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Journal articles on the topic 'POD propulsion'

Author: Grafiati

Published: 4 June 2021

Last updated: 8 June 2024

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Lea, Michelle, Donald Thompson, BillVan Blarcom, Jon Eaton, Juergen Friesch, and John Richards. "Scale Model Testing of a Commercial Rim-Driven Propulsor Pod." Journal of Ship Production 19, no. 02 (2003): 121–30. http://dx.doi.org/10.5957/jsp.2003.19.2.121.

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Podded propulsion is gaining more widespread use in the marine industry and is prevalent in newer cruise ships in particular. This propulsion system can provide many advantages to the ship owner that include increased propulsion efficiency, arrangement flexibility, payload, and harbor maneuverability. A new, unique podded propulsor concept is being developed that allows optimization of each element of the system. The concept comprises a ducted, multiple-blade row propulsor with a permanent magnet, radial field motor rotor mounted on the tips of the propulsor rotor blades, and the motor stator mounted within the duct of the propulsor. This concept, designated a commercial rim-driven propulsor pod (CRDP), when compared to a conventional hub-driven pod (HDP), offers improved performance in a number of areas, including equal or improved efficiency, cavitation, and hull unsteady pressures. The combination of these CRDP performance parameters allows the ship designer much greater flexibility to provide improved ship performance as compared to that of an HDP. A CRDP is being developed to power a panamax-size cruise vessel. The paper addresses the hydrodynamic performance of that CRDP design demonstrated at 1/25th scale as tested at the Hamburg Ship Model Basin, Hamburg Germany (HSVA).

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Savenko, V. V., and Yu F. Shlemov. "Small silent vessel with pod propulsion." Transactions of the Krylov State research Centre 3, no. 381 (2017): 123–28. http://dx.doi.org/10.24937/2542-2324-2017-3-381-123-128.

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Van Dine, Piet. "Manufacture of a Prototype Advanced Permanent Magnet Motor Pod." Journal of Ship Production 19, no. 02 (2003): 91–97. http://dx.doi.org/10.5957/jsp.2003.19.2.91.

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Podded propulsion is prevalent in the marine industry. Podded propulsion systems provide many advantages to the ship owner, including increased propulsion efficiency and reduced construction cost. To evaluate the potential of a new pod configuration, a prototype machine was constructed and tested. This prototype machine was mainly constructed of composite parts. The propeller, housings, structural blading, motor canning, and fairings were constructed of composite materials. Composite materials were chosen as a cost saving, schedule reduction, performance enhancement, and as a technology demonstration. This paper will review the unit construction, and test results, focusing on the lessons learned for the composite part manufacture.

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Mei, Ziyi, Bo Gao, Ning Zhang, Yuanqing Lai, and Guoping Li. "Numerical Study on the Unsteady Flow Field Characteristics of a Podded Propulsor Based on DDES Method." Energies 15, no. 23 (2022): 9117. http://dx.doi.org/10.3390/en15239117.

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The podded propulsor has gradually become an important propulsion device for high technology ships in recent years because of its characteristics of high maneuverability, high efficiency, low noise, and vibration. The performance of podded propulsor is closely related to its flow field. To study the unsteady flow field characteristics of podded propulsor, the DDES (delayed detached eddy simulation) method was used to carry out high-precision transient numerical simulations. Results showed that the pod has a significant influence on the unsteady flow field. The rotor–stator interaction between the propeller and pod can be observed, leading to the periodic fluctuation of thrust on the propeller. On the surface of pod, pressure distribution changes with time, leading to the difference of local lateral force. In the spatial region affected by the propeller wake flow, pressure distribution presents a spiral characteristic, both in the region far away from the pod, and in the region of the wake flow of strut and fin. The vortex structures of podded propulsor are complex since the interference of the pod. In addition to the tip, root and hub vortex, strut and fin vortices also occur. The vortices generated by the effect of mutual inductance between vortices are also discussed.

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Aksu, Serap, Seref Aksu, and Osman Turan. "Reliability and Availability of Pod Propulsion Systems." Quality and Reliability Engineering International 22, no. 1 (2006): 41–58. http://dx.doi.org/10.1002/qre.747.

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Naik, P. M., B. J. Darekar, J. S. Unde, and P. R. Dhamangaokar. "Cold Gas Propulsion System for Hyperloop Pod Chassis." Journal of Physics: Conference Series 1276 (August 2019): 012081. http://dx.doi.org/10.1088/1742-6596/1276/1/012081.

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Fan, Yunsheng, Dongdong Mu, Xianku Zhang, Guofeng Wang, and Chen Guo. "Course keeping Control Based on Integrated Nonlinear Feedback for a USV with Pod-like Propulsion." Journal of Navigation 71, no. 4 (2018): 878–98. http://dx.doi.org/10.1017/s0373463318000024.

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In this paper, a response model of an Unmanned Surface Vehicle (USV) with a pod-like propulsion device is established. To improve the robustness of motion control in heavy sea states, an integrated nonlinear feedback course-keeping controller is proposed. First, to establish a response model of a USV with pod-like propulsion, model parameters are obtained by the method of system identification, then an integrated nonlinear feedback control strategy is proposed. The essence of this method is to make the original error signal pass through a nonlinear function, and then the output of this function is used to replace the original error signal. Simulation results show that under ordinary sea states, nonlinear feedback can save up to 34.5% of energy used compared with standard feedback methods; under heavy sea states, this can rise to 40.8%. A set of field experiments were carried out with a USV with pod-like propulsion. Results show that under heavy sea states, the test USV can maintain the target course well, which proves the correctness of the model and the robustness of the proposed method.

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Andryushin, A. "Ice loads on pod unit bodies of ice-going ships." Transactions of the Krylov State Research Centre S-I, no. 2 (2020): 19–30. http://dx.doi.org/10.24937/2542-2324-2020-2-s-i-19-30.

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This paper presents the methodology for determination of ice loads on the elements of pod propulsion units for Arc4-Arc9 ships. The conclusion gives calculation results for ice loads on pod units for Arc5 and Arc7 ships, and compares these results with those obtained as per DNV-GL rules for ice classes PC6, PC5, PC3

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Chen, Changsheng, Guoping Li, Zhenlai Ma, Ziyi Mei, Bo Gao, and Ning Zhang. "A Numerical Study of the Hydrodynamic Noise of Podded Propulsors Based on Proper Orthogonal Decomposition." Journal of Marine Science and Engineering 11, no. 11 (2023): 2054. http://dx.doi.org/10.3390/jmse11112054.

