铂型离子聚合物金属复合材料传感特性

基于不可逆热力学和薄板大挠度理论建立了大挠度状态下的IPMC的传感模型。即以不可逆热力学理论为基础,描述了IPMC的离子输运内在机理,以及离子运动与电场及浓度差之间的关系,并考察了IPMC内部的离子运动形式,建立电场与内部压力差之间的关系;同时通过分析受外载荷作用后发生大挠度情况下压力与挠度之间的关系,建立IPMC在大挠度时曲率与两金属膜之间形成的电势差之间的关系,即给出了大挠度状态下IPMC的传感性能模型,并分析了IPMC输出电压的影响因素。将模型仿真值与实验结果进行对比,误差在25%以内,说明建立的传感模型能够较好的预测大挠度状态下IPMC受载后的输出电压。研究结果也表明环境因素对IPMC传感性能的影响很大,在一定程度上限制了其应用范围。     

离子聚合物金属复合材料电学性能研究

建立了电流测试平台,并对不同IPMC进行电流测试分析,为IPMC材料的改性提供依据。选用TBC0.5A02电流传感器设计电路,采用NI PCI-6024E数据采集卡,通过LabVIEW程序编写采集程序,并对采集到的电流传感器的输出信号进行处理。将固定电压施加在一系列固定的电阻上,从而建立电流传感器输出值和输入值的关系,实现实时测量流经IPMC的电流。通过比较商业膜基体IPMC、自制膜基体IPMC以及TEOS改性膜基体IPMC在不同正弦电压信号下的电流值,证明该测试系统是可行的。     

大功率IPMC驱动电路的设计

设计了一种用于IPMC电制动聚合物的驱动电路,该驱动电路能够提供IPMC低频双极性的可程控信号,输出信号的功率可以达到2W,具有很强的带电流能力。控制系统的主控芯片为AT-mega16单片机,外部电路包括D/A数模转换模块、信号发生模块和信号放大模块3大部分。设计了输出信号的控制软件,可以输出方波、三角波、正弦波和组合波形。通过将该控制系统与信号发生器驱动IPMC的输出结果进行比较,进一步验证了控制系统的可行性。     

基于目标跟踪的IPMC测控系统设计

针对IPMC驱动和性能测试的需求,设计了一种IPMC测控系统。控制系统以STM32F103RET6为主控芯片,可输出双极性大电流的正弦波、方波和组合波形,并且输出信号的幅值、频率和占空比可调;位移检测系统基于Lab VIEW的MeanShift目标跟踪算法,可对IPMC末端进行目标跟踪,并实时显示其在两个方向上的位移。利用该测控系统进行IPMC性能测试实验,验证了其可行性。     

气体动载荷下压电振子能量转化特性实验研究

针对当前利用化学电池为传感器供能具有的使用时间短及污染环境等问题，提出了一种可应用于气动系统中气体动载荷环境的能量转化与收集装置。利用压电材料的正压电效应对压电振子发电机理进行分析，分析结果表明，在气体动载荷激励下输出电能与压力变化量呈正比。仿真分析了压电振子所在容腔的内部流场变化，并分析了腔内压力及压力变化量随时间的变化规律。结合理论研究与仿真分析设计并制作了一种压电振子能量转化实验样机，搭建了实验测试系统。以动态气体载荷为激励源对不同流量、周期及负载条件的改变进行了实验测试。实验结果表明随着距离的增加，压电振子的输出电压逐渐下降；随着流量的增加峰值电压增加，当周期为1.2 s、流量为200 L/min、压力为0.3 MPa时最大的输出电压为79.60 V。     

人工肌肉作动器的制备及其视觉测控系统研究

为制作离子聚合物一金属复合材料（IPMC）,基于全氟磺酸液制出厚达0．5mm基体膜,在利用还原法在膜表沉积出铂电极后,制成动力达22．5mN的IPMC。研制出IPMC视觉测控系统,并通过视觉采集部件捕捉其电致动图像,引入区域平均法和Roberts算子进行图像滤噪与锐化,采用灰度阈值法从图像中分割出IPMC轮廓并提取其末端位移。设计出IPMC控制电路,进行了IPMC功能特性与控制实验。研究表明,增大IPMC膜厚可增大其输出动力,采用PI控制可使IPMC末端位置跟踪误差控制在±0．5mm之内。     

直流电激励下的IPMC弯曲大变形力-电耦合模型

为了描述离子聚合物金属复合材料(ionic polymer metal composites, 简称IPMC)悬臂型驱动器在直流电激励下的非线性大变形行为,采用数字图像相关法(digital image correlation, 简称DIC)获得的IPMC应变梯度与激励电压间的关系,与修正后的IPMC电极分布式电阻电容（resistor-capacitor, 简称RC）电路模型相结合,提出了一种具有解析解的IPMC弯曲大变形力-电耦合模型,并采用Pt电极和Ag电极两种IPMC试样对该模型进行了实验验证。结果表明,该模型能够准确地反映IPMC悬臂型驱动器在直流电激励下的整体弯曲变形现象,且适用于采用沉积法制备电极的IPMC驱动器。     

