Journal articles: 'Coupling with floating object'

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Huang, Panfeng, Yangsheng Xu, and Bin Liang. "Dynamic Balance Control of Multi-Arm Free-Floating Space Robots." International Journal of Advanced Robotic Systems 2, no. 2 (June 1, 2005): 13. http://dx.doi.org/10.5772/5797.

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This paper investigates the problem of the dynamic balance control of multi-arm free-floating space robot during capturing an active object in close proximity. The position and orientation of space base will be affected during the operation of space manipulator because of the dynamics coupling between the manipulator and space base. This dynamics coupling is unique characteristics of space robot system. Such a disturbance will produce a serious impact between the manipulator hand and the object. To ensure reliable and precise operation, we propose to develop a space robot system consisting of two arms, with one arm (mission arm) for accomplishing the capture mission, and the other one (balance arm) compensating for the disturbance of the base. We present the coordinated control concept for balance of the attitude of the base using the balance arm. The mission arm can move along the given trajectory to approach and capture the target with no considering the disturbance from the coupling of the base. We establish a relationship between the motion of two arm that can realize the zeros reaction to the base. The simulation studies verified the validity and efficiency of the proposed control method.

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Lai, Bin Bin, Cheng Bi Zhao, Xiao Ming Chen, You Hong Tang, and Wei Lin. "A Novel Structural Form of Semi-Submersible Platform for a Floating Offshore Wind Turbine with Hydrodynamic Performance Analysis." Applied Mechanics and Materials 477-478 (December 2013): 109–13. http://dx.doi.org/10.4028/www.scientific.net/amm.477-478.109.

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With the mature of floating offshore wind turbine technology, floating wind farm building in the deep sea becomes an inevitable trend. In the design of floating offshore wind turbine, the change of structural form is the main factor influencing hydrodynamic performance. This research, taking a typical sea condition in China's coastal areas as the object of study, designs a novel semi-submersible foundation for NREL 5 MW offshore wind turbine in 200 m deep water. In the design, deep-draft buoys structures are used to reduce the force of waves on the floating offshore, while damping structures are used to optimize the stability of wind turbine and reduce the heave amplitude. By means of numerical simulation method, the hydrodynamic performance of semi-submersible support is studied. Meanwhile, the response amplitude operators (RAOs) and the wave response motions of platform are calculated. The results in time domain indicate that the floating wind turbine system can keep safe and survive in the harsh sea condition, coupling wind, waves and currents. It is showed that the designed semi-submersible support of platform has excellent hydrodynamic performance. This change of structural form may serve as a reference on the development of offshore wind floating platform.

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Suo, Chunguang, Mingxing He, Guoqiong Zhou, Xinghua Shi, Xiangyu Tan, and Wenbin Zhang. "Research on Non-Invasive Floating Ground Voltage Measurement and Calibration Method." Electronics 12, no. 8 (April 14, 2023): 1858. http://dx.doi.org/10.3390/electronics12081858.

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Voltage measurement is an important part of power system operation, and non-intrusive voltage sensors have the advantages of low insulation difficulty, simple structure, easy loading and unloading, and high construction safety, which have become a new direction for voltage measurement. Based on the principle of electric field coupling, this paper constructs a non-intrusive floating ground three-capacitance voltage measurement model, which can complete the accurate measurement of voltage without connecting with the line to be measured and the earth in the measurement process. In non-intrusive voltage measurement, the change of the object to be measured or the measurement environment will cause the change of the coupling capacitance, which leads to the uncertainty of the transmission relationship of the sensor and the large error of measurement results. In order to solve this problem, a new method of sensor calibration is proposed in this paper. By sampling capacitance in parallel between two electrodes of the sensor, changing the capacitance value, and establishing an input output equation, the coupling capacitance value and the voltage value to be measured under different operating conditions are solved. In addition, the sampling capacitance is often several orders of magnitude larger than the sensor’s own capacitance, making the sensor’s voltage division ratio significantly higher and more conducive to the measurement of high voltages. The experimental results show that the measurement error is less than 2%, which verifies the feasibility of the method and the accuracy of the voltage measurement.

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Xue, Xiangzhen, Jian Liu, Jipeng Jia, Siwei Yang, and Yifan Li. "Simulation and Verification of Involute Spline Tooth Surface Wear before and after Carburizing Based on Energy Dissipation Method." Machines 11, no. 1 (January 8, 2023): 78. http://dx.doi.org/10.3390/machines11010078.

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This work studies the tooth surface wear of floating involute spline couplings. Based on the energy dissipation method, this study takes the floating involute spline couplings as the research object, divides the whole wear cycle into three wear stages and analyzes its wear mechanism, and proposes a wear prediction model suitable for floating involute spline couplings. By using Abaqus, the simulation of the involute spline couplings before and after carburizing was carried out when the floating distance was 0 mm, 0.3 mm and 0.6 mm, respectively. The wear depth of each tooth was compared and analyzed, and the axial and radial distributions of the wear on the tooth surface of the involute spline couplings were explored. Finally, the floating involute spline couplings test bench was used to verify the spline wear before and after carburizing. The results show that with the increase in floating distance, the wear of the tooth surface also increases, and the upper edge of the tooth surface is seriously worn. Through the comparative analysis of the spline tooth surface wear before and after carburizing treatment, it can be seen that carburizing treatment can effectively reduce the wear degree of the spline couplings tooth surface and improve the service life of the spline couplings, but at a high floating distance, carburizing treatment has no significant effect on improving the performance of the tooth surface.

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Du, Nei Juan, Yue Guo Shen, and Jun Hai Zhang. "The Dynamic Response Analysis of the Multi-Body System with Floating Base Based on the ADAMS." Applied Mechanics and Materials 574 (July 2014): 58–61. http://dx.doi.org/10.4028/www.scientific.net/amm.574.58.

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The dynamic response analysis of the multi-body system with floating base includes the interaction between bodies and flow field as well as the one inside the multi-body system, which needs to use both the time-domain theory about the interaction between the object and the flow field and the method of multi-body system dynamics. With the growing complexity of the upper body, the multi-body system with floating base, whose generalized modeling and analysis become an inevitable trend.Using ADAMS(Automatic Dynamic Analysis of Mechanical System) for multi-body system dynamics analysis has unique advantages. It integrates modeling, solving and visualization technology. It also can realize automatically statics, kinematics and dynamics analysis. In this paper, the feasibility of ADAMS software and some related key issues are discussed, including the system architecture, fluid force analysis, fluid-structure coupling calculation module and ADAMS multi-body dynamics analysis module of data generation and transmission, etc.

