Piezo-actuators modeling for smart applications

This paper deals with piezoelectric actuators modeling. The objective is to contribute in piezo-models library construction. Compared to existing models in commercial packages, the proposal model integrate nonlinear effects, especially hysteresis, while not requiring high computing efforts. This will help in the generalization of piezo-actuator usage for smart applications. Our methodology and approaches are clearly justified in the paper.     

一种无需ADC的变步长反馈DC-DC 转换器数控方式

数控DC-DC变换器由于其自身的特点,易于与数字系统进行单片集成.DC-DC的数字控制算法有很多种,其中比较复杂的算法(如PID)需要在片内集成ADC,增加了设计难度.较为简单的控制方案只使用单一的比较器作为反馈输入部件,但动态性能较差.本文在已有的单比较器恒定步长反馈数控Buck转换器的基础上,提出了一类变步长反馈的方案.由于仍使用单比较器或窗口比较器,它的结构简单且易于集成.它借鉴了对分搜索的思路,能根据输出电压反馈的结果动态地改变占空比的变化步长,从而明显地提高了原有恒定步长反馈数控变换器的动态性能.     

A method for partitioning applications in hybrid reconfigurable architectures

In this paper, we propose a methodology for accelerating application segments by partitioning them between reconfigurable hardware blocks of different granularity. Critical parts are speeded-up on the coarse-grain reconfigurable hardware for meeting the timing requirements of application code mapped on the reconfigurable logic. The reconfigurable processing units are embedded in a generic hybrid system architecture which can model a large number of existing heterogeneous reconfigurable platforms. The fine-grain reconfigurable logic is realized by an FPGA unit, while the coarse-grain reconfigurable hardware by our developed high-performance data-path. The methodology mainly consists of three stages; the analysis, the mapping of the application parts onto fine and coarse-grain reconfigurable hardware, and the partitioning engine. A prototype software framework realizes the partitioning flow. In this work, the methodology is validated using five real-life applications. Analytical partitioning experiments show that the speedup relative to the all-FPGA mapping solution ranges from 1.5 to 4.0, while the specified timing constraints are satisfied for all the applications.     

The benefits of interdisciplinary scenario-building for hybrid radio applications

In this paper, we make the case for building interdisciplinary scenarios, integrating technological, business and user perspective during the fuzzy front-end of innovation. We start from a living lab framework, underpinning the iterative process to integrate insights from all three perspectives within research projects. Then, we explain how the approach was applied within the HRADIO project¹. This EU funded project focuses on the development of hybrid radio applications. We demonstrate how the process of building interdisciplinary scenarios and the involvement of multiple perspectives to evaluate these scenarios, has enabled both strategic decision making (1) and improved the technical development process within the HRADIO project (2). The first focuses on the (lack of) interest in certain scenarios from a business, technology and/or user perspective, to explain: (a) how these thresholds can be overcome and (b) what the consequences are for the project. The latter explains how we moved from interdisciplinary scenarios to a first Minimum Viable Product (MVP) that could be tested in the first pilot phase, to prototypes to be tested in the second pilot phase. To validate the importance of the scenarios, we also explain how the scenarios are integrated into the exploitation timeline. Finally, and importantly, we address how the process of multidisciplinary scenario building and evaluation can be improved.     

高可靠航空永磁无刷直流电机伺服控制系统设计

本文针对航空机电作动器高可靠性要求,设计了一套永磁无刷直流电机伺服控制系统,详细介绍了系统构型、关键参数设计和保护电路设计。采用电气隔离方式,实现了电机功率驱动部分和算法控制部分的隔离,抑制了故障蔓延。通过设计电机过/欠压保护、电流保护和软启动保护工作机制,实现了电机驱动的高可靠性工作。实验结果表明,本文设计的永磁无刷直流电机伺服控制系统功能性能完善、信号采集精度高、电机保护机制完备,具有很高的可靠性和实用性。     

