Pub Date : 2024-09-19DOI: 10.1177/14750902241272797
Nan Pang, Kai Xu, Feihong Yun, Xiangyu Wang, Zhong Liu, Zhonggang Xiong
In the ocean engineering environment, the quality failure data of complex systems are difficult to obtain due to the high experiment cost. In addition, using a single model to analyze risk, reliability, availability, and maintainability is a big challenge. Based on the fault tree, Dynamic Bayes and Markov models, a state assessment method for ocean engineering systems with multiple maintenance modes is proposed in this paper. This method gives full play to the advantages of the three methods, and comprehensively analyzes the risk, reliability, availability and maintainability. This method uses fault tree and Markov model to pre-process fault data, and then inputs the pre-processed fault data into the multi-state degradation model based on dynamic Bayesian theory. Considering the maintenance strategies of no repair, perfect repair, imperfect repair and preventive repair, the model is iterated and adjusted until the model has processed all the event data and the updated model can best reflect the state of the system. The method is verified by taking the subsea tree of the subsea production system as an example. The obtained tree reliability index (mean time without failure) is basically consistent with the failure statistics of offshore and onshore reliability databases, which verifies the accuracy of the proposed method.
{"title":"A grouping module assessment method for ocean engineering systems: Subsea tree system as a case","authors":"Nan Pang, Kai Xu, Feihong Yun, Xiangyu Wang, Zhong Liu, Zhonggang Xiong","doi":"10.1177/14750902241272797","DOIUrl":"https://doi.org/10.1177/14750902241272797","url":null,"abstract":"In the ocean engineering environment, the quality failure data of complex systems are difficult to obtain due to the high experiment cost. In addition, using a single model to analyze risk, reliability, availability, and maintainability is a big challenge. Based on the fault tree, Dynamic Bayes and Markov models, a state assessment method for ocean engineering systems with multiple maintenance modes is proposed in this paper. This method gives full play to the advantages of the three methods, and comprehensively analyzes the risk, reliability, availability and maintainability. This method uses fault tree and Markov model to pre-process fault data, and then inputs the pre-processed fault data into the multi-state degradation model based on dynamic Bayesian theory. Considering the maintenance strategies of no repair, perfect repair, imperfect repair and preventive repair, the model is iterated and adjusted until the model has processed all the event data and the updated model can best reflect the state of the system. The method is verified by taking the subsea tree of the subsea production system as an example. The obtained tree reliability index (mean time without failure) is basically consistent with the failure statistics of offshore and onshore reliability databases, which verifies the accuracy of the proposed method.","PeriodicalId":20667,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment","volume":"21 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The paper integrates the modal avoidance method, pedestal design method, and dynamic vibration absorber theory to investigate vibration control technology for offshore platform plate structures. We develop an integrated design method for vibration suppression by controlling the vibration excitation load, vibration transmission, and vibration energy dissipation. Firstly, a modal avoidance design is implemented to suppress vibration transmission along the propagation path of the plate structure. Subsequently, pedestal optimization is conducted for pedestal structure to attenuate vibration excitation at the input end. Finally, dynamic vibration absorber theory is employed to control dominant vibration frequency responses further and achieve multi-target vibration control. Case simulation results demonstrate that the integrated design method reduces the acceleration vibrations level at 113.75, 145.61, and 153 Hz, and this method could guide multi-objective vibration control in offshore platform plate structures.