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Chang, Zongyu, Yang Zhang, Zhongqiang Zheng, Lin Zhao, and Kunfan Shen. "Dynamics Simulation of Grasping Process of Underwater Vehicle-Manipulator System." Journal of Marine Science and Engineering 9, no. 10 (October 15, 2021): 1131. http://dx.doi.org/10.3390/jmse9101131.

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Underwater vehicle-manipulator system (UVMS) can be applied to fulfill different complex underwater tasks such as grasping, drilling, sampling, etc. It is widely used in the field of oceanographic research, marine exploration, military, and commercial applications. In this paper, the dynamic simulation of UVMS is presented in the process of grasping an object. First, the dynamic model of UVMS, which considers the change of the load of manipulator when the end effector of manipulator grasps the object, is developed. To compare different conditions, numerical simulation of grasping processes without/with vehicle attitude control are carried out. The simulation results show that the coupling dynamics between the vehicle and the manipulator in the grasping process are clearly illustrated. It deteriorates the positioning accuracy of the end effector of the manipulator and is harmful to underwater precision operations. The tracking position error of end effector without vehicle control is large and UVMS cannot complete the grasping task under this condition. Vehicle control can compensate the motion of the vehicle due to the coupling effect caused by the motion of the manipulator. This study will contribute to underwater operation mission for UVMS with floating base.

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Ji, Hong, Jie Guo, Gao Zhang, Ke Yang, Juncheng Jiang, Yaxin Wang, Zhixiang Xing, and Haipu Bi. "Multi-Factor Coupling Analysis of Porous Leakage in Underwater Gas Pipelines." Processes 11, no. 4 (April 19, 2023): 1259. http://dx.doi.org/10.3390/pr11041259.

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Natural gas pipeline leaks under the sea will have a significant negative effect on the marine ecosystem, result in significant financial losses, and possibly even harm marine floating objects. The VOF (Volume of Fluid) multi-phase flow model is used to numerically simulate and study the diffusion process of porous leakage in submarine gas pipelines. Experiments confirmed the model’s correctness and dependability. Based on this, the coupling effect and the porous effect of the leakage velocity, the size of the leaked pore, and water velocity of the natural gas pipelines on the diffusion of porous leakage in the submarine gas pipelines are analyzed with the test scheme designed by the orthogonal test method. The similarity principle is used to connect the leakage model with the actual application. The results show that three factors, namely, the leakage velocity, the size of leaked pore, and the water velocity, influence the shape of the air mass, the time when the gas reaches the sea surface, and the diffusion range. The size of the leakage hole and the leakage velocity have a substantial impact on the form of the air mass and the amount of time it takes for the gas to reach the sea surface, while the water velocity has no effect. Additionally, while there is essentially little impact from the leakage velocity, the size of the leaky pore and the water velocity have a significant impact on the diffusion range. Furthermore, the porous effect between leaky pores has a significant impact on the gas diffusion range. This study can serve as a guide for risk assessment and emergency decision-making regarding a submarine gas pipeline leak.

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Zhang, Qingyun, and Xinhua Zhao. "Inverse Dynamics Modeling and Simulation Analysis of Multi-Flexible-Body Spatial Parallel Manipulators." Electronics 12, no. 9 (April 28, 2023): 2038. http://dx.doi.org/10.3390/electronics12092038.

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Taking a spatial parallel robot with flexible joints and links as the research object, a dynamic modeling method for a multi-flexible-body robot system is proposed. Its effectiveness is verified by comparing the numerical model with a simulation model. (1) Background: The elastic deformation of the flexible joints and links in the multi-flexible-body spatial parallel robot under high-speed operation and the coupling effect between the flexible and the rigid components substantially affect the system stability and trajectory accuracy. Therefore, it is necessary to analyze the dynamic characteristics of multi-flexible-body robot systems by establishing accurate dynamic models. (2) Methods: First, the finite element method was used to discretize the flexible joints and links. Subsequently, according to the floating frame of the reference coordinate method, the deformation coordinates of the flexible joints and links were described. The first six modal information were retained to develop a dynamic model considering the coupling effect between the flexible joint and rigid link and between the flexible joint and link. Second, a dynamic model of the end-effector with small displacement changes was established according to the coordination matrix. Furthermore, a dynamic model of rigid links was established based on the vector method and combined with the higher-order dynamic model of flexible joints and links to form the dynamic model of multi-flexible-body kinematic chains. Finally, the dynamic model of the three kinematic chains was assembled with that of the end-effector to obtain an accurate dynamic model of the multi-flexible-body robot systems. (3) Results: The motion trajectory of the multi-flexible-body robot floats around the fully rigid spatial parallel robot in a certain range. Its range of travel in the x, y, and z directions was 0 to 3.14, 0 to 4.06, and 0 to 0.483 mm, respectively. With increasing angular velocity, the maximum absolute amplitude of the driving torque of each branch chain also increases, whereas its motion trend remains unchanged. (4) Conclusions: The proposed dynamic modeling method and its simulation model for multi-flexible-body robots are correct, which can lay a solid foundation for further control performance analysis.

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Rodríguez-Barrera, M. I., Ch Helling, and K. Wood. "Environmental effects on the ionisation of brown dwarf atmospheres." Astronomy & Astrophysics 618 (October 2018): A107. http://dx.doi.org/10.1051/0004-6361/201832685.

