• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.47 no.6
• /
• pp.40-46
• /
• 2010

It is an important element increasing ship production to manage an accurate position of transporters(TP) and ship blocks in a shipyard. However, most works are presently being performed by judgment of a system manager and skilled workers. This paper introduced about the system for tracking an accurate position of the transporters and the blocks which are main mobile objects in the shipyard, and proposed a method to decide whether or not a loading/unloading state of the blocks, which is one of the most important functions of the tracking system. Three sensors were used in order to implement the method. One is a RFID reader to identify a target block, another is a RFID reader to estimate a position of the TP as it recognizes a underground tag. The other is a ultrasonic sensor to detect an object. Two experiments were carried out in the shipyard. After correcting errors found on the first experiment. we confirmed that the result could be applied to the shipbuilding yard from the final experiment.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.4
• /
• pp.759-764
• /
• 2011

This paper deals with the method of using the amended virtual force field technique to avoidance the front environment(wall, obstacles etc.) in navigating by using the environmental informations recognized by a ultrasonic-ring and pan/tilt CCD camera equipped on a mobile robot. we will give an explanation for the robot system architecture designed and implemented in this study and a short review of existing techniques, since there exist several recent thorough books and review paper on this paper. It is proposed the rusult from the experimental run based on a virtual force field(VFF) method to support the validity of the aforementioned architecture of mobile service robot for local navigation and obstacle avoidance for autonomous mobile robots. We will conclude by discussing some possible future extensions of the project. The results show that the proposed algorithm is apt to identify obstacles in an indoor environments to guide the robot to the goal location safely.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.4
• /
• pp.940-947
• /
• 2015

This paper presents the region of interest pattern image extraction method on a display printed matrix pattern. Proposed method can not use conventional method such as laser, ultrasonic waves and touch sensor. It searches feature point and rotation angle using luminance and pattern reliable feature points of input image, and then it extracts region of interest. In order to extract region of interest, we simulate proposed method using pattern image written various angles on display panel. The proposed method makes progress using the OpenCV and the window program, and was designed using Verilog-HDL and was verified through the FPGA Board(xc6vlx760) of Xilinx.

• Transactions of the Korean Society of Pressure Vessels and Piping
• /
• v.12 no.1
• /
• pp.93-100
• /
• 2016

Since the sodium-cooled fast reactor is operated in a hostile environment due to the use of liquid sodium as its coolant, advanced techniques for in-service inspection are required to periodically verify the integrity of the reactor. This paper presents the development of in-service inspection techniques for Proto-type Generation IV Sodium-cooled Fast Reactor. First, the 10 m long plate-type ultrasonic waveguide sensor has been developed for in-service inspection of reactor internals, and its feasibility was verified through several under-water and under-sodium experiments. Second, the combined inspection system for in-service inspection of ferromagnetic steam generator tubes has been developed. The remote field eddy current testing and magnetic flux leakage testing can be conducted simultaneously by using the developed inspection system, and the detectability was demonstrated through several damage detection experiments. Finally, the electro-magnetic acoustic transducer which can withstand high temperature and be installable in the remote operated vehicle has been developed for in-service inspection of the reactor vessel, and its detectability was investigated through damage detection experiments.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.13 no.2
• /
• pp.186-191
• /
• 2003

Skills in tracing of the MR divide into following, approaching, avoiding and warning and so on. It is difficult to have all these skills learned as neural network. To make this up for, skills consisted of each module, and Mobile Robot was controlled by the output of module adequate for the situation. A mobile Robot was equipped multi-ultrasonic sensor and a USB Camera, which can be in place of human sense, and the measured environment information data is learned through Modular Neural Network. MNN consisted of optimal combination of activation function in the Expert Network and its structure seemed to improve learning time and errors. The Gating Network(GN) used to control output values of the MNN by switching for angle and speed of the robot. In the paper, EN of Modular Neural network was designed optimal combination. Traveling with a real MR was performed repeatedly to verity the usefulness of the MNN which was proposed in this paper. The robot was properly controlled and driven by the result value and the experimental is rewarded with good fruits.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.19 no.6
• /
• pp.47-55
• /
• 2019

