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High-bandwidth nanopositioning via active control of system resonance

Linlin LI, Sumeet S. APHALE, Limin ZHU

《机械工程前沿（英文）》 2021年 第16卷 第2期   页码 331-339 doi: 10.1007/s11465-020-0619-x

摘要： Typically, the achievable positioning bandwidth for piezo-actuated nanopositioners is severely limited by the first, lightly-damped resonance. To overcome this issue, a variety of open- and closed-loop control techniques that commonly combine damping and tracking actions, have been reported in literature. However, in almost all these cases, the achievable closed-loop bandwidth is still limited by the original open-loop resonant frequency of the respective positioning axis. Shifting this resonance to a higher frequency would undoubtedly result in a wider bandwidth. However, such a shift typically entails a major mechanical redesign of the nanopositioner. The integral resonant control (IRC) has been reported earlier to demonstrate the significant performance enhancement, robustness to parameter uncertainty, gua-ranteed stability and design flexibility it affords. To further exploit the IRC scheme’s capabilities, this paper presents a method of actively shifting the resonant frequency of a nanopositioner’s axis, thereby delivering a wider closed-loop positioning bandwidth when controlled with the IRC scheme. The IRC damping control is augmented with a standard integral tracking controller to improve positioning accuracy. And both damping and tracking control parameters are analytically optimized to result in a Butterworth Filter mimicking pole-placement—maximally flat passband response. Experiments are conducted on a nanopositioner’s axis with an open-loop resonance at 508 Hz. It is shown that by employing the active resonance shifting, the closed-loop positioning bandwidth is increased from 73 to 576 Hz. Consequently, the root-mean-square tracking errors for a 100 Hz triangular trajectory are reduced by 93%.

关键词： nanopositioning stage     high-bandwidth     resonant mode control     tracking control     integral resonant control    

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Preload characteristics identification of the piezoelectric-actuated 1-DOF compliant nanopositioning

Ruizhou WANG, Xianmin ZHANG

《机械工程前沿（英文）》 2015年 第10卷 第1期   页码 20-36 doi: 10.1007/s11465-015-0328-z

摘要：

Packaged piezoelectric ceramic actuators (PPCAs) and compliant mechanisms are attractive for nanopositioning and nanomanipulation due to their ultra-high precision. The way to create and keep a proper and steady connection between both ends of the PPCA and the compliant mechanism is an essential step to achieve such a high accuracy. The connection status affects the initial position of the terminal moving plate, the positioning accuracy and the dynamic performance of the nanopositioning platform, especially during a long-time or high-frequency positioning procedure. This paper presents a novel external preload mechanism and tests it in a 1-degree of freedom (1-DOF) compliant nanopositioning platform. The 1-DOF platform utilizes a parallelogram guiding mechanism and a parallelogram load mechanism to provide a more accurate actual input displacement and output displacement. The simulation results verify the proposed stiffness model and dynamic model of the platform. The values of the preload displacement, actual input displacement and output displacement can be measured by three capacitive sensors during the whole positioning procedure. The test results show the preload characteristics vary with different types or control modes of the PPCA. Some fitting formulas are derived to describe the preload displacement, actual input displacement and output displacement using the nominal elongation signal of the PPCA. With the identification of the preload characteristics, the actual and comprehensive output characteristics of the PPCA can be obtained by the strain gauge sensor (SGS) embedded in the PPCA.

关键词： nanopositioning     preload characteristic     packaged piezoelectric ceramic actuator     compliant mechanism    

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Compressor performance of two-stage turbocharging system

HE Yituan, MA Chaochen, WEI Mingshan, ZHU Zhifu, HE Yituan

《机械工程前沿（英文）》 2008年 第3卷 第2期   页码 218-221 doi: 10.1007/s11465-008-0027-0

摘要： To study the performance of high and low stage compressors and that of the system as a whole, a two-stage turbocharging system was matched, and a special two-stage turbocharging system test bench was built. For each test curve, the speeds of the two stage turbochargers were adjusted to the fixed data, and a compressor performance experiment was performed. The results showed many differences between the corrected mass flow and the actual mass flow of the high pressure (HP) stage compressor. To find out the actual supercharging effect of the two-stage turbocharging system, it is better to adopt the actual mass flow. The two-stage turbocharging system in this paper has much higher efficiency under most operating conditions if the pressure ratio assignment is 1:1. The system can get very high supercharging pressure when the speeds of the two stage turbochargers are rather low, which ensures the system’s security and reliability.