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Context. Brown dwarfs emit bursts of Hα, white-light flares, and show radio flares and quiescent radio emission. They are suggested to form aurorae, similar to planets in the solar system, but much more energetic. All these processes require a source gas with an appropriate degree of ionisation, which, so far, is mostly postulated to be sufficient. Aims. We aim to demonstrate that the Galactic environment influences atmospheric ionisation, and that it hence amplifies or enables the magnetic coupling of the atmospheres of ultra-cool objects, like brown dwarfs and free-floating planets. Methods. We build on our previous work on thermal ionisation of ultra-cool atmospheres and explore the effect of environmental high-energy radiation on the degree of ionisation in the atmosphere. We consider the effect of photoionisation by Lyman-continuum radiation in three different environments: in the interstellar radiation field (ISRF), O and B stars in star-forming regions, and in white dwarf companions in binary systems. We apply our Monte Carlo radiation transfer code to investigate the effect of Lyman-continuum photoionisation for prescribed atmosphere structures for very low-mass objects. Results. The external radiation environment plays an important role for the atmospheric ionisation of very low-mass, ultra-cool objects. Lyman-continuum irradiation greatly increases the level of ionisation in the uppermost atmospheric regions. Our results suggest that a shell of an almost fully ionised atmospheric gas emerges for brown dwarfs in star-forming regions and brown dwarfs in white dwarf binary systems. As a consequence, brown dwarf atmospheres can be magnetically coupled, which is the presumption for chromospheric heating to occur and for aurorae to emerge. First tests for assumed chromosphere-like temperature values suggest that the resulting free-free X-ray luminosities are comparable with those observed from non-accreting brown dwarfs in star-forming regions.

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Xia, Guoqing, Chuang Sun, and Bo Zhao. "Output Feedback Cooperative Dynamic Positioning Control for an Unactuated Floating Object Using Multiple Vessels." Journal of Marine Science and Engineering 9, no. 5 (April 24, 2021): 463. http://dx.doi.org/10.3390/jmse9050463.

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This paper proposes an output feedback cooperative dynamic positioning control scheme for an unactuated floating object using multiple vessels under model uncertainties and environmental disturbances. The floating object is connected to multiple vessels through towlines. At first, nonlinear extended state observers are developed for the floating object and vessels to reconstruct the unmeasured velocity and to estimate the model uncertainties and disturbances. Second, observer-based controllers are designed for the floating object and vessels to drive the floating object to track the reference signal and to achieve the cooperative control of multiple vessels, respectively. The salient features of the proposed control scheme are presented as follows. Firstly, by design the object controller, the tracking performance of the object is improved. Secondly, according to the required force of the floating object, the time-varying formation of vessels is obtained by using the towline attachment geometry of the floating object, control allocation and a towline model. It is shown that all signals in closed-loop system are bounded via Lyapunov analysis. Simulation study is carried out to verify the effectiveness of proposed control method.

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Xue, Xiangzhen, Jian Liu, Jipeng Jia, Siwei Yang, and Yifan Li. "Prediction and Experimental Validation of Aviation Floating Involute Spline." Lubricants 10, no. 10 (October 20, 2022): 270. http://dx.doi.org/10.3390/lubricants10100270.

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Based on the research on the wear mechanism of floating involute spline coupling, combined with the traditional Archard wear equation, a wear prediction model of aviation floating involute spline coupling was established. The transient simulation of spline coupling with floating distances of 0 mm, 0.3 mm, and 0.6 mm was carried out using Abaqus, and the accuracy of the theoretical model was verified by analyzing the wear and failure parts of the spline coupling. The analysis results show that there is oxidation wear, adhesive wear, abrasive wear, and other wear forms on the tooth surface of the aviation floating involute spline coupling. Under the influence of the floating distance of the spline coupling, the calculation results are closer to the actual working situations. In addition, with increasing floating distance, the wear depth of the tooth surface increases significantly, and the wear depth becomes larger and larger along the floating end. The above study provides a theoretical basis for designing and maintaining aerospace involute spline couplings.

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Yoo, Sang-Lok, Deug-Bong Kim, and Da-Un Jang. "Spatiotemporal Analysis of Ship Floating Object Accidents." Journal of the Korean Society of Marine Environment and Safety 27, no. 7 (December 30, 2021): 1004–10. http://dx.doi.org/10.7837/kosomes.2021.27.7.1004.

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Seino, Yusuke, Erika Maruyama, Minoru Nomura, and Makoto Ozaki. "A Floating Object in the Left Atrium." Anesthesiology 128, no. 1 (January 1, 2018): 142. http://dx.doi.org/10.1097/aln.0000000000001835.

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Kim, Kwang-sup. "Quantifier Floating and Object Shift in English." Studies in Modern Grammar 99 (September 30, 2018): 1–25. http://dx.doi.org/10.14342/smog.2018.99.1.

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VELLA, DOMINIC, and HERBERT E. HUPPERT. "The waterlogging of floating objects." Journal of Fluid Mechanics 585 (August 7, 2007): 245–54. http://dx.doi.org/10.1017/s002211200700715x.

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We consider the dynamical processes by which a dense, porous object floating in a body of liquid becomes waterlogged and sinks. We first generalize the classic model of capillary rise in a porous medium to present an analytically tractable model of the process, which is valid for objects that are very shallow compared to their horizontal extent. We find an analytical expression for the time taken for the object to sink under this approximation. We use a series of boundary integral simulations to show that decreasing the horizontal extent of the object decreases the time taken to sink. We find that the results of these numerical simulations are in good quantitative agreement with a series of laboratory experiments. Finally, we discuss the implications of our work for pumice fragments, often found floating in open water after a volcanic eruption, occasionally even supporting plant, animal and human remains.

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Li, Qingtai. "Detection of floating objects in river based on improved HRNet." Frontiers in Computing and Intelligent Systems 3, no. 1 (March 22, 2023): 173–76. http://dx.doi.org/10.54097/fcis.v3i1.6363.

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Human activities and other factors lead to a variety of floating objects in rivers, which seriously affect the quality of human life and natural ecological environment. It has become a widely concerned problem for residents and needs to be solved urgently. Relying on manual inspection to find floating objects is extremely low efficiency, urgent need of intelligent technology to detect and warn in time. To solve the problem of river floating object detection, we proposed an improved HRNet method for river floating object detection. Trunk network HRNet was used to replace the original AlexNet trunk network of Faster-RCNN to detect river floating object, which enhanced the feature extraction ability. A backbone combining DenseNet and HRNet is proposed to optimize the ability to extract details and improve the detection accuracy.

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Agrawal, S. K., M. Y. Chen, and M. Annapragada. "Modeling and Simulation of Assembly in a Free-floating Work Environment by a Free-floating Robot." Journal of Mechanical Design 118, no. 1 (March 1, 1996): 115–20. http://dx.doi.org/10.1115/1.2826841.

