• 한국정밀공학회지
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• 제21권1호
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• pp.101-108
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• 2004

An electro-hydraulic manipulator using hydraulic actuators has many nonlinear elements, and its parameter fluctuations are greater than those of an electrically driven manipulator. So it is relatively difficult to obtain stable control performance. In this report, we applied disturbance estimation and compensation type robust control to all axes in a 3-link electro-hydraulic manipulator. From the results of experiment, it was confirmed that the performance of trajectory tracking and attitude regulating is greatly improved by the disturbance observer, which model is the same for each axis. On the other hand, for the autonomous assembly tasks, it is said that compliance control is one of the most available methods. Therefore we proposed compliance control which is based on the position control by disturbance observer for our manipulator system. To realize more stable contact work, the states in the compliance loop are feedback, where not only displacement but also velocity and acceleration are considered. And we applied this compliance control to Peg-in-Hole insertion task and analyzed mechanical relation between peg and hole. Also we proposed new method of shifting the position of end-effector periodically for the purpose of smooth insertion. As a result of using this method, it is experimentally confirmed that Peg-in-Hole insertion task with a clearance of 0.05［mm］can be achieved.

• 드라이브 ㆍ 컨트롤
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• 제12권4호
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• pp.28-34
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• 2015

Because heavy-duty construction vehicles such as excavators are required for good engine-room cooling capacity, a hydraulic gear motor is adopted in the cooling fan drive mechanism to actively control the output speed, instead of adopting the conventional ON/OFF type belt drive. While gear motors are normally limited to 140bars of operating pressure, those for the cooling fan are capable of operating at continuous pressures of up to 220bars. After assembly, all gear motors for high pressure must pass an aging test which is a kind of the wearing process between the gear teeth and motor housing. During the aging process with gradual pressure increments, gear sticking sometimes occurs due to abnormal wear, resulting in defects. This paper focuses on a gear-sticking free aging test controller that is designed together with the knowledge of an experienced operator and the analysis results of experimental data of the gear jamming phenomenon. From the aging experiment, it is demonstrated that the developed controller that can alter the setting pressure of the load pump is effective for stabilizing the abrupt increase in the motor input pressure, thus preventing the hydraulic motor from stopping. This is expected to be helpful for the reduction of defects and increase in productivity.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2007년도 정기학술발표대회 논문집
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• pp.197-204
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• 2007

현재 건설산업 현장에서 나타나는 숙련공 부족 현상, 고령화 문제, 안전상의 문제로 인한 노무 생산성 저하, 임금 상승으로 인한 채산성 악화, 품직 확보의 어려움 및 시공기술 경쟁력의 약화는 국내 건설산업이 해결해야 할 필수적인 당면과제이다. 한편 위험${\cdot}$유해한 작업환경에서 운용되는 토공장비나 매립지에서의 다짐 및 복토공사, 지뢰 및 폭탄 등에 의한 폭발의 위험이 있는 장소에서의 토공작업, 극한지 공사와 같은 환경에서의 공사수요도 점차 늘어가고 있다. 이와 같은 상황에서 토공의 생산성, 품질 및 안전도를 확보하기 위해서는 지능화된 자동화 장비를 이용하여 효율적으로 작업을 수행할 수 있도록 해야 할 필요가 있다. 따라서 본 연구에서는 지능형 굴삭시스템의 개발을 통하여 작업현장의 안전성을 제고하고 품질, 생산성 및 채산성을 향상시키고 선진외국에 비해 보다 진보되고도 경제성 확보가 가능한 건설 자동화 기술의 구현과 기술개발을 통해 국내 건설산업에 있어 새로운 Market Sector의 창출하고자 한다.