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Podded propulsors have become a focal point of research in the field of marine propulsion in recent years due to their high efficiency, low noise, and excellent maneuverability. To investigate the acoustic characteristics induced by the flow field of podded propulsors, a high-precision unsteady numerical simulation was conducted using the Delayed Detached Eddy Simulation (DDES) coupled with Ffowcs Williams–Hawkings (FW-H) equations. Multiple spatial acoustic receiving arrays were employed, and analysis methods including Proper Orthogonal Decomposition (POD) and Fast Fourier Transform (FFT) were utilized to determine the spatial distribution of the acoustic field of the podded propulsor. The results show that the blade passing frequency and the shaft frequency consistently dominate as the primary characteristic frequencies. On the plane of the propeller disk, the distribution of sound pressure levels is uniform without distinct directivity. Across the space curved surface, approximately the first ten POD modes encompass 99.8% of the total energy, and their spatial distribution characteristics of sound pressure are closely related to the pod structure. Additionally, these modes exhibit characteristic frequencies such as the blade passing frequency and shaft frequency. The spatial distribution of sound pressure at a single frequency on the spatial surface corresponds well with the results obtained from the POD analysis.

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Samoilescu, Gheorghe, Dumitru Iorgulescu, Robert Mitrea, and Laura D. Cizer. "Propulsion Systems in Marine Navigation." International conference KNOWLEDGE-BASED ORGANIZATION 24, no. 3 (2018): 78–82. http://dx.doi.org/10.1515/kbo-2018-0140.

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Abstract This paper presents variants of propulsion systems as the main factor in the analysis and design of the power system of a sea-going or river vessel; this topic is also under research study within two doctoral theses. The analysis of the ship - main propulsion- thruster assembly is made according to the requirements imposed by the market economy. The parameters to be considered when choosing a propulsion system are: the cost of the investment, the specific cost of transport that depends both on the specific fuel consumption and on the number and level of pay of the crew members operating the propulsion system, the propulsion efficiency, the high safety in handling, and the control accessibility during operation. The Pod and Azipod propulsion systems are analyzed in terms of advantages and disadvantages compared to conventional propulsion systems. The azimuth thrusters can ensure maximum push in any direction regardless the speed of the ship, and thus can change the course of the ship according to its handling needs. The azimuth thrusters do not only operate in horizontal but also in oblique angles, providing the ship with great maneuverability, even at low speeds, where classical rudder systems have poor performance

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Kim, Myoung-Jun, and Gyu-Hoon Chea. "Study on Catamaran Type Solar Boat Using the Pod Propulsion System." Journal of the Korean Society of Marine Environment and Safety 17, no. 2 (2011): 161–66. http://dx.doi.org/10.7837/kosomes.2011.17.2.161.

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Woodward, Michael D., Mehmet Atlar, and David Clarke. "Application of the IMO Maneuvering Criteria for Pod-Driven Ships." Journal of Ship Research 53, no. 02 (2009): 106–20. http://dx.doi.org/10.5957/jsr.2009.53.2.106.

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The fundamental objective of this paper is to make qualified assessment of the validity of the International Maritime Organization (IMO) maneuvering criteria "Resolution MSC.137(76)," when applied to pod-driven ships. The performance limits given by the criteria provide an adequate benchmark to compare all ships, regardless of propulsion type. However, the application of specific helm angle is less well defined as azimuthing pod drives, like any vectoring thrusters, can be turned to any helm angle, with no specific definition for the angle of maximum force. To address this problem, new methods for modeling the hydrodynamic reaction for both the ship hull and pod drive are identified. Then, a dedicated numerical tool is developed and simulation study conducted exploring systematic variation of applied helm angles with comparison of time-and frequency-domain responses. The study reaches the definitive conclusion that the criteria provides equivalent information about the maneuvering response of pod-driven ships as for conventionally propelled ships and can thus be applied directly.

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Makarov, Vladislav, and Aleksey Troitskiy. "Vibration-based assessment method for operational modes and technical condition of marine equipment." Transactions of the Krylov State Research Centre, SPECIAL ISSUE 1 (April 16, 2019): 189–94. http://dx.doi.org/10.24937/2542-2324-2019-1-s-i-189-194.

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This paper suggests a vibration-based method to determine technical condition of marine equipment, with identification of spectral masks and threshold values for diagnostic parameters needed to assess current operational model of given marine equipment. This method has been tried out on a prototype of DRK-2500 pod propulsion unit at its manufacturer’s test rig located in the town of Severodvinsk.

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Gierusz, Witold. "Modelling the Dynamics of Ships with Different Propulsion Systems for Control Purpose." Polish Maritime Research 23, no. 1 (2016): 31–36. http://dx.doi.org/10.1515/pomr-2016-0005.

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Abstract Two different propulsion systems are analyzed from point of view of future control applications. The traditional one consists of a pushing single screw propeller and a blade rudder. The other system is based on pod (pods): pulling or pushing ones. The equations describing forces and moments generated in both systems, are presented. Exemplary results of a simulation in comparison to the real-time experiments for two ships are also shown.

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Dymarski, Czesław, and Wojciech Leśniewski. "Numerical investigations of the engine cooling system in a small power vessel pod propulsion system." Polish Maritime Research 15, no. 4 (2008): 59–65. http://dx.doi.org/10.2478/v10012-007-0098-6.

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Numerical investigations of the engine cooling system in a small power vessel pod propulsion system The development of electronics and electrotechnology enabled to put electric motors of the alternating current in the pod and to use them for the main drive of ships. A lot of heat which must be picked up from the system is a problem which is turning up at applying the system of this type. Many big ships lately contended with these problems. Building the small propeller for the boat powered with solar power we decided to check the influence of the chilling middle on the temperature of the work of an engine. In the article we are presenting a built propeller and a way, into which an issue of the exchange of the heat was analysed using the Fluent software.

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TERADA, Daisuke, Yasuo YOSHIMURA, Motohisa ABE, and Hironao TAKAHASHI. "Investigation on Maneuverability of a POD Propulsion Ship by Free-Running Model Experiments." Journal of Japan Institute of Navigation 143 (2020): 48–56. http://dx.doi.org/10.9749/jin.143.48.

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Aksu, S., S. K. Aksu, and O. Turan. "Quantitative reliability and availability analysis for design evaluation of generic pod propulsion systems." Proceedings of the Institution of Mechanical Engineers, Part O: Journal of Risk and Reliability 221, no. 1 (2007): 13–28. http://dx.doi.org/10.1243/1748006xjrr40.

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Wang, Xin, Zhongju Ye, Shen Lin, Lin Wei, and Lehui Xiao. "Nanozyme-Triggered Cascade Reactions from Cup-Shaped Nanomotors Promote Active Cellular Targeting." Research 2022 (June 21, 2022): 1–15. http://dx.doi.org/10.34133/2022/9831012.

