Kyungmo Jung

Robotic automation system for steel beam assembly in building construction

In building construction, steel beam assembly has been considered as one of the most dangerous manual operations. In this paper, applying robotic technologies to the steel beam assembly task is discussed. Employing the robotic systems to automate such construction tasks gives the following advantages: saving construction time and cost, enhancing operators safety, and improving overall quality. The automated robotic assembly system presented in the paper consists of a robotic bolting device, a robotic mobile mechanism, and a bolting control system including human-machine interface. The robotic bolting device, which includes a bolting end-effector and a robotic manipulator, performs actual bolting operation. Utilizing the robotic mobile mechanism composed of a rail sliding boom mechanism and a scissors-jack type mobile manipulator, the robotic assembly system can be transported to a target position for bolting operation. The bolting control system plays a role of safely and efficiently operating the robotic assembly system employing a hole recognition system based on vision technology and a haptic based HMI (Human-Machine Interface) system. This paper includes the major components of the entire robot system that have been built and the future plans to integrate them.

Development of Automation System for Steel Construction Based on Robotic Crane

This paper deals with an automation system for steel construction based on a robotic crane. Employing an automation system for steel construction of high-rise buildings has following advantages: reducing risk factors in human operation, decreasing the construction cost, and shortening the construction period. The automated robotic crane system suggested in this paper consists of moving mechanism, robot manipulation system, and HMI (human machine interface). Moving mechanism is composed of boom, rail, and scissor-jack type manipulator. Using this mechanism, the robot manipulator can be located anywhere in CF (construction factory). The robot manipulation system is composed of a cabin and two robot arms. The cabin acts as a cockpit for the operator. The first robot arm has a bolting end-effector to assemble H-beams and the second robot arm has an alignment end-effector to align H-beams before assembling task. HMI system helps workers operate robot manipulators through a haptic device and a vision system. Also, it contains ITA (intelligent teaching agent) system that helps unskilled workers operate easily.

Mechanism and analysis of a robotic bolting device for steel beam assembly

Tasks for steel beam assembly in construction field are usually performed by human labors that are exposed to various dangers. This research is about developing a robotic bolting device which assembles TS(Torque-Shear)-type bolt and nut used for steel beam assembly and prevents workers from operating in risky construction environments. The suggested robotic bolting device consists of a bolting end-effector, which actually conducts bolting tasks, and a gantry-type robotic manipulator, which places the bolting end-effector to each bolting position. The bolting process performed by the bolting end-effector, which furnishes two different bolting tools, has two assembly steps to increase the bolting productivity. In the first step, the first-assembly bolting tool assembles the bolt and nut with high speed but low torque, while, in the second step, the second-assembly bolting tool finishes the tightening task with high torque but low speed. Moreover, nut and washer feeder based on robotic manipulation are developed for automatic supply. The two bolting tools equip compliance mechanisms respectively for compensating an angular misalignment between the bolting tool axis and bolt axis which interferes the bolting tool completely grasps the bolt.

Development of the Gripping Control Algorithm for Wire-Suspended Object in Steel Construction

Robot system used in building construction sites can efficiently reduce construction time and increase safety by replacing human in dangerous operations. This paper describes the development of a robotic manipulator control algorithm which provides stable and efficient gripping of a pendulum-like object. The pendulum object mimics the construction materials hanging from tower crane, such as steel beam and column. The robot should be able to handle the heavy objects in order to be used in the building construction sites. This control algorithm requires dynamic modeling of the hanging object. To simplify the analysis, the dynamic modeling was limited to the 2 dimensional pendulum movements in x-y plane. In order to achieve the stable and efficient gripping, a shock isolator is designed using a pre-acting control.

An End-Effector Design for H-beam Alignment in High-Rise Building Construction

There have been active progresses in the construction of high-rise buildings since the robot and information technologies were applied to the construction industry. Although many techniques have been proposed for safe and efficient H-beam lifting and assembly, most of construction tasks are manually operated causing dangerous working environments. The objective of this study is to develop a robotic end-effector for fine H-beam alignment in high-rise building construction. The H-beam has a number of drilled holes so that bolts can go through to assemble the elements. Before the bolts are inserted to combine two H-beams, the bolt holes should be aligned with very tight tolerance. Otherwise, there is a potential for serious damage during the bolting process. In this study, an end-effector design that helps the H-beam alignment for bolting operation is proposed. Moreover, finite element analysis and computer simulations are conducted to evaluate the mechanism.

Experimental evaluation of a robotic bolting device in steel beam assembly

This paper deals with a robotic system for the steel beam assembly task in building construction. Applying the robotic system on the steel beam assembly, we pursue such advantage as improving safety for workers and reducing construction period and cost. The robotic bolting device suggested in this paper has a gantry-type moving apparatus which includes a bolting end-effector. The bolting end-effector is designed especially for bolting mechanism using TS(Torque Shear) type bolt. In order to perform the bolting assembly tests, we made an experimental testbed which was similar to a real steel construction environment. Through the tests, we acquired feasible results for applying the robotic bolting device to real steel construction sites.