Approaches for the Simulation of Deformable Objects in Manufacturing Systems

The validation of control software using methods of Virtual Commissioning (VC), with its origin in the field of machine tools, gains more and more importance in other application areas like process engineering or material-flow-intensive production systems. Especially because of the increasing complexity of technical systems the validation of the control software quality is a major challenge in production technology. To reduce the efforts of modeling and to increase the value of simulation results, a so-called physically model is integrated in the VC. Currently the physically based Virtual Commissioning is restricted to rigid body simulation objects. In this publication new methods for the simulation of deformable objects are shown and validated in an industrial context. Therefore the hybridization of existing simulation methods from computer science using so called physic engines is introduced as a method that simplifies the description of complex simulation objects by adapting well known simulation models. The new approach is comparable to a mixture of a multi body simulation and a real-time finite element simulation

Design of Wreck Removal Considering Safety and Economy

학위논문 (석사)-- 서울대학교 대학원 : 공과대학 조선해양공학과, 2019. 2. 노명일.선박 인양 설계 단계에서 가장 중요한 것은 적절한 인양 방법을 선정하는 것이다. 여기서 적절한 인양 방법이란 안전성과 경제성을 모두 고려한 인양 방법이다. 본 연구에서는 다양한 인양 방법들에 대해 안전성 및 경제성 측면에서 검증 및 평가 방법을 제시하였다. 인양 방법의 안전성을 평가하는 방법으로서 다물체 동역학(Multi-body dynamics)을 적용한 시뮬레이션 프로그램을 활용하였다. 특히, 선박 인양 시 인양 와이어의 접촉과 마찰력을 계산함으로써 기존 방법으로는 할 수 없었던, 침몰 선박을 와이어로 감아서 인양하는 방법에 대한 시뮬레이션을 수행하였다. 이외에도 다양한 외적 영향을 고려하여 동적 인양력을 계산할 수 있도록 하였다. 다음으로 다양한 인양 방법에 대하여 인양 비용을 분석하고 분석결과를 이용하여 경제성 평가 방법을 제안하였다. 선박 인양 시 필요한 비용을 분석하기 위해서 인양 단계별로 필요한 시간을 계산하고 선박 인양 시 사용하는 장비, 인력, 소모품, 자재 등에 대한 비용을 추정하였다. 본 연구에서는 인양 필요 시간 및 비용을 예측하는데 전문가 자문 결과와 물리적 계산을 활용해 정량적으로 추정하고자 노력하였다. 최종적으로 본 연구에서 제안한 안전성 및 경제성 평가 방법을 이용하여 실제 선박의 다양한 인양 방법에 대해 평가를 실시하고 결과를 분석하였다.The most important thing when planning a salvage is choosing a proper lifting method. An appropriate method of lifting is considering safety and economy. In this study, we proposed the evaluation and verification method considering safety and economy. Simulation based on multi-body dynamics is used for assessing the safety of the lifting method. In particular, we implemented a module to calculate the contact and friction force of the wire when lifting the ship, so we can simulate the wire wrapping method. In addition, the dynamic lifting force is calculated by considering various external influences. Next, we propose a method of estimating the salvage cost and economic evaluation is obtained by comparing the results of various lifting methods. To estimate the cost of lifting the ship, the salvage operation is divided into four stages and the required time is calculated. For calculating the cost of lifting, lifting materials are divided into equipment, craft, personnel, and material. In this study, we tried to estimate the time and cost of salvage quantitatively using expert consultation results and calculations. Finally, the safety assessment and economic evaluation method proposed in this study are applied to various lifting methods.1. 개 요 3 1.1. 연구 필요성 3 1.2. 연구 개요 6 1.3. 관련 연구 현황 7 2. 이론 배경 10 2.1. 다물체 운동해석 11 2.2. 와이어의 접촉 및 마찰력 13 2.2.1. 구속조건 기반 와이어 13 2.2.2. 구속조건 기반 와이어의 접촉 14 2.2.3. 와이어의 마찰력 16 2.3. 인양력 계산 22 2.3.1. 중량 23 2.3.2. 부력 24 2.3.3. 외력 26 2.4. 인양 비용 추정 33 2.4.1. 인양 소요 시간 추정 34 2.4.2. 인양 비용 추정 35 3. Test case 37 3.1. 실린더 인양 예제 37 3.2. 소형 선박 인양 예제 40 3.2.1. 인양 개요 40 3.2.2. 시뮬레이션 모델링 41 3.2.3. 시뮬레이션 결과 분석 42 4. 제안방법의 적용 예제 43 4.1. 시뮬레이션 개요 43 4.2. 인양 예제 선정 46 4.2.1. 부력재를 사용한 인양 방법 47 4.2.2. 부력재를 사용하지 않는 인양 방법 49 4.3. 시뮬레이션 결과 53 4.3.1. Case 1 : 부력재 설치, 해상크레인 1대, 와이어 부착 인양 53 4.3.2. Case 2 : 부력재 설치, 해상크레인 1대, 와이어 감기 인양 60 4.3.1. Case 3 : 부력재 미설치, 해상크레인 2대, 와이어 부착 인양 63 4.3.2. Case 4 : 부력재 미설치, 해상크레인 2대, 와이어 감기 인양 67 4.3.3. Case 5 : 잭업바지 2대, 리프팀빔 이용 인양 71 4.4. 안전성 평가 결과 75 4.5. 경제성 평가 결과 77 4.5.1. 총 인양 기간 추정 결과 77 4.5.2. 총 인양 비용 추정 결과 80 4.6. 요약 정리 81 5. 결 론 82 참고문헌 83 6. 부 록 84 6.1. 인양장비 비용 목록 85 6.2. Case 1 인양 비용 계산 결과 90 6.3. Case 2 인양 비용 계산 결과 94 6.4. Case 3 인양 비용 계산 결과 98 6.5. Case 4 인양 비용 계산 결과 101 6.6. Case 5 인양 비용 계산 결과 104Maste

