• 한국기계가공학회지
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• 제18권8호
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• pp.98-103
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• 2019

A more accurate method of feature point extraction and matching for three-dimensional reconstruction using low-resolution images of crops is proposed herein. This method is important in basic computer vision. In addition to three-dimensional reconstruction from exact matching, map-making and camera location information such as simultaneous localization and mapping can be calculated. The results of this study suggest applicable methods for low-resolution images that produce accurate results. This is expected to contribute to a system that measures crop growth condition.

• 한국기계가공학회지
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• 제20권10호
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• pp.80-87
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• 2021

Our study introduces an improved modular agricultural platform to provide convenience to agricultural workers. We upgrade the platform design in three parts, namely, by adding a 458 pattern tire, electricity control, and four-wheel steering function, to improve the platform performance. Results showed that the upgrades enhanced the platform performance and reduced its overall weight as compared with the existing platform. To demonstrate the performance of our improved platform, we conducted five types of experiments with respect to the climbing angle, variable width, attitude control, speed, and obstacle passing.

• 한국기계가공학회지
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• 제20권9호
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• pp.70-75
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• 2021

We developed a platform that was capable of autonomous steering in a furrow environment. It was developed to autonomously control steering by recognizing the furrow using a laser distance, three-axis tilt, and temperature sensor. The performance evaluation indicated that the autonomous steering success rate was 99.17%, and it was possible to climb up to 5° on the slope. The usage time was approximately 40 h, and the maximum speed was 6.7 km/h.

• 한국기계가공학회지
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• 제21권9호
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• pp.92-97
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• 2022

In this paper, as a research on autonomous steering for agriculture, a sensor module for furrow recognition was developed through a low-cost distance sensor combination. The developed sensor module was applied to the vehicle, and when driving in a furrow curve, the autonomous steering success rate was 100% at a curvature of 20 m or more, and 70% at a curvature of 15 m or less. The self-steering success rate according to the ground condition showed a 100% success rate regardless of soil, weeds, or mulching film.

• 한국기계가공학회지
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• 제12권5호
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• pp.1-8
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• 2013

Roll-based, nanoimprint lithography (Roll-NIL) is one effective method to produce large-area nanopatterns continuously. Systems and processes for Roll-NIL have been developed and studied for more than 15 years. Since the shapes of the stamp and the substrate for Roll-NIL can be plates, films, and rolls, there exist many concepts to design and implement roll-NIL systems. Combinations and variations of contact-methods for variously shaped stamps and substrates are analyzed in this paper. The contact-area can be changed by using soft materials such as polydimethylsiloxane (PDMS) or silicone rubber. Ultraviolet (UV) sources appropriate for the roll-to-plate or roll-to-roll process are introduced. Finally, two roll-to-plate nanoimprint lithography systems are illustrated.

• 한국기계가공학회지
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• 제15권6호
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• pp.101-108
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• 2016

This study was initiated to minimize head injuries, which is the largest cause of increased external activity, traffic accident injuries, and death. We developed a low cost airbag that can be covered by a safety helmet based on consumer needs. The results of the survey showed that safety is the most important aspect of consumers' safety helmets. It also predicted that increasing the weight would present the biggest problem. Curved airbag cushion parts that can be attached to a helmet and the sensor part of a block type were designed. Impact analysis was performed by specifying the pressure inside the airbag and the volume of the airbag as variables.

• 한국융합학회논문지
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• 제12권1호
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• pp.185-191
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• 2021

과립 분말 야금법은 기존 분말 야금법보다 치밀도가 높은 소결 부품을 얻을 수 있는 제조 기술이다. 하지만 추가 과립화 공정에 따른 생산 비용 증가가 상당하다는 단점이 있다. 과립 분말 야금법의 생산성 향상을 위해서는 과립 분말 제조 시 높은 회수율이 보장되어야 한다. 본 논문에서는 분체 동역학 전산 해석법인 이산요소법을 이용하여 과립 분말의 수율에 영향을 미치는 과립화 공정의 특성에 대해 살펴보았다. 분무 과립 공정 중 과립화 분말의 비산, 충돌 및 소착 현상을 시뮬레이션함으로써 분무 건조기의 운전 조건에 따른 과립화 분말의 파손 및 회수 가능 여부를 예측하였다. 본 논문의 가상 공정 시뮬레이션 융합 연구 결과는 실제 금속 분말의 분무 과립화 공정의 생산성 향상에 이바지할 것으로 기대한다.

• 한국산업융합학회 논문집
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• 제22권5호
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• pp.583-589
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• 2019

One of the core pillars of the Fourth Industrial Revolution is the innovation of the manufacturing industry. From the beginning, the 4th Industrial Revolution appeared in Germany under the concept of 'Industrial 4.0', which means a radical change in the manufacturing industry that can provide super intelligent product production and services based on artificial intelligence and big data. Since manufacturing innovation is a change in the industrial character of the entire nation, the initial role of government is important. Korea also has various policies related to the 4th Industrial Revolution, but there are still various problems to be solved. Therefore, this paper monitors and analyzes the public R&D projects of the advanced countries on manufacturing innovations in the background mentioned above, and through this, the policy implications are drawn.

• 한국기계가공학회지
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• 제19권8호
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• pp.94-103
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• 2020

This study investigated the effects of ultrasonic nanocrystal surface modification (UNSM) on the deteriorated surface of AISI SUS316L additively manufactured (AM) using the powder bed fusion (PBF) technique. Specifically, the effects of UNSM conditions on surface topology, hardness, and anti-corrosion were examined. Before UNSM treatment, the stainless steel 316L powder was processed via the PBF machine to prepare a substrate. We observed surface changes due to UNSM treatments in PBF SUS316L substrates and examined the correlation between topology changes, roughness, hardness, and anti-corrosion. After UNSM treatment, the coarse as-built surface was refined, and a regular micro-profile was implemented. Compared to the non-treated PBF sample, the waviness and roughness of the surfaces after UNSM treatment decreased by up to 56.0% and 94.5%, respectively, and decreased further as the interval decreased. The hardness improved by up to 63.0% at a maximum depth of 500 ㎛ from top surface by the UNSM treatment. The results of the corrosion test showed that the corrosion resistance of the UNSM specimens was moderately improved compared to that of the untreated surface. This study confirmed that UNSM is an effective post-processing technique for additively manufactured parts.

• 디지털융복합연구
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• 제14권3호
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• pp.219-226
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• 2016

본 연구에서는 유럽의 제조업 혁신의 발원지인 독일의 제조업 혁신 추진 전략을 살펴봄으로써 한국이 추진하고 있는 제조업 3.0을 성공적으로 추진하기 위한 전략적 함의를 제시하고자 한다. 현재 한국 경제의 잠재성장력은 점점 약화되어 왔으며, 신흥국과의 기술격차가 점차 감소되고 있어, 국가 경제의 경쟁력 제고를 위한 국가적인 노력이 필요한 상황이다. 신흥국의 성장은 제조업의 수출수요를 유발하여 새로운 기회 요인이 되고 있지만, 시장점유율을 놓고 후발개도국과 치열한 경쟁을 벌여야 하는 한국에게는 위협요인이기도 하다. 유사하게 유럽의 장기적인 경기침체와 신흥국의 부상에도 불구하고 여전히 높은 수준의 산업경쟁력을 유지하고 있는 독일은 바로 이러한 점에서 국내 제조업 발전 정책의 추진 및 개선에 시사점을 제공해 줄 것으로 사료된다.