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Freely moving systems in space conserve linear and angular momentum. As moving systems collide, the velocities get altered due to transfer of momentum. The development of strategies for assembly in a free-floating work environment requires a good understanding of primitives such as self motion of the robot, propulsion of the robot due to onboard thrusters, docking of the robot, retrieval of an object from a collection of objects, and release of an object in an object pool. The analytics of such assemblies involves not only kinematics and rigid body dynamics but also collision and impact dynamics of multibody systems. This paper presents analytical models of assembly, built from the models of primitives, and some possible strategies for overall assembly.

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Yoshimoto, S., H. Sekine, and M. Miyatake. "A non-contact chuck using ultrasonic vibration: Analysis of the primary cause of the holding force acting on a floating object." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 224, no. 2 (February 1, 2010): 305–13. http://dx.doi.org/10.1243/09544062jmes1557.

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It is experimentally known that when a flat surface vibrates vertically at ultrasonic frequencies, both vertical and horizontal forces act on an object placed on the vibrating surface, enabling the vibrating surface to support an object vertically and horizontally without any contact. However, the cause of the horizontal force (called ‘the holding force’ in this article) has not been clarified yet. This article investigates experimentally and numerically the cause of the holding force generated by a vibrating surface. In numerical calculations, computational fluid dynamics was used to obtain the pressure distribution of air surrounding the floating object and the vibrating surface. It was consequently found that the holding force acting on the floating object is due to a negative average pressure generated at the edge of the object floating on the vibrating flat surface.

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Kokko, Ville V. "God is Alive." After Dinner Conversation 4, no. 2 (2023): 57–72. http://dx.doi.org/10.5840/adc20234217.

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If you know God exists, have actual proof, do you still have “faith?” In this work of philosophical short fiction, William gets a strange messages and heads over to visit his friend Thomas, who explains God came to him in a dream. Moreover, God left him proof of his existence, a floating object on a pedestal that, according to Thomas, defies all laws of physics. Thomas declares this floating object a miracle, William is less sure. Thomas says he took it to the local University to investigate and they were unable to find a cause to the floating object. Assuming, Thomas says, the floating object is a miracle, does that mean all of religion is true? Is there a heaven and hell, a God that commands, and absolute right and wrong? After additional discussion, William is interested, but still unsure. Note: This story is a part of our legacy-of-excellence program. It was first printed in After Dinner Conversation - November, 2020 issue.

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Yuan, Junqi, Jian Feng, and Sung Kwon Cho. "Dielectrowetting Control of Capillary Force (Cheerios Effect) between Floating Objects and Wall for Dielectric Fluid." Micromachines 12, no. 3 (March 23, 2021): 341. http://dx.doi.org/10.3390/mi12030341.

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A capillary interaction between floating objects and adjacent walls, which is known as “Cheerios effect”, is a common phenomenon that generates capillary attraction or repulsion forces between them depending on their wettabilities, densities, geometries, and so on. This paper deals with controlling the capillary forces, specifically, acting on objects floating on a dielectric (non-conductive) fluid. A key control input parameter is the wettability (contact angle) of the sidewall adjacent to the floating object. By introducing dielectrowetting to the sidewall and actively changing the contact angle on the sidewall, the capillary force is controlled and easily reversed between attraction and repulsion. In this reversing process, the tilting angle of the sidewall is another critical parameter. A theoretical relation taking the titling angle into account is compared and in good agreement with experimental results obtained from the trajectory of the floating object. Finally, a continuous motion of the floating object is demonstrated using this control where an array of dielectrowetting electrode pads is sequentially activated.

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HARIMA, Kouichi, Jun-ichiro KAWAGUCHI, and Ichiro NAKATANI. "Retraction Control of Floating Object by Space Manipulator." Journal of the Robotics Society of Japan 10, no. 5 (1992): 621–31. http://dx.doi.org/10.7210/jrsj.10.621.

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Ma, Hong Wei, Ji Wei Wang, and Ji Xiang Xu. "Nonlinear Simulation of Interaction between Water and Free Floating Ship." Applied Mechanics and Materials 90-93 (September 2011): 2528–32. http://dx.doi.org/10.4028/www.scientific.net/amm.90-93.2528.

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Based on fluid-solid two-phase coupling numerical model, this paper utilized velocity potential function theory to investigate the nonlinear interaction of water and free floating body. Meanwhile, multi-time step integral method and Overall numerical solution method, which are suitable for finite element dynamic analysis, and free surface boundary condition, not moving boundary conditions and the water-solid coupling boundary conditions are adopted to analyze the dynamic responses of water and free floating body with different dimensions. Numerical results show that the change of floating body sizes can obviously affect the dynamic characteristics of the fluid-solid coupling system, especially in the aspects of the stress responses of the floating body and the pressure responses of the water model.

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Devin, Michael C., Nicole R. Mendoza, Andrew Platt, Kevin Moore, Jason Jonkman, and Brandon L. Ennis. "Enabling Floating Offshore VAWT Design by Coupling OWENS and OpenFAST." Energies 16, no. 5 (March 4, 2023): 2462. http://dx.doi.org/10.3390/en16052462.

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Vertical-axis wind turbines (VAWTs) have a long history, with a wide variety of turbine archetypes that have been designed and tested since the 1970s. While few utility-scale VAWTs currently exist, the placement of the generator near the turbine base could make VAWTs advantageous over tradition horizontal-axis wind turbines for floating offshore wind applications via reduced platform costs and improved scaling potential. However, there are currently few numerical design and analysis tools available for VAWTs. One existing engineering toolset for aero-hydro-servo-elastic simulation of VAWTs is the Offshore Wind ENergy Simulator (OWENS), but its current modeling capability for floating systems is non-standard and not ideal. This article describes how OWENS has been coupled to several OpenFAST modules to update and improve modeling of floating offshore VAWTs and discusses the verification of these new capabilities and features. The results of the coupled OWENS verification test agree well with a parallel OpenFAST simulation, validating the new modeling and simulation capabilities in OWENS for floating VAWT applications. These developments will enable the design and optimization of floating offshore VAWTs in the future.

