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Motion planning and tracking control of a four-wheel independently driven steered mobile robot with multiplemaneuvering modes

Xiaolong ZHANG, Yu HUANG, Shuting WANG, Gen LI, Yuanlong XIE, Wei MENG

《机械工程前沿(英文)》 2021年 第16卷 第3期   页码 504-527 doi: 10.1007/s11465-020-0626-y

摘要: Safe and effective autonomous navigation in dynamic environments is challenging for four-wheel independently driven steered mobile robots (FWIDSMRs) due to the flexible allocation of multiple maneuver modes. To address this problem, this study proposes a novel multiple mode-based navigation system, which can achieve efficient motion planning and accurate tracking control. To reduce the calculation burden and obtain a comprehensive optimized global path, a kinodynamic interior–exterior cell exploration planning method, which leverages the hybrid space of available modes with an incorporated exploration guiding algorithm, is designed. By utilizing the sampled subgoals and the constructed global path, local planning is then performed to avoid unexpected obstacles and potential collisions. With the desired profile curvature and preselected mode, a fuzzy adaptive receding horizon control is proposed such that the online updating of the predictive horizon is realized to enhance the trajectory-following precision. The tracking controller design is achieved using the quadratic programming (QP) technique, and the primal–dual neural network optimization technique is used to solve the QP problem. Experimental results on a real-time FWIDSMR validate that the proposed method shows superior features over some existing methods in terms of efficiency and accuracy.

关键词: mobile robot     multiple maneuvering mode     motion planning     tracking control     receding horizon control    

Virtual reality system of manned maneuvering unit taking into consideration the disturbance from an astronaut

CHENG Jian, FAN Xiu-min, XU An, HONG Xin, HUANG Wei-dong

《机械工程前沿(英文)》 2006年 第1卷 第3期   页码 282-287 doi: 10.1007/s11465-006-0042-y

摘要: This paper describes a manned maneuvering unit (MMU) virtual reality system. Based on the dynamics/kinematics model of an astronaut equipped with an MMU, a disturbance model of the astronaut s arms under zero gravity conditions is developed. After measuring three initial-position information, the astronaut s arms tracking information is inputted by some tracker setting on an operator using real-time emendation and correction. Finally, the paper presents two different results between loading and unloading the disturbance model within the progress of simulation. From the different results, we find that the motion of an astronaut s arms has greater influence over space walking with the same control mode. The MMU virtual reality provides a new method for the simulation of real space walking, and also a perfect method for developing prototype MMU.

关键词: real-time emendation     disturbance     maneuvering     MMU     correction    

Amodified variable rate particle filter for maneuvering target tracking

Yun-fei GUO,Kong-shuai FAN,Dong-liang PENG,Ji-an LUO,Han SHENTU

《信息与电子工程前沿(英文)》 2015年 第16卷 第11期   页码 985-994 doi: 10.1631/FITEE.1500149

摘要: To address the problem of maneuvering target tracking, where the target trajectory has prolonged smooth regions and abrupt maneuvering regions, a modified variable rate particle filter (MVRPF) is proposed. First, a Cartesian-coordinate based variable rate model is presented. Compared with conventional variable rate models, the proposed model does not need any prior knowledge of target mass or external forces. Consequently, it is more convenient in practical tracking applications. Second, a maneuvering detection strategy is adopted to adaptively adjust the parameters in MVRPF, which helps allocate more state points at high maneuver regions and fewer at smooth regions. Third, in the presence of small measurement errors, the unscented particle filter, which is embedded in MVRPF, can move more particles into regions of high likelihood and hence can improve the tracking performance. Simulation results illustrate the effectiveness of the proposed method.

