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Multiobjective trajectory optimization of intelligent electro-hydraulic shovel

《机械工程前沿(英文)》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0706-2

摘要: Multiobjective trajectory planning is still face challenges due to certain practical requirements and multiple contradicting objectives optimized simultaneously. In this paper, a multiobjective trajectory optimization approach that sets energy consumption, execution time, and excavation volume as the objective functions is presented for the electro-hydraulic shovel (EHS). The proposed cubic polynomial S-curve is employed to plan the crowd and hoist speed of EHS. Then, a novel hybrid constrained multiobjective evolutionary algorithm based on decomposition is proposed to deal with this constrained multiobjective optimization problem. The normalization of objectives is introduced to minimize the unfavorable effect of orders of magnitude. A novel hybrid constraint handling approach based on -constraint and the adaptive penalty function method is utilized to discover infeasible solution information and improve population diversity. Finally, the entropy weight technique for order preference by similarity to an ideal solution method is used to select the most satisfied solution from the Pareto optimal set. The performance of the proposed strategy is validated and analyzed by a series of simulation and experimental studies. Results show that the proposed approach can provide the high-quality Pareto optimal solutions and outperforms other trajectory optimization schemes investigated in this article.

关键词: trajectory planning     electro-hydraulic shovel     cubic polynomial S-curve     multiobjective optimization     entropy weight technique    

Vehicle roll stability control with active roll-resistant electro-hydraulic suspension

Lijun XIAO, Ming WANG, Bangji ZHANG, Zhihua ZHONG

《机械工程前沿(英文)》 2020年 第15卷 第1期   页码 43-54 doi: 10.1007/s11465-019-0547-9

摘要: This study examines roll stability control for vehicles with an active roll-resistant electro-hydraulic suspension (RREHS) subsystem under steering maneuvers. First, we derive a vehicle model with four degrees of freedom and incorporates yaw and roll motions. Second, an optimal linear quadratic regulator controller is obtained in consideration of dynamic vehicle performance. Third, an RREHS subsystem with an electric servo-valve actuator is proposed, and the corresponding dynamic equations are obtained. Fourth, field experiments are conducted to validate the performance of the vehicle model under sine-wave and double-lane-change steering maneuvers. Finally, the effectiveness of the active RREHS is determined by examining vehicle responses under sine-wave and double-lane-change maneuvers. The enhancement in vehicle roll stability through the RREHS subsystem is also verified.

关键词: electro-hydraulic suspension     roll stability     LQR     experiment    

基于扩展干扰观测器的电液执行器的模糊阻抗控制 Regular Papers-Research Articles

Ming-jie LI, Jian-hua WEI, Jin-hui FANG, Wen-zhuo SHI, Kai GUO

《信息与电子工程前沿(英文)》 2019年 第20卷 第9期   页码 1221-1233 doi: 10.1631/FITEE.1800155

摘要: 在本文中,我们同时处理遭受外干扰及参数不确定影响的单出杆电液执行器的速度控制和力控制。在某些应用中,速度控制和力控制两者都有要求。阻抗控制和扩展干扰观测器的结合可以解决该问题。阻抗控制可调节执行器的速度和输出力之间的动态关系,有助于执行器与作用环境或者工件间避免冲击和保持合适的接触力。阻抗规则参数可由模糊算法调节。扩展干扰观测器被用于补偿外部干扰和参数不确定性,实现精确的速度跟踪。为扩展干扰器的开发,提出精确的负载力动力学模型。分析了系统稳定性。实验数据表明所提控制算法具有高精度速度跟踪性能,同时具有良好的力调节能力,在工程机械和装配中具有较大应用前景。

关键词: 模糊控制;阻抗控制;干扰观测器;参数不确定性;电液执行器    

大口径望远镜主镜支撑位置控制系统的定量反馈控制器设计与测试 Article

Xiong-bin PENG, Guo-fang GONG, Hua-yong YANG, Hai-yang LOU, Wei-qiang WU, Tong LIU