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Self-propelled nanomotors have shown enormous potential in biomedical applications. Herein, we report on a nanozyme-powered cup-shaped nanomotor for active cellular targeting and synergistic photodynamic/thermal therapy under near-infrared (NIR) laser irradiation. The nanomotor is constructed by the asymmetric decoration of platinum nanoparticles (PtNPs) at the bottom of gold nanocups (GNCs). PtNPs with robust peroxidase- (POD-) like activity are employed not only as propelling elements for nanomotors but also as continuous O2 generators to promote photodynamic therapy via catalyzing endogenous H2O2 decomposition. Owing to the Janus structure, asymmetric propulsion force is generated to trigger the short-ranged directional diffusion, facilitating broader diffusion areas and more efficient cellular searching and uptake. This cascade strategy combines key capabilities, i.e., endogenous substrate-based self-propulsion, active cellular targeting, and enhanced dual-modal therapy, in one multifunctional nanomotor, which is crucial in advancing self-propelled nanomotors towards eventual therapeutic agents.

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Chen, Weimin, Jiachen Ma, Jian Hu, and Li Zhang. "Numerical Simulation of Hydrodynamic Performance of Podded Propulsion under Maneuvering Condition." Journal of Marine Science and Engineering 11, no. 4 (2023): 874. http://dx.doi.org/10.3390/jmse11040874.

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Podded propulsion offers excellent maneuverability without the need for mechanically complex transmission systems. However, the hydrodynamic performance of podded propulsion under maneuvering conditions has not yet been adequately investigated. This study proposes a Reynolds-averaged Navier–Stokes (RANS)-based method to investigate the hydrodynamic performance of pod thrusters under maneuvering conditions. The accuracy of the numerical method is verified based on a comprehensive convergence analysis and experimental comparison. A comparative analysis of the difference in thrust, moment and their coefficients between maneuvering and steady-state conditions is performed. Additionally, the impact of the advance number on the propeller hydrodynamic performance under maneuvering conditions is examined. The results demonstrate that the thrust coefficient and the torque coefficient of the propeller at positive and negative oblique flow angles exhibit asymmetry owing to the influence of the incoming flow velocity. Furthermore, the thrust and torque under maneuvering conditions increase significantly compared with those under the steady-state condition.

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Zhang, Qun, Jian-Chun Yu, Wei-Ming Kang та Guang-Jin Zhu. "Effect of ω-3 Fatty Acid on Gastrointestinal Motility after Abdominal Operation in Rats". Mediators of Inflammation 2011 (2011): 1–4. http://dx.doi.org/10.1155/2011/152137.

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Objective. To investigate whether ω-3 fatty acid could stimulate gastrointestinal motility after abdominal operation.Method. Wistar rats were randomly divided into 3 group (normal saline group, intralipid group, and ω-3 fatty acid group,n=18/group) after partial caecectomy and gastrostomosis, each group was divided into 3 groups (POD1, POD3, and POD6,n=6/group). Serum gastrin (GAS), motilin (MTL), interleukin-1 (IL-1), interleukin-6 (IL-6), tissue necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2), gastric emptying rate, and small bowel propulsion rate were measured.Results. On POD 3, gastric emptying rate and small bowel propulsion rate in ω-3 fatty acid group were higher than those in normal saline group and intralipid group. Serum GAS and MTL levels in ω-3 fatty acid group were higher than those in normal saline group, but serum IL-1, IL-6, TNF-α, and COX-2 levels were lower than those in normal saline group and intralipid group.Conclusion. ω-3 fatty acid could accelerate the recovery of gastrointestinal mobility after abdominal operation in rats, mainly by relieving postoperative inflammation.

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Candeloro, Paolo, Edoardo Martellini, Robert Nederlof, Tomas Sinnige, and Tiziano Pagliaroli. "An Experimental Study of the Aeroacoustic Properties of a Propeller in Energy Harvesting Configuration." Fluids 7, no. 7 (2022): 217. http://dx.doi.org/10.3390/fluids7070217.

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The aim of the present manuscript is to investigate the noise footprint of an isolated propeller in different flight configurations for the propulsion of a hybrid-electric aircraft. Experimental tests were performed at the Low-Turbulence Tunnel located at Delft University of Technology with a powered propeller model and flush-mounted microphones in the tunnel floor. The propeller was investigated at different advance ratios in order to study the noise impact in propulsive and energy harvesting configurations. For brevity, this work only reports the results at the conditions of maximum efficiency in both propulsive and energy harvesting regimes, for a fixed blade pitch setting. Comparing these two configurations, a frequency-domain analysis reveals a significant modification in the nature of the noise source. In the propulsive configuration, most of the energy is related to the tonal noise component, as expected for an isolated propeller; however, in energy harvesting configuration, the broadband noise component increases significantly compared to the propulsive mode. A more detailed analysis requires separation of the two noise components and, for this purpose, an innovative decomposition strategy based on proper orthogonal decomposition (POD) has been defined. This novel technique shows promising results; both in the time and in the Fourier domains the two reconstructed components perfectly describe the original signal and no phase delays or other mathematical artifices are introduced. In this sense, it can represent a very powerful tool to identify noise sources and, at the same time, to define a proper control strategy aimed at noise mitigation.

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Wang, Zhan-Zhi, Ying Xiong, Rui Wang, and Chen-hua Zhong. "Numerical investigation of the scale effect of hydrodynamic performance of the hybrid CRP pod propulsion system." Applied Ocean Research 54 (January 2016): 26–38. http://dx.doi.org/10.1016/j.apor.2015.10.006.

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Trägärdh, P., P. Lindell, and N. Sasaki. "Double Acting Tanker: Experiences from Model Tests and Sea Trials." Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment 219, no. 3 (2005): 109–19. http://dx.doi.org/10.1243/147509005x10413.

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The acronym DAT stands for double acting tanker, a concept where the ship is designed to run astern in heavy ice conditions while remaining hydrodynamically efficient for ahead propulsion in open water conditions. Two large aframax DATs - 106.000 dwt (deadweight tons) each - have been delivered by Sumitomo Heavy Industries to Fortum Oil and Gas OY. They are the first crude carriers built according to the DAT principle and also the first using pod propulsion from the beginning (Fig. 1). They will also be the world's largest crude carriers with ice class 1A super and are primarily intended for year-round transportation of North Sea crude to Fortum's refineries in the Gulf of Finland. The ships were appointed ‘ship of the year’ in Japan in 2003. SSPA was contracted by Sumitomo Heavy Industries to perform model tests. A comprehensive open water model test programme was used to investigate aspects of resistance and propulsion, manoeuvring, and cavitation performance. As the ship is designed to operate both in ahead and astern conditions for prolonged periods of time, most tests were performed both ahead and astern. Also, a simulation study of dynamic positioning at buoy or floating production, storage offshore (FPSO) loading was made by SSPA. Comprehensive tests of the ship's performance in ice were performed in the ice tank at MARC (Masa-Yards Artic Research Centre). The eight-month model testing and development campaign resulted in a ship with excellent propulsion and manoeuvring performance, especially with regard to the high ice class. Sea trials carried out with ship in August 2002 confirmed the results of the model test. Interesting experiences of the model test campaign and comparison between model test and sea trial results are presented, as well as some examples of single-point mooring simulations.

