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A grouping module assessment method for ocean engineering systems: Subsea tree system as a case 海洋工程系统的分组模块评估方法:以海底树系统为例
IF 1.8 4区 工程技术 Q3 ENGINEERING, MARINE Pub Date : 2024-09-19 DOI: 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.
在海洋工程环境中,由于实验成本高昂,很难获得复杂系统的高质量故障数据。此外,使用单一模型分析风险、可靠性、可用性和可维护性也是一大挑战。本文基于故障树模型、动态贝叶斯模型和马尔可夫模型,提出了一种具有多种维护模式的海洋工程系统状态评估方法。该方法充分发挥了三种方法的优势,全面分析了风险、可靠性、可用性和可维护性。该方法利用故障树和马尔可夫模型对故障数据进行预处理,然后将预处理后的故障数据输入基于动态贝叶斯理论的多状态退化模型。考虑到无修复、完美修复、不完美修复和预防性修复等维护策略,对模型进行迭代和调整,直到模型处理完所有事件数据,且更新后的模型能最好地反映系统状态。以海底生产系统的海底树为例,对该方法进行了验证。得到的树可靠性指数(平均无故障时间)与海上和陆上可靠性数据库的故障统计基本一致,验证了所提方法的准确性。
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引用次数: 0
Integrated design method for protection against vibration of offshore platform plate structure 海上平台板结构振动防护综合设计方法
IF 1.8 4区 工程技术 Q3 ENGINEERING, MARINE Pub Date : 2024-09-19 DOI: 10.1177/14750902241271865
Ziwei Deng, Xuchen Jia, Zijian Li, Xu Sun, Fuzhen Pang, Baocheng Zhang
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.
本文综合了模态规避方法、基座设计方法和动态减震器理论,研究了海上平台板结构的振动控制技术。我们通过控制振动激振载荷、振动传递和振动耗能,开发了一种综合的振动抑制设计方法。首先,采用模态规避设计来抑制振动沿板结构传播路径的传递。随后,对基座结构进行基座优化,以减弱输入端的振动激励。最后,采用动态吸振器理论进一步控制主要振动频率响应,实现多目标振动控制。案例模拟结果表明,综合设计方法降低了 113.75、145.61 和 153 Hz 的加速度振动水平,该方法可指导海上平台板结构的多目标振动控制。
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引用次数: 0
Effect of pre-swirl stator angles on broadband noise considering hydrodynamic performance of pump-jet propeller 考虑到泵式喷气推进器的流体力学性能,预旋流定子角度对宽带噪声的影响
IF 1.8 4区 工程技术 Q3 ENGINEERING, MARINE Pub Date : 2024-09-15 DOI: 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.
泵喷气推进器由转子、定子和管道组成。预旋流定子用于优化进入转子的流量。泵喷气推进器的流体动力学性能和噪声性能随定子角度的变化而变化。在本研究中,通过基于雷诺平均纳维-斯托克斯方程的计算流体动力学模拟,评估了全尺寸潜艇和泵喷气推进器的流体动力学性能。此外,还利用莱特希尔方程、格林函数和壁面压力谱预测了宽带噪声、叶片通过频率噪声和一个重要因素,即水下辐射噪声。从流场中提取非稳态力来获得叶片通过频率噪声。由于没有小涡流,无法直接从流场中计算宽带噪声,因此使用壁压谱来获得高频宽带噪声。对包括宽带噪声和叶片通过频率噪声在内的整体噪声进行了评估。考虑到泵喷气推进器的推进效率和噪声水平,确定了自推进点转子的最佳定子角度。
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引用次数: 0
A benchmark study on the energy efficiency and environmental impacts of alternative fuels in gulet-type sailing yachts 关于小帆船使用替代燃料的能效和环境影响的基准研究
IF 1.8 4区 工程技术 Q3 ENGINEERING, MARINE Pub Date : 2024-09-14 DOI: 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%.
