音圈电机温度特性的实验研究

现代硬盘机和光盘机的定位系统执行机构一般采用音圈电机驱动。定位系统的工作性与音圈电机的性能密切相关。文中测量了音圈电机力矩常了随温度的变化关系，该测量结果对研究音圈电机伺服控制的温度补偿具有重要意义。     

基于正交实验的音圈电机参数权重分析

音圈电机是一种将电能直接转换成机械能的直线电机,采用简单的结构,省去了繁复的传动结构。影响音圈电机出力的有诸多因素,为了分析各项参数对出力大小的影响,该文选择电枢所受电磁力的大小作为评估指标,基于正交分析试验方法得出影响出力大小的主次因素及规律,并分析了各参数的交互作用。分析结果表明,各因素对音圈电机出力大小的敏感度顺序:线圈电流>线圈匝数>气隙,所得结果可为音圈电机仿真提供一种新的思路以及为音圈电机设计优化提供重要依据。     

音圈电机伺服系统的自适应非光滑控制

针对音圈电机伺服系统的轨迹跟踪控制品质受动力学参数不确定性及外部扰动影响的问题,建立动力学模型,结合自适应控制与非光滑控制理论,设计一种自适应非光滑控制方法,并理论证明了闭环系统的渐近稳定性．最后,通过仿真实验及其对比来验证所设计方法的有效性,仿真结果表明,所设计方法具有自适应控制的补偿能力与非光滑控制的快速收敛特性,能够克服不确定性影响,有效提高音圈电机伺服系统的轨迹跟踪控制品质．     

基于铁氧体材料的永磁直线电机电磁性能分析

为了改善长次级永磁同步直线电机在物流仓储产业及相关物流运输、分拣等方面的应用中存在的耗费高的问题,提出了一种高可靠性且造价较低的铁氧体永磁同步直线电机。通过建立电机二维有限元模型,在稀土永磁同步电机优化设计的基础上,将稀土永磁体更改为铁氧体,并分析电机电磁性能。为了提高电机推力,分析了槽深及匝数对电机推力、推力波动及铜耗的影响。该电机可以应用于物流分拣、传输线等场合,可以提高系统和平台的效率,降低建设成本。     

伺服图形光刻机调焦系统音圈电机的设计

本文以作者对光刻机刻蚀光头调焦音圈电机的设计的实际经验为例,阐述了两种音圈电机结构的设计原则。并对这两种音圈电机的性能进行了分析。     

DSP和ARM的音圈电机伺服控制系统设计

给出了一种基于数字信号处理器DSP和嵌入式ARM微处理器的双核架构,采用典型的直流PWM功率驱动电路,构成数字化的音圈电机伺服控制系统的设计方法。DSP主要完成系统初始化、位置环算法计算等;ARM主要完成PWM波产生、A/D采集、以太网通信、与DSP之间的数据交换等。实验结果表明,系统能够满足设计要求。     

高频响下音圈电机迟滞特性的建模与控制

优化数控机床给进定位精度问题,音圈电机(Voice Coil Motor,VCM)在高频、高速、高加速情况下,存在的迟滞特性影响系统的性能特性.为了实现青圈电机的精确定位控制,提出了音圈电机复杂迟滞神经网络动态逆模型的控制方法.首先,建立了音圈电机复杂迟滞神经网络动态模型,根据迟滞的特性求出了音圈电机复杂迟滞神经网络动态逆模型,采用逆模型结合PD控制算法进行仿真.实验结果表明,系统最大跟踪误差减少到是1.6％,表明所提出的控制方法有效地消除了音圈电机复杂迟滞的影响,提高了音圈电机的控制定位精度.     

音圈电机在电子式供氧抗荷调节器中应用研究

传统的氧气调节器均为机械式,其体积较大,响应速度慢,调节精度低.针对某新型机自主研制出一套电子式供氧抗荷调节器装置,介绍了其系统组成和工作原理,并针对音圈电机的工作原理设计出一套分段步进算法,根据呼吸腔与目标腔压差大小、正负及斜率等控制音圈电机动作,进而调节呼吸腔压力大小,使吸入氧气与灌入氧气平衡,并将此算法应用于抗荷测试试验.结果表明,采用分段步进的控制算法可以对音圈电机进行精确控制,在呼吸气阻力方面满足技术指标,调节精度高,响应速度快,达到了新一代战斗机供氧子系统的设计要求.     

直线电机轨迹跟踪系统快速终端滑模控制

为提高永磁同步直线电机伺服系统的控制精度和鲁棒性,满足高速度高精度运动控制系统的要求,提出了一种快速终端滑模控制方法并建立了电机系统数学模型.分析和证明该控制算法的稳定性和鲁棒性.与传统的滑模控制方法相比,该算法确保了系统状态在平衡点邻域内具有更快的收敛速度,并最终收敛至平衡点.通过选择控制算法中合适的参数值,系统可达...     