关键词: Maneuvering target tracking     Prolonged smooth regions     Variable rate model     Maneuver detection    

非理想条件下空分复用研究与应用 None

Ji-ying XIANG

《信息与电子工程前沿(英文)》 2018年 第19卷 第3期   页码 357-366 doi: 10.1631/FITEE.1700827

摘要: 对空分复用技术中的非理想因素进行了理论分析,并探讨了在上述非理想工程条件下空分复用的应用,给出了实测数据。对于信道条件非理想的场景,即多通道之间相关性高,条件数大,导致高层间干扰,需要通过最优化用户匹配和降维达到最优容量。对于信道测量非理想的场景,深入分析了反馈式和非反馈式的优劣,并指出即使信道不满足互易性条件,非反馈式也是优选方法。针对上述问题,进行了理论分析和外场实测。

关键词: 第五代移动通讯;条件数;信道互易性;信道反馈测量模式;信道非反馈式测量模式    

IP组播路由协议的研究与实现

李炜

《中国工程科学》 2002年 第4卷 第1期   页码 82-88

摘要:

概述了组播路由协议。分析了协议独立的组播路由一稀疏模式(PIM-SM)的缺陷,提出多个会聚 点(RPs)的PIM-SM的改进机制。多个RPs机制有效地提高了原有单个RP的PIM-SM协议的健壮性,有利 于实现负载均衡、分类业务及提高系统的容错性能,并讨论多个RPs机制的开销问题。分析了 PIM-SM实现细 节和组播技术的前景。

关键词: 协议独立的组播路由一稀疏模式(PIM-SM)     多会聚点(RPs)     组播    

An assessment of surrogate fuel using Bayesian multiple kernel learning model in sight of sooting tendency

《能源前沿(英文)》 2022年 第16卷 第2期   页码 277-291 doi: 10.1007/s11708-021-0731-6

摘要: An integrated and systematic database of sooting tendency with more than 190 kinds of fuels was obtained through a series of experimental investigations. The laser-induced incandescence (LII) method was used to acquire the 2D distribution of soot volume fraction, and an apparatus-independent yield sooting index (YSI) was experimentally obtained. Based on the database, a novel predicting model of YSI values for surrogate fuels was proposed with the application of a machine learning method, named the Bayesian multiple kernel learning (BMKL) model. A high correlation coefficient (0.986) between measured YSIs and predicted values with the BMKL model was obtained, indicating that the BMKL model had a reliable and accurate predictive capacity for YSI values of surrogate fuels. The BMKL model provides an accurate and low-cost approach to assess surrogate performances of diesel, jet fuel, and biodiesel in terms of sooting tendency. Particularly, this model is one of the first attempts to predict the sooting tendencies of surrogate fuels that concurrently contain hydrocarbon and oxygenated components and shows a satisfying matching level. During surrogate formulation, the BMKL model can be used to shrink the surrogate candidate list in terms of sooting tendency and ensure the optimal surrogate has a satisfying matching level of soot behaviors. Due to the high accuracy and resolution of YSI prediction, the BMKL model is also capable of providing distinguishing information of sooting tendency for surrogate design.

关键词: sooting tendency     yield sooting index     Bayesian multiple kernel learning     surrogate assessment     surrogate formulation    

Robust SVM-direct torque control of induction motor based on sliding mode controller and sliding mode

Abdelkarim AMMAR,Amor BOUREK,Abdelhamid BENAKCHA

《能源前沿(英文)》 2020年 第14卷 第4期   页码 836-849 doi: 10.1007/s11708-017-0444-z

摘要: This paper proposes a design of control and estimation strategy for induction motor based on the variable structure approach. It describes a coupling of sliding mode direct torque control (DTC) with sliding mode flux and speed observer. This algorithm uses direct torque control basics and the sliding mode approach. A robust electromagnetic torque and flux controllers are designed to overcome the conventional SVM-DTC drawbacks and to ensure fast response and full reference tracking with desired dynamic behavior and low ripple level. The sliding mode controller is used to generate reference voltages in stationary frame and give them to the controlled motor after modulation by a space vector modulation (SVM) inverter. The second aim of this paper is to design a sliding mode speed/flux observer which can improve the control performances by using a sensorless algorithm to get an accurate estimation, and consequently, increase the reliability of the system and decrease the cost of using sensors. The effectiveness of the whole composed control algorithm is investigated in different robustness tests with simulation using Matlab/Simulink and verified by real time experimental implementation based on dS pace 1104 board.

