• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.7 no.6
• /
• pp.141-148
• /
• 1998

A loader is construction & road or agricultural machinery for lifting, moving, and mixing. This study deals with the agricultural mini loader for stock raising farming. The performance of the machine is established by pulling power, working lifting capacity, and minimum circling radius, etc. Also, driving easiness and endurance are very important in manufacturing. Thus, this study has developed the loader with the 4-wheel driving equipment by gear transmission, the 4-wheel steering equipment by power handle steering type, and the equipment making four wheels touch simultaneously on the rugged ground. The developed loader having these functions was very fit in a small cattle shed or a rugged ground. This study is divided into two parts; (I) development of 4WS transmission and (II) construction of the loader by 4WS system and other equipments.

• Journal of Biosystems Engineering
• /
• v.26 no.3
• /
• pp.237-244
• /
• 2001

This work was intended to investigate the effect of vibration transmission paths on the ride vibration of tractor during the rotavating and transporting operations by applying the vibration path analysis method. Accelerations at the cab mounts were measured during the rotavating and transporting operations. Ride vibrations at the sear were than calculated using the measured accelerations at the cab mounts, and the frequency response functions and inertances between the seat and cab mounts, which were derived experimentally by the impact hammer test in static condition. The human sensitivity to vibration frequency was also taken into consideration for the calculation of ride vibrations at the 1/3 octave center frequencies in the frequency domain. Vibrations transmitted through rear cab mounts affected more significantly the ride vibration of tractor. The peak accelerations at the seat occurred at the frequencies of the engine and crank speed, and the frequency induced by tire lugs on the road transportation. It was found that the rear cab mounts should be improved in order to reduce the ride vibrations more effectively.

• Journal of Biosystems Engineering
• /
• v.23 no.4
• /
• pp.327-334
• /
• 1998

This work was intended to determine the optimum values of the cab suspension parameters by a simulation method in order to minimize the seat accelerations of agricultural tractors in the frequencies lower than 50Hz. A dynamic model of cab motions was developed and verified using a tractor excited over half-sine bumps on a concrete test road. A simulation program based on the model was also developed. A method was proposed to determine the optimum values of the suspension parameters. It was found that the natural frequencies of the cab and seat suspensions must be apart as far as possible until the sum of seat and cab accelerations is minimized, which also reduces the seat accelerations maximally.

• Journal of Biosystems Engineering
• /
• v.9 no.1
• /
• pp.1-4
• /
• 1984

노외차량(路外車輛)의 승차(乘車) 시뮬레이션을 위한 착석(着席) 상태(狀態)의 운전자(運轉者) 모델을 개발(開發)하였다. 운전자(運轉者) 모델은 머리, 몸체, 신부(腎部)로 크게 나누어 자유도(自由度) 3의 진동체로 가정(假定)하고 머리와 몸체, 몸체와 신부(腎部)는 각각 목과 장기(臟器)를 나타내는 탄성체로서 연결하였다. 또한 인체의 해부학적(解部學的) 구조(構造)와 일치(一致)하도록 머리와 신부(腎部)사이에는 척추(脊椎) 부분(部分)을 포함시켰다. 모델의 각 변수(變數)들은 기존(旣存)의 실험(實驗) 결과(結果)를 이용(利用)하여 머리부의 진동(振動)이 실험(實驗) 결과(結果)와 일치(一致)하도록 시뮬레이션 방법(方法)으로 결정(決定)하였다.

• Transactions of The Korea Fluid Power Systems Society
• /
• v.4 no.4
• /
• pp.21-27
• /
• 2007

A hydraulic breaker for construction machinery generally used for the destroying and disassembling of buildings, crashing road pavement, breaking rocks at quarry and so on. So the measurement of the impact energy of a hydraulic breaker is very important thing to prove its capability to manufacturers and customers. Therefore the prediction of impact energy in design process is very helpful to the most of breaker manufacturers. In this study, we carried on modeling and simulation of a hydraulic breaker to predict impact energy via commercial CAE software. The modeling and simulation of a hydraulic breaker was achieved with two parts. One is a hydraulic circuit analysis part via AMESim and the other is impact strain analysis part via ANSYS.

