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The frequent occurrence of disasters has prompted the development of efficient disaster-responding equipment. This study deals with the design of special-purpose machinery and its performance assessment. We defined scenarios through the environmental analysis of disaster situations and expert consulting. We also formulated a set of design specifications by analyzing the objectives of the tasks that must be performed at disaster sites, based on simulated scenarios and existing disaster response machinery. The disaster-responding special-purpose machinery was designed to perform various tasks and display rapid movement in disaster situations. And this paper presents the control structure configured to operate the developed machinery. The performance of the special-purpose machinery was assessed through different scenario tests.

Jinpoong is a quadruped walking robot developed by the Korea Institute of Industrial Technology. Jinpoong was developed for use in surveillance, reconnaissance, transportation, and guidance tasks in atypical environments such as those encountered after a disaster. To perform these tasks successfully, the robot must be able to walk stably over uneven terrain. The aim of this study was to develop a method for absorbing the impacts experienced by the robot while walking and a method for resisting external forces applied to the side (sagittal plane) of the robot so that it can walk stably. We demonstrate the efficacy of the methods developed through experiments.

An automatic washing machine undergoes rotational unbalance due to unbalanced mass during the spinning process. A liquid balancer is an assembly that plays a role in controlling this unbalance. In recent years, washing machines (drum and automatic types) are becoming larger to handle large laundry items such as comforters. A large-sized washing machine generates a huge centrifugal force in its high speed rotating drum. Thus, a specific vibration reduction technique is required. The design of a liquid balancer has, to date, depended on conventional methods such as experiments and dynamic models. A dynamic model classifies the behavior of liquid inside the balancer into three different patterns, and solutions can be obtained by approximating these patterns as rigid bodies. This method, however, is limited to two-dimensional (2-D) analysis for simple geometry. In the present study, a three dimensional (3-D) computational fluid dynamics (CFD) method is used to analyze flow characteristics inside the liquid balancer for various design parameters. The main parameters include rotational speed, eccentricities of the center of rotation, viscosity of the liquid, gravity orientation, surface tension, and the number of baffles. In particular, the effects of these parameters on the hydraulic force (restoration force) of the liquid balancer are studied.

This paper proposes a method to verify the performance of a redundant 4 degree of freedoms (DOF) hydraulic manipulator when Virtual Spring-damper (VSD) algorithm is applied. It is combined with a control based on the VSD algorithm proposed by Ari-moto et al. To verify the applicability of VSD algorithm to the hydraulic robot manipulator of redundancy 4-DOF, we conducted an experiment to tracking repetitive circle motions of 0.2 m radius to the Y-Z plane in 3.5 seconds. To check the control performance to all directions, the experiment was conducted to the repetitive circle motions which are sloped to 30 ° to the X axis. The effectiveness of the proposed control scheme is demonstrated in experimentation with the 4-DOF manipulator.

The Quadruped walking robot “JINPOONG” is developed to be able to walk in the field which is use to detection, surveillance, reconnaissance, security, and assistance. It can move, carry the luggage of 60kg or more and walk at the uneven terrain such as gravel road and slope of 15 degrees or more. By adjusting the length of the leg caused by the ground reaction force and body posture balance control to the sagittal and lateral plane it is possible to walk stably on the uneven terrain. In this paper, we describe a method for the stable walk on the uneven terrain of JINPOONG and show experimental results about varied terrain.

This paper proposes a method to realize a quick and natural turn, or a change of the walking direction in the middle of locomotion of a biped robot, which takes advantage of a slip between the sole of the foot on the ground and the ground. The turn occurs during a single support phase to shortening the time to turn. Based on the 3D dynamics of a biped model which consists of one particle for a swing foot and a rigid body representing the main body of the robot, the desired trajectory of the swing foot and the expected friction on the ground, the desired ankle motion is computed. Simulations were performed with a 20-DOF biped robot model and the results of the simulations are described.

Purpose : In spite of medical advances, empyema is a serious complication of pneumonia in children. Vaccination practices and antibiotic prescribing practices promote the change of clinical manifestations of empyema and causative organisms. So we made a nationwide clinical observation of 122 cases of empyema in children from 32 hospitals during the 5 year period from September 1999 to August 2004. Methods : Demographic data, and clinical information on the course and management of empyema patients were collected retrospectively from medical records in secondary and tertiary hospitals in Korea. Results : One hundred twenty two patients were enrolled from 35 hospitals. The most frequent age group was 1-3 years, accounting for 48 percent of all cases. The male to female sex ratio was 1.2:1. The main symptoms were cough, fever, respiratory difficulty, lethargy and chest pain in order of frequency. Hematologic findings on admission revealed decreased hemoglobin levels (10.4±1.6 g/dL) and increased leukocyte counts (16,234.3±10,601.8/ L). Pleural fluid obtained from patients showed high leukocyte counts (30,365.8±64,073.0/ L), high protein levels (522.3±1582.3 g/dL), and low glucose levels (88.1±523.5 mg/dL). Findings from pleural fluid cultures were positive in 80 cases(65.6 percent). The most common causative agent was Streptococcus pneumoniae. The majority of patients were treated with antibiotics and closed drainage. Some patients needed open drainage (16.4 percent) or decortication (3.3 percent). The mean duration of hospitalization was 28.6±15.3 days. Conclusion : We analyzed childhood empyema patients during a period of 5 years in Korean children. The most frequent age group was 1-3 years and the most common causative agent was Streptococcus pneumoniaeiae. The majority of patients were treated with antibiotics and close drainage.