关键词： special two-stage     HP     performance experiment     reliability     actual supercharging    

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以电子方式提升洛伦兹力驱动器的大行程纳米定位精度 Research Article

Bimal Jeet GOTEEA,张前军,董为

《信息与电子工程前沿（英文）》 2023年 第24卷 第7期   页码 1080-1092 doi: 10.1631/FITEE.2200255

摘要： 本文展现了一种基于洛伦兹力驱动器和柔顺导向的精密厘米级定位器。通过使用一个额外的数模转换器（DAC）和运算放大器（op amp）电路，以及合适的控制器将定位精度提高到纳米级。首先，基于柔顺导向模型的刚度为驱动器设计了恰当的线圈。然后通过有限元分析（FEA）验证了柔顺机构和驱动器的性能。基于此，提出一种通过电子方式提升定位性能的方法及控制方案。最后，构建了原理样机并对其性能进行评估。该定位器的特色在于其在10 mm行程内实现10 nm分辨率。所提出的方案可以拓展适用于其他同类型系统。

关键词： 纳米定位；柔顺导向；大行程；音圈电机；洛伦兹力驱动器    

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Two-stage stochastic programming with robust constraints for the logistics network post-disruption response

《工程管理前沿（英文）》   页码 67-81 doi: 10.1007/s42524-022-0240-2

摘要： Logistics networks (LNs) are essential for the transportation and distribution of goods or services from suppliers to consumers. However, LNs with complex structures are more vulnerable to disruptions due to natural disasters and accidents. To address the LN post-disruption response strategy optimization problem, this study proposes a novel two-stage stochastic programming model with robust delivery time constraints. The proposed model jointly optimizes the new-line-opening and rerouting decisions in the face of uncertain transport demands and transportation times. To enhance the robustness of the response strategy obtained, the conditional value at risk (CVaR) criterion is utilized to reduce the operational risk, and robust constraints based on the scenario-based uncertainty sets are proposed to guarantee the delivery time requirement. An equivalent tractable mixed-integer linear programming reformulation is further derived by linearizing the CVaR objective function and dualizing the infinite number of robust constraints into finite ones. A case study based on the practical operations of the JD LN is conducted to validate the practical significance of the proposed model. A comparison with the rerouting strategy and two benchmark models demonstrates the superiority of the proposed model in terms of operational cost, delivery time, and loading rate.

关键词： logistics network design     post-disruption response strategy     two-stage stochastic programming     conditional value at risk     robust constraint    

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Efficiency measurement for mixed two-stage nonhomogeneous network processes with shared extra intermediate

Qingxian AN, Xuyang LIU, Shijie DING

《工程管理前沿（英文）》 2020年 第7卷 第2期   页码 259-274 doi: 10.1007/s42524-019-0080-x

摘要： Unreasonable allocation of shared resources reduces the system efficiency and is a considerable operational risk. Sub-processes with insufficient portion of shared resources could not help accomplish complicated tasks, and overstaffing and idle resources will occur in the sub-processes assigned with redundant shared resources. This unfair portion distribution may cause internal contradictions among sub-processes and even lead to the collapsing of the entire system. This study proposes a data-driven, mixed two-stage network data envelopment analysis model. This method aims to reasonably define the allocation portion of shared extra intermediate resources among several nonhomogeneous subsystems and measure the overall system performance. A data set of 58 international hotels is used to test the features of the proposed model.

关键词： shared resource allocation     mixed two-stage system     data envelopment analysis     efficiency    

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Modified landfill gas generation rate model of first-order kinetics and two-stage reaction

Jiajun CHEN , Hao WANG , Na ZHANG ,

《环境科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 313-319 doi: 10.1007/s11783-009-0025-4

摘要： This investigation was carried out to establish a new domestic landfill gas (LFG) generation rate model that takes into account the impact of leachate recirculation. The first-order kinetics and two-stage reaction (FKTSR) model of the LFG generation rate includes mechanisms of the nutrient balance for biochemical reaction in two main stages. In this study, the FKTSR model was modified by the introduction of the outflow function and the organic acid conversion coefficient in order to represent the in-situ condition of nutrient loss through leachate. Laboratory experiments were carried out to simulate the impact of leachate recirculation and verify the modified FKTSR model. The model calibration was then calculated by using the experimental data. The results suggested that the new model was in line with the experimental data. The main parameters of the modified FKTSR model, including the LFG production potential (), the reaction rate constant in the first stage (), and the reaction rate constant in the second stage () of 64.746 L, 0.202 d, and 0.338 d, respectively, were comparable to the old ones of 42.069 L, 0.231 d, and 0.231 d. The new model is better able to explain the mechanisms involved in LFG generation.