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Mousaviraad, Maysam, Michael Conger, Shanti Bhushan, Frederick Stern, Andrew Peterson, and Mehdi Ahmadian. "Coupled computational fluid and multi-body dynamics suspension boat modeling." Journal of Vibration and Control 24, no. 18 (2017): 4260–81. http://dx.doi.org/10.1177/1077546317722897.

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Multiphysics modeling, code development, and validation by full-scale experiments is presented for hydrodynamic/suspension-dynamic interactions of a novel ocean vehicle, the Wave Adaptive Modular Vessel (WAM-V). The boat is a pontoon catamaran with hinged engine pods and elevated payload supported by suspension and articulation systems. Computational fluid dynamics models specific to WAM-V are developed which include hinged pod dynamics, water-jet propulsion modeling, and immersed boundary method for flow in the gap between pontoon and pod. Multi-body dynamics modeling for the suspension and upper-structure dynamic is developed in MATLAB Simulink. Coupled equations of motion are developed and solved iteratively through either one-way or two-way coupling methods to converge on flow-field, pontoon motions, pod motions, waterjet forces, and suspension motions. Validation experiments include cylinder drop with suspended mass and 33-feet WAM-V sea-trials in calm water and waves. Computational results show that two-way coupling is necessary to capture the physics of the interactions. The experimental trends are predicted well and errors are mostly comparable to those for rigid boats, however, in some cases the errors are larger, which is expected due to the complexity of the current studies. Ride quality analyses show that WAM-V suspension is effective in reducing payload vertical accelerations in waves by 73% compared to the same boat with rigid upper-structure.

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Zhao, Dagang, Chunyu Guo, Jianfeng Lin, Zuotian Zhang, and Xue Bai. "Prediction of Self-Propulsion Performance of Ship Model with Double L-Type Podded Propulsors and Conversion Method for Full-Scale Ship." Journal of Marine Science and Engineering 7, no. 5 (2019): 162. http://dx.doi.org/10.3390/jmse7050162.

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In this study, the self-propulsion performance of a ship model with double-L-type podded propulsors was predicted. Additionally, a conversion method for the performance of a full-scale ship was established based on the correction method published by the International Towing Tank Conference (ITTC) for the scaling effect of a single podded propeller and research reports on pod tests conducted by different ship research institutes. The thrust deduction and wake fraction of the ship were also analyzed. Furthermore, the self-propulsion performance of a full-scale ship with double L-type pods was determined, the full- and model-scale ships compared in terms of their flow fields and pressure charts, and the influence of the scaling effect analyzed. In addition, the calculation results were compared with the conversion results of a full-scale ship, and the reliability of the method adopted for the performance estimation of a full-scale ship with double podded propulsors was verified. The findings reported herein can provide statistics and technical support for the design of L-type podded propulsors and their application in full-scale ships, which are of theoretical significance and practical value in the engineering domain.

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Vineeth, V. K., and Devendra Kumar Patel. "Propulsion performance and wake transitions of a customized heaving airfoil." International Journal of Modern Physics C 32, no. 09 (2021): 2150117. http://dx.doi.org/10.1142/s0129183121501175.

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The application of a flapping wing mechanism offers a vast range of development possibilities for unmanned aerial vehicles (UAVs) and autonomous underwater vehicles (AUVs). The influence of wake transitions on flapping wing mechanism’s capabilities is not fully understood particularly at low Reynolds numbers. The numerical investigation of a symmetric airfoil performing sinusoidal heaving oscillations is performed to explore the wake transitions. The influence of heaving parameters on wake transitions when exposed to a constant velocity flow is investigated. The existence of reverse von Karman vortex street, deflected wake and chaotic wake is observed. The wake deflection is found to switch its direction before transforming into a chaotic wake. The coherent structures and its evolution with the flow are presented using proper orthogonal decomposition (POD). The underlying structures and their interactions for different wake situations are identified. Correlations for the nondimensional maximum velocity in the wake in terms of frequency and amplitude is proposed. The wake dynamics is found to depend significantly on the leading edge vortices. The time-varying velocity fluctuations in the flow field are presented and discussed in detail. The velocity fluctuation contours are used to identify the regions of momentum transfer. The transient nature of the flow field is studied using the phase plot. A transition route from the periodic to chaotic regime though a quasi-periodic regime is established using time series analysis. The wake transitions are observed to be more sensitive towards heaving frequency than the heaving amplitude.

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Zhang, Yu-xin, Xiao-ping Wu, Zhi-yong Zhou, Xuan-kai Cheng, and Yu-long Li. "A numerical study on the interaction between forward and aft propellers of hybrid CRP pod propulsion systems." Ocean Engineering 186 (August 2019): 106084. http://dx.doi.org/10.1016/j.oceaneng.2019.05.066.

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Zhang, Yuxin, Xuankai Cheng, and Liang Feng. "Numerical investigation of the unsteady flow of a hybrid CRP pod propulsion system at behind-hull condition." International Journal of Naval Architecture and Ocean Engineering 12 (2020): 918–27. http://dx.doi.org/10.1016/j.ijnaoe.2020.10.003.

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Wang, Wei, Dagang Zhao, Chunyu Guo, and Yongjie Pang. "Analysis of Hydrodynamic Performance of L-Type Podded Propulsion with Oblique Flow Angle." Journal of Marine Science and Engineering 7, no. 2 (2019): 51. http://dx.doi.org/10.3390/jmse7020051.

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In this study, the Reynolds-averaged Navier–Stokes (RANS) method and a model experimental test in a towing tank are used to investigate the unsteady hydrodynamic performance of L-type podded propulsion under different oblique flow angles and advance coefficients. The results show that the load of the operative propeller increases with oblique flow angle and the bracket adds resistance to the pod due to the impact of water flow, leading to a reduced propeller thrust coefficient with increased oblique flow angle. Under a high advance coefficient, the speed of increase of the pressure effect is higher than that of the viscosity effect, and the propeller efficiency increases with the oblique flow angle. The nonuniformity of the inflow results in varying degrees of asymmetry in the horizontal and vertical distributions of the propeller blade pressure. Under high oblique flow angle, relatively strong interference effects are seen between venting vortexes and the cabin after blades, leading to a disorderly venting vortex system after the blade. The numerical simulation results are in good agreement with the experimental values. The study findings provide a foundation for further research on L-type podded propulsors.