《信息与电子工程前沿(英文)》 2017年 第18卷 第10期   页码 1624-1634 doi: 10.1631/FITEE.1601104

摘要: 确保主镜支撑位置控制系统的响应速度、定位精度及稳定性是提高大口径望远镜成像质量的关键。镜室的姿态调整及环境温度的变化会改变位置控制系统的工作参数,加剧系统非线性,增加望远镜精确成像的难度。我们提出了基于定量反馈理论的位置控制器设计,辨识系统工作参数,确定工作参数范围,设计补偿控制器及前置滤波器。仿真及实验结果说明,主镜支撑位置控制系统的定量反馈控制器在保证较好的响应速度前提下,具有很好的位置控制精度及稳定性。

关键词: 大口径望远镜;定量反馈理论;主镜位置控制系统;微米级位置控制能力;系统辨识;鲁棒稳定性    

双轮铣槽机铣削系统自适应模糊积分滑模转速控制

Qi-yan Tian, Jian-hua Wei, Jin-hui Fang, Kai Guo,jhfang@zju.edu.cn

《信息与电子工程前沿(英文)》 2016年 第17卷 第1期   页码 55-66 doi: 10.1631/FITEE.15a0160

摘要: 目的:随着地下连续墙施工工法和双轮铣槽机技术不断发展,实现对双轮铣槽机铣削系统铣轮工作转速的快速精确控制具有重要意义。在负载特性未知、扰动复杂的情况下,本文基于自适应模糊积分滑模(AFISMC)控制算法,实现对铣削系统铣轮转速的良好控制。 创新点:在双轮铣槽机铣轮铣削过程中,铣轮转速控制受到岩石和土壤未知负载特性的影响,同时地质条件不断变化。由于岩石和土壤复杂的负载特性,铣轮的切削扭矩与地质条件、铣轮进给速度等均存在耦合关系,而且其动态特性复杂未知,无法建立准确的数学模型。本文针对以上难点,设计新型自适应模糊积分滑模转速控制器。 方法:针对双轮铣槽机铣削系统的特性,提出一种基于自适应模糊积分滑模控制(AFISMC)的铣轮转速控制方案。该控制方案将自适应控制的参数自整定特性、积分滑模控制的鲁棒性以及模糊系统独立于数学模型的特性结合起来。通过自适应模糊系统对被控对象未知模型有效逼近,使用反步法对控制器进行设计,采用Lyapunov理论证明整个闭环系统(包括自适应模糊推理系统、积分滑模控制器和被控对象)的稳定性。 结论:在双轮铣槽机液压模拟实验台对不同工况下的铣轮转速控制进行实验,分别采用PI、ISMC和AFISMC三种控制方法进行对比。实验结果表明AFISMC控制算法在跟踪和抗干扰方面均表现出良好的控制性能。

关键词: 铣削系统;电液系统;铣削转速控制;自适应模糊积分滑模控制    

Toward autonomous mining: design and development of an unmanned electric shovel via point cloud-based

《机械工程前沿(英文)》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0686-2

摘要: With the proposal of intelligent mines, unmanned mining has become a research hotspot in recent years. In the field of autonomous excavation, environmental perception and excavation trajectory planning are two key issues because they have considerable influences on operation performance. In this study, an unmanned electric shovel (UES) is developed, and key robotization processes consisting of environment modeling and optimal excavation trajectory planning are presented. Initially, the point cloud of the material surface is collected and reconstructed by polynomial response surface (PRS) method. Then, by establishing the dynamical model of the UES, a point to point (PTP) excavation trajectory planning method is developed to improve both the mining efficiency and fill factor and to reduce the energy consumption. Based on optimal trajectory command, the UES performs autonomous excavation. The experimental results show that the proposed surface reconstruction method can accurately represent the material surface. On the basis of reconstructed surface, the PTP trajectory planning method rapidly obtains a reasonable mining trajectory with high fill factor and mining efficiency. Compared with the common excavation trajectory planning approaches, the proposed method tends to be more capable in terms of mining time and energy consumption, ensuring high-performance excavation of the UES in practical mining environment.

关键词: autonomous excavation     unmanned electric shovel     point cloud     excavation trajectory planning    

Identification of resistant pharmaceuticals in ozonation using QSAR modeling and their fate in electro-peroxone

《环境科学与工程前沿(英文)》 2021年 第15卷 第5期 doi: 10.1007/s11783-021-1394-6

摘要:

• Effect of converting ozonation to E-peroxone was studied on pharmaceutical removal.

关键词: Ozone     Electro-peroxone     Wastewater     Quantitative structure activity relationship     Advanced oxidation processes    

Effect of Joule heating on electro-osmotic flow in a closed-end micro-channel with isothermal and convective

Liang ZHAO, Linhua LIU,

《能源前沿(英文)》 2009年 第3卷 第4期   页码 381-388 doi: 10.1007/s11708-009-0057-2

摘要: The effect of Joule heating on the steady state electro-osmotic flow in a closed-end micro-channel is studied through numerical simulation with the finite volume method. The velocity field and the temperature field are described by a rigorous mathematical model. Thermophysical properties including viscosity and thermal conductivity are considered to be temperature-dependent. The simulations show that the presence of Joule heating causes an increase in temperature and a decrease in viscosity in the whole micro-channel, which, thereafter, induce a large velocity near the wall and an increase in fluid velocity at the central region in order to maintain a zero flow rate at the cross section of the micro-channel. The effect of Joule heating on the induced pressure gradient is also studied, which is very important for the application of the closed-end micro-channel as a micro-actuator. The results reveal that the induced pressure gradient, taking into consideration Joule heating, is significantly smaller than that without considering Joule heating when the wall temperature of the micro-channel is constant. The induced pressure gradient difference between considering Joule heating and without considering Joule heating is small under the convective boundary condition.

关键词: closed-end micro-channel     electrical double layer     electro-osmotic flow     induced pressure gradient     Joule heating    

Effect of polymer structures on electro-optical properties of polymer stabilized liquid crystal films

WANG Shoulian, HE Jie, ZENG Yu, YAN Bin, WANG Yinghan

《化学科学与工程前沿(英文)》 2008年 第2卷 第3期   页码 265-268 doi: 10.1007/s11705-008-0054-8

摘要: The polymer stabilized liquid crystal (PSLC) film is a relatively novel electro-optical material, which is generally obtained by dissolving a small amount of a bifunctional photoreactive monomer in a low molecular mass liquid crystal. In this paper, the PSLC films were prepared with photoreactive biphenyl methacrylate monomers by photopolymerization induced phase separation. The effects of liquid crystal concentration, curing time, monomer structures and alignment layer on the electro-optical properties of PSLC films were investigated. The results show that the transmittance in the OFF state () increased with the liquid crystal concentration, but the driving voltage decreased. was also influenced by the curing time. Furthermore, when polyimide was used as alignment layer, the films prepared from the bifunctional monomer shows a higher T, while those from the single functional monomer exhibited a deformed electro-optical curve due to the unsteady polymer networks.

Platinum on nitrogen doped graphene and tungsten carbide supports for ammonia electro-oxidation reaction

《化学科学与工程前沿(英文)》 2022年 第16卷 第6期   页码 930-938 doi: 10.1007/s11705-021-2130-2

摘要: Ammonia electrooxidation reaction involving multistep electron-proton transfer is a significant reaction for fuel cells, hydrogen production and understanding nitrogen cycle. Platinum has been established as the best electrocatalyst for ammonia oxidation in aqueous alkaline media. In this study, Pt/nitrogen-doped graphene (NDG) and Pt/tungsten monocarbide (WC)/NDG are synthesized by a wet chemistry method and their ammonia oxidation activities are compared to commercial Pt/C. Pt/NDG exhibits a specific activity of 0.472 mA∙cm–2, which is 44% higher than commercial Pt/C, thus establishing NDG as a more effective support than carbon black. Moreover, it is demonstrated that WC as a support also impacts the activity with further 30% increase in comparison to NDG. Surface modification with Ir resulted in the best electrocatalytic activity with Pt-Ir/WC/NDG having almost thrice the current density of commercial Pt/C. This work adds insights regarding the role of NDG and WC as efficient supports along with significant impact of Ir surface modification.