{"title":"Integrated design method for protection against vibration of offshore platform plate structure","authors":"Ziwei Deng, Xuchen Jia, Zijian Li, Xu Sun, Fuzhen Pang, Baocheng Zhang","doi":"10.1177/14750902241271865","DOIUrl":"https://doi.org/10.1177/14750902241271865","url":null,"abstract":"The paper integrates the modal avoidance method, pedestal design method, and dynamic vibration absorber theory to investigate vibration control technology for offshore platform plate structures. We develop an integrated design method for vibration suppression by controlling the vibration excitation load, vibration transmission, and vibration energy dissipation. Firstly, a modal avoidance design is implemented to suppress vibration transmission along the propagation path of the plate structure. Subsequently, pedestal optimization is conducted for pedestal structure to attenuate vibration excitation at the input end. Finally, dynamic vibration absorber theory is employed to control dominant vibration frequency responses further and achieve multi-target vibration control. Case simulation results demonstrate that the integrated design method reduces the acceleration vibrations level at 113.75, 145.61, and 153 Hz, and this method could guide multi-objective vibration control in offshore platform plate structures.","PeriodicalId":20667,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment","volume":"118 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-15DOI: 10.1177/14750902241272880
Min-Hyeok Kim, Suk-Yoon Hong, Jee-Hun Song
A pump-jet propeller is composed of a rotor, stator, and duct. A pre-swirl stator is employed to optimize flow into the rotor. The hydrodynamic and noise performances of pump-jet propellers vary with the stator angles. In this study, the hydrodynamic performance of a full-scale submarine and pump-jet propeller is assessed by conducting computational fluid dynamics simulations based on the Reynolds-averaged Navier–Stokes equation. Additionally, broadband noise, blade-passing frequency noise, and a significant factor, that is, underwater radiated noise are predicted using Lighthill’s equation, Green’s function, and wall pressure spectrum. Unsteady forces were extracted from the flow field to obtain the blade-passing frequency noise. Broadband noise could not be calculated directly from the flow field owing to the absence of small eddies, and wall pressure spectrum was used to obtain high-frequency broadband noise. The overall noise, including broadband noise and blade-passing frequency noise, was evaluated. The optimal stator angle for the rotor at the self-propulsion point was determined considering the propulsion efficiency and noise level of the pump-jet propeller.
{"title":"Effect of pre-swirl stator angles on broadband noise considering hydrodynamic performance of pump-jet propeller","authors":"Min-Hyeok Kim, Suk-Yoon Hong, Jee-Hun Song","doi":"10.1177/14750902241272880","DOIUrl":"https://doi.org/10.1177/14750902241272880","url":null,"abstract":"A pump-jet propeller is composed of a rotor, stator, and duct. A pre-swirl stator is employed to optimize flow into the rotor. The hydrodynamic and noise performances of pump-jet propellers vary with the stator angles. In this study, the hydrodynamic performance of a full-scale submarine and pump-jet propeller is assessed by conducting computational fluid dynamics simulations based on the Reynolds-averaged Navier–Stokes equation. Additionally, broadband noise, blade-passing frequency noise, and a significant factor, that is, underwater radiated noise are predicted using Lighthill’s equation, Green’s function, and wall pressure spectrum. Unsteady forces were extracted from the flow field to obtain the blade-passing frequency noise. Broadband noise could not be calculated directly from the flow field owing to the absence of small eddies, and wall pressure spectrum was used to obtain high-frequency broadband noise. The overall noise, including broadband noise and blade-passing frequency noise, was evaluated. The optimal stator angle for the rotor at the self-propulsion point was determined considering the propulsion efficiency and noise level of the pump-jet propeller.","PeriodicalId":20667,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment","volume":"19 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-14DOI: 10.1177/14750902241273992
Mehmet Akman
Gulet-type yachts are one of the symbols of maritime culture with their unique hull forms and schooner or ketch-type riggings. In parallel with the targets aiming for decarbonization in the maritime industry, energy efficiency and emission control are on the agenda for these types of yachts. Driven by this motivation, a novel benchmark study for the gulet-type yachts is conducted to evaluate the energy efficiency and environmental impacts associated with the adoption of LNG or methanol as primary fuel alternatives to MDO. The benchmark study is constructed in two steps: Presenting the design and propulsion characteristics of existing gulets, followed by a detailed analysis of the energy efficiency and environmental impacts of using alternative fuels. Therefore, 57 gulets with round and transom sterns whose hull forms are analyzed, modeled and general characteristics are presented. After modeling, the resistance and effective power of hull forms are predicted using the Holtrop-Mennen method and CFD. The flow characteristics around the hulls are obtained and the results are validated using the previous experimental studies in the first step. Then, installed and computed engine capacities are compared, and the Annual Emission Ratio and Energy Efficiency Index (EEI) are calculated for environmental impact assessments. Finally, the applicability of using LNG or MeOH-fueled propulsion systems for gulet-type yachts is discussed considering energy efficiency and design. According to the results, transitioning to alternative fuels can increase the Energy Efficiency Index of gulet-type yachts by over 20%.
