Quick picking and heavy lifting are the most common problems in current workplaces. They can cause lumbar muscle damage. The operator then must spend energy, time, and money for recovery or rehabilitation. To solve this problem, we developed a passive-type assistive suit using air mesh material, elastic band, and wire. To determine the strength support effect of the passive-type assistive suit, electromyography (EMG) was performed for eight muscles and the maximum voluntary contraction (MVC) was analyzed when lifting weights of 0%, 15%, and 30% of the subject’s weight in a Semisquat motion. Results showed that MVC increased as the weight of the heavy object increased. However, its increase was not proportional to the decrease in MVC according to the presence or absence of assistive suits or the weight of the heavy object. The highest MVC was observed for the erector spinae muscle under all conditions. The greatest decrease in MVC according to working clothes was measured for the vastus lateralis muscle (lifting: 17.7±2.95%, lowering: 18.3±0.55%). These results show that lifting work performed while wearing a passive-type assistive suit using wires and elastic bands is effective in assisting muscle activity.

There are various micromachining processes available for manufacturing highly integrated and precise parts, each having its own characteristics and limitations. The degree to which micromachining processes meet the requirements depends on characteristics of parts that are different, making it difficult to determine the most appropriate process. In this context, the present study presents an algorithm for determining the optimal micromachining process by applying the Fuzzy AHP-TOPSIS technique frequently used for multi-criteria decision-making. Fuzzy AHP was employed for calculating weights of requirements for a given part. Fuzzy TOPSIS was employed for determining ranks of candidate processes based on weights of requirements and evaluation of processes. Fuzzy logic was applied to handle ambiguous and inaccurate information encountered in evaluating the relative importance of requirements and performances of processes. The case study in which the optimal process for micro-hole drilling of a fuel injection nozzle was determined showed that the proposed method was effective. It could be extended to micromachining of various shapes.

As electrification trends for the automotive industry have accelerated and the demand for high efficiency has increased, hybrid transmissions have been pushed to enlarge the operating range of EOP. And in conventional transmissions, an Idle Stop and Go (ISG) EOP is becoming imperative. The operating conditions of the ISG EOP make it difficult to gain advantages by masking the effects of engine firing or drive noise. Thus, it is necessary to study noise in operating ISG EOPs. Also, the EOP inner components require precise processing and manufacturing because they should be made to a compact size owing to vehicle layout limitations. This paper first describes the results of an experimental study on the abnormal vibration phenomenon, which makes EOP operating noise worse. And secondly it was investigated the cause of abnormal vibration phenomenon which occurs due to processing and manufacturing problems in the process of developing the operating noise of the EOP for ISG on FF type automatic transmission. Finally, the verification results after improvement were described.

An airborne black box should preserve the recorded data under the extreme environmental conditions such an aircraft crash. Through the recorded information from the black box, the cause of the aircraft crash can be analyzed. This requires the black box to safely protect its memory board inside from the external forces or heat generated by the aircraft crash. This paper is a case study conducted to develop the black box to satisfy the crash survival requirements of ED-112A, the standard of performance to develop the black box, and optimize its weight and size. Through the sequential design, analysis, and test process, the black box successfully demonstrated the optimized design, analysis and test subjected to crash survival requirements of ED-112A. The prototype of the black box was fabricated and tested for the verification of each analysis within the requirements of ED-112A.

This paper presents a finite-time tracking control for a robot manipulator in the presence of a modeling uncertainty and an external disturbance. To solve the large chattering phenomenon that is caused by the high switching gain of the slidingmode control, a novel second-order sliding-mode controller that generates a continuous control input is designed with a robust differentiator. The finite-time stability of the closed-loop system is ensured using a constructive Lyapunov-stability analysis. Finally, a numerical simulation of the 2-Axis Pan-Tilt system is performed to verify the effectiveness of the proposed controller.