桅杆型游艇以其独特的船体形式和双桅帆船或凯奇型索具成为航海文化的象征之一。在实现海运业脱碳目标的同时,此类游艇的能效和排放控制也提上了日程。在这一动机的驱动下,我们针对小帆船型游艇开展了一项新的基准研究,以评估采用液化天然气或甲醇作为 MDO 主要燃料替代品所带来的能效和环境影响。基准研究分两步进行:首先介绍现有小帆船的设计和推进特性,然后详细分析使用替代燃料的能效和环境影响。因此,对船体形式为圆形和横截面船尾的 57 艘小帆船进行了分析、建模,并介绍了其总体特征。建模后,使用 Holtrop-Mennen 方法和 CFD 预测了船体形式的阻力和有效功率。第一步是获得船体周围的流动特性,并利用之前的实验研究对结果进行验证。然后,比较发动机的安装容量和计算容量,并计算年排放率和能效指数(EEI),以进行环境影响评估。最后,考虑到能效和设计,讨论了使用液化天然气或甲醇为燃料的推进系统对小帆船的适用性。结果表明,改用替代燃料可使小帆船的能效指数提高 20% 以上。
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引用次数: 0
Modeling study of wake cavitation characteristics of DTMB propeller based on numerical computation 基于数值计算的 DTMB 螺旋桨尾流气蚀特性建模研究
IF 1.8 4区 工程技术 Q3 ENGINEERING, MARINE Pub Date : 2024-09-14 DOI: 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.
基于使用非结构网格的 RANS 方法,对均匀流入条件下 DTMB 螺旋桨上的气蚀进行了数值模拟。通过对不同空化数下压力脉动的数值研究发现,在低空化数下,压力波动变得不规则,振幅增大,噪声增加。随着空化数的增加,压力趋于稳定并呈现周期性波动。通过分析压力脉动信号的频谱特征与运行条件之间的相关性,建立了两个线性回归模型。4381 型螺旋桨的转速和轴频振幅模型表明,轴频二次谐波振幅随推进系数的增加而增大。倾斜角和四次谐波振幅模型表明,倾斜角增大会导致四次谐波振幅逐渐增大。
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引用次数: 0
Effect of preload scatter on fatigue life of subsea pipeline connector bolts located at suspended span section 预紧力分散对位于悬吊跨度段的海底管道连接螺栓疲劳寿命的影响
IF 1.8 4区 工程技术 Q3 ENGINEERING, MARINE Pub Date : 2024-09-14 DOI: 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.
位于悬吊跨度段的海底管道连接器(SPC)不仅要承受来自管道石油和天然气的内部压力,还需要承受涡流诱导振动(VIV)产生的周期性阻力。这种情况可能会导致法兰连接紧固螺栓的疲劳失效。合理的预紧力值可以降低疲劳应力,提高 SPC 螺栓的疲劳寿命。本文建立了位于悬挂跨度截面 VIV 下 SPC 阻力的计算模型。考虑到预紧力值的分散性,采用正态分布函数建立了转角控制预紧力法和液压拉伸预紧力法的预紧力随机模型。在此基础上,建立了 SPC 螺栓的随机有限元模型 (S-FEM),以分析考虑 VIV 的随机预紧力下的螺栓力。应用螺栓材料光滑疲劳试样的应变-寿命回归方程,得到不同预紧方法下 SPC 螺栓的预紧-疲劳寿命曲线。然后利用该方程分析了预紧力散布对位于悬挂跨度截面上的 SPC 螺栓疲劳寿命的影响。分析结果表明,与转角控制预紧法相比,液压张力预紧法预紧的 SPC 螺栓的疲劳寿命散度较小。与 ASME 规范确定的预紧力值相比,适当增加 SPC 螺栓的预紧力可以提高悬挂跨段 SPC 紧固螺栓的疲劳寿命。
{"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}
引用次数: 0
Numerical investigation of rip currents near a barred beach induced by irregular waves 对不规则波浪诱发的栅栏海滩附近撕裂流的数值研究
IF 1.8 4区 工程技术 Q3 ENGINEERING, MARINE Pub Date : 2024-08-31 DOI: 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.