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Ahmed, Shoaib, Tie Li, Shuai Huang, and Jiale Cao. "Dynamic and quantitative risk assessment of Cruise ship pod propulsion system failure: An integrated Type-2 Fuzzy-Bayesian approach." Ocean Engineering 279 (July 2023): 114601. http://dx.doi.org/10.1016/j.oceaneng.2023.114601.

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Nargi, Ranieri Emanuele, Paolo Candeloro, Fabrizio De Gregorio, Giuseppe Ceglia, and Tiziano Pagliaroli. "Fluid-Dynamic and Aeroacoustic Characterization of Side-by-Side Rotor Interaction." Aerospace 10, no. 10 (2023): 851. http://dx.doi.org/10.3390/aerospace10100851.

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An investigation of twin corotating rotors’ interaction effects was performed by load (thrust and torque) measurements, flow field dynamics through Time-Resolved Particle Image Velocimetry, and acoustic emissions using a microphone array. Two rotors, each with a diameter of D = 393.7 mm and equipped with three blades, were investigated in a side-by-side configuration, to simulate a multirotor propulsion system. The mutual distance between the propellers is 1.02 D, and four different rotating speeds, i.e., 2620, 3500, 4360, and 5200 RPM, were explored. In such a configuration, thrust and torque undergo a reduction compared to that found for a single propeller configuration. The level of aerodynamic load fluctuations increases as well. The interaction of the wakes produces a recirculation region at the external periphery of the shear layers. An innovative approach involving the coupling of Proper Orthogonal Decomposition (POD) and Wavelet Transform has been employed to investigate the dominant structures within the flow and their mutual influence. The results reveal that the interacting wakes are dominated by a wave-like motion pulsating at Harmonics of the Blade Passing Frequency (HBPF) of 1/3. Higher orders of POD modes capture coherent vortical structures, including tip vortices pulsating at HBPF = 1. The aeroacoustic investigation shows that the noise level, in terms of the Over All Sound Pressure Level, presents a remarkable increment concerning that generated by the single propeller.

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Xiong, Ying, Ke Zhang, Zhan-zhi Wang, and Wan-jiang Qi. "Numerical and experimental studies on the effect of axial spacing on hydrodynamic performance of the hybrid CRP pod propulsion system." China Ocean Engineering 30, no. 4 (2016): 627–36. http://dx.doi.org/10.1007/s13344-016-0040-8.

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Aitakkache, Mourad, Philippe Enrici, Daniel Matt, Nadhem Boubaker, and Lorenzo Piscini. "Concept, Feasibility of Cylindrical Bar Winding for Low Voltage Permanent Magnet Synchronous Motor." Energies 15, no. 4 (2022): 1507. http://dx.doi.org/10.3390/en15041507.

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In this paper, we present the use of a solid bar winding for a permanent magnet synchronous motor dedicated to the electric drive of a full electric boat. For the winding, we chose to use cylindrical bars for the electric vehicle motorizations of a power lower than 10 kW. The choice of a 60 VDC low-voltage power distribution requires resorting to a solid bar winding with one bar per slot (single turn). Hence, the solid conductors dissipate additional copper losses (higher AC resistance). An analysis of these additional copper losses was carried out to accurately assess the effective AC resistance of the winding and, hence, the efficiency of the electric motor. A prototype for a POD propulsion was designed, built and tested. The characteristics of its electric motor were presented. The feasibility this type of cylindrical bar winding has been proven. A study on the optimization of the slot has demonstrated the performance of this type of winding.

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HERMOSILLA FERNANDEZ, CARLOS, and TERESA MAGAL ROYO. "USER EXPERIENCE REQUIREMENTS FOR HYPERLOOP PASSENGER’S CABIN." DYNA 97, no. 4 (2022): 386–91. http://dx.doi.org/10.6036/10480.

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Although Hyperloop technology is still in its early stages, its technical and economic potential will become a revolution in the transport industry in Europe that will serve to unify it. The development of Hyperloop technology should focus on improving propulsion technology issues and keep an eye on the human and perceptual aspects during the traveling, which could be a key factor when engineers develop the passenger cabins and implement advanced prototypes to market. Regarding the user experience will serve in the future to create and develop an interior design for the Hyperloop cabin that adapts to the sensory stimulation features and practical needs of the user during the journey. The synergy between the Hyperloop technology and the traveler experience will help as a bridge for the citizens of the future who use this new type of transport with confidence. The article aims to analyze the most critical aspects used to evaluate future transport through user experience methodologies. That should be considered a fundamental part of the interior space design of the cabin through common areas and specific services. It describes two essential aspects in the design of future Hyperloop cabins or pods. On the one hand, the user experience methodologies related to the perception of comfort and safety in this new transport allow evaluation of the expectations in its use in the future. On the other hand, the description of the cognitive factors that influence the interior cabins' design affects the development of future devices such as passengers' seats in the pod. Keywords: Hyperloop, user experience, passenger pod, taxonomy, neurodesign, user-centered design, interaction

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Jin, Biao, Yuqiang Li, Kecai Jiang, Zhulian Li, and Shanshan Chen. "GRACE-FO Antenna Phase Center Modeling and Precise Orbit Determination with Single Receiver Ambiguity Resolution." Remote Sensing 13, no. 21 (2021): 4204. http://dx.doi.org/10.3390/rs13214204.

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Precise knowledge of the phase center location of the global navigation satellite system (GNSS) antenna is a prerequisite for precise orbit determination (POD) of the low Earth orbit (LEO) satellite. The phase center offset (PCO) and phase center variation (PCV) values for the LEO antenna obtained from ground calibration cannot reflect the error sources encountered in the actual spacecraft environment. PCV corrections are estimated by ionosphere free (IF) carrier phase post-fit residuals of reduced dynamic orbit determination. Ambiguity resolution (AR) plays a crucial role in achieving the best orbit accuracy. The single receiver AR concept is realized using wide-lane (WL) and narrow-lane (NL) bias products. Single difference (SD) observations between satellites are applied to remove the receiver dependent phase bias. SD AR and traditional double difference (DD) AR methods are applied to fix the ambiguities. The recovered SD and DD IF ambiguities are taken as pseudo-observations to constrain the undifferenced IF ambiguity parameters in the POD process. The LEO orbits based on float ambiguity (FA), SD, AR, and DD AR are investigated. One year’s data collected by the Gravity Recovery And Climate Experiment Follow-On (GRACE-FO) mission and GPS precise products provided by the Center for Orbit Determination in Europe (CODE) were analyzed. Precise orbit generated by the Jet Propulsion Laboratory (JPL), independent satellite laser ranging (SLR), and K-band ranging (KBR) measurements were utilized to assess the orbit accuracy. More than 98% of SD WL and 95% of SD NL ambiguities are fixed, which confirms the good quality of the bias products and correctness of the SD AR method. With PCV corrections, the average phase residuals of DD and SD AR solutions are 0.13 and 0.41 mm, which indicates improved consistency between applied models and observations. Compared with JPL’s orbit, the SD AR orbits achieve the accuracy of 6.0, 6.2, and 5.1 mm in along-track, cross-track, and radial directions. The SD AR solutions show an average improvement of 18.3% related to the FA orbits while 6.3% is gained by the DD AR approach. The root mean squares (RMSs) of SLR residuals for FA, DD AR, and SD AR solutions are 11.5, 10.2, and 9.6 mm, which validate the positive effect of AR on POD. Standard deviation (STD) of KBR residuals for SD AR orbits is 1.8 mm while 0.9 mm is achieved by the DD AR method. The explanation is that the phase bias products used for SD AR are not free of errors and the errors may degrade the KBR validation. In-flight PCV calibration and ambiguity resolution improve the LEO orbit accuracy effectively.