{"title":"A benchmark study on the energy efficiency and environmental impacts of alternative fuels in gulet-type sailing yachts","authors":"Mehmet Akman","doi":"10.1177/14750902241273992","DOIUrl":"https://doi.org/10.1177/14750902241273992","url":null,"abstract":"Gulet-type yachts are one of the symbols of maritime culture with their unique hull forms and schooner or ketch-type riggings. In parallel with the targets aiming for decarbonization in the maritime industry, energy efficiency and emission control are on the agenda for these types of yachts. Driven by this motivation, a novel benchmark study for the gulet-type yachts is conducted to evaluate the energy efficiency and environmental impacts associated with the adoption of LNG or methanol as primary fuel alternatives to MDO. The benchmark study is constructed in two steps: Presenting the design and propulsion characteristics of existing gulets, followed by a detailed analysis of the energy efficiency and environmental impacts of using alternative fuels. Therefore, 57 gulets with round and transom sterns whose hull forms are analyzed, modeled and general characteristics are presented. After modeling, the resistance and effective power of hull forms are predicted using the Holtrop-Mennen method and CFD. The flow characteristics around the hulls are obtained and the results are validated using the previous experimental studies in the first step. Then, installed and computed engine capacities are compared, and the Annual Emission Ratio and Energy Efficiency Index (EEI) are calculated for environmental impact assessments. Finally, the applicability of using LNG or MeOH-fueled propulsion systems for gulet-type yachts is discussed considering energy efficiency and design. According to the results, transitioning to alternative fuels can increase the Energy Efficiency Index of gulet-type yachts by over 20%.","PeriodicalId":20667,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-14DOI: 10.1177/14750902241272778
Wu Chengkun, Zhifeng Zhu, Cai Bohua, Yao Yong
Based on the RANS method using unstructured grids, numerical simulations of cavitation on the DTMB propeller under uniform inflow conditions were conducted. Through numerical studies of pressure pulsations under different cavitation numbers, it was found that at low cavitation numbers, the pressure fluctuations become irregular with higher amplitude and increased noise. As the cavitation number increases, the pressure tends to stabilize and exhibits periodic fluctuations. Two linear regression models were constructed by the correlation analyzing between the spectral characteristics of the pressure pulsation signals and the operating conditions. The model for the rotational speed and shaft frequency amplitude of the 4381 propeller indicates that the amplitude of the second harmonic of the shaft frequency increases with the advance coefficient. The model for the skew angle and the fourth harmonic amplitude shows that an increase in the skew angle leads to a gradual increase in the amplitude of the fourth harmonic.
{"title":"Modeling study of wake cavitation characteristics of DTMB propeller based on numerical computation","authors":"Wu Chengkun, Zhifeng Zhu, Cai Bohua, Yao Yong","doi":"10.1177/14750902241272778","DOIUrl":"https://doi.org/10.1177/14750902241272778","url":null,"abstract":"Based on the RANS method using unstructured grids, numerical simulations of cavitation on the DTMB propeller under uniform inflow conditions were conducted. Through numerical studies of pressure pulsations under different cavitation numbers, it was found that at low cavitation numbers, the pressure fluctuations become irregular with higher amplitude and increased noise. As the cavitation number increases, the pressure tends to stabilize and exhibits periodic fluctuations. Two linear regression models were constructed by the correlation analyzing between the spectral characteristics of the pressure pulsation signals and the operating conditions. The model for the rotational speed and shaft frequency amplitude of the 4381 propeller indicates that the amplitude of the second harmonic of the shaft frequency increases with the advance coefficient. The model for the skew angle and the fourth harmonic amplitude shows that an increase in the skew angle leads to a gradual increase in the amplitude of the fourth harmonic.","PeriodicalId":20667,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment","volume":"31 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-14DOI: 10.1177/14750902241272867
Huan Xie, Wei Zeng, Dong-run Zhu, Wen Sun, Hong Song
The subsea pipeline connector (SPC) located at suspended span section not only bears the internal pressure from the oil and nature gas of the pipeline, but also needs to withstand the periodic drag force generated by vortex-induced vibration (VIV). This situation may cause fatigue failure of the flange connector fastening bolts. Reasonable preload value can reduce the fatigue stress and improve the fatigue life of the SPC bolts. This paper establishes a calculation model of the SPC drag force under VIV located at suspended span section. Normal distribution function is used to establish random models of preload for corner control pretension method and hydraulic tension pretension method considering the scatter of the preload value. On this basis, the stochastic finite element model (S-FEM) of SPC bolts is established to analyze bolts force under random preload considering VIV. The regression equation of strain-life for smooth fatigue specimens of bolt materials is applied to obtain preload-fatigue life curves of SPC bolts under different pretension methods. Then it is used to analyze the preload scatter on fatigue life of SPC bolts located at suspended span section. The analysis results indicate that the fatigue life dispersion of SPC bolts pre tightened by hydraulic tension pretension method is smaller compared with the corner control pretension method. Compared with the preload value determined by ASME code, increasing the SPC bolts preload appropriately can improve the fatigue life of SPC fastening bolts located at suspended span section.