基于DSPIC的工业控制系统的设计

介绍了一套基于直流无刷电机的工业缝纫机控制系统的设计与实现,该系统特点是以霍尔信号的位置和电机的速度进行估算,并在此基础上实现对直流无刷电机的方波控制。给出了控制系统硬件和软件的实现方法。实验结果表明：该系统的生产成本比较低,也能够满足工业缝纫机的调速范围大、动态性能好等技术指标。     

开放平台下调速系统模糊控制的教学实践

本文介绍了基于开放式计算机控制直流调速系统教学实验平台,指导学生在传统PID调节器中加入模糊控制策略的教学实践.笔者分析了Matlab/SimuIink软件环境下参数在线自整定模糊PID控制器的设计过程,并对比分析了不同控制策略实验结果.开发的实验装置新功能可以有效提升实验教学水平.     

基于事件触发通信的分布式直流微电网容错控制

本文针对分布式微电网系统,为了解决系统的执行器故障和通信信息冗余的问题,设计出事件触发机制和鲁棒性容错控制策略。为了优化系统之间通信信道过程中数据传输量,提出该事件触发机制,采用事件状态反馈更新控制输入来减轻通信负担;此外,针对系统的内部执行器故障和外部扰动因素,设计鲁棒容错控制器,采用故障矩阵凸包法来保证系统的稳定性。通过构造Lyapunov函数技术设计的事件触发条件来确保系统的稳定性,并在保持系统性能的情况下,使用此策略可实现全局平均电压调节,按比例分配负载。所提出的控制策略在MATLAB/SIMULINK环境中进行了仿真,并验证容错控制器的有效性。     

Split ring resonator based multiband hybrid fractal antennas for wireless applications

In this paper, initially two Moore Antennas are designed which are different from each other in terms of 50 Ω microstrip transmission line only. Same size Feed line is applied at right and left side of the substrate and termed as Left Side Feed Line (LFL) and Right Side Feed Line (RFL). To improve the multiband behavior of Moore Antenna, it is being fused with Koch curve and resultant antenna is named as Moore – Koch Hybrid Fractal Antenna (MKHFA) where Koch curves are superimposed on Moore curve. Two distinct MKHFA’s are designed as MKHFA with LFL and MKHFA with RFL. In order to attain the more number of frequency bands, improved gain, better impedance matching and improved bandwidth, both the MKHFA’s are loaded with Split Ring Resonator (SRR). Proposed antennas are designed on FR4 glass epoxy substrate with thickness 1.6 mm, relative permittivity 4.4. Results of Moore Antenna has been compared with MKHFA and found that MKHFA exhibits multiband behavior. A comparison between unloaded MKHFA using LFL/RFL and loaded MKHFA using LFL/RFL has been made and found that later case exhibits better results in terms of increase in number of frequency bands, bandwidth enhancement and improvement in gain. Prototypes of proposed MKHFA using LFL loaded with SRR and MKHFA using RFL loaded with SRR have been fabricated and tested for their results. The comparison between the simulated and measured results have been done and found in good agreement with each other. The overall dimensions of proposed MKHFA using LFL/RFL loaded with SRR is 25 mm × 25 mm and can be useful for different wireless applications such as Bluetooth (2.41–2.49 GHz) for ISM band, IEEE 802.11 g/b (2.40–2.48 GHz), WiMAX (2.5–2.69 GHz), WLAN (5.15–5.35 GHz), X-band satellite communication (7.1–7.76 GHz). Proposed MKHFA using LFL loaded with SRR also reports peak gain 5.76 dB and bandwidth 770 MHz, whereas, MKHFA using RFL loaded with SRR confirms peak gain 8.56 dB and bandwidth 750 MHz.     

Shear-mode PMN-PT piezoelectric single crystal resonator for microfluidic applications

We report on the integration of a PMN-PT single crystal-based piezoelectric resonator in a microfluidic system. In this experiment, the resonator was implanted in the microfluidic channel through a standard soft lithography process with its top electrode in contact with the flowing fluid. The results showed that, activated in shear mode, the resonator sensed changes occurring along the fluid-electrode interface and gave responses in the form of impedance resonance frequency shift. By measuring the frequency shift, changes in the fluidic property (e.g. viscosity) could be monitored. Examples are given to demonstrate the potential use of the system for cell detections.     