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BOZKURTTAS, M., R. MITTAL, H. DONG, G. V. LAUDER, and P. MADDEN. "Low-dimensional models and performance scaling of a highly deformable fish pectoral fin." Journal of Fluid Mechanics 631 (July 17, 2009): 311–42. http://dx.doi.org/10.1017/s0022112009007046.

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The hydrodynamics of a highly deformable fish pectoral fin used by a bluegill sunfish (Lepomis macrochirus) during steady forward swimming are examined in detail. Low-dimensional models of the fin gait based on proper orthogonal decomposition (POD) are developed, and these are subjected to analysis using an incompressible Navier–Stokes flow solver. The approach adopted here is primarily motivated by the quest to develop insights into the fin function and associated hydrodynamics, which are specifically useful for the design of a biomimetic, pectoral fin propulsor. The POD analysis shows that the complex kinematics of the pectoral fin can be described by a few (<5) POD modes and that the first three POD modes are highly distinct. The significance of these modes for thrust production is examined by synthesizing a sequence of fin gaits from these modes and simulating the flow associated with these gaits. We also conduct a scale study of the pectoral fin in order to understand the effect of the two key non-dimensional parameters, Reynolds number and Strouhal number, on the propulsive performance. The implications of the POD analysis and performance scaling on the design of a robotic pectoral fin are discussed.

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Liu, Qingyun, Yiwen Zha, Tao Liu, and Chao Lu. "Research on Adaptive Control of Air-Borne Bolting Rigs Based on Genetic Algorithm Optimization." Machines 9, no. 10 (2021): 240. http://dx.doi.org/10.3390/machines9100240.

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Rotation speed and propulsive force are the two critical parameters in the work of the air-borne bolting rig. To address the problem that unreasonable rotation speed and propulsive force will induce the breakage of the drill pipe and the inability of the drill bit to cut coal adequately this paper proposes an adaptive control strategy for the air-borne bolting rig based on genetic algorithm optimization. Firstly, we obtain the corresponding coal hardness by the real-time acquisition of the working torque of the drill pipe. Then we calculate the reasonable rotation speed of the hydraulic motor and the propulsive force of the hydraulic cylinder on the coal of different hardness. Secondly, the genetic algorithm is applied to optimize the parameters of the PID (proportion integration differentiation) controller so that the system may attain the target value fast and reliably and achieve adaptive control. Finally, a simulation model of the slewing system and the propulsion system of the air-borne bolting rig are established in the AMESim hydraulic software, and the simulation tests were carried out under two distinct working conditions: single coal hardness and coal hardness of sudden change. The results indicate that the PID control strategy based on genetic algorithm optimization has a shorter response time, a smaller overshoot, and a lower steady-state error than the traditional PID control strategy.

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Islam, Mohammed F., Brian Veitch, Pengfei Liu, and Ayhan Akinturk. "Gap Effect on Performance of Podded Propulsors in Straight-Ahead and Azimuthing Conditions." Marine Technology and SNAME News 47, no. 01 (2010): 47–58. http://dx.doi.org/10.5957/mtsn.2010.47.1.47.

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This paper presents results of an experimental study on the effect of gap distance on propulsive characteristics of puller and pusher podded propulsors in straight-ahead and static azimuthing open-water conditions. The gap distance is the axial distance between the rotating (propeller) and stationary (pod) parts of a podded propulsor. The propeller thrust and torque, unit forces, and moments in the three-coordinate directions of a model podded unit were measured using a custom-designed pod dynamometer in various operating conditions. The model propulsor was tested at the gap distances of 0.3%, 1%, and 2% of propeller diameter for a range of advance coefficients combined with the range of static azimuthing angles from +20_ to 20_ with a 10_ increment. The tests were conducted both in puller and pusher configurations in the same loading and azimuthing conditions. In the puller configuration, the gap distance did not have any noticeable effect on propeller torque in straight course condition, but had an effect in azimuthing conditions. The propeller thrust and efficiency were also influenced by the change of gap distance, and the effects were more pronounced at high azimuthing angles and high advance coefficients. For pusher configuration, however, the gap distance did not affect the propeller performance characteristics in straight-ahead and azimuthing conditions. Both in straight course and azimuthing conditions, the unit thrust and efficiency were not influenced by the gap distance in either puller or pusher configurations. The gap distance had a noticeable effect on unit transverse force and steering moment both in puller and pusher configurations, and both in straight course

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Zhang, Lei, Chuanshun Du, Yongsen Ni, Yuchen Shang, and Jianing Zhang. "Mechanism of Speed Loss Reduction and Propulsion Efficiency Improvement of ONR Tumblehome with Active-Controlled Stern Flaps in Resonance Waves." Journal of Marine Science and Engineering 12, no. 5 (2024): 822. http://dx.doi.org/10.3390/jmse12050822.

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The stern flap is a practical hull appendage equipment that enhances ship navigation performance and saves energy. The existing studies mainly focus on the fixed stern flap, other than an actively controlled one, so it is worth further exploring its effect and mechanism. By implanting the PID controller to the stern flap, this paper proposed a free-running CFD model on the ONRT (the Office of Naval Research Tumblehome) ship coupled with the active-controlled stern flap to investigate the hydrodynamic performance in resonance waves. The free-running performance in calm water and regular waves is numerically researched and verified versus the experimental and referenced results. Then, the effect of different PID coefficients and control strategies of the stern flap on the traveling speed, attitudes, and propulsion performance under the resonance wave condition is conducted, and the influence mechanism is explored. The results show that adopting a fixed flap controller and PID controller can reduce the original speed loss by 4.2% and 6.9%, respectively, and increase the average propulsive efficiency of the propeller by 1.0% and 1.4%, respectively. Further analysis reveals that the global effect of the suppressed motion attitudes due to the installation of the fixed flap effectively contributes to the resistance reduction. However, the local effect of the stern flap increases the resistance due to interaction with the propeller and stern. The PID-controlled stern flap exhibits similar average attitudes compared to the fixed one, which means the resistance reduction of the global effect is kept the same, and the active stern flap further improves the stern flow field, where the resistance increment of the local effect is weakened, enhancing the traveling speed and improving the propulsion efficiency.