{"title":"Effect of preload scatter on fatigue life of subsea pipeline connector bolts located at suspended span section","authors":"Huan Xie, Wei Zeng, Dong-run Zhu, Wen Sun, Hong Song","doi":"10.1177/14750902241272867","DOIUrl":"https://doi.org/10.1177/14750902241272867","url":null,"abstract":"The subsea pipeline connector (SPC) located at suspended span section not only bears the internal pressure from the oil and nature gas of the pipeline, but also needs to withstand the periodic drag force generated by vortex-induced vibration (VIV). This situation may cause fatigue failure of the flange connector fastening bolts. Reasonable preload value can reduce the fatigue stress and improve the fatigue life of the SPC bolts. This paper establishes a calculation model of the SPC drag force under VIV located at suspended span section. Normal distribution function is used to establish random models of preload for corner control pretension method and hydraulic tension pretension method considering the scatter of the preload value. On this basis, the stochastic finite element model (S-FEM) of SPC bolts is established to analyze bolts force under random preload considering VIV. The regression equation of strain-life for smooth fatigue specimens of bolt materials is applied to obtain preload-fatigue life curves of SPC bolts under different pretension methods. Then it is used to analyze the preload scatter on fatigue life of SPC bolts located at suspended span section. The analysis results indicate that the fatigue life dispersion of SPC bolts pre tightened by hydraulic tension pretension method is smaller compared with the corner control pretension method. Compared with the preload value determined by ASME code, increasing the SPC bolts preload appropriately can improve the fatigue life of SPC fastening bolts located at suspended span section.","PeriodicalId":20667,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment","volume":"77 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-31DOI: 10.1177/14750902241271800
Xinran Ji, Chuanle Xu, Zhiyuan Ren, Daoru Wang
Rip currents pose a common natural hazard at coastal tourist beaches, presenting a significant threat to the safety of beachgoers and beach management. To better understand the characteristics of rip currents, particularly those induced by irregular waves on a barred beach, this study utilized a Boussinesq-type, phase-resolving hydrodynamic model for numerical simulations. We investigated various factors, including significant wave height, peak period, incident angle, and bottom friction, to assess their impact on rip currents formation. The results of our research reveal some key insights. Firstly, an increase in significant wave height and peak period fosters the development of rip currents. However, beyond a certain threshold, the intensity of the rip currents decreases. Conversely, a larger incident angle tends to reduce the intensity of rip currents. Additionally, higher bottom friction leads to increased energy dissipation during wave propagation, consequently resulting in decreased rip currents intensity. In an effort to create a more precise representation of real sea conditions, multi-directional waves were employed as incident waves in this study. An analysis of different standard deviations of directional distributions revealed that as the directional spread of incident waves widens, the waves become more susceptible to breaking, ultimately leading to a reduction in the intensity of rip currents.