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Varçin, Hakan, Fatih Üneş, Ercan Gemici, and Martina Zelenakova. "Development of a Three-Dimensional CFD Model and OpenCV Code by Comparing with Experimental Data for Spillway Model Studies." Water 15, no. 4 (February 14, 2023): 756. http://dx.doi.org/10.3390/w15040756.

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This article presents a three-dimensional CFD model and OpenCV code by comparing the flow over the spillway with the experimental data for use in spillway studies. A 1/200-scale experimental model of a real dam spillway was created according to Froude similarity. In the experimental studies, velocity and water depth were measured in four different sections determined in the spillway model. A three-dimensional ANSYS Fluent model of the spillway was created and the simulations of the flows occurring during the flood were obtained. In the numerical model, the two-phase VOF model and k-epsilon turbulence model are used. As a result of the numerical analysis, velocity, depth, pressure, and cavitation index values were examined. The velocity and depth values obtained with models were compared and a good agreement was found between the results. In addition, in this study, a different technique based on image processing is developed to calculate water velocity and depth. A floating object was placed in the spillway channel during the experiment and the movement of the object on the water was recorded with cameras placed at different angles. By using the object tracking method, which is an image processing technique, the position of the floating object was determined in each video frame in the video recordings. Based on this position, the velocity of the floating object and its perpendicular distance to the bottom of the channel was determined. Thus, an OpenCV-Python code has been developed that determines the velocity and water depth of the floating object depending on its position. The floating object velocity values obtained by the algorithm were compared with the velocity values measured during the experimental model, and new velocity correction coefficients were obtained for the chute spillways.

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Steffen, Matthias, Frederico Brito, David DiVincenzo, Shwetank Kumar, and Mark Ketchen. "Decoherence of floating qubits due to capacitive coupling." New Journal of Physics 11, no. 3 (March 25, 2009): 033030. http://dx.doi.org/10.1088/1367-2630/11/3/033030.

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Yoshimoto, S. "Floating Characteristics of Squeeze-Film Gas Bearings With Vibration Absorber for Linear Motion Guide." Journal of Tribology 119, no. 3 (July 1, 1997): 531–36. http://dx.doi.org/10.1115/1.2833533.

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This paper describes the floating characteristics of squeeze-film gas bearings with a vibration absorber. This bearing uses a piezoelectric actuator directly attached to a counterweight to impart oscillations to a bearing surface and, therefore, can generate a squeeze-film between the bearing and the guideway surfaces. Furthermore, in this squeeze bearing, a vibration absorber is inserted between a counterweight and a carried object to reduce the vibrational amplitude of the carried object and improve the motion accuracy. The effects of the vibration absorber on the floating characteristics are discussed theoretically and experimentally. It was found that the material of the vibration absorber greatly affected the floating characteristics, and the absorber made of silicone rubber was very effective to reduce the vibrational amplitude of the carried object.

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Golikov, Victor, Oleg Samovarov, Daria Chernomorets, and Marco Rodriguez-Blanco. "Detection of Multi-Pixel Low Contrast Object on a Real Sea Surface." Mathematics 10, no. 3 (January 27, 2022): 392. http://dx.doi.org/10.3390/math10030392.

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Video images captured at long range often show low-contrast floating objects of interest on a sea surface. A comparative experimental study of the statistical characteristics of reflections from floating objects and from the agitated sea surface showed differences in the correlation and spectral characteristics of these reflections. The functioning of the recently proposed modified matched subspace detector (MMSD) is based on the separation of the observed data spectrum on two subspaces: relatively low and relatively high frequencies. In the literature, the MMSD performance has been evaluated in general and using only a sea model (i.e., additive Gaussian background clutter). This paper extends the performance evaluating methodology for low contrast object detection using only a real sea dataset. The methodology assumes an object of low contrast if the mean and variance of the object and the surrounding background are the same. The paper assumes that the energy spectrum of the object and the sea are different. The paper investigates a scenario in which an artificially created model of a floating object with specified statistical parameters is placed on the surface of a real sea image. The paper compares the efficiency of the classical matched subspace detector (MSD) and MMSD for detecting low-contrast objects on the sea surface. The article analyzes the dependence of the detection probability at a fixed false alarm probability on the difference between the statistical means and variances of a floating object and the surrounding sea.

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Chen, Xuesong, Zhiying Yang, and Yingjie Liu. "Simplified Algorithm of Moving Object Trajectory Based on Interval Floating." Mobile Information Systems 2022 (November 8, 2022): 1–10. http://dx.doi.org/10.1155/2022/5032375.

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This paper proposes an online trajectory simplification algorithm based on interval floating. The accumulated angle deviation is used in the algorithm, and the bounded error theorem of interval floating is presented. First, the accumulated angle deviation starts from the nearest reserved point. Next, the sum of the angle deviations generated by the subsequent trajectory points is continuously calculated. When the simplified threshold is reached for the first time, it is will be judged whether the simplified threshold interval needs to be floated as well as the next reservation in the floating error interval. It is worth noting that the interval between two adjacent reserved points floats only once. The algorithm is tested on real trajectory data, and the experimental results show that the algorithm has an improved simplification rate with a certain simplification error.

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Zhang, Lili, Zhiqiang Xie, Mengqi Xu, Yi Zhang, and Gaoxu Wang. "EYOLOv3: An Efficient Real-Time Detection Model for Floating Object on River." Applied Sciences 13, no. 4 (February 10, 2023): 2303. http://dx.doi.org/10.3390/app13042303.

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At present, the surveillance of river floating in China is labor-intensive, time-consuming, and may miss something, so a fast and accurate automatic detection method is necessary. The two-stage convolutional neural network models appear to have high detection accuracy, but it is hard to reach real-time detection, while on the other hand, the one-stage models are less time-consuming but have lower accuracy. In response to the above problems, we propose a one-stage object detection model EYOLOv3 to achieve real-time and high accuracy detection of floating objects in video streams. Firstly, we design a multi-scale feature extraction and fusion module to improve the feature extraction capability of the network. Secondly, a better clustering algorithm is used to analyze the size characteristics of floating objects to design the anchor box, enabling the network to detect objects more effectively. Then a focus loss function is proposed to make the network effectively overcome the sample imbalance problem, and finally, an improved NMS algorithm is proposed to solve the object suppressed problem. Experiments show that the proposed model is efficient in detection of river floating objects, and has better performance than the classical object detection method and the latest method, realizing real-time floating detection in video streams.