Realization of an adaptive voltage driver for voice coil motor

In this paper we describe a head servo-positioning system for hard disk drives (HDDs), in which the usual current command for the voice coil motor has been replaced by a simpler voltage command. This solution has proven advantages in terms of cost, since the voltage driver does not require any resistive shunt for current measurement and phase-shaping passive networks for the current controller. Also, it requires a lower pin count and can be easily implemented with a PWM power stage. The voltage driver consists of a voltage-controlled power stage, with a pre-filter placed at its input, plus a back e.m.f. feed-forward compensator. The role of the pre-filter is to provide a transfer function between input signal and VCM current as close as possible to that of a standard current loop, so providing a one-to-one replacement to standard current drivers. To achieve this, it can be shown that the filter must cancel out the low-frequency pole of the VCM, located in a position which depends on the electrical impedance of the VCM itself. This, however, may change by ±30% during HDD operations, due to self-heating and consequent variation of the VCM resistance. Such variation may lead to an unsatisfactory performance of the voltage driver, so an adaptation mechanism, capable of tracking variations of VCM coil resistance, must be set up. This paper presents an on-line estimation procedure, based on an extended Kalman filter (EKF), capable of estimating the VCM coil resistance with a high degree of accuracy. EKF, however, usually brings a high computational load, making it unsuitable for real-time, low-cost embedded applications. The paper presents two reduced-order model of the VCM, for which the EKF can be implemented with 30 and 50% less computational effort, respectively, while maintaining a good estimate of the VCM coil resistance. The paper reports experimental results of VCM resistance estimation, obtained with the proposed algorithm, running in 30 μS on a 25 MHz, fixed-point DSP. Also, the on-line estimation is used to adapt the pre-filter. Experimental results show that the servo performance with adaptive voltage driver is not affected by resistance variation and equivalent to that of the standard current driver.     

Perturbation wavelet neural sliding mode position control for a voice coil motor driver

To cope with the nonlinear electro-magneto-mechanical characteristics, this paper proposes a perturbation wavelet neural sliding mode position control (PWSPC) system for a voice coil motor (VCM) driver. A perturbed wavelet neural network (PWNN) approximator is used to online approximate the unknown nonlinear term in the VCM system dynamics. The PWNN approximator uses perturbed wavelet functions to handle the rules uncertainties like interval type-2 fuzzy sets. The structure learning ability enables the PWNN approximator to evolve its structure online. Further, the parameter learning laws and stability analysis are derived in the sense of Lyapunov function; thus, the parameter convergence and system stability can be guaranteed. Finally, the experimental results verify that the proposed PWSPC system can achieve favorable control performance such as good disturbance rejection and good tracking accuracy.

     

二维微载荷传感器的设计与分析

设计了一种二维微载荷传感器。用于仿生粘性材料的力学性能测试,也可用于一般的摩擦试验。利用应力集中原则对平行梁弹性体局部削弱,结合材料力学理论和有限元软件ANSYS对弹性体进行仿真设计。利用ANSYS后处理器中提供的路径映射技术,在弹性体应变最大的区域,确定弹性体应变计的最佳贴片位置。对传感器进行静态标定,得出其静态性能指标,其垂直方向的最大量程为3.0 N,分辨力为0.008 N;水平方向的最大量程为3.5 N,分辨力为0.01 N。     

基于STM32的微型步进电机驱动控制器设计

设计了一种微型步进电机驱动控制器,通过上位机界面修改步进电机转速、旋转角度、细分系数。该设计以STM32F103T8U6作为主控制器,以A4988步进电机驱动设备,上位机串口界面作为人机接口界面,详细分析步进电机驱动设备的工作原理、各部分接口电路以及控制器设计方案。通过实物设计实现了步进电机转速、正反转任意角度和细分系数的控制,并通过精确计算步进脉冲个数实现了任意旋转角度的精确控制,该驱动控制器步进角度精度高达0.112 5度。     

Design and analysis of MEMS based piezoelectric micro pump integrated with micro needle

Microsystem Technologies - This paper presents the design and simulation of piezoelectric micro pump integrated with micro needle. The proposed micro pump adopted rectangular piezoelectric vibrator...     

On-line constructive fuzzy sliding-mode control for voice coil motors

In this paper, a voice coil motor (VCM) featuring fast dynamic performance and high position repeatability is developed. To achieve robust VCM control performance under different operating conditions, an on-line constructive fuzzy sliding-mode control (OCFSC) system, which comprises of a main controller and an exponential compensator, is proposed. In the main controller, a fuzzy observer is used to on-line approximate the unknown nonlinear term in the system dynamics with on-line structure learning and parameter learning using a gradient descent algorithm. According to the structure learning mechanism, the fuzzy observer can either increase or decrease the number of fuzzy rules based on tracking performance. The exponential compensator is applied to ensure the system stability with a nonlