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近海复杂环境下UUV动态路径规划方法研究

智能系统学报 2024年第1期19卷 114-121页

作者：张宏瀚王亚博李娟王元慧严浙平哈尔滨工程大学智能科学与工程学院黑龙江哈尔滨150001

为解决近海环境下水下无人航行器(unmanned underwater vehicle,UUV)的动态路径规划问题,本文提出一种结合全局和局部动态路径规划的算法。首先,本文提出一种基于自适应目标引导的快速拓展随机树算法,以增加随机树生长的方向性,并通过... 详细信息

为解决近海环境下水下无人航行器(unmanned underwater vehicle,UUV)的动态路径规划问题,本文提出一种结合全局和局部动态路径规划的算法。首先,本文提出一种基于自适应目标引导的快速拓展随机树算法,以增加随机树生长的方向性,并通过转向和重选策略减少无效拓展加快算法的收敛速度。接着,获得全局路径之后使用自适应子节点选取策略获取动态窗口法的子目标点,将复杂的全局动态任务规划分解为多个简单的动态路劲规划,从而防止动态窗口法陷入局部极小值。最后,通过UUV出港任务仿真实验验证了算法的有效性和实用性。

关键词：水下无人航行器动态路径规划快速拓展随机树动态窗口自适应水下环境局部路径规划避障

Influence of Initial Water Content on Synthesis of Silicalite-1 Zeolite

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China Petroleum Processing & Petrochemical Technology 2017年第4期19卷 11-19页

作者： zhang honghan zhang Shanhe Wang Haoren Li Chunyi State Key Laboratory of Heavy Oil Processing China University of Petroleum Qingdao 266580

The effect of initial water content on the synthesis of silicalite-1 zeolite and its reaction performance in methanol to propylene(MTP) reaction was comprehensively investigated. The as-synthesized samples were characterized by XRD,N_2 adsorption and desorption, SEM, and FTIR techniques, and studied for the methanol to propylene(MTP) reaction. The results showed that the initial water content played a crucial role on the particle size and porous structure of the silicalite-1 zeolites. It was found that adding initial water to reach a certain amount, the crystal size reduced obviously and the mesoporous structure appeared. Upon applying the silicalite-1 zeolite samples in the MTP reaction, they showed excellent catalytic performance to reach a highest propene mass yield of 26.81%(on the CH_2 basis) and a P/E ratio of 6.28 in 2 h. The excellent catalytic performance of silicalite-1 can be attributed to its mesoporous structure.

关键词： initial water content hierarchical pore silicalite-1 MTP

A Synchronization Acquisition Algorithm Based on the Frequency Hopping Pulses Combining

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China Communications 2024年第4期21卷 74-87页

作者： She honghan Cheng Yufan zhang Wenzihan zhang Yaohui Zhao Yuheng Shen Haoran Mou Ying National Key Laboratory of Wireless Communications UESTCChengdu 611731China

As modern electromagnetic environments are more and more complex,the anti-interference performance of the synchronization acquisition is becoming vital in wireless *** the rapid development of the digital signal processing technologies,some synchronization acquisition algorithms for hybrid direct-sequence(DS)/frequency hopping(FH)spread spectrum communications have been ***,these algorithms do not focus on the analysis and the design of the synchronization acquisition under typical *** this paper,a synchronization acquisition algorithm based on the frequency hopping pulses combining(FHPC)is ***,the proposed algorithm is composed of two modules:an adaptive interference suppression(IS)module and an adaptive combining decision *** adaptive IS module mitigates the effect of the interfered samples in the time-domain or the frequencydomain,and the adaptive combining decision module can utilize each frequency hopping pulse to construct an anti-interference decision metric and generate an adaptive acquisition decision threshold to complete the *** and simulation demonstrate that the proposed algorithm significantly enhances the antiinterference and anti-noise performances of the synchronization acquisition for hybrid DS/FH communications.

关键词： adaptive anti-interference frequency hopping synchronization acquisition

Global path planning methods of UUV in coastal environment

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软件 2014年第5期35卷 4-12页

作者： zhang honghan LIU Xiaofu YAN Zheping ZHOU Jiajia College of Automation Harbin Engineering University

In coastal environment,the motion of unmanned underwater vehicle(UUV)is influenced significantly by complex *** operational performance of UUV can be greatly improved when the impact of ocean current is considered.A global path planning method of the static obstacle environmental space is addressed in the ***,according to the typically coastal vortex,a model of ocean current is proposed and the influence to the motion of UUV is ***,to satisfy the rapid requirement in path planning,a heuristic A*algorithm is used to design global planning path with multiple ***,to meet the UUV’s smooth path requirement,Bezier curve theory is *** experiments are performed to illustrate the feasibility of the algorithm in the steady current and vortex environment.

关键词： Coastal environment Vortex Unmanned underwater vehicle(UUV) Path planning

Yuzaoea gen. nov., a new biraphid diatom(Bacillariophyceae)genus and its phylogenetic significance

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Acta Oceanologica Sinica 2024年第2期43卷 130-136页

作者： honghan Liu Chenhong Li Lang Li Xuesong Li Lin Sun Junrong Liang Jun zhang Yahui Gao Changping Chen Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems and School of Life Sciences Xiamen UniversityXiamen 361102China State Key Laboratory of Marine Environmental Science Xiamen UniversityXiamen 361102China Guangxi Key Laboratory of Marine Environmental Science Guangxi Academy of Marine SciencesGuangxi Academy of SciencesNanning 530007China Beibu Gulf Marine Industry Research Institute Fangchenggang 538000China

The flexed frustules in pennate diatoms are usually associated with monoraphid diatoms. Interestingly, we found a biraphid diatom species with flexed frustules in an offshore intertidal beach environment on Weizhou Island,Beihai City, Guangxi Zhuang Autonomous Region, China. Therefore, based on morphological characteristics, we described a new genus of diatoms Yuzaoea sinensis gen. et sp. nov. CH Li, HH Liu, YH Gao & CP Chen. The frustule of this genus is characterized by heterogeneous frustule with one concave valve and one convex valve,complete raphe on both valves, straight and moderately eccentric raphe, uniseriate striae and girdle bands with a single row of areolae. The most identifying feature of this genus was the flexed frustule, which is rare in biraphid diatoms and common in monoraphid diatoms. We compared the morphometric characteristics of genus Yuzaoea with genus Rhoikoneis and several genera within the family Rhoicospheniaceae, including Rhoicosphenia,Campylopyxis, and Cuneolus. Phylogenetic analyses based on SSU rRNA and rbc L showed that the genus Yuzaoea was the sister group to the clade of Rhoicosphenia with a high support value(bootstrap values = 100%), and the clade “Yuzaoea+Rhoicosphenia” was sister to the clade of monoraphid diatoms, in which the genera Achnanthidium, Planothidium and some Cocconeis with high support values(bootstrap = 100%).Morphologically, the genus Yuzaoea shares many morphological features with monoraphid diatoms like genera Achnanthidium and Planothidium and the members within the Rhoicospheniaceae. Therefore, based on a combined morphological studies and phylogenetic results we suggested that this branch may represented the evolution of one kind monoraphid diatoms, from biraphid diatoms(e.g. genus Yuzaoea), to incompleted biraphid diatoms(e.g. genera Rhoicosphenia, Campylopyxis), to monoraphid diatoms(e.g. genera Achnanthidium and Planothidium).

关键词： biraphid diatom marine new genus Rhoicospheniaceae taxonomy Yuzaoea

Robust H∞ Control of Unmanned Underwater Vehicle in Vertical Plane Based on T-S Model and Parallel Distributed Compensation

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Robust H∞ Control of Unmanned Underwater Vehicle in Vertica...