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NGUYEN, Minh Duc, Monotobu IMASATO, Yoichi FUTAKI, and Takayuki ASANUMA. "Development of Track Estimation System for Floating Object Surveillance." Journal of Japan Institute of Navigation 123 (2010): 69–76. http://dx.doi.org/10.9749/jin.123.69.

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KOBAYASHI, Jun, Fujio OHKAWA, and Ryozo KATOH. "Handling of a Floating Object by Several Space Robots." Transactions of the Japan Society of Mechanical Engineers Series C 64, no. 628 (1998): 4710–16. http://dx.doi.org/10.1299/kikaic.64.4710.

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Zhang, Yuling, Yongxia Gu, Tao Liu, Jieliang Zhao, and Shaoze Yan. "Dynamic behavior and parameter sensitivity of the free-floating base for space manipulator system considering joint flexibility and clearance." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 3 (October 23, 2018): 895–910. http://dx.doi.org/10.1177/0954406218806927.

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The joint flexibility and clearance greatly affect the dynamic behavior of the free-floating base when space manipulators operate due to the dynamic coupling between the manipulators and the free-floating base. Based on the Lagrange–Euler method and momentum conservation, the dynamic model of a free-floating space manipulator system with joint flexibility and clearance is obtained. With this model, the coupling effects of joint flexibility and clearance on the dynamic response of the free-floating base are analyzed and some case studies are conducted to investigate the effects of different parameters of joint flexibility and clearance on the free-floating base. Further, the parameter sensitivity of the free-floating base for space manipulator system with joint flexibility and clearance is analyzed using the improved response surface method. According to the analysis of response surface method, we can increase the joint clearance size or decrease the dynamic friction coefficient to improve the stability and motion accuracy of the free-floating base position and attitude. This work points out the direction for reducing the base disturbance and provides a basis for the optimization design for free-floating space manipulator system.

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Almeida, Sílvia, Marko Radeta, Tomoya Kataoka, João Canning-Clode, Miguel Pessanha Pais, Rúben Freitas, and João Gama Monteiro. "Designing Unmanned Aerial Survey Monitoring Program to Assess Floating Litter Contamination." Remote Sensing 15, no. 1 (December 23, 2022): 84. http://dx.doi.org/10.3390/rs15010084.

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Monitoring marine contamination by floating litter can be particularly challenging since debris are continuously moving over a large spatial extent pushed by currents, waves, and winds. Floating litter contamination have mostly relied on opportunistic surveys from vessels, modeling and, more recently, remote sensing with spectral analysis. This study explores how a low-cost commercial unmanned aircraft system equipped with a high-resolution RGB camera can be used as an alternative to conduct floating litter surveys in coastal waters or from vessels. The study compares different processing and analytical strategies and discusses operational constraints. Collected UAS images were analyzed using three different approaches: (i) manual counting (MC), using visual inspection and image annotation with object counts as a baseline; (ii) pixel-based detection, an automated color analysis process to assess overall contamination; and (iii) machine learning (ML), automated object detection and identification using state-of-the-art convolutional neural network (CNNs). Our findings illustrate that MC still remains the most precise method for classifying different floating objects. ML still has a heterogeneous performance in correctly identifying different classes of floating litter; however, it demonstrates promising results in detecting floating items, which can be leveraged to scale up monitoring efforts and be used in automated analysis of large sets of imagery to assess relative floating litter contamination.

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Zehlicke, T., R. Dahl, T. Just, and H.-W. Pau. "Vibroplasty involving direct coupling of the floating mass transducer to the oval window niche." Journal of Laryngology & Otology 124, no. 7 (April 8, 2010): 716–19. http://dx.doi.org/10.1017/s0022215110000526.

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AbstractObjective:To demonstrate the technique and clinical application of vibroplasty in which the floating mass transducer component of the Vibrant Soundbridge implant is coupled directly to the oval window niche, in patients with a mobile stapes footplate but a malformed or destroyed stapes suprastructure.Methods:The underlying concept was to create a soft tissue casing for the floating mass transducer, while also firmly connecting the transducer to a small, solid cartilage ‘plunger’ attached to the stapes footplate. This was realised by removing almost all the cartilage from a larger piece of cartilage–perichondrium, leaving only a tiny cartilage island about half a millimetre in diameter, attached to a much wider ‘blanket’ of perichondrium.Results:By coupling the floating mass transducer directly to the oval window niche, patients' speech understanding was improved. Post-operative aided thresholds of 30–40 dB HL were achieved by all patients.Conclusions:In patients with mixed hearing loss combined with a destroyed stapes suprastructure but a mobile stapes footplate, we describe the coupling of the floating mass transducer component of a Vibrant Soundbridge to the stapes footplate, as an alternative to coupling to the round window.

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Todt, Ingo, G. Rademacher, J. Wagner, P. Mittmann, Dietmar Basta, and Arne Ernst. "Radiological Control of the Floating Mass Transducer Attached to the Round Window." Scientific World Journal 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/902945.

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The surgical rehabilitation of mixed hearing losses can be performed by coupling the floating mass transducer of the Vibrant Soundbridge to the round window. The quality of coupling the floating mass transducer to the round window is crucial for the audiological outcome. It was the aim of this study to further observe the different patterns of floating mass transducer position at the round window. We compared twenty patients with mixed hearing loss implanted with a floating mass transducer attached to the round window and 24 surgeries between 5/2007 and 6/2010. An evaluation of the chronological observation of the flat panel angiography-controlled position of the floating mass transducer at the round window with relation to the surgical report and the audiological outcome was done. We observed no changes in the mean pre- and postbone conduction thresholds. The floating mass transducer position was variable and could be radiologically classified and correlated with the audiologically outcome. A learning curve was observed from the earlier to later implantations. Postoperative, radiological evaluation of the location and angle of the floating mass transducer by means of flat panel tomography allowed us to classify the floating mass transducer position at the round window into 4 groups.

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Su, Qing, Jamil Kawa, Charles Chiang, and Yehia Massoud. "Accurate modeling of substrate resistive coupling for floating substrates." ACM Transactions on Design Automation of Electronic Systems 11, no. 1 (January 2006): 44–51. http://dx.doi.org/10.1145/1124713.1124717.