磁致伸缩触觉传感单元及其输出特性

为了满足机器人精确感知和抓取物体的需要,首先设计了以铁镓丝为敏感元件的新型触觉传感单元,搭建了传感单元输出特性测试平台,测试了其输出电压与施加静态和动态压力的关系。以触觉传感单元为核心设计了传感器阵列结构,并将传感阵列安装在机械手上,进行了抓取实验。实验结果表明,施加静态压力时,在1.908kA/m的偏置磁场下,长度为16mm、直径为0.8mm的铁镓丝组成的触觉传感单元在2N压力下的输出电压可达96mV,灵敏度为48mV/N。在1～4Hz、0～2N的动态压力作用下,传感单元输出曲线平滑,灵敏度高。传感器阵列安装在机械手上,能感知多路压力信息,精确显示机械手指的受力分布情况,可广泛应用在机械手准确抓取与智能控制领域中。     

一种基于强度补偿的自由式光纤束差压传感器

对一种基于强度补偿的自由式光纤束差压传感器进行设计与研究。传感器探头部分采用同结构、双探头的设计,传感器探头采用机械式封装;对传感器的光纤部分进行了强度补偿设计与分析,并利用调制函数M,理论分析了补偿后的输出值R;在对两传感探头施加相等的压力p=20kPa情况下,改变光源的输出功率,测出光电探测器的输出电压值,并在两探头存在不同的压差Δp时,测出其输出值R。实验结果表明：通过强度补偿后,输出值R≈1,同时在不同的压差作用下,输出值R与压差Δp在一段区域内有较好的线性关系。研究结果表明：传感器的强度补偿效果明显,可实现压力差值的检测。     

变拓扑LLC变换器的均流均压控制研究

隔离型变换器在新能源汽车充电和服务器电源得到广泛应用，传统LLC谐振变换器虽然具有高效率和高功率密度等优点，但传统LLC变换器在重载区的升压增益能力有限。提出一种变结构LLC变换器拓扑，通过分析变频控制加辅助移相补偿的工作原理来了解变换器的工作特性。并以此为基础进行参数和控制设计，使其能达到LLC谐振变换器的软开关特性和宽输出电压范围内连续调节的能力。最后设计了一台实验样机，验证了LLC变换器具有良好的宽输出电压范围能力，且串并联切换能实现均流均压控制目的。     

Preparation and performance of soft actuator based on IPMC with silver electrodes

The surface electrodes of traditional ionic polymer-metal composites (IPMC) are made of platinum. To reduce the production cost, nonprecious metals such as silver is proposed. A new approach of electroless silver plating based on chemical deposition method is adopted, getting two types of IPMCs, Pt-Ag IPMC, and Ag-Ag IPMC. The microscopic analysis, driving abilities tests, and their surface-electrode resistance analysis show that Ag and Pt particles penetrate inside Nafion membrane with gradient distribution throughout the membrane. The maximum electro-active bending deformation angles of the specimens, which are obtained under the same specimen dimension and constrains, are about 60° for Pt-Pt IPMC and Pt-Ag IPMC and 90° for the Ag-Ag IPMC, respectively, corresponding to the driving voltage of 3 V, 4 V, and 1.5 V. The surface-electrode resistance of Ag-Ag IPMC is the lowest and the most stable, which shows that the proposed approach is valid. The experiments show that the IPMC technology based on the silver electrode is feasible.     

基于C8051F的交流功率放大系统

以C8051F单片机为核心的交流功率放大系统的设计,采用C8051F内部的电压方式D/A转换器输出0～1V的正弦波,用于控制功率放大器输出电压按设定值变化.同时功率放大系统具有过流保护、过压保护与过热保护功能、输出电压稳定、带载能力强、控制精度高等特点.     

一种新型硅压阻式流速流向传感器的设计

本文设计了一种基于体微机械加工技术、SU-8-光刻胶工艺和压阻检测的新型硅压阻式流速流向传感器.该传感器由立柱和支撑梁构成,这种结构将流体的流速流向信息转化为立柱的倾斜和相应的梁的变形,通过4根正交梁端部的压阻应变计来测量梁的变形.通过测量压电电阻的阻值变化就可以得到流体的流速和流向.利用惠斯通电桥来获得正弦电压输出.理论分析了器件的结构变形和电压输出,并用有限元方法进行了验证.为该传感器设计了一套基于键合技术的体微机械加工工艺.     

A study on the control of an IPMC actuator using an adaptive fuzzy algorithm

The Ionic Polymer Metal Composite (IPMC) is one of the electroactive polymers (EAP) that was shown to have potential application as an actuator. It bends by applying a low voltage current (1–3 V) to its surfaces when containing water. In this paper, the basic characteristics and the static & dynamic modeling of IPMC is discussed. In modeling and analysis, the equations of motion, which describe the total dynamics of the system, are driven. To control the position of the IPMC actuator, an adaptive fuzzy algorithm is used. IPMC is a time varying system because the some parameters vary with the passage of time. In this paper, the modeling and control of IPMC is introduced.     