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Zhang, Xuelin, Xiaobin Xu, Xiaojian Xu, Pingzhi Hou, Haibo Gao, and Feng Ma. "Intelligent Adaptive PID Control for the Shaft Speed of a Marine Electric Propulsion System Based on the Evidential Reasoning Rule." Mathematics 11, no. 5 (2023): 1145. http://dx.doi.org/10.3390/math11051145.

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To precisely and timely control the shaft speed for a marine electric propulsion system under normal sea conditions, a new shaft speed control technique combining the evidential reasoning rule with the traditional PID controller was proposed in this study. First, an intelligent adaptive PID controller based on the evidential reasoning rule was designed for a marine electric propulsion system to obtain the PID parameters KP, KI, and KD. Then, a local iterative optimization strategy for model parameters was proposed. Furthermore, the parameters of the adaptive PID controller model were optimized in real time by using the sequential linear programming algorithm, which enabled the adaptive adjustment of KP, KI, and KD. Finally, the performance of the adaptive PID controller regarding the shaft speed control was compared with that of other controllers. The results showed that the adaptive PID controller designed in this study had better control performance, and the shaft speed control method based on the adaptive PID controller could better control the shaft speed of the marine electric propulsion system.

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Bian, Li, Xiangqian Che, Liu Chengyang, Dai Jiageng, and He Hui. "Parameter optimization of unmanned surface vessel propulsion motor based on BAS-PSO." International Journal of Advanced Robotic Systems 19, no. 2 (2022): 172988142110406. http://dx.doi.org/10.1177/17298814211040688.

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Despite advances in modern control theory and artificial intelligence technology, current methods for tuning proportional-integral-derivative (PID) controller parameters based on the traditional particle swarm optimization (PSO) algorithm do not meet the requirements for controlling an unmanned surface vessel (USV) propulsion motor. To overcome the disadvantages of the PSO algorithm, such as low precision and easily falling into a local optimum, the beetle antennae search (BAS) algorithm can be introduced into the PSO algorithm by replacing particles with beetles, and effectively prevents the PSO algorithm from easily falling into the local optimum. At the same time, the BAS algorithm will no longer be limited to single objective parameterization. Herein, we propose a PID parameter optimization method based on the hybrid BAS-PSO algorithm for a USV propulsion motor. The PID parameter optimization of propulsion motor effectively becomes a beetle foraging problem with group optimization. Numerical results show that the method can effectively solve the problems of PSO and greatly improve convergence speed. Compared with the genetic algorithm and standard PSO algorithm, the BAS-PSO algorithm is superior for PID parameter tuning and can improve performance of USV propulsion system.

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Li, Yuanzhou, Zhong Liu, Zhonggang Xiong, Zhong Chen, and Jinyun Cai. "Research on PID Control Strategy of Power Head Propulsion System of Engineering Hydraulic Drilling Rig." Journal of Physics: Conference Series 2483, no. 1 (2023): 012043. http://dx.doi.org/10.1088/1742-6596/2483/1/012043.

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Abstract A mechanical model of the synchronous hydraulic system of the propulsion mechanism is established by taking the power head propulsion system of an engineering hydraulic drilling rig as the research subject. A master-slave regulation method based on the PID control strategy is proposed for the displacement deviation of two synchronous cylinders under the disturbance of external force. The method controls the synchronous accuracy of the two propulsion cylinders. Joint modeling and simulation with AMEsim and MATLAB are used to investigate the control performance of this synchronously controlled hydraulic cylinder under the disturbance of external forces. The results show that the system is subjected to an external load and cylinder 1 stabilizes after t=0.17s, and the synchronous control error between cylinder 1 and the expected value is 0.0005m. The stabilization error between cylinder 2 and cylinder 1 is 0.0006m; the power head propulsion system achieves the accuracy required for engineering construction and meets the working requirements of the engineering hydraulics drilling rig for the power head propulsion system.

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Reichel, Maciej. "Manoeuvring forces on azimuthing podded propulsor model." Polish Maritime Research 14, no. 2 (2007): 3–8. http://dx.doi.org/10.2478/v10012-007-0006-0.

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Manoeuvring forces on azimuthing podded propulsor model This paper presents the preliminary part of comprehensive manoeuvring open-water tests of a gas carrier model. The paper focuses on open water experiments with an azimuthing podded propulsor. The test program was carried out in the cavitation tunnel and the large towing tank of Ship Hydromechanics Division, Ship Design and Research Centre, Gdańsk. The pod was tested as a pushing unit with a 161.3 mm diameter propeller. Steering forces were measured in the range of advance coefficient from 0.0 to 0.8 combined with the range of deflection angles from -45° up to +45°. Measurements on the pod without propeller were also performed. The experiment results are presented in the form of non-dimensional coefficients in function of advance coefficient and deflection angle. Analysis of the experimental results and the conclusions are presented.

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Youssef, Andrew, David Matthews, Andrew Guzzomi, and Jie Pan. "Contact Force Measurement in an Operational Thrust Bearing using PVDF Film at the Blade and Pad Passing Frequencies." Sensors 18, no. 11 (2018): 3956. http://dx.doi.org/10.3390/s18113956.

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A major contributor to longitudinal vibration in marine propulsion systems is propeller induced excitation. This constitutes a key source of underwater acoustical radiation through excitation of the hull. Understanding this hydrodynamic force at the interface of the thrust bearing is important in order to develop an accurate vibrational model of the propulsion system and in determining potential control mechanisms. In order to investigate the thrust force during operation of a propulsion system, Polyvinylidene Fluoride (PVDF) was embedded into the stationery collar inside a custom thrust bearing in a scaled model of a typical propulsion system. The number of blades of the propeller and its rotational speed were altered to obtain an understanding of the characteristic vibrations of the shaft propulsion system. The rig comprised of the propeller, shaft, journal bearings and a thrust bearing. A two and three blade propeller and a four, five and six pad bearing were tested. A strain gauge and accelerometer were used to infer the propeller force and enable comparison with the PVDF signals. As a result of the asymmetrical flow around the propeller, the blade passing frequencies (BPF) are clearly observed. This frequency contribution was present at all speeds tested. The PVDF signal also showed significant pad passing frequency (PPF) and BPF and modulation of both.

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Li, Sinan, Li Zhang, Jingfeng Xiao, Rui Ma, Xiangjun Tian, and Min Yan. "Simulating carbon and water fluxes using a coupled process-based terrestrial biosphere model and joint assimilation of leaf area index and surface soil moisture." Hydrology and Earth System Sciences 26, no. 24 (2022): 6311–37. http://dx.doi.org/10.5194/hess-26-6311-2022.