Hybrid fuzzy-logic and neural-network controller for MIMO systems

This study developed a hybrid fuzzy-logic and neural-network controller (HFNC) for multiple-input multiple-output (MIMO) systems. The HFNC consists of a fuzzy logic controller (FLC) which was designed to control each degree of freedom (DOF) of a MIMO system individually and an additional coupling neural network which was incorporated into the FLC to compensate for the dynamic coupling effects between each DOF of the MIMO system. Stability and robustness of the HFNC have been demonstrated using a state-space approach. From the simulation results of the 2-link robotic manipulator application and the experimental results of the 6-DOF robot tests, the HFNC demonstrated more superior control performance than the FLC.     

基于8位微控制器的参数自调整模糊控制DC/DC变换器

提出了一种基于8位微控制器实现的用于控制DC／DC变换器输出电压的参数自调整模糊控制方法。用参数自调整的策略来优化常规模糊控制器，提高了DC／DC变换器的控制性能。实验结果表明，所提出的新控制方法不仅具有良好的控制性能，而且容易用成本较低的8位微处理器来实现。     

Highly transparent polyimide/nanocrystalline-zirconium dioxide hybrid materials for organic thin film transistor applications

A solution-processable high k dielectric materials based on polyimide/zirconium dioxide (PI-ZrO₂) for organic thin film transistors (OTFTs) is demonstrated. To study the effect of the ZrO₂ content on the properties of the dielectric layer, a series of PZn films (n = 0, 2, 5, 8, 10, 12, and 15, which are the weight percentage of ZrO₂ in the film) were prepared. The results showed that all of the prepared hybrid films had a high transmittance of 96–99%. The nondestructive Zr K-edge XANES analysis revealed that the absorption intensity was proportional to the ZrO₂ content. EXAFS analysis indicated that the ZrO₂ formed bigger clusters in the film than in the solution state. Water and diiodomethane contact angle analysis found that the PZ12 film had the largest contact angles, lowest surface energy, and lowest water absorbance, which results in the least structural defects and highest carrier mobility. Electrical property analysis indicated that the dielectric constant of the films increased from 4.04 for the PZ0 film to 8.10 for the PZ12 film, but then dropped for the PZ15 film. All current leakages (−2 MV/cm) were less than 10⁻⁹ A/cm. The carrier mobility in the PZ0 film was 2.78 × 10⁻¹, up to 4.15 × 10⁻¹ for the PZ12 film, but down to 3.34 × 10⁻¹ for the PZ15 film. The I_on/I_off ratio was 2.3 × 10³ for PZ0, up to 1.4 × 10⁵ for PZ12, but down to 1.8 × 10⁴ for PZ15. The hybrid dielectric devices showed better performance. This work reveals great potential for hybrid dielectric materials for OTFT applications.     

DC/DC变换器自适应模糊逻辑控制器设计

文章为DC/DC变换器设计了一种自适应模糊逻辑控制器（AFLC）。所提出的AFLC不需要专家系统提供决策参数和控制规则,而是使用模型数据文件来产生参数和规则,该模型数据文件包含输入输出对的整体概况。所提出的控制器使用8位微控制器来实现降压、升压和降压-升压变换器。     

基于DSP直流电机速度的模糊控制系统研究

介绍一种基于模糊控制的直流电机速度控制系统。该模糊控制器设计为二维模糊控制器,以速度反馈和给定转速的误差及误差的变化率作为模糊控制器的输入变量,采用带调整因子的模糊控制器不需要建立模糊查询表。运用DSP强大的计算能力直接按实时计算输出控制量,实现编码器的解码、速度的测量。试验表明系统具有较强的鲁棒性和抗干扰能力,适应于各种不同的场合。     