Performance of ionic polymer-metal composite (IPMC) with different surface roughening methods

Based on permeation and double chemical reduction technology, this paper researches the manufacture of Pt-ionic polymer metal composites (IPMC) and the effect of three types of surface roughening methods on the manufacture and performance of IPMC. The roughening methods include manual polishing, sanding machine polishing, and plasma surface treatment. The appearance and scanning electron microscopy (SEM) features, electro-active deformation and surface resistance characteristics of these IPMC specimens were obtained and compared through specimen tests. The results of the tests indicate that surface roughening technology obviously influences the performance of IPMC. The uniformity and compactness of the metal deposited on the surface and inside the Nafion film are improved by improving surface roughening uniformity. However, the electro-active deformation capability and surface resistance of the specimens decrease at the same time. There is an approximate linear increase relationship between the driving voltage and the bending deformation of the IPMC specimen within a certain voltage range. Under the same specimen dimension, constraints, and driving voltage (3V), the maximum electro-active bending deformation angles of the specimens are about 60°, 45°, and 15° for manual polishing, sanding machine roughening, and plasma treatment, respectively.     

Performance of ionic polymer-metal composite (IPMC) with different surface roughening methods

Based on permeation and double chemical reduction technology, this paper researches the manufacture of Pt-ionic polymer metal composites (IPMCs) and the effect of three types of surface roughening methods on the manufacture and performance of IPMC. The roughening methods include manual polishing, sanding machine polishing, and plasma surface treatment. The appearance and scanning electron microscopy (SEM) features, electro-active deformation and surface resistance characteristics of these IPMC specimens were obtained and compared through specimen tests. The results of the tests indicate that surface roughening technology obviously influences the performance of IPMC. The uniformity and compactness of the metal deposited on the surface and inside the Nafion film are improved by improving surface roughening uniformity. However, the electro-active deformation capability and surface resistance of the specimens decrease at the same time. There is an approximate linear increase relationship between the driving voltage and the bending deformation of the IPMC specimen within a certain voltage range. Under the same specimen dimension, constraints, and driving voltage (3 V), the maximum electro-active bending deformation angles of the specimens are about 60°, 45°, and 15° for manual polishing, sanding machine roughening, and plasma treatment, respectively.     

基于TC787和PLC的变频器恒压充电系统

文章分析了变频器对恒压充电的具体要求,给出了基于TC787与PLC结合的设计方案,并以此出发,给出了硬件和软件的总体设计;同时对设计中比较重要的取样电路和比较电路进行了详细的阐述。该系统具有输出电压稳定、纹波小等优点,对变频器组进行预充电的同时能实现自动检测、自动切换功能,为后续的变频器安全启动提供了可靠的保证,实践表明了系统的可靠性和准确性。     

Adaptive feedforward control of ionic polymer metal composites with disturbance cancellation

Ionic polymer-metal composites (IPMCs) are promising candidates in various sensing and actuation applications due to their light weight, large bending, and low actuation voltage requirements. However, IPMCs are still in the early stage of development, and their bending response can vary widely depending on various factors such as fabrication process, water content, temperature, and contact with electrodes. To control IPMCs in a predictable manner and to minimize the effects of plant uncertainty and external disturbances, a precise and robust control scheme is required. In the present work, a three-part adaptive feedforward control architecture is employed for IPMC deflection control. First, adaptive identification is performed to identify changes in the dynamic behavior over time and in the input voltage using a gradient descent method. Second, an adaptive feedforward controller is implemented to control the dynamic response of the plant, where the IPMC displacement is observed and is used to adjust the parameters of the controller. Third, noise and disturbance cancelling is performed using an additional adaptive canceller, which does not affect the system dynamics. Our results show that the adaptive identification and feedforward controller with disturbance cancellation using the gradient descent method provides accurate tracking performance under plant variation and disturbance. Especially, the fast convergence speed of the proposed technique makes it practical for online control.     

IPMC型柔顺手爪作动器的设计与性能测试

为克服传统手爪机构传动链多,耗能大,结构复杂等缺点,设计并制作了一种应用电致动智能材料(IPMC)的柔顺手爪。运用Pro/E软件设计IPMC手爪的主体结构,并分析其运动过程,最终装配完成IPMC手爪;运用激光位移传感器,精密电子秤和Canon相机测试了研制的4片IPMC驱动薄膜的末端位移,端部力和平均运动速度,并通过Labview测试系统对其进行采样和分析。实验结果表明:IPMC手爪驱动元件的角位移在3V电压激励下超过了180°(-3V电压下负向位移与+3V电压下正向位移之和);其末端位移大小为其自身(除固定部分外)总长;手爪驱动薄膜每片重量约为0.5mg,可抓握质量为1.6g左右的物体。该手爪结构简单、位移大、耗能低;同时,由于IPMC的柔顺特性,在抓取物体时它会贴附在其表面,而不破坏其表面精度。因此,这种手爪适用于抓取表面粗糙度要求高的物体。