홍대희 교수

Climbing robots are robotic systems to move over 2D or complex 3D environments such as walls, ceilings, roofs,and geometric structures and to conduct various tasks. They will not only replace human workers for carrying out risky tasks in hazardous environments, but also increase operational efficiency by eliminating the costly erection of scaffolding and staffing costs. Climbing robots have special characteristics and the ability to adhere to different types of 2D or 3D surfaces, move around, an

3D printing technology, which enables mass production and customized small-volume production, has attracted widespread interest throughout many industries. Applying 3D printing within the construction industry has now been well researched. There are also studies that show research trends related to 3D printing in the construction industry. These studies have mainly referred to equipment, materials, and related software. However, they have discussed only specific fragmentary aspects such as the n

Monitoring and analyzing the operations of construction equipment is critical in the construction engineering and management domain. The ability to detect and classify major activities that construction equipment performs can support a project manager in making proper project-related decisions such as resource allocation and scheduling, resulting in improved productivity. Earth-moving activities as performed by an excavator, which is one of the most frequently used pieces of construction equipme

This paper presents electro-hydraulic servo systems of a robotic excavator with a contour control algorithm. It is very important to precisely move the bucket tip of the excavator to a desired trajectory. There have been many studies to accurately control the bucket dealing with the non-linearity in the hydraulic boom, arm, and bucket cylinders. Beginning with these conventional methods, a new method that focuses on keeping contours rather than just following position commands is presented. In t

Most maintenance works on building exterior walls are carried out by human labor and a cable-driven system (gondola). This approach involves a safety problem, motivating many recent studies of exterior wall automated maintenance methods. However, the conventional studies have been concentrated only on moving mechanism and the studies on cleaning method and processing of cleaning materials are insufficient. In addition, most conventional automated systems are composed of a roll-brush and injectio

The deposit pattern of an evaporating picoliter droplet is studied changing the solvents (water, diethylene glycol, and formamide), mixing composition of the solvents and substrate temperature. When depinning occurs in the early stage of the evaporation period, concentrated solute (or partially deposited solute, if any) also retracts with the receding droplet,resulting in dome shaped deposit patterns. When pinning is maintained during most of the evaporation period, either a ring deposit or a re

As we witnessed in recent major disasters, the functionalities of robots in disaster environments do not appear to meet the high level of expectation from the public. This paper reviews robotic operations in disaster situations and open issues with the current robotic technologies. We particularly address fundamental problems with teleoperated ground robots for disaster response and recovery: design of robot platforms and balance between human supervisory control and robotic anatomy. In attempt

Robot technology is a remarkably interdisciplinary research area, one that can be employed in various industrial fields as well as higher value-added fields. The construction industry, on the other hand, has been known as one of the most difficult research fields to apply robotic schemes. Therefore, applying robot technologies in the construction industry is quite a challenging topic. This paper aims to introduce the progress of automated robotic systems in construction fields, namely with respe

This paper introduces the design of a haptic-based resistance training machine and deals with the details of a control scheme for biceps exercises. The developed training machine has three components: 1) Machine hardware; 2) Impedance control based resistance generator; and 3) User interface. It can enable various resistance trainings considering the biomechanical behavior of individual user. That is, in contrast to conventional exercise machines, it can easily generate two-dimensional exercise

Recently, a robot-based construction automation (RCA) project was finished in Korea, whose purpose was to employ a robotic system instead of human labor in steel beam assembly tasks. In that research, a robotic beam assembly (RBA) system was developed to execute a beam assembly task. A field application using the RBA system at an actual construction site was completed. Because a human operator had to board the cabin and manipulate the system in the air, causing possible safety problems, a teleop

In order to utilize a parallel mechanism as a machine tool component, it is important to estimate the errors of its end-effector due to the uncertainties in parts. This study proposes an error analysis for a new parallel device, a cubic parallel mechanism. For the parallel device, we consider two kinds of errors. One is a static error due to link stiffness and the other is a dynamic error due to clearances in the parts. In this study, we propose a stiffness model for the cubic parallel mechanism

As many high-rise buildings have been dismantled or demolished, researchers have developed many new deconstruction methods and devices. Among these, excavators equipped with attachments such as crushers or breakers have been most widely used on many deconstruction sites. This paper introduces a novel design and control algorithm of haptic devices that can be used to control excavators from a remote site. The newly designed remote control device is well matched with the excavator kinematics, so t

Among the many types of construction equipment, excavators have been widely used due to their versatility in various operations such as digging, crushing, and breaking, etc. In order to achieve more intuitive and intelligent control of the excavator, a new control device has recently been developed to replace the conventional joystick installed in excavators. This paper focuses on a performance evaluation method for this control device in order to determine its feasibility. The fatigue analysis

For successful autonomous valet parking, accurate knowledge of vehicle location in the global map is crucial. Using sensors and maps can be an alternative method for the indoor parking localization to compensate for lack of GPS coverage. However, maps only have static elements such as walls and pillars and semi-static elements such as parked vehicles are not included. Thus, sensor data rarely match with the map data due to the semi-static elements. We developed a robust localization algorithm us

The appropriate operation of a tunnel ventilation system provides drivers passing through the tunnel with comfortable and safe driving conditions. Tunnel ventilation involves maintaining CO pollutant concentration and VI (visibility index) under an adequate level with operating highly energy-consuming facilities such as jet-fans. Therefore, it is significant to have an efficient operating algorithm in aspects of a safe driving environment as well as saving energy. In this research, a reinforceme