无刷直流电动机离散变结构控制器设计与仿真

介绍了无刷直流电动机（BLDCM）位置伺服系统离散时间变结构控制器的设计方法。数字仿真结果表明：变结构控制器具有健全的控制性能，对控制对象的参数变化及外部扰动并不敏感，系统状态将按预定的路径变化，因而伺服系统具有高稳定性、高精度、鲁棒性和快速响应等优点。     

火炮随动系统多目标优化控制

给出了采用X-Q自适应控制器构成的一类非线性控制器以及实现多目标优化控制系统的计算机辅助设计参数寻优方法,讨论怎样应用X-Q自适应控制器实现多目标优化控制,并给出实现多目标优化火炮随动控制系统的实例,计算机仿真校验其性能指标的结果表明,多目标优化系统的性能指标好,设计方法简单、通用、适用于工程设计。     

A hybrid chaotic map for communication security applications

Recently, the synchronization between two matching chaotic systems to provide confident communication has gained a lot of interest. Continuously, there is a necessity to produce a novel dynamical system to be used in synchronization to implement a strong security system. In this paper, a hybrid chaotic system is suggested and verified for the potential use of secure communication through chaos synchronization. The Lyapunov exponent (LE) and zero‐one (0‐1) tests have been used to verify the performance of the suggested hybrid chaotic system, while National Institute of Standard and Technology (NIST) tests have been applied to verify the randomness properties. And the synchronization has been achieved between master and slave systems by using nonlinear control laws. The simulation outcomes demonstration that the hybrid system has chaotic performance and outstanding randomness characteristic. The statistical results gained for LE test was 0.8822, and for frequency test (FT) was 0.2028, while for the run test (RT) was 0.1924. Accordingly, the suggested hybrid system can be used to evolve functional synchronization algorithms and encryption for image, video, and voice secure communication applications.     

新型混合动力电动船的发展现状浅析

"混合动力电动船"是利用能量转换器将两种或者两种以上的能量源的能力转换成电能作为船舶的主要动力源的船只.本文主要介绍了一种风光能、电能互补的混合动力电动船,将其与原有柴油驱动电动船作比较,并对其现在发展受制约的原因进行分析,为接下来进一步对其改造选定方向.     

All inkjet-printed piezoelectric polymer actuators: Characterization and applications for micropumps in lab-on-a-chip systems

Digital printing technologies are promising as future manufacturing approaches due to their capabilities of highly flexible and additive material deposition on various substrates. In this contribution, all inkjet-printed piezoelectric polymer actuators are presented based on polyvinylidene fluoride trifluoroethylene (P(VDF-TrFE)) and electrodes printed from silver nanoparticle dispersions. The target application for the actuators described here are membrane pumps for microfluidic lab-on-a-chip (LOC) systems. For the first time, all-inkjet-printed P(VDF-TrFE) actuators are reported and the corresponding piezoelectric d₃₁ coefficient is measured. For manufacturing the actuators, a low-cost procedure is employed that consists of only three inkjet printing and post-processing steps where moderate thermal treatments (T_max = 130 °C) are combined with plasma sintering. The processing is therefore compatible with a wide range of temperature sensitive polymer substrates, completely additive and highly flexible. A sandwich-like structure of a piezoelectric P(VDF-TrFE) layer between two silver electrodes is inkjet-printed onto a polyethylene terephthalate (PET) substrate. When a voltage is applied across the piezoelectric layer, the reverse piezoelectric effect will lead to a bending deflection of this unimorph structure. The piezoelectric d₃₁ coefficients are found to be approximately 7 to 9 pm V⁻¹, which allows the generation of significant actuator deflections. For the application in a micropump, flow rates of several 100 μL min⁻¹ are anticipated, which is promising for LOC applications. Most current micropumps are based on actuator elements that are fabricated separately and mounted on a passive membrane. By using all inkjet-printed actuators, as presented here, the joining step is avoided and the benefits of low-cost printed devices are added to the well-developed processing approaches for microfluidic chips.