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Abstract. Reliable modeling of carbon and water fluxes is essential for understanding the terrestrial carbon and water cycles and informing policy strategies aimed at constraining carbon emissions and improving water use efficiency. We designed an assimilation framework (LPJ-Vegetation and soil moisture Joint Assimilation, or LPJ-VSJA) to improve gross primary production (GPP) and evapotranspiration (ET) estimates globally. The integrated model, LPJ-PM (LPJ-PT-JPLSM Model) as the underlying model, was coupled from the Lund–Potsdam–Jena Dynamic Global Vegetation Model (LPJ-DGVM version 3.01) and a hydrology module (i.e., the updated Priestley–Taylor Jet Propulsion Laboratory model, PT-JPLSM). Satellite-based soil moisture products derived from the Soil Moisture and Ocean Salinity (SMOS) and Soil Moisture Active and Passive (SMAP) and leaf area index (LAI) from the Global LAnd and Surface Satellite (GLASS) product were assimilated into LPJ-PM to improve GPP and ET simulations using a proper orthogonal decomposition (POD)-based ensemble four-dimensional variational assimilation method (PODEn4DVar). The joint assimilation framework LPJ-VSJA achieved the best model performance (with an R2 ( coefficient of determination) of 0.91 and 0.81 and an ubRMSD (unbiased root mean square deviation) reduced by 40.3 % and 29.9 % for GPP and ET, respectively, compared with those of LPJ-DGVM at the monthly scale). The GPP and ET resulting from the assimilation demonstrated a better performance in the arid and semi-arid regions (GPP: R2 = 0.73, ubRMSD = 1.05 g C m−2 d−1; ET: R2 = 0.73, ubRMSD = 0.61 mm d−1) than in the humid and sub-dry humid regions (GPP: R2 = 0.61, ubRMSD = 1.23 g C m−2 d−1; ET: R2 = 0.66; ubRMSD = 0.67 mm d−1). The ET simulated by LPJ-PM that assimilated SMAP or SMOS data had a slight difference, and the SMAP soil moisture data performed better than SMOS data. Our global simulation modeled by LPJ-VSJA was compared with several global GPP and ET products (e.g., GLASS GPP, GOSIF GPP, GLDAS ET, and GLEAM ET) using the triple collocation (TC) method. Our products, especially ET, exhibited advantages in the overall error distribution (estimated error (μ): 3.4 mm per month; estimated standard deviation of μ: 1.91 mm per month). Our research showed that the assimilation of multiple datasets could reduce model uncertainties, while the model performance differed across regions and plant functional types. Our assimilation framework (LPJ-VSJA) can improve the model simulation performance of daily GPP and ET globally, especially in water-limited regions.

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Ren, Ziqiang, Feng Zhou, Hai Zhu, et al. "Analysis and Research on Mobile Drilling Rig for Deep Seabed Shallow Strata." Marine Technology Society Journal 55, no. 2 (2021): 81–93. http://dx.doi.org/10.4031/mtsj.55.2.7.

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Abstract Drilling rigs for deep seabed shallow strata are commonly used to explore ocean cobalt-rich crust resources and other fields. This paper mainly presents the structure and mechanism of a mobile drilling rig for use in acquiring seafloor cores that are up to 1.5 m in length. The software Simcenter Amesim is used to establish the mobile drilling rig's hydraulic propulsion system model, which is the basis and a core part of the rig. Moreover, closed-loop and PID (proportion-integral-differential) control methods are separately used to control the hydraulic propulsion system for simulation analysis. Comparison of the simulation results shows that the PID control method is more convincing in verifying the design rationality of the hydraulic propulsion system. In the simulation of the PID-controlled hydraulic propulsion system, the co-simulation technology of Simcenter Amesim and MATLAB/Simulink not only establishes the hydraulic and control models but also determines the relevant simulation parameters, thereby helping improve system simulation efficiency. In its verification deployment in the South China Sea, the mobile drilling rig has been operated many times at different depths, and some cores have been successfully obtained. It was also used during the 55th Voyage of China Oceanic Scientific Expedition, which was supported by the China Ocean Mineral Resources R&D Association. Several sites were explored, and a large number of cobalt-rich crust cores were obtained. Theory and sea trials are explained to support further research on the survey of abyssal resources.

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Song, Dalei, Lin Li, Changbin Wang, Renyu Hou, and Chong Li. "A practical robust yaw servo architecture of ROVs by multi-vector propulsion and nonlinear controller." Transactions of the Institute of Measurement and Control 42, no. 15 (2020): 2908–18. http://dx.doi.org/10.1177/0142331220932373.

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Multi-vector arrangement is a novel propulsion architecture for remotely operated vehicles (ROV) because of its high manoeuvrability and efficiency, but the influence on the ROV dynamics and attitude servo control has not yet been clearly evaluated. This study fully investigated the kinematic behaviours of a hexagonal multi-vector propulsion ROV with communication delay constraint and reduced the complex model for precision control system design. An enhanced model-based PI robust controller (EMPRC) based on the nominal model is proposed to solve the nonlinear hydrodynamics and communication problems with high performance yaw control, whose stability is also analysed. The conventional proportional-integral-derivative (PID) and integral separation PID are used in the experiments for comparison. The results indicate that the proposed EMPRC can effectively track the desired attitude and reject the external disturbances, while the conventional ones are limited by the nonlinear dynamics and communication delays. The improvement is 3x on average in terms of overshoot, settling time and anti-disturbance recovery time compared to conventional algorithms and proves this proposed novel EMPRC is a practical solution for multi-vector propulsion ROVs.

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Toro Salazar, C., C. Rinaldi, and M. L. Azcárate. "IMPLEMENTATION OF A NOMARSKY INTERFEROMETER FOR THE CHARACTERIZATION OF ABLATIVE LASER PROPULSION PROCESSES." Anales AFA 29, no. 1 (2018): 8–11. http://dx.doi.org/10.31527/anafa_2018/29_8.

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Toro, C., C. Rinaldi, and M. L. Azcárate. "IMPLEMENTATION OF A NOMARSKY INTERFEROMETER FOR THE CHARACTERIZATION OF ABLATIVE LASER PROPULSION PROCESSES." Anales AFA 29, no. 1 (2018): 8–11. http://dx.doi.org/10.31527/analesafa.2018.29.1.8.

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Chang, Bong-Jun, and Seokcheon Go. "Study on a procedure for propulsive performance prediction for CRP-POD systems." Journal of Marine Science and Technology 16, no. 1 (2010): 1–7. http://dx.doi.org/10.1007/s00773-010-0108-8.

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