关键词: Ammonia electro-oxidation reaction     electrocatalyst supports     platinum     nitrogen doped graphene     tungsten carbide    

Combination of the direct electro-Fenton process and bioremediation for the treatment of pyrene-contaminated

Wendi XU,Shuhai GUO,Gang LI,Fengmei LI,Bo WU,Xinhong GAN

《环境科学与工程前沿(英文)》 2015年 第9卷 第6期   页码 1096-1107 doi: 10.1007/s11783-015-0804-z

摘要: A combined treatment technology (DEF-BIO) using the direct electro-Fenton (DEF) process and bioremediation (BIO) was established in this study. The performance of the DEF-BIO process on the remediation of a pyrene (PYR)-contaminated soil was evaluated in a slurry reactor. The appropriate order of application was to conduct the DEF process followed by BIO, evaluated through analysis of the degradation characteristics of each process individually. In addition, the application time of the DEF process affected the efficiency of the combined process. The optimum time to apply the DEF process was determined through an analysis of the induced changes in PYR intermediates, pH, soil organic matter (SOM) and bacteria. The optimum application time of the DEF process was 6 h. All the induced changes were beneficial for the BIO phase. The removal of PYR was 91.02% for DEF–BIO after 72 h, and the efficiency was almost 50% increased, compared with the individual DEF and BIO treatments. Therefore, the combined process of DEF–BIO process may be an efficient and promising method for the remediation.

关键词: direct electro-Fenton     bioremediation     slurry reactor     combined process     pyrene    

Micro-spectrophotometer based on micro electro-mechanical systems technology

ZHOU Lianqun, LI Zhenggang, WU Yihui, ZHANG Ping, XUAN Ming, JIA Hongguang

《机械工程前沿(英文)》 2008年 第3卷 第1期   页码 37-43 doi: 10.1007/s11465-008-0001-x

摘要: A new mini-spectrophotometer is developed by adopting micro-silicon-slit and micro-silicon-fixer, which are based on micro electro-mechanical systems (MEMS) technology. Both the micro-silicon-slit and the micro-silicon-fixer have their own features, such as small volume and high precision, which are laid out and analyzed later. Meantime, through the analysis of the sample cell’s optical characteristics that have some impacts on the linearity of the spectrophotometer, a relationship equation, which is about the impact of the refractive index of the sample cell and the tested medium on the variety of the transmitted light intensity and the absorbency, is put forward. When the water and the air are taken as the referenced medium, the experiments demonstrate that the difference of the refractive index of the references does not influence the correlation coefficient and the slope of the absorbency-concentration curve. The final results show that the new mini-spectrophotometer with micro-silicon-slit and micro-silicon-fixer is worked out, its correlation coefficient > 0.999, and its refractive index resolving power is better than 0.01.

关键词: mini-spectrophotometer     referenced     micro-silicon-fixer     electro-mechanical     correlation coefficient    

Electroconductive RGO-MXene membranes with wettability-regulated channels: improved water permeability and electro-enhanced

《环境科学与工程前沿(英文)》 2023年 第17卷 第1期 doi: 10.1007/s11783-023-1601-8

摘要:

● Electroconductive RGO-MXene membranes were fabricated.

关键词: Reduced graphene oxide     MXene     Membrane     Water permeance     Dye rejection     Electro-assistance    

Efficient and selective electro-reduction of nitrobenzene by the nano-structured Cu catalyst prepared

Yali CHEN,Lu XIONG,Weikang WANG,Xing ZHANG,Hanqing YU

《环境科学与工程前沿(英文)》 2015年 第9卷 第5期   页码 897-904 doi: 10.1007/s11783-015-0782-1

摘要: Pollution caused by toxic nitrobenzene has been a widespread environmental concern. Selective reduction of nitrobenzene to aniline is beneficial to further efficient and cost-effective biologic treatment. Electrochemical reduction is a promising method and Cu-based catalysts have been found to be an efficient cathode material for this purpose. In this work, Cu catalysts with different morphologies were fabricated on Ti plate using a facile electrodepositon method via tuning the applied voltage. The dendritic nano-structured Cu catalysts obtained at high applied voltages exhibited an excellent efficiency and selectivity toward the reduction of nitrobenzene to aniline. Effects of the working potential and initial nitrobenzene concentration on the selective reduction of nitrobenzene to aniline using the Cu/Ti electrode were investigated. A high rate constant of 0.0251 min and 97.1% aniline selectivity were achieved. The fabricated nano-structured Cu catalysts also exhibited good stability. This work provides a facile way to prepare highly efficient, cost-effective, and stable nano-structured electrocatalysts for pollutant reduction.