关键词: induction motor     direct torque control (DTC)     space vector modulation (SVM)     sliding mode control (SMC)     sliding mode observer (SMO)     dS1104    

Analysis of the treatment outcomes of esophageal variceal bleeding patients from multiple centers in

WANG Zhiqiang

《医学前沿(英文)》 2008年 第2卷 第2期   页码 171-173 doi: 10.1007/s11684-008-0031-0

摘要: This study aimed to investigate the treatment outcomes of esophageal variceal bleeding (EVB) in China. A total of 1087 cases were collected from 19 hospitals in 16 large and medium sized cities across China between January 1st, 2005 and January 1st, 2006. There were 313 cases (29.0%) of mild (<400 mL), 494 cases (45.8%) of moderate (400–1500 mL) and 272 cases (25.2%) of severe (>1500 mL) bleeding. Successful hemostasis was achieved in 89.8% of cases. Seven hundred and eighty-five cases were treated by medication with a hemostasis rate of 91.8%. Seventy-one cases were treated using a Sengstaken-Blakemore tube with a hemostasis rate of 54.9%. Thirty-seven cases were treated with emergency endoscopic variceal ligation with a hemostasis rate of 83.8%. Seventy-seven cases were treated with endoscopic sclerotherapy with a hemostasis rate of 94.8%. Forty-three cases were treated with emergency surgical operation with a hemostasis rate of 95.3%. Sixty-six cases were treated with combined therapy with a hemostasis rate of 97.0%. There was a significant difference ( < 0.01) in the successful hemostasis rate between different treatments. The overall mortality was 10.1%, among which 6.6% was directly caused by bleeding. The multivariate logistic regression analysis shows that the severity of bleeding, treatment methods, liver dysfunction and activation of hepatitis were predictive factors for successful hemostasis. Most cases of EVB were mild and moderate in severity. The first-line treatment for EVB is medication. Emergency endoscopic intervention has not been widely available yet. The overall management outcome of EVB has been improved.

关键词: significant difference     predictive     medication     first-line treatment     bleeding    

基于位置旋转变换和非均匀快速傅立叶变换的机动目标高效相参检测 Research Articles

靳科1,赖涛2,齐艳丽3,黄洁1,赵拥军1

《信息与电子工程前沿(英文)》 2020年 第21卷 第8期   页码 1251-1266 doi: 10.1631/FITEE.1900272

摘要: 长时间相参积累能够显著提升雷达对机动目标的检测和运动参数估计性能。然而,相参积累期间目标的线性距离徙动、二次距离徙动和多普勒频率徙动将导致检测性能急剧下降。提出基于位置旋转变换和非均匀快速傅里叶变换的高效稳健相参积累方法。首先,利用二阶Keystone变换消除二次距离徙动。然后,利用旋转角度和多普勒频率之间的对应关系,构建相位补偿函数,从而利用位置旋转和非均匀快速傅里叶变换实现高效的参数估计。与现有代表性算法相比,所提算法能以较低运算复杂度实现近乎理想的检测性能。最后,基于雷达实测数据的实验证明所提算法有效。

关键词: 相参积累;机动目标;参数估计;位置旋转变换;非均匀快速傅立叶变换    

基于双重分组和密钥计数的并行认证模式

黄玉划,胡爱群,宋宇波

《中国工程科学》 2004年 第6卷 第7期   页码 70-74

摘要:

由于CBC-MAC模式不可并行处理,提出了一种基于双重分组的并行认证模式(PKCB)。PKCB模式同并行认证模式PMAC相比,安全性和速率都有显著提高,PKCB认证模式与CTR(计数器)加密模式结合可构成分组密码算法的一种全工作模式。在此基础上提出了一种基于密钥计数的并行认证模式(KCTR-MAC)。KCTR-MAC模式安全性比PMAC模式高得多,而速率未降低,KCTR-MAC认证模式和CTR加密模式结合也可构成分组密码算法的一种全工作模式(2CTR),2CTR模式的综合性能不亚于标准模式CCM(CTR with CBC-MAC),是一种安全快速的实用模式。