关键词： landfill gas (LFG)     generation rate model     first-order kinetics     two-stage reaction     outflow function    

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Exergy analysis of multi-stage crude distillation units

Xingang LI, Canwei LIN, Lei WANG, Hong LI

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 437-446 doi: 10.1007/s11705-013-1349-y

摘要： This paper aims to investigate the multi-stage effect on crude distillation units (CDUs) in thermodynamics. In this regard, we proposed three-, four-, five-, and six-stage CDU processes with all variables constrained to be almost the same except for the number of stages. We also analyzed the energy and exergy to assess the energy consumed by each process. Because additional distillation units would share the processing load and thus prevent products with low boiling points from overheating, the heat demand of the CDUs decreases with increasing stages and thus reduces the heat supply. Exergy loss is considered as a key parameter to assess these processes. When the exergy losses in heat exchangers are disregarded, the three- and four-stage CDUs have lower exergy losses than the five- and six-stage CDUs. When the overall exergy losses are considered, the optimum number of stages of CDUs depends on the exergy efficiency of heat integration.

关键词： exergy     exergy loss     crude oil distillation     multi-stage     energy saving    

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Discussion on back-to-back two-stage centrifugal compressor compact design techniques

Lei HUO, Huoxing LIU

《机械工程前沿（英文）》 2013年 第8卷 第4期   页码 390-400 doi: 10.1007/s11465-013-0278-2

摘要：

Design a small flow back-to-back two-stage centrifugal compressor in the aviation turbocharger, the compressor is compact structure, small axial length, light weighted. Stationary parts have a great influence on their overall performance decline. Therefore, the stationary part of the back-to-back two-stage centrifugal compressor should pay full attention to the diffuser, bend, return vane and volute design. Volute also impact downstream return vane, making the flow in circumferential direction is not uniformed, and several blade angle of attack is drastically changed in downstream of the volute with the airflow can not be rotated to required angle. Loading of high-pressure rotor blades change due to non-uniformed of flow in circumferential direction, which makes individual blade load distribution changed, and affected blade passage load decreased to reduce the capability of work, the tip low speed range increases.

关键词： back-to-back     two-stage     centrifugal compressor     design     Internal flow    

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Simulating multiphase flow in a two-stage pusher centrifuge using computational fluid dynamics

Chong PANG, Wei TAN, Endian SHA, Yuanqing TAO, Liyan LIU

《化学科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 329-338 doi: 10.1007/s11705-012-1205-5

摘要： The design of two-stage pusher centrifuges have developed rapidly, but a good understanding of the theory behind their practice is a long-standing problem. To better understand centrifugal filter processes, the computational fluid dynamics (CFD) software program FLUENT has been used to model the three-dimensional geometry and to simulate multiphase flows based on Euler-Euler, moving mesh, dynamic mesh and porous media models. The simulation tangential velocities were a little smaller than those for rigid-body motion. In the stable flow region, the radial velocities were in good agreement with the theoretical data. Additionally, solid concentration distribution were obtained and also showed good agreement with the experimental data. These results show that this simulation method could be an effective tool to optimize the design of the two-stage pusher centrifuge.

关键词： two-stage pusher centrifuge     multiphase flow     CFD     dynamic mesh     porous media    

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Sustainability performance analysis of environment innovation systems using a two-stage network DEA model

《工程管理前沿（英文）》   页码 425-438 doi: 10.1007/s42524-022-0205-5

摘要： The term environmental innovation system refers to an innovation network composed of enterprises, universities, and research institutions involved in the development and diffusion of environmental technology, with the participation of a government. An environmental innovation system not only exerts important impact on the achievement of carbon neutrality but also affects social and economic activities. Investigations on environmental innovation system performance constantly assume a single-stage independent system while ignoring its internal structure. However, such systems are composed of environmental innovation research and development (R&D) and environmental innovation conversion subsystems. A two-stage data envelopment analysis (DEA) model is developed in this study to analyze the efficiency of Chinese regional environmental innovation system by opening the “black box” and considering shared resources. Empirical results indicated that China presents high overall environmental innovation efficiency although some regions need to improve. Regions with low efficiencies in both environmental innovation R&D (EIR) and environmental innovation conversion (EIC) subsystems should expand their investment in and strengthen the management of environmental innovation resources. Regions with low EIR efficiency should improve the absorption and transformation of environmental innovation achievements. Regions with low EIC efficiency should increase investment in the commercialization of environmental innovation achievements and encourage green economy industries, such as new energy, art, tourism, and environmental protection.