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Halvorsen, I. J., I. Dejanović, Ž. Olujić, and S. Skogestad. "Thermal coupling opportunities for floating natural gas liquefaction plants." Chemical Engineering Research and Design 147 (July 2019): 346–53. http://dx.doi.org/10.1016/j.cherd.2019.05.013.

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Freunberger, Roman, Wolfgang Klimesch, Birgit Griesmayr, Paul Sauseng, and Walter Gruber. "Alpha phase coupling reflects object recognition." NeuroImage 42, no. 2 (August 2008): 928–35. http://dx.doi.org/10.1016/j.neuroimage.2008.05.020.

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Tang, Yao, Pei Hu, Qian Hao, Shan Yi Fang, and Shi Long Xing. "The Real-Time Fault Analysis of Personal Escape Suit Based on the Object Oriented Model." Advanced Materials Research 1030-1032 (September 2014): 1837–40. http://dx.doi.org/10.4028/www.scientific.net/amr.1030-1032.1837.

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According the actual equipment support demand of rapidly floating escape suit, this paper built the object oriented fault tree model for the rapidly floating escape suit, detailed descried the planning and realization method of the fault detection and analysis system with actual examples.

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Karczewski, Artur, and Łukasz Piątek. "The Influence of the Cuboid Float’s Parameters on the Stability of a Floating Building." Polish Maritime Research 27, no. 3 (September 1, 2020): 16–21. http://dx.doi.org/10.2478/pomr-2020-0042.

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AbstractUsually, the concept of sufficient stability of a floating structure is connected with the capacity to keep a small heel angle despite the moment of heeling. The variable responsible for these characteristics is the initial metacentric height, which is the relation between the hydrostatic features of the pontoon and the mass properties of the entire object. This article answers the questions of how heavy the floating system should be, what the minimum acceptable draft is, and whether it is beneficial to use internal fixed ballast. To cover various technologies, a theoretical model of a cuboid float with average density representing different construction materials was analysed. The results indicate that the common practice of using heavy and deep floating systems is not always reasonable. In the case of floating buildings, which, unlike ships, can be exploited only under small heel angles, the shape and width of the submerged part of the object may influence the stability more than the weight or draft.

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Jia, Qingxuan, Bonan Yuan, Gang Chen, and Yingzhuo Fu. "Kinematic and Dynamic Characteristics of the Free-Floating Space Manipulator with Free-Swinging Joint Failure." International Journal of Aerospace Engineering 2019 (September 12, 2019): 1–22. http://dx.doi.org/10.1155/2019/2679152.

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For the free-floating space manipulator with free-swinging joint failure, motions among its active joints, passive joints, free-floating base, and end-effector are coupled. It is significant to make clear all motion coupling relationships, which are defined as “kinematic coupling relationships” and “dynamic coupling relationships,” inside the system. With the help of conservation of system momentum, the kinematic model is established, and velocity mapping relation between active joints and passive joints, velocity mapping relation between active joints and base, velocity mapping relation between active joints and end-effector. We establish the dynamic model based on the Lagrange equation, and the system inertia matrix is partitioned according to the distribution of active joints, passive joints, and the base. Then, kinematic and dynamic coupling relationships are explicitly derived, and coupling indexes are defined to depict coupling degree. Motions of a space manipulator with free-swinging joint failure simultaneously satisfy the first-order nonholonomic constraint (kinematic coupling relationships) and the second-order nonholonomic constraint (dynamic coupling relationships), and the manipulator can perform tasks through motion planning and control. Finally, simulation experiments are carried out to verify the existence and correctness of the first-order and second-order nonholonomic constraints and display task execution effects of the space manipulator. This research analyzes the kinematic and dynamic characteristics of the free-floating space manipulator with free-swinging joint failure for the first time. It is the theoretical basis of free-swinging joint failure treatment for a space manipulator.

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Chee, Seonkoo, Jaemyung Ryu, and Hojong Choi. "New Optical Design Method of Floating Type Collimator for Microscopic Camera Inspection." Applied Sciences 11, no. 13 (July 4, 2021): 6203. http://dx.doi.org/10.3390/app11136203.

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Recently released mobile phone cameras are capable of photographing objects at a fairly close distance. In addition, the field angle from the camera has increased. To measure the resolution of a mobile phone camera, the target must be photographed. To measure the resolution according to the object distance change from a mobile phone camera with a wide field angle, the target size must be large, whereas the target position must be moved. However, the target size cannot be changed. A virtual object for the target was created using a collimator. Moving a part of the lens group constituting the collimator also changes the virtual object distance. If the amount of change in the virtual object distance is large, the resolution of the collimator may also change. Therefore, a collimator that maintains the resolution even when the distance of the virtual object changes is designed as a floating type in which two lens groups move. Therefore, we propose a new floating collimator optical system that can inspect the resolution of mobile phone cameras from infinity to a close range to compensate for aberrations caused by object distance changes.

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Vandamme, Johan, Qingping Zou, and Dominic E. Reeve. "Modeling Floating Object Entry and Exit Using Smoothed Particle Hydrodynamics." Journal of Waterway, Port, Coastal, and Ocean Engineering 137, no. 5 (September 2011): 213–24. http://dx.doi.org/10.1061/(asce)ww.1943-5460.0000086.

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Magyary, István. "Floating novel object recognition in adult zebrafish: a pilot study." Cognitive Processing 20, no. 3 (February 27, 2019): 359–62. http://dx.doi.org/10.1007/s10339-019-00910-5.

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Busch, Susan, Thomas Lenarz, and Hannes Maier. "Comparison of Alternative Coupling Methods of the Vibrant Soundbridge Floating Mass Transducer." Audiology and Neurotology 21, no. 6 (2016): 347–55. http://dx.doi.org/10.1159/000453354.

