2008

Adaptive 아크 로봇 용접을 위한 용접 공정 변수와 용접 부 형상 사이에 상관관계를 조사하는 것은 중요한 일이다. 하지만 맞대기 용접의 공정에 있어 갭으로 인해 정확한 이면비드를 예측하는 것은 어려운 일이다. 본 연구에서는, 먼저 맞대기 용접을 통해 외부 용접 조건과 용접 비드 형상사이 상관관계가 규명되었고, 이를 응용하여 적절한 이면비드를 얻기 위한 개발이 이루어졌고, 이 연구결과는 산업 전 분야에 폭넓게 사용될 수도 있다. 다중회귀분석법이 공정변수 예측을 위한 연구방법으로 적용되었다. 예측방법의 결과들 또한 비교 및 분석이 이루어졌다.

• 한국군사과학기술학회지
• /
• 제11권1호
• /
• pp.5-14
• /
• 2008

In this paper, we propose operational concepts and technology requirements for guard and surveillance robots in military field. After surveying on current trend of guard robots, we present an operational scenario and technology requirements. To begin with, we discriminate the use of fixed type guard robots(fixed robots) and mobile guard and surveillance robots(mobile robots). Fixed robots are used for substituting daily guard by human soldier. In contrast, mobile robots are used for compensating shadow area where not to be covered by fixed type robots. To be specific, mobile robots adopt communication relays to extend operational range and sensor networks to collecting information. In addition, we present technology requirements composed of wireless communication system, platform, sensor nodes, unmanned driving technology, power supply system and IFF etc. In conclusion, in order to maximize co-operational functionality, fixed robots and mobile robots should be tightly related.

• 제어로봇시스템학회논문지
• /
• 제16권4호
• /
• pp.353-360
• /
• 2010

A skid-steering method which applied to the various mobile robot platforms currently shows its effectiveness in the specified field areas and purposes. This system contains however, several problems of its intrinsic properties such as slippages occurred by different moving direction between vehicle's driving and wheel's rotary and difficulties of driving performance control and so on. This paper deals with the suggestion of suitable control algorithm for 6WD/6WS skid steering wheeled vehicle and verified its feasibility by analyzing the behavior of 6WD/6WS skid-steered wheeled vehicle model and by applying the engineering analytical method to the considered mobile platform. The Performance of vehicle model is evaluated by using slip mode control to follow the steering input and, as a future work, this control algorithm could be applied to real 6WD/6WS in-wheel drive type vehicle finally.

• 한국공작기계학회논문집
• /
• 제14권1호
• /
• pp.95-100
• /
• 2005

Making the best use of the features of the electro-rheological(ER) valve, a two-port pressure control valve using ER fluids is proposed and manufactured. The ER-Valve characteristics are evaluated by changing the intensity of the electric field and the number of electrode. In addition, the performance of the plate type ER-Valve is investigated by change the particle concentration of the ER fluid. As only with electrical signal change to the ER-Valve in which ER fluid flowing, ER fluid flow is controlled, so development of simple ER-Valves have been tried. The ER-Valves and pressure drop check method are considered to be applied to the fluid power control system. Using the minかnぉd pressure control valve, a one-link manipulator with FHA in robot system is driven. As a result, it is experimentally confirmed that the pressure control valve using ER fluids is applicable to use in driving actuator. If it applies characteristics of the ER fluids, it will be able to apply in the control system fir the ER Valve which occurs from industrial controller(PLC).

• 대한전기학회논문지:시스템및제어부문D
• /
• 제51권2호
• /
• pp.55-60
• /
• 2002

This paper presents a controller for the multiple DC motors using the CAN(Controller Area Network). The controller has a benefit of reducing the cable connections and making the controller boards compact through the network including expansibility. CAN, among the field buses, is a serial communication methodology which has the physical layer and the data link layer in the ISO's OSI (Open System Interconnect) 7 layered reference model. It provides the user with many powerful features including multi-master functionality and the ability to broadcast / multicast telegrams. When we use a microprocessor chip embedding the CAN function, the system becomes more economical and reliable to react shortly in the data transmission. The controller, we proposed, is composed of two main controllers and a sub controller, which have built with a one-chip microprocessor having CAN function. The sub controller is plugged into the Pentium PC to perform a CAN communication, and connected to the main controllers via the CAN. Main controllers are responsible for controlling two motors respectively. Totally four motors, actuators for the biped robot in our laboratory, are controlled in the experiment. We show that the four motors are controlled properly to actuate the biped robot through the network in real time.

• 로봇학회논문지
• /
• 제9권2호
• /
• pp.124-131
• /
• 2014

The robot mechanisms that were previously researched had only been conducted for the purpose of overcoming the obstacles stably at low speed driving and enhancing the stability against high speed circuitous driving, and yet, the mechanism satisfying two purposes. However, in order to stably drive with high speed on rough terrain, there is a need for satisfying both of these purposes, as well as testing the efficiency of the mechanisms at high speed driving. There, this paper simulated some of the passive mechanisms and focused on checking the performances of passive mechanisms through simulations and analyzing each mechanism on the basis of an evaluation index. The simulation was conducted by Adams (The Multi-body Dynamics Simulation Solution) and used various types of passive mechanisms which were introduced in the robotics field. As a result, the study confirmed that passive mechanisms have a number of situations that affect the driving stability on each direction of roll and pitch. Further study is needed about active mechanism.