{"title":"Numerical investigation of rip currents near a barred beach induced by irregular waves","authors":"Xinran Ji, Chuanle Xu, Zhiyuan Ren, Daoru Wang","doi":"10.1177/14750902241271800","DOIUrl":"https://doi.org/10.1177/14750902241271800","url":null,"abstract":"Rip currents pose a common natural hazard at coastal tourist beaches, presenting a significant threat to the safety of beachgoers and beach management. To better understand the characteristics of rip currents, particularly those induced by irregular waves on a barred beach, this study utilized a Boussinesq-type, phase-resolving hydrodynamic model for numerical simulations. We investigated various factors, including significant wave height, peak period, incident angle, and bottom friction, to assess their impact on rip currents formation. The results of our research reveal some key insights. Firstly, an increase in significant wave height and peak period fosters the development of rip currents. However, beyond a certain threshold, the intensity of the rip currents decreases. Conversely, a larger incident angle tends to reduce the intensity of rip currents. Additionally, higher bottom friction leads to increased energy dissipation during wave propagation, consequently resulting in decreased rip currents intensity. In an effort to create a more precise representation of real sea conditions, multi-directional waves were employed as incident waves in this study. An analysis of different standard deviations of directional distributions revealed that as the directional spread of incident waves widens, the waves become more susceptible to breaking, ultimately leading to a reduction in the intensity of rip currents.","PeriodicalId":20667,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment","volume":"24 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-24DOI: 10.1177/14750902241270814
Meiqi Ji, Xuerong Cui, Juan Li, Bin Jiang, Lei Li, Shibao Li, Jianhang Liu
Underwater target localization technology plays a vital role in the development and utilization of marine resources. Due to the multipath effect in the hydroacoustic channel, the received signal is the superposition of a series of direct and reflected acoustic paths, making it challenging to accurately identify the direct path using existing methods. To address this issue, this paper proposes a high-precision direct path recognition method based on Light Gradient Boosting Machine (LightGBM), which utilizes the amplitude, Time of Arrival (TOA), reception angle, and phase of the received pulse as input features. Meanwhile, the direct linear conversion of acoustic wave propagation time from transmitter to receiver into a distance value, as commonly observed in radio ranging in air, is not feasible. Consequently, a method based on Effective Sound Velocity (ESV) is introduced to compensate for the bending of sound rays. By utilizing the recognized direct path delay value and the sound velocity value after compensating for sound ray bending, we can calculate the precise position of underwater targets. Experimental results validate the effectiveness of the proposed method in significantly improving the accuracy of underwater target localization.
{"title":"A high-precision localization method for underwater targets incorporating direct path recognition and sound rays bending compensation","authors":"Meiqi Ji, Xuerong Cui, Juan Li, Bin Jiang, Lei Li, Shibao Li, Jianhang Liu","doi":"10.1177/14750902241270814","DOIUrl":"https://doi.org/10.1177/14750902241270814","url":null,"abstract":"Underwater target localization technology plays a vital role in the development and utilization of marine resources. Due to the multipath effect in the hydroacoustic channel, the received signal is the superposition of a series of direct and reflected acoustic paths, making it challenging to accurately identify the direct path using existing methods. To address this issue, this paper proposes a high-precision direct path recognition method based on Light Gradient Boosting Machine (LightGBM), which utilizes the amplitude, Time of Arrival (TOA), reception angle, and phase of the received pulse as input features. Meanwhile, the direct linear conversion of acoustic wave propagation time from transmitter to receiver into a distance value, as commonly observed in radio ranging in air, is not feasible. Consequently, a method based on Effective Sound Velocity (ESV) is introduced to compensate for the bending of sound rays. By utilizing the recognized direct path delay value and the sound velocity value after compensating for sound ray bending, we can calculate the precise position of underwater targets. Experimental results validate the effectiveness of the proposed method in significantly improving the accuracy of underwater target localization.","PeriodicalId":20667,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment","volume":"425 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-24DOI: 10.1177/14750902241270842
Qiusu Wang, Mingyu Fu, Yujie Xu, Yuchao Wang
In this paper, a state-constrained safety adaptive trajectory tracking control scheme for a hovercraft with enhanced prescribed performance is studied. Firstly, considering the position error, a novel pair of prescribed monotone tube boundary functions combined with a sliding mode is introduced to obtain virtual velocity control laws, and the position error is simplified into an equivalent unconstrained control system by adopting the transformed error function. Unlike traditional prescribed performance control, the new function has a quantitative relationship between (transient and steady-state) control performance and some practical user-defined metrics such as overshoot, precision, and convergence time, and is less conservative. Therefore, this method is convenient for design and engineering practice. Secondly, in order to solve problems of velocity safety constraints, a novel asymmetric integral barrier Lyapunov function (AIBLF) has been adopted to limit velocities of hovercraft within the asymmetric safety constraints. Moreover, a bioinspired neurodynamic model is introduced to handle differential explosion of virtual control laws. For the sake of estimating the unknown terms such as the control system uncertainties, the neural networks (NNs) are utilized. Total control system is ultimately uniformly bounded according to Lyapunov stability theories. Effectiveness and superiority of the proposed control scheme are verified by comparative simulation.