关键词: 认证模式     CBC-MAC模式     PMAC模式     CTR模式     CCM模式    

多天线非正交多址接入技术:综述 Regular Papers

Fei-yan TIAN, Xiao-ming CHEN

《信息与电子工程前沿(英文)》 2019年 第20卷 第12期   页码 1665-1697 doi: 10.1631/FITEE.1900405

摘要: 作为一种前沿的物理层技术,非正交多址接入技术允许多用户共享同一时空资源,因此增加了可接入用户数量,从而改善频谱效率。在第5代及未来无线通信网络中,非正交多址接入技术为实现大规模万物互联提供了可行方案。然而,严重的共道干扰和较高的实施复杂度阻碍了其在实际系统中的应用。为解决这些问题,多天线技术凭借其在空间自由度上的优势,已被广泛应用于非正交多址接入系统。本文针对多天线技术在非正交多址接入系统中各种各样的应用提供了一个全面综述,主要强调其在消除空间干扰和降低实施复杂度上的优势。特别地,详细调查了多天线技术在两用户、多用户、大规模连接和异构非正交多址接入系统中的应用。最后,预测了未来相关研究方向与挑战。

关键词: 非正交多址接入;多天线技术;B5G;物联网    

Sequential degradation-based burn-in test with multiple periodic inspections

《工程管理前沿(英文)》 2021年 第8卷 第4期   页码 519-530 doi: 10.1007/s42524-021-0166-0

摘要: Burn-in has been proven effective in identifying and removing defective products before they are delivered to customers. Most existing burn-in models adopt a one-shot scheme, which may not be sufficient enough for identification. Borrowing the idea from sequential inspections for remaining useful life prediction and accelerated lifetime test, this study proposes a sequential degradation-based burn-in model with multiple periodic inspections. At each inspection epoch, the posterior probability that a product belongs to a normal one is updated with the inspected degradation level. Based on the degradation level and the updated posterior probability, a product can be disposed, put into field use, or kept in the test till the next inspection epoch. We cast the problem into a partially observed Markov decision process to minimize the expected total burn-in cost of a product, and derive some interesting structures of the optimal policy. Then, algorithms are provided to find the joint optimal inspection period and number of inspections in steps. A numerical study is also provided to illustrate the effectiveness of our proposed model.

关键词: burn-in     degradation     multiple inspections     Wiener process     partially observed Markov decision process    

Sensitivity analysis of the deterioration of concrete strength in marine environment to multiple corrosive

《结构与土木工程前沿(英文)》 2023年 第17卷 第2期   页码 175-190 doi: 10.1007/s11709-021-0791-z

摘要: The corrosion degradation behavior of concrete materials plays a crucial role in the change of its mechanical properties under multi-ion interaction in the marine environment. In this study, the variation in the macro-physical and mechanical properties of concrete with corrosion time is investigated, and the source of micro-corrosion products under different salt solutions in seawater are analyzed. Regardless of the continuous hydration effect of concrete, the damage effects of various corrosive ions (Cl, SO42, and Mg2+, etc.) on the tensile and compressive strength of concrete are discussed based on measurement in different salt solutions. The sensitivity analysis method for concrete strength is used to quantitatively analyze the sensitivity of concrete strength to the effects of each ion in a multi-salt solution without considering the influence of continued hydration. The quantitative results indicate that the addition of Cl can weaken the corrosion effect of SO42 by about 20%, while the addition of Mg2+ or Mg2+ and Cl can strengthen it by 10%–20% during a 600-d corrosion process.

关键词: sensitivity analysis     concrete strength     corrosion deterioration     multi-ion interaction     marine environment    

Probabilistic stability of uncertain composite plates and stochastic irregularity in their buckling mode

《结构与土木工程前沿(英文)》   页码 179-190 doi: 10.1007/s11709-022-0888-z

摘要: In this study, the mechanical properties of the composite plate were considered Gaussian random fields and their effects on the buckling load and corresponding mode shapes were studied by developing a semi-analytical non-intrusive approach. The random fields were decomposed by the Karhunen−Loève method. The strains were defined based on the assumptions of the first-order and higher-order shear-deformation theories. Stochastic equations of motion were extracted using Euler–Lagrange equations. The probabilistic response space was obtained by employing the non-intrusive polynomial chaos method. Finally, the effect of spatially varying stochastic properties on the critical load of the plate and the irregularity of buckling mode shapes and their sequences were studied for the first time. Our findings showed that different shear deformation plate theories could significantly influence the reliability of thicker plates under compressive loading. It is suggested that a linear relationship exists between the mechanical properties’ variation coefficient and critical loads’ variation coefficient. Also, in modeling the plate properties as random fields, a significant stochastic irregularity is obtained in buckling mode shapes, which is crucial in practical applications.