Proceedings of the ECCOMAS Thematic Conference on Multibody Dynamics 2015

This volume contains the full papers accepted for presentation at the ECCOMAS Thematic Conference on Multibody Dynamics 2015 held in the Barcelona School of Industrial Engineering, Universitat Politècnica de Catalunya, on June 29 - July 2, 2015. The ECCOMAS Thematic Conference on Multibody Dynamics is an international meeting held once every two years in a European country. Continuing the very successful series of past conferences that have been organized in Lisbon (2003), Madrid (2005), Milan (2007), Warsaw (2009), Brussels (2011) and Zagreb (2013); this edition will once again serve as a meeting point for the international researchers, scientists and experts from academia, research laboratories and industry working in the area of multibody dynamics. Applications are related to many fields of contemporary engineering, such as vehicle and railway systems, aeronautical and space vehicles, robotic manipulators, mechatronic and autonomous systems, smart structures, biomechanical systems and nanotechnologies. The topics of the conference include, but are not restricted to: ● Formulations and Numerical Methods ● Efficient Methods and Real-Time Applications ● Flexible Multibody Dynamics ● Contact Dynamics and Constraints ● Multiphysics and Coupled Problems ● Control and Optimization ● Software Development and Computer Technology ● Aerospace and Maritime Applications ● Biomechanics ● Railroad Vehicle Dynamics ● Road Vehicle Dynamics ● Robotics ● Benchmark ProblemsPostprint (published version

Characterization and Modelling of Composites, Volume II

Composites have been increasingly used in various structural components in the aerospace, marine, automotive, and wind energy sectors. Composites’ material characterization is a vital part of the product development and production process. Physical, mechanical, and chemical characterization helps developers to further their understanding of products and materials, thus ensuring quality control. Achieving an in-depth understanding and consequent improvement of the general performance of these materials, however, still requires complex material modeling and simulation tools, which are often multiscale and encompass multiphysics. This Special Issue is aimed at soliciting promising, recent developments in composite modeling, simulation, and characterization, in both design and manufacturing areas, including experimental as well as industrial-scale case studies. All submitted manuscripts will undergo a rigorous review and will only be considered for publication if they meet journal standards

Multibody dynamics 2015

This volume contains the full papers accepted for presentation at the ECCOMAS Thematic Conference on Multibody Dynamics 2015 held in the Barcelona School of Industrial Engineering, Universitat Politècnica de Catalunya, on June 29 - July 2, 2015. The ECCOMAS Thematic Conference on Multibody Dynamics is an international meeting held once every two years in a European country. Continuing the very successful series of past conferences that have been organized in Lisbon (2003), Madrid (2005), Milan (2007), Warsaw (2009), Brussels (2011) and Zagreb (2013); this edition will once again serve as a meeting point for the international researchers, scientists and experts from academia, research laboratories and industry working in the area of multibody dynamics. Applications are related to many fields of contemporary engineering, such as vehicle and railway systems, aeronautical and space vehicles, robotic manipulators, mechatronic and autonomous systems, smart structures, biomechanical systems and nanotechnologies. The topics of the conference include, but are not restricted to: Formulations and Numerical Methods, Efficient Methods and Real-Time Applications, Flexible Multibody Dynamics, Contact Dynamics and Constraints, Multiphysics and Coupled Problems, Control and Optimization, Software Development and Computer Technology, Aerospace and Maritime Applications, Biomechanics, Railroad Vehicle Dynamics, Road Vehicle Dynamics, Robotics, Benchmark Problems. The conference is organized by the Department of Mechanical Engineering of the Universitat Politècnica de Catalunya (UPC) in Barcelona. The organizers would like to thank the authors for submitting their contributions, the keynote lecturers for accepting the invitation and for the quality of their talks, the awards and scientific committees for their support to the organization of the conference, and finally the topic organizers for reviewing all extended abstracts and selecting the awards nominees.Postprint (published version

Advances in Vibration Analysis Research

Vibrations are extremely important in all areas of human activities, for all sciences, technologies and industrial applications. Sometimes these Vibrations are useful but other times they are undesirable. In any case, understanding and analysis of vibrations are crucial. This book reports on the state of the art research and development findings on this very broad matter through 22 original and innovative research studies exhibiting various investigation directions. The present book is a result of contributions of experts from international scientific community working in different aspects of vibration analysis. The text is addressed not only to researchers, but also to professional engineers, students and other experts in a variety of disciplines, both academic and industrial seeking to gain a better understanding of what has been done in the field recently, and what kind of open problems are in this area

Hybrid, multiresolution wires with massless frictional contacts

We describe a method for the visual interactivesimulation of wires contacting with rigid multibodies. Thephysical model used is a hybrid combining lumped elementsand massless quasistatic representations. The latter is basedon a kinematic constraint preserving the total length of thewire along a segmented path which can involve multiple bodiessimultaneously and dry frictional contact nodes used for roping,lassoing and fastening. These nodes provide stick and slidefriction along edges of the contacting geometries. The lumpedelement resolution is adapted dynamically based on local stabilitycriteria, becoming coarser as the tension increases, and up to thepurely kinematic representation. Kinematic segments and contactnodes are added and deleted and propagated based on contactgeometries and dry friction configurations. The method givesdramatic increase on both performance and robustness becauseit quickly decimates superfluous nodes without loosing stability,yet adapts to complex configurations with many contacts andhigh curvature, keeping a fixed, large integration time step.Numerical results demonstrating the performance and stabilityof the adaptive multiresolution scheme are presented along withan array of representative simulation examples illustrating theversatility of the frictional contact model