激流是沿海旅游海滩常见的自然灾害,对海滩游客的安全和海滩管理构成重大威胁。为了更好地了解激流的特征,特别是由不规则波浪在有栅栏的海滩上引起的激流,本研究采用了布西内斯克(Boussinesq)型相位分解流体动力学模型进行数值模拟。我们研究了各种因素,包括显著波高、峰值周期、入射角和底部摩擦力,以评估它们对撕裂流形成的影响。我们的研究结果揭示了一些重要的观点。首先,显波高度和峰值周期的增加会促进裂流的发展。然而,超过一定临界值后,撕裂流的强度就会降低。相反,入射角越大,裂流强度越小。此外,较高的底部摩擦力会增加波浪传播过程中的能量消耗,从而导致撕裂流强度降低。为了更精确地反映真实海况,本研究采用了多向波作为入射波。对不同方向分布标准偏差的分析表明,随着入射波方向分布的扩大,波浪变得更容易破碎,最终导致裂流强度降低。
{"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}
引用次数: 0
A high-precision localization method for underwater targets incorporating direct path recognition and sound rays bending compensation 结合直接路径识别和声射线弯曲补偿的水下目标高精度定位方法
IF 1.8 4区 工程技术 Q3 ENGINEERING, MARINE Pub Date : 2024-08-24 DOI: 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.
水下目标定位技术在海洋资源的开发和利用中发挥着至关重要的作用。由于水声信道中的多径效应,接收到的信号是一系列直达声路和反射声路的叠加,因此利用现有方法准确识别直达声路具有一定难度。针对这一问题,本文提出了一种基于光梯度提升机(LightGBM)的高精度直接路径识别方法,该方法利用接收脉冲的振幅、到达时间(TOA)、接收角和相位作为输入特征。同时,将声波从发射器到接收器的传播时间直接线性转换为距离值的方法并不可行,这在空气中无线电测距中很常见。因此,我们引入了一种基于有效声速(ESV)的方法来补偿声射线的弯曲。通过利用已识别的直接路径延迟值和补偿声射线弯曲后的声速值,我们可以计算出水下目标的精确位置。实验结果验证了所提方法在显著提高水下目标定位精度方面的有效性。
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引用次数: 0
A state-constrained safety adaptive trajectory tracking control scheme for a hovercraft with enhanced prescribed performance 增强规定性能的气垫船状态约束安全自适应轨迹跟踪控制方案
IF 1.8 4区 工程技术 Q3 ENGINEERING, MARINE Pub Date : 2024-08-24 DOI: 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.
本文研究了一种具有增强规定性能的气垫船状态约束安全自适应轨迹跟踪控制方案。首先,考虑位置误差,引入一对新的规定单调管边界函数与滑动模式相结合,得到虚拟速度控制律,并通过采用变换误差函数将位置误差简化为等效无约束控制系统。与传统的规定性能控制不同,新函数的(瞬态和稳态)控制性能与用户定义的一些实际指标(如过冲、精度和收敛时间)之间存在定量关系,且不太保守。因此,这种方法便于设计和工程实践。其次,为了解决速度安全约束问题,采用了一种新颖的非对称积分屏障李亚普诺夫函数(AIBLF),在非对称安全约束条件下限制气垫船的速度。此外,还引入了生物启发神经动力学模型来处理虚拟控制法则的差分爆炸。为了估算控制系统不确定性等未知项,利用了神经网络(NN)。根据 Lyapunov 稳定性理论,总控制系统最终是均匀有界的。通过比较仿真验证了所提控制方案的有效性和优越性。
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引用次数: 0
Fixed-time integral sliding mode formation trajectory tracking control for multi-underactuated autonomous underwater vehicle in three-dimensional space 三维空间多欠动自主潜水器的定时积分滑动模式编队轨迹跟踪控制
IF 1.8 4区 工程技术 Q3 ENGINEERING, MARINE Pub Date : 2024-08-17 DOI: 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.
本文研究了一种针对具有不确定模型参数和外部环境干扰的多欠动水下航行器(AUV)编队的轨迹跟踪控制方法。首先,设计了一种双闭环定时积分滑模控制器。通过将固定时间理论和积分滑模控制相结合,该控制器确保了编队跟踪的稳定性,并保证跟踪误差在固定时间内收敛为零。其次,将自适应径向基函数(RBF)神经网络控制器与条件积分器相结合,以解决实际多无人潜航器系统中的模型参数不确定性、近似误差和外部环境干扰问题。该控制器具有鲁棒性和适应性。此外,还采用了虚拟领航员策略,以增强编队系统的鲁棒性,防止领航员 AUV 故障导致编队崩溃。最后,仿真结果验证了所提编队控制器的有效性,证明了 AUV 编队的精确轨迹跟踪。
{"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}
引用次数: 0
期刊
Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
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