The robot is the creation of new markets and various cooperation according to the manufacturing paradigm shift. Cooperative management easy for existing industrial robots, robots work on productivity, manpower to replace the robot in every industry cooperation for the purpose of and demand increases.to exist But the industrial robot at the scene of the cooperation working due to accidents are frequent, threatening the safety of the operator. Of industrial site is configured with a robot in an environment ensuring the safety of the operator to and confidence to communicate that can do the possibility of action.Robot guard system of the need for development cooperation. The robot's cooperation through the sensors and computer vision task within a radius of the double to prevent accidents and accidents should reduce the risk. International protocol for a variety of industrial production equipment and communications opc ua system based on ultrasonic sensors and cnn to (Convolution Neural Network) for video analytics. We suggest the cooperation with the robot guard system. Robots in a proposed system is unsafe situation of workers evaluating the possibility of control.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.41 no.5
• /
• pp.401-407
• /
• 2017

This paper describes wavenumber filtering for damage detection using single-frequency standing wave excitation and laser scanning sensing. An embedded piezoelectric sensor generates ultrasonic standing waves, and the responses are measured using a laser Doppler vibrometer and mirror tilting device. After scanning, newly developed damage detection techniques based on wavenumber filtering are applied to the full standing wave field. To demonstrate the performance of the proposed techniques, several experiments were performed on composite plates with delamination and aluminum plates with corrosion damage. The results demonstrated that the developed techniques could be applied to various structures to localize the damage, with the potential to improve the damage detection capability at a high interrogation speed.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.13 no.4
• /
• pp.25-31
• /
• 1994

A system for EMAT, which generates ultrasound by electro-magnectic forces and performs nondestructive testing in noncontact, was established. By linking it with a 3 axis scanning system and a data acquisition and processing system the automation of EMAT testing was attempted. A EMAT sensor was fabricated and the directivity pattern of it was measured. To be suitable automation, it has a transmitter and a receiver in one case and the main beam direction of it can be controlled by the frequency of driving signal. A program which controls the EMAT system, the 3 axis scanner and the data acquisition and processing system was developed. It also processes acquired data and displays the processing results. IBM-PC/AT compatible PC was used as main controller and the stratage of the program is emulation of real devices on the PC monitor. To provide the performance of the established EMAT system, two aluminium blocks containing artificial flaws and a welded aluminium block were tested. The result of the tests were satisfactory.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2005.11a
• /
• pp.169-170
• /
• 2005

본 연구에서는 초음파 센서에 응용 가능한 $0.4Pb(Ni_{1/3}Nb_{2/3})O_3-0.6Pb(Zr_xTi_{1-x})O_3+0.5Wt%$ $MnO_2$ 세라믹스에 Zr/(Ti+Zr)비를 0.37에서 0.41로 변화시킨 조성을 1175 $\sim$ 1200$^{\circ}C$ 온도에서 소결하여 이의 결정구조 및 미세조직을 분석하였고, 압전, 유전 특성을 고찰하였다. 본조성에서 x=0.385 조성에서 최대 유전상수 값 3490 이 나타났으며, 그 이상의 첨가에서는 감소하였다. 상경계 영역인 x=0.385 조성에서 $\varepsilon$r, $K_p$, $d_{33}$ 값이 최대값을 나타내었다. $0.4Pb(Ni_{1/3}Nb_{2/3})O_3-0.6Pb(Zr_xTi_{1-x})O_3+0.5Wt%$ $MnO_2$, 세라믹스에서는 kp 와 $d_{33}$ 는 Zr/(Ti+Zr)비 0.385조성까지 증가하였다가 그 이상 조성에서 감소하였다. $1175^{\circ}C$에서 2시간 소결한 x=0.385조성에서 $\varepsilon$r=3490, kp=0.71, Qm=476의 우수한 압전 특성을 나타내었다.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.19 no.4
• /
• pp.451-456
• /
• 2009

In this paper, a virtual force is generated and fed back to the operator to make the teleoperation more reliable, which reflects the relationship between a slave robot and an uncertain remote environment as a form of an impedance. In general, for the teleoperation, the teleoperated mobile robot takes pictures of the remote environment and sends the visual information back to the operator over the Internet. Because of the limitations of communication bandwidth and narrow view-angles of camera, it is not possible to watch certain regions, for examples, the shadow and curved areas. To overcome this problem, a virtual force is generated according to both the distance between the obstacle and the robot and the approaching velocity of the obstacle w.r.t the collision vector based on the ultrasonic sensor data. This virtual force is transferred back to the master (two degrees of freedom joystick) over the Internet to enable a human operator to estimate the position of obstacle at the remote site. By holding this master, in spite of limited visual information, the operator can feel the spatial sense against the remote environment. It is demonstrated by experiments that this collision vector based haptic reflection improves the performance of teleoperated mobile robot significantly.