{"title":"A state-constrained safety adaptive trajectory tracking control scheme for a hovercraft with enhanced prescribed performance","authors":"Qiusu Wang, Mingyu Fu, Yujie Xu, Yuchao Wang","doi":"10.1177/14750902241270842","DOIUrl":"https://doi.org/10.1177/14750902241270842","url":null,"abstract":"In this paper, a state-constrained safety adaptive trajectory tracking control scheme for a hovercraft with enhanced prescribed performance is studied. Firstly, considering the position error, a novel pair of prescribed monotone tube boundary functions combined with a sliding mode is introduced to obtain virtual velocity control laws, and the position error is simplified into an equivalent unconstrained control system by adopting the transformed error function. Unlike traditional prescribed performance control, the new function has a quantitative relationship between (transient and steady-state) control performance and some practical user-defined metrics such as overshoot, precision, and convergence time, and is less conservative. Therefore, this method is convenient for design and engineering practice. Secondly, in order to solve problems of velocity safety constraints, a novel asymmetric integral barrier Lyapunov function (AIBLF) has been adopted to limit velocities of hovercraft within the asymmetric safety constraints. Moreover, a bioinspired neurodynamic model is introduced to handle differential explosion of virtual control laws. For the sake of estimating the unknown terms such as the control system uncertainties, the neural networks (NNs) are utilized. Total control system is ultimately uniformly bounded according to Lyapunov stability theories. Effectiveness and superiority of the proposed control scheme are verified by comparative simulation.","PeriodicalId":20667,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment","volume":"27 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-17DOI: 10.1177/14750902241265903
Kaihang Zhang, Wei Zhang, Honghan Zhang, Yiming Yang, Yefan Shi
This paper investigates a trajectory tracking control method for multi-underactuated underwater vehicle (AUV) formations with uncertain model parameters and external environmental disturbances. Firstly, a dual closed-loop fixed-time integral sliding mode controller is designed. By combining fixed-time theory and integral sliding mode control, this controller ensures the stability of the formation tracking and guarantees the convergence of the tracking error to zero within a fixed time duration. Secondly, an adaptive radial basis function (RBF) neural network controller is integrated with a conditional integrator to address uncertainties in model parameters, approximation errors, and external environmental disturbances in practical multi-AUV systems. This controller exhibits robustness and adaptivity. Additionally, a virtual leader strategy is employed to enhance the robustness of the formation system and prevent formation collapse caused by leader AUV failures. Finally, simulation results validate the effectiveness of the proposed formation controller, demonstrating accurate trajectory tracking by the AUV formation.
{"title":"Fixed-time integral sliding mode formation trajectory tracking control for multi-underactuated autonomous underwater vehicle in three-dimensional space","authors":"Kaihang Zhang, Wei Zhang, Honghan Zhang, Yiming Yang, Yefan Shi","doi":"10.1177/14750902241265903","DOIUrl":"https://doi.org/10.1177/14750902241265903","url":null,"abstract":"This paper investigates a trajectory tracking control method for multi-underactuated underwater vehicle (AUV) formations with uncertain model parameters and external environmental disturbances. Firstly, a dual closed-loop fixed-time integral sliding mode controller is designed. By combining fixed-time theory and integral sliding mode control, this controller ensures the stability of the formation tracking and guarantees the convergence of the tracking error to zero within a fixed time duration. Secondly, an adaptive radial basis function (RBF) neural network controller is integrated with a conditional integrator to address uncertainties in model parameters, approximation errors, and external environmental disturbances in practical multi-AUV systems. This controller exhibits robustness and adaptivity. Additionally, a virtual leader strategy is employed to enhance the robustness of the formation system and prevent formation collapse caused by leader AUV failures. Finally, simulation results validate the effectiveness of the proposed formation controller, demonstrating accurate trajectory tracking by the AUV formation.","PeriodicalId":20667,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment","volume":"12 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142219076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}