关键词： data envelopment analysis     environmental efficiency     environmental innovation system     shared resources     two-stage structure    

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Removal of odors and VOCs in municipal solid waste comprehensive treatment plants using a novel three-stage

《环境科学与工程前沿（英文）》 2021年 第15卷 第3期 doi: 10.1007/s11783-021-1421-7

摘要：

A novel three-stage integrated biofilter (TSIBF) composed of acidophilic bacteria reaction segment (ABRS), fungal reaction segment (FRS) and heterotrophic bacteria reaction segment (HBRS) was constructed for the treatment of odors and volatile organic compounds (VOCs)from municipal solid waste (MSW) comprehensive treatment plants. The performance, counts of predominant microorganisms, and bioaerosol emissions of a full-scale TSIBF system were studied. High and stable removal efficiencies of hydrogen sulfide, ammonia and VOCs could be achieved with the TSIBF system, and the emissions of culturable heterotrophic bacteria, fungi and acidophilic sulfur bacteria were relatively low.

关键词： Biofiltration     Multi-stage biofilter     Volatile organic compounds     Waste gas treatment     Bioaerosol emissions    

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Mechatronic design of a novel linear compliant positioning stage with large travel range and high out-of-plane

Hua LIU, Xin XIE, Ruoyu TAN, Lianchao ZHANG, Dapeng FAN

《机械工程前沿（英文）》 2017年 第12卷 第2期   页码 265-278 doi: 10.1007/s11465-017-0453-y

摘要：

Most of the XY positioning stages proposed in previous studies are mainly designed by considering only a single performance indicator of the stage. As a result, the other performance indicators are relatively weak. In this study, a 2-degree-of-freedom linear compliant positioning stage (LCPS) is developed by mechatronic design to balance the interacting performance indicators and realize the desired positioning stage. The key parameters and the coupling of the structure and actuators are completely considered in the design. The LCPS consists of four voice coil motors (VCMs), which are conformally designed for compactness, and six spatial leaf spring parallelograms. These parallelograms are serially connected for a large travel range and a high out-of-plane payload capacity. The mechatronic model is established by matrix structural analysis for structural modeling and by Kirchhoff’s law for the VCMs. The sensitivities of the key parameters are analyzed, and the design parameters are subsequently determined. The analytical model of the stage is confirmed by experiments. The stage has a travel range of 4.4 mm× 7.0 mm and a 0.16% area ratio of workspace to the outer dimension of the stage. The values of these performance indicators are greater than those of any existing stage reported in the literature. The closed-loop bandwidth is 9.5 Hz in both working directions. The stage can track a circular trajectory with a radius of 1.5 mm, with 40 mm error and a resolution of lower than 3 mm. The results of payload tests indicate that the stage has at least 20 kg out-of-plane payload capacity.

关键词： mechatronic design     linear compliant positioning stage     large travel range     high out-of-plane payload capacity     spatial parallelogram     voice coil motor     sensitivity analysis    

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Development of a novel two-stage proportional valve with a pilot digital flow distribution