• 연구논문집
• /
• s.32
• /
• pp.45-53
• /
• 2002

Hydraulic breaker attached excavator generally used for the destroying and disassembling of buildings, crashing road pavement, breaking rocks at quarry and etc. The developed breaker are determined their own destructive force and number of impact by the input hydraulic flow rate and pressure than the operating conditions, In this study, the characteristics of pressure variation in closed vessel is invested for testing the impact energy of hydraulic breaker. To test the impact energy, the test system is designed as a mechanism consisted with a hydraulic cylinder, main base, pressure sensor, LVDT, data acquisition system and etc.. The developed test system is applied to measure the impact energy for hydraulic breaker. The proposed testing method could be applied for conventional impact test and the control system evaluation for hydraulic breakers.

• Journal of Biosystems Engineering
• /
• v.25 no.5
• /
• pp.359-368
• /
• 2000

In this paper, mathematical model was developed for predicting the tractive performance of off-road wheeled vehicles operated on soft terrains. Based on the mathematical model, a computer simulation program(TPPMWV) was developed. The model takes into account main design parameters of wheeled vehicle, including radius and width of front and rear tire, weight of vehicle, wheelbase and driving type(4WD, 2WD). Soil characteristics, such as the peressure-sinkage and shearing characteristics and the response to repetitive loading and slip-sinkage effect, are also taken into consideration. The effectiveness of the developed model was verified by comparing the predicted drawbar pulls using TPPMWV with measured ones obtained by field tests for two different driving types of wheeled vehicle. As a results, the drawbar pulls predicted by the TPPMWV were well matched to the measured ones within the absolute errors of 3.916%(4WD) and 13.31%(2WD) for two different driving types, respectively.

• Journal of Drive and Control
• /
• v.16 no.1
• /
• pp.22-28
• /
• 2019

This paper develops ABS braking real - time simulator to develop vehicle braking system by simulation. Recently, real-time simulation is widely used in the development of vehicles to decrease development time. In the field of electronic braking, real-time simulation is actively underway. In order to simulate electronic braking model in real time, a vehicle model, a hydraulic model, and a control S/W model are required. These models must be calculated in one platform. Therefore, in this paper, a vehicle model composed of CarSim and a hydraulic model composed of SimulationX using S/W in actual ABS controller was developed as a Simulink model base and linked with Matlab real time model. Using this real-time model, design effects of the electronic braking controller were simulated according to road surface condition to verify its operability.

• International Journal of Advanced Culture Technology
• /
• v.7 no.2
• /
• pp.218-226
• /
• 2019

In modern society, people live in an environment with artificial or natural noise. Especially, the sound that corresponds to the artificial noise makes the noise itself and affects each other because many people live and work in the city. Sounds are generated by the activities and causes of various people, such as construction sites, aircraft, production machinery, or road traffic. These sounds are essential elements in human life and are recognized and judged by human auditory organs. Noise is a sound that you do not want to hear by subjective evaluation, and it is a loud sound that gives hearing damage or a sound that causes physical and mental harm. In this study, we introduce the method of stimulating the human hearing by finger vibration and explain the advantages of the proposed method in various kinds of a noise environment. And how to improve the sound quality to improve efficiency. In this paper, we propose a method to prevent the loss of hearing loss and the transmission of sound information based on proper signal to noise ratio when using portable IT equipment in various noise environments.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2020.06a
• /
• pp.171-172
• /
• 2020

Recently, the need for smart construction technologies related to the Fourth Industrial Revolution has been increasing in order to improve productivity of the construction industry. The Ministry of Land, Infrastructure and Transport has established Smart construction technology road map to commercialize the smart construction, and research and development is also underway. However, due to the lack of cost estimation standards for such smart construction technologies to be deployed to actual sites, smart construction technologies are not actively applied to construction sites. In particular, cost estimation standards are needed for construction machinery equipment with ICT technology that is currently available for commercialization. Therefore, as a preliminary study for the development of smart construction cost estimation standards, a case study was conducted on ICT construction estimation standards in Japan and present them as basic data for standards in Korea.