On the Trajectory Tracking Problem of Underactuated Deep Diving AUV

第37届中国控制会议

作者： zhang Xun Liao Hongzhou Zhou Jiajia zhang honghan College of Automation Harbin Engineering University

Excellent depth control capability of UUV（Unmanned Underwater Vehicle） is a key factor for completing specific tasks. Considering the variance of UUV’s speed and ocean current interference, depth and pitch control model of UUV are established based on T-S model. The H∞ controller in vertical plane movement is designed applying the method of parallel distributed compensation（PDC）. Aiming to meet the design requirements with the large pitch angle when UUV is submerging,the depth-pitch coordinated control method with variant depth is used to control the submergence of UUV. Simulation result shows that the control method can effectively control depth and pitch of UUV in given speed interval and has good dynamic performance. Moreover, the method can effectively decrease the pitch angel when UUV is submerging and has strong inhibitory ability on ocean current disturbance.

关键词： UUV H∞ control T-S model PDC Depth-pitch coordinated control method

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On the Trajectory Tracking Problem of Underactuated Deep Div...

第37届中国控制会议

作者： honghan zhang Yajie Xu Jiajia Zhou Hao Fan College of Automation Harbin Engineering University

The large dive depth of underactuated AUV leads to the complicated external interference in the dive process, which greatly affects the performance of AUV dive motion control. In order to solve the problem of external interference, this paper first divides the external interferences into the constant current interferences and the buoyancy interferences that vary with the depth changes. Then the mathematical model is built and the adaptive rate is designed for the external interference. Secondly, the AUV dynamic model under external interference is established and the three-dimensional trajectory tracking is implemented by the backstepping control method which defines the virtual velocity error variables. The control method can ensure that the AUV can dive to a designated area when there is external interference and can also solve the singular value problem in the traditional backstepping method. Finally, the system stability is proved by Lyapunov function. The simulation results show the effectiveness of the proposed method, which achieve the purpose of controlling the deep-depth spiral dive of the AUV.

关键词： Backstepping external interference deep-sea AUV three-dimensional trajectory tracking

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基于领航跟随法的多AUV编队控制算法研究

仪器仪表学报 2019年第6期40卷 237-246页

作者：李娟袁锐锟张宏瀚哈尔滨工程大学水下机器人技术重点实验室哈尔滨150001 哈尔滨工程大学自动化学院哈尔滨150001

针对已知路径下基于领航者的多自主水下机器人(AUV)编队队形控制问题,提出了一种AUV路径控制和编队协调控制相结合的新型编队控制器。其中,AUV的路径跟踪控制采用反步滑模控制器,将AUV位置、姿态和时变速度跟踪转化虚拟速度控制,使AUV... 详细信息

针对已知路径下基于领航者的多自主水下机器人(AUV)编队队形控制问题,提出了一种AUV路径控制和编队协调控制相结合的新型编队控制器。其中,AUV的路径跟踪控制采用反步滑模控制器,将AUV位置、姿态和时变速度跟踪转化虚拟速度控制,使AUV能达到期望的位置、速度等,避免了反步控制中的奇异值问题,并能够很好实现不确定的模型的控制,同时又提高了跟随者协同定位精度;在路径跟踪控制基础上,编队协调控制器将领航者与跟随者的位置误差控制转化为跟随者的速度误差控制,使跟随者能快速达到期望位置,从而使所有AUV实现期望的队形并保持。仿真实验对该控制策略进行了可行性验证,结果表明,该算法提高了编队的响应速度、控制精度和稳定性;再应用3台AUV进行了湖上试验验证,证明了该控制策略的有效性,能有效应用到实际中。

关键词：自主水下机器人路径跟踪控制编队协调控制滑模控制

Research on Backstepping Tracking Control of Deep-diving AUV Based on Biological Inspiration

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Research on Backstepping Tracking Control of Deep-diving AUV...