Qiang GAO, Yuchuan ZHU, Changwen WU, Yulei JIANG

《机械工程前沿（英文）》 2021年 第16卷 第2期   页码 420-434 doi: 10.1007/s11465-020-0622-2

摘要： Pilot two-stage proportional valves are widely used in high-power hydraulic systems. For the purpose of improving the dynamic performance, reliability, and digitization of the traditional proportional valve, a novel two-stage proportional valve with a pilot digital flow distribution is proposed from the viewpoint of the dual nozzle-flapper valve’s working principle. In particular, the dual nozzle-flapper is decoupled by two high-speed on/off valves (HSVs). First, the working principle and mathematical model of the proposed valve are determined. Then, the influences of the control parameters (duty cycle and switching frequency) and structural parameters (fixed orifice’s diameter and main valve’s spring) on the main valve’s motion are analyzed on the basis of theory, simulation, and experiment. In addition, in optimizing the value of the fixed orifice’s diameter, a new design criterion that considers the maximum pressure sensitivity, flow controllability, and flow linearization is proposed to improve the balance between the effective displacement and the displacement fluctuation of the main valve. The new scheme is verified by simulations and experiments. Experimental results of the closed-loop displacement tracking have demonstrated that the delay time of the main valve is always within 3.5 ms under different working conditions, and the tracking error can be significantly reduced using the higher switching frequency. The amplitude–frequency experiments indicate that a ‒3 dB-frequency of the proposed valve can reach 9.5 Hz in the case of±50% full scale and 15 Hz in the case of 0%–50% full scale. The values can be further improved by increasing the flow rate of the pilot HSV.

关键词： two-stage proportional valve     digital flow distribution     high-speed on/off valve     position tracking characteristic     dynamic performance    

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Scaling up a novel denitrifying microbial fuel cell with an oxic-anoxic two stage biocathode

Peng LIANG, Jincheng WEI, Ming LI, Xia HUANG

《环境科学与工程前沿（英文）》 2013年 第7卷 第6期   页码 913-919 doi: 10.1007/s11783-013-0583-3

摘要： A scaled up microbial fuel cell (MFC) of a 50 L volume was set up with an oxic-anoxic two-stage biocathode and activated semicoke packed electrodes to achieve simultaneous power generation and nitrogen and organic matter removals. An average maximum power density of 43.1 W·m was obtained in batch operating mode. By adjusting the two external resistances, the denitrification in the A-MFC and power production in the O-MFC could be enhanced. In continuous mode, when the hydraulic retention times were set at 6 h, 8 h and 12 h, the removal efficiencies of COD, and total nitrogen (TN) were higher than 95%, 97%, and 84%, respectively. Meanwhile the removal loads for COD, and TN were10, 0.37 and 0.4 kg·(m ·d) , respectively.

关键词： microbial fuel cell (MFC)     oxic-anoxic two stage biocathode     denitrifying    

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标题 作者 时间 类型 操作

High-bandwidth nanopositioning via active control of system resonance

Linlin LI, Sumeet S. APHALE, Limin ZHU

期刊论文

Preload characteristics identification of the piezoelectric-actuated 1-DOF compliant nanopositioning

Ruizhou WANG, Xianmin ZHANG

期刊论文

Compressor performance of two-stage turbocharging system

HE Yituan, MA Chaochen, WEI Mingshan, ZHU Zhifu, HE Yituan

期刊论文

以电子方式提升洛伦兹力驱动器的大行程纳米定位精度

Bimal Jeet GOTEEA,张前军,董为

期刊论文

Two-stage stochastic programming with robust constraints for the logistics network post-disruption response

期刊论文

Efficiency measurement for mixed two-stage nonhomogeneous network processes with shared extra intermediate

Qingxian AN, Xuyang LIU, Shijie DING

期刊论文

Modified landfill gas generation rate model of first-order kinetics and two-stage reaction

Jiajun CHEN , Hao WANG , Na ZHANG ,

期刊论文

Exergy analysis of multi-stage crude distillation units

Xingang LI, Canwei LIN, Lei WANG, Hong LI

期刊论文

Discussion on back-to-back two-stage centrifugal compressor compact design techniques

Lei HUO, Huoxing LIU

期刊论文

Simulating multiphase flow in a two-stage pusher centrifuge using computational fluid dynamics

Chong PANG, Wei TAN, Endian SHA, Yuanqing TAO, Liyan LIU

期刊论文

Sustainability performance analysis of environment innovation systems using a two-stage network DEA model

期刊论文

Removal of odors and VOCs in municipal solid waste comprehensive treatment plants using a novel three-stage

期刊论文

Mechatronic design of a novel linear compliant positioning stage with large travel range and high out-of-plane

Hua LIU, Xin XIE, Ruoyu TAN, Lianchao ZHANG, Dapeng FAN

期刊论文

Development of a novel two-stage proportional valve with a pilot digital flow distribution

Qiang GAO, Yuchuan ZHU, Changwen WU, Yulei JIANG

期刊论文

Scaling up a novel denitrifying microbial fuel cell with an oxic-anoxic two stage biocathode

Peng LIANG, Jincheng WEI, Ming LI, Xia HUANG

期刊论文