关键词: uncertain composite plate     stochastic assume mode method     Karhunen−Loève theorem     polynomial chaos approach     plate buckling     irregularity in buckling mode shapes    

Group-based multiple pipe routing method for aero-engine focusing on parallel layout

《机械工程前沿(英文)》 2021年 第16卷 第4期   页码 798-813 doi: 10.1007/s11465-021-0645-3

摘要: External pipe routing for aero-engine in limited three-dimensional space is a typical nondeterministic polynomial hard problem, where the parallel layout of pipes plays an important role in improving the utilization of layout space, facilitating pipe assembly, and maintenance. This paper presents an automatic multiple pipe routing method for aero-engine that focuses on parallel layout. The compressed visibility graph construction algorithm is proposed first to determine rapidly the rough path and interference relationship of the pipes to be routed. Based on these rough paths, the information of pipe grouping and sequencing are obtained according to the difference degree and interference degree, respectively. Subsequently, a coevolutionary improved differential evolution algorithm, which adopts the coevolutionary strategy, is used to solve multiple pipe layout optimization problem. By using this algorithm, pipes in the same group share the layout space information with one another, and the optimal layout solution of pipes in this group can be obtained in the same evolutionary progress. Furthermore, to eliminate the minor angle deviation of parallel pipes that would cause assembly stress in actual assembly, an accurate parallelization processing method based on the simulated annealing algorithm is proposed. Finally, the simulation results on an aero-engine demonstrate the feasibility and effectiveness of the proposed method.

关键词: multiple pipe routing     optimization algorithm     aero-engine     pipe grouping     parallel layout    

标题 作者 时间 类型 操作

Motion planning and tracking control of a four-wheel independently driven steered mobile robot with multiplemaneuvering modes

Xiaolong ZHANG, Yu HUANG, Shuting WANG, Gen LI, Yuanlong XIE, Wei MENG

期刊论文

Virtual reality system of manned maneuvering unit taking into consideration the disturbance from an astronaut

CHENG Jian, FAN Xiu-min, XU An, HONG Xin, HUANG Wei-dong

期刊论文

Amodified variable rate particle filter for maneuvering target tracking

Yun-fei GUO,Kong-shuai FAN,Dong-liang PENG,Ji-an LUO,Han SHENTU

期刊论文

非理想条件下空分复用研究与应用

Ji-ying XIANG

期刊论文

IP组播路由协议的研究与实现

李炜

期刊论文

An assessment of surrogate fuel using Bayesian multiple kernel learning model in sight of sooting tendency

期刊论文

Robust SVM-direct torque control of induction motor based on sliding mode controller and sliding mode

Abdelkarim AMMAR,Amor BOUREK,Abdelhamid BENAKCHA

期刊论文

Analysis of the treatment outcomes of esophageal variceal bleeding patients from multiple centers in

WANG Zhiqiang

期刊论文

基于位置旋转变换和非均匀快速傅立叶变换的机动目标高效相参检测

靳科1,赖涛2,齐艳丽3,黄洁1,赵拥军1

期刊论文

基于双重分组和密钥计数的并行认证模式

黄玉划,胡爱群,宋宇波

期刊论文

多天线非正交多址接入技术:综述

Fei-yan TIAN, Xiao-ming CHEN

期刊论文

Sequential degradation-based burn-in test with multiple periodic inspections

期刊论文

Sensitivity analysis of the deterioration of concrete strength in marine environment to multiple corrosive

期刊论文

Probabilistic stability of uncertain composite plates and stochastic irregularity in their buckling mode

期刊论文

Group-based multiple pipe routing method for aero-engine focusing on parallel layout

期刊论文