We propose a method for developing an in-pipe inspection robot based on multiple inertial sensors. Estimating the position of underground pipelines where satellite signals do not reach remains challenging. High-precision inertial sensors and high-tech mobile robots can be solutions, but their high price limits their general use. We developed an in-pipe inspection robot by combining various low-cost sensors with a microcomputer-based RC car platform. First, we fabricated a multi-inertial sensors module by combining commercial grade low-cost MEMS inertial sensors. The sensor values measured by the multi-inertial sensor are transmitted to the main computer through the MCU, and the attitude angle of the vehicle is finally calculated through the inverse variance weighted average. The travel distance of the robot is estimated by using hall sensors and neodymium magnets attached to the inside of the wheels. Also, we measured the pipe diameter using multiple ultrasonic sensors. We verified the estimation accuracy of each sensor through experiments and consequently estimated the 3D trajectory of the in-pipe robot.

본 연구에서는 와이어로프의 국부손상 검색을 위해 누설자속기법을 적용하였다. 와이어로프 구조물에 적용하기 위해 리프트오프의 발생을 최소화한 4채널 누설자속 센서헤드를 제작하였고, 이를 사용하여 와이어로프의 국부손상 검색실험을 수행하였다. 국부손상 검색실험을 위해 와이어로프를 준비하였고, 다양한 원주방향을 가지는 부분 단선 손상들을 발생시켰다. 제작된 자속누설 센서헤드를 이용하여 와이어로프 시편의 자속신호를 스캔하였고, 노이즈의 영향을 최소화하고 자속신호의 해상도를 향상시키고자 자속 신호를 미분하여 순간변화량을 손상 검색에 활용하였다. 객관적인 손상 판단을 위해 각 채널에서 계측된 자속신호를 GEV분포를 이용해 설정된 임계값과 비교하였다. 최종적으로 임계값을 초과한 부분의 길이방향 및 원주방향 위치를 실제 손상과 비교함으로써 본 기법의 국부손상 검색 가능성을 살펴보았다.

As domestic buildings have been large-scaled, diversified and high-rise, there have been a consistent demand for design, development of construction technology and accident prevention activity as well as quality enhancement. In spite of governmental and r

The operation and management of a plant require proper accounting for the constraints coming from reliability requirements as well as from budget and resource considerations. Most of the mathematical methods to decide the inspection time interval for plan

국내 고속도로 구조물 점검은 인력위주로 수행중에 있으나, 관리대상 구조물의 급증으로 인력점검의 한계가 발생함에 따라 4차 산업기술(IoT, 드론, AI, 로봇 등)을 활용한 점검로봇 및 점검장비를 개발하여 고속도로 구조물 점검에 활용할 예정이며, 구조물 상태 자동 평가기술을 개발하여 안전점검의 신뢰성 및 효율성을 향상할 예정이다.

Post-tension system was applied most PSC bridges in Korea. Also Grouting was applied to prevent corrosion of the strand. For this reason, it is difficult to inspection the condition of the strand after completion. Therefore, in this paper, the Nondestructive testings(NDTs) developed at domestic and foreign was investigated. In addition, the current level and limit of the NDTs were analyzed considering the existing bridge environment. As a result of the study, Strand condition inspection using NDTs have been analyzed to have technical and environmental limitations.

It is necessary to improve the structure inspection system that integrates various new technologies such as artificial intelligence, big data, and the internet of things, which are core technologies of the 4th industrial revolution in oder to cope with continuously increase in the number of structures and to maintain efficient maintenance against aging.

In this study, the regular inspection check-list for vulnerable areas of debris flow was developed in order to cope with expected debris flow in urban areas. First, items for regular inspection were obtained by the Delphi technique, and the regular inspection check-list was developed based on obtained items. The check-list was verified and improved by means of applying it in 2 test-bed site.

Pumping Station is amended ('15.1.6) a special law (hereinafter siteukbeop) on the safety management of the facility has been incorporated into kinds of facilities. This study aims to introduce siteukbeop drainage pumping stations as part of condition assessment techniques detailed guidelines established for drainage pumping stations being incorporated into the new facility as amended.

By the revision of Special Act on the Safety Control of Public Structures('15 .1.6), coastal structures(breakwaters) was selected as management target. In this study, it is aim to introduce assessment methods for performing precision check-up and precision safety inspection of the coastal structures(breakwaters).

There are a lot of difficulty in present inspection that need many inspectors and much time. It is necessary to improve this inspection working environment. So, we developed an inspection system it can solve problems in current visual inspection and it systemize the inspection tasks scientifically. This is an optimized culvert inspection system which enable to measure a surface condition and sectional shape change. it is used various convergence technology such as 3D laser scanning, digital image processing and texture mapping.

Recently, Advanced automated infrastructure measurements have been made in the Honam high speed railway test-bed. In the future, Real time measurements will be the common based on these technologies. Here, we looked at the domestic and international trends and utilizing the inspection method of Railway Structures using self-powered sensors and wireless network technologies.

The amount of newly-built bridges has been gradually reduced so that the importance of maintenance for existing bridges which has a long services period is issued. Therefore, the maintenance budget for existing bridges is going to be consistently increased. It is needed that a reasonable decision-making methodology for existing bridge maintenance is required to effectively use the limited maintenance budget. In this study, a method of the structural vulnerability evaluation is newly suggested as the one of the evaluation stage for developing a reasonable decision-making methodology.