关键词: nitrobenzene     nano-structured Cu     electro-reduction     voltage-dependent electrodeposition     high selectivity     high stability    

Effects of slip length and hydraulic diameter on hydraulic entrance length of microchannels with superhydrophobic

Wenchi GONG, Jun SHEN, Wei DAI, Zeng DENG, Xueqiang DONG, Maoqiong GONG

《能源前沿(英文)》 2020年 第14卷 第1期   页码 127-138 doi: 10.1007/s11708-020-0661-8

摘要: This paper investigated effects of slip length and hydraulic diameter on the hydraulic entrance length of laminar flow in superhydrophobic microchannels. Numerical investigations were performed for square microchannels with Re ranging between 0.1 and 1000. It is found that superhydrophobic microchannels have a longer hydraulic entrance length than that of conventional ones by nearly 26.62% at a low Re. The dimensionless hydraulic entrance length slightly increases with the increasing slip length at approximately Re<10, and does not vary with the hydraulic diameter. A new correlation to predict the entrance length in square microchannels with different slip lengths was developed, which has a satisfying predictive performance with a mean absolute relative deviation of 5.69%. The results not only ascertain the flow characteristics of superhydrophobic microchannels, but also suggest that super hydrophobic microchannels have more significant advantages for heat transfer enhancement at a low Re.

关键词: laminar flow     hydraulic entrance length     super hydrophobic surface     slip length     hydraulic diameter    

标题 作者 时间 类型 操作

Multiobjective trajectory optimization of intelligent electro-hydraulic shovel

期刊论文

Vehicle roll stability control with active roll-resistant electro-hydraulic suspension

Lijun XIAO, Ming WANG, Bangji ZHANG, Zhihua ZHONG

期刊论文

基于扩展干扰观测器的电液执行器的模糊阻抗控制

Ming-jie LI, Jian-hua WEI, Jin-hui FANG, Wen-zhuo SHI, Kai GUO

期刊论文

大口径望远镜主镜支撑位置控制系统的定量反馈控制器设计与测试

Xiong-bin PENG, Guo-fang GONG, Hua-yong YANG, Hai-yang LOU, Wei-qiang WU, Tong LIU

期刊论文

双轮铣槽机铣削系统自适应模糊积分滑模转速控制

Qi-yan Tian, Jian-hua Wei, Jin-hui Fang, Kai Guo,jhfang@zju.edu.cn

期刊论文

Toward autonomous mining: design and development of an unmanned electric shovel via point cloud-based

期刊论文

Identification of resistant pharmaceuticals in ozonation using QSAR modeling and their fate in electro-peroxone

期刊论文

Effect of Joule heating on electro-osmotic flow in a closed-end micro-channel with isothermal and convective

Liang ZHAO, Linhua LIU,

期刊论文

Effect of polymer structures on electro-optical properties of polymer stabilized liquid crystal films

WANG Shoulian, HE Jie, ZENG Yu, YAN Bin, WANG Yinghan

期刊论文

Platinum on nitrogen doped graphene and tungsten carbide supports for ammonia electro-oxidation reaction

期刊论文

Combination of the direct electro-Fenton process and bioremediation for the treatment of pyrene-contaminated

Wendi XU,Shuhai GUO,Gang LI,Fengmei LI,Bo WU,Xinhong GAN

期刊论文

Micro-spectrophotometer based on micro electro-mechanical systems technology

ZHOU Lianqun, LI Zhenggang, WU Yihui, ZHANG Ping, XUAN Ming, JIA Hongguang

期刊论文

Electroconductive RGO-MXene membranes with wettability-regulated channels: improved water permeability and electro-enhanced

期刊论文

Efficient and selective electro-reduction of nitrobenzene by the nano-structured Cu catalyst prepared

Yali CHEN,Lu XIONG,Weikang WANG,Xing ZHANG,Hanqing YU

期刊论文

Effects of slip length and hydraulic diameter on hydraulic entrance length of microchannels with superhydrophobic

Wenchi GONG, Jun SHEN, Wei DAI, Zeng DENG, Xueqiang DONG, Maoqiong GONG

期刊论文