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The active middle ear implant Vibrant Soundbridge© provides a variety of coupling modalities of the floating mass transducer (FMT) to various structures of the ossicular chain and the round window. A retrospective analysis was performed on 125 subjects (n = 137 ears) (1) to compare the efficacy of the different FMT coupling modalities with increasing degree of hearing loss, (2) to compare the performance in speech outcome and the effective gain between the coupling types, and (3) to evaluate the risk of additional hearing loss of each coupling procedure. The patients were grouped according to their type of FMT coupling into incus vibroplasty (incus group, n = 59), round window vibroplasty with coupler (RWC group, n = 23), round window vibroplasty without coupler (RW group, n = 22), and oval window vibroplasty with coupler (OWC group, n = 33). For each coupling group, pre- and postoperative thresholds, the results of the Freiburg monosyllable test at 65 dB SPL, and the effective gain across frequencies (0.5-6 kHz) were evaluated. A logistic regression function was used to describe the relationship between word recognition scores (WRS, in % correct) and the mean bone conduction (BC) hearing loss. The surgical procedure had no clinically relevant effect on BC thresholds of patients in each coupling group. The BC pure tone average (PTA4) for 50% WRS predicted by the model function was similar for the incus (48.2 dB nHL), RW (47.8 dB nHL), and OWC (49.0 dB nHL) groups, but higher for the RWC group (67.9 dB nHL). However, the median WRS was 80% or better with no significant differences in speech perception between coupling types (Kruskal-Wallis test, p = 0.229). The effective gain shows an advantage for the incus coupling between 0.5 and 2 kHz over the other coupling types. The performance of the FMT coupling modalities is equally good for patients with a mild-to-moderate hearing loss, but the efficacy of coupling types differs for patients with greater hearing loss (>48 dB BC HL).

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Yao, Yisheng, Dezhi Ning, Sijia Deng, Robert Mayon, and Ming Qin. "Hydrodynamic Investigation on Floating Offshore Wind Turbine Platform Integrated with Porous Shell." Energies 16, no. 11 (May 28, 2023): 4376. http://dx.doi.org/10.3390/en16114376.

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As the siting of wind turbines increasingly transitions from shallow water to offshore deep-water locations, improving the platform stability of floating offshore wind turbines is becoming a growing concern. By coupling a porous shell commonly used in traditional marine structures, with a FOWT (floating wind turbine platform), a new spar-buoy with a porous shell was designed. A numerical model investigating the coupling effect of the aero-hydro-mooring system is developed, and the results of the motion response are compared with the OC3-Hywind spar. The motion response of the two platforms was simulated in the time-domain with the incident wave period varied in the range of 5~22 s. The exciting wave force with added mass and radiation damping of the spar with the porous shell is compared with the OC3-Hywind spar. The results demonstrate that the motion response amplitude of the spar with the porous shell decreases in all three main motion freedoms (i.e., surge, heave and pitch, etc.), among which the heave motions are most significantly attenuated. The study shows that the coupling of porous shells with a floating platform to achieve the reduced motion responses is feasible and can be an innovative structure for the development of deep-sea offshore floating wind turbines.

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Huang, Kai, Hong Bai Bai, Dong Wei Li, and Yu Long Li. "Coupling Dynamic Analysis of Floating Slab Track in the Urban Rail Transit." Applied Mechanics and Materials 253-255 (December 2012): 2047–51. http://dx.doi.org/10.4028/www.scientific.net/amm.253-255.2047.

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In order to study how the parameters of floating slab track and the speed of the train influence the vehicle-track coupling system，the paper built the vehicle-track coupling dynamic system. In the coupling model, the train is simplified a multi-rigid body system. The rail and the floating slab are considered as Euler beam. The wheel-rail relation is regarded as non-linear Hertz contact. The paper solved the dynamic equation of the vehicle-track coupling dynamic system with prediction-correction Newmark-β numerical integration method. Through numerical simulation, the paper gained the affect of fastener stiffness, slab support stiffness, and the speed of train to the characteristic of the coupling system containing the vehicle acceleration, wheel-rail force, the vibration of the track and the counter-force from the basis. The paper provides a reference for the selection of the track parameters and the speed of vehicle.

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Dagorn, Laurent, and Pierre Fréon. "Article." Canadian Journal of Fisheries and Aquatic Sciences 56, no. 6 (June 1, 1999): 984–93. http://dx.doi.org/10.1139/f98-209.

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Among the different assumptions proposed to explain why tropical tuna aggregate around floating objects ("logs"), one of the most recent is that floating objects may represent meeting points for tuna. This "meeting point hypothesis" proposes that tuna can use these floating objects to form larger schools after school fission or dispersion. The influence of meeting points on tuna school sizes is explored through different individual-based models that consider a single fusion rule and a variety of fission rules based on energetic considerations, the role of school size on school cohesion, predator attacks, and dispersion during the night. Results are first analyzed using an averaging approach to study the overall mean school size in habitats having different floating object densities. Second, a dynamic approach is used to compare the temporal dynamics of associated and free-swimming school sizes. The averaging approach indicates that in all the models (except those based on energetics), floating objects increase school size, at least up to a certain object density. The dynamic approach clearly illustrates different dynamics in the school size of associated and free-swimming schools. Most of our models show that tuna associated with logs resume schooling in larger schools after fission events.

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Shi, Guangtian, Jianjin Yang, and Xinwen Yang. "Parameter Influences of Light Floating Slab on Its Vertical Vibration Excited by Track Irregularity." Open Mechanical Engineering Journal 8, no. 1 (September 16, 2014): 206–13. http://dx.doi.org/10.2174/1874155x01408010206.

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According to the structure characteristics of railway viaduct with light floating slabs, a frequency domain dynamic model of the vehicle-light floating slab track-viaduct bridge vertical coupling system is established. The Green functions are used to quickly calculate the receptance response of the system, and then the pseudo excitation method is used to further analyze the parameter influences of the floating slab on the vertical vibration excited by the track irregularity. The parameters of the floating slab have obvious effects on its vertical vibration, so as we strive to reduce the vibration and noise radiation of the railway by changing the parameters of the floating slab, the disadvantages to the vibration and noise control of the floating slab have to be taken into consideration.

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Oh, Young-Cheol, Ok-Sok Gim, and Jae-Yong Ko. "Hydrodynamic-Structural Response Coupling Analysis to a Rectangle Floating Structures." Journal of the Korean Society of Marine Environment and Safety 18, no. 6 (December 31, 2012): 577–83. http://dx.doi.org/10.7837/kosomes.2012.18.6.577.

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Journal articles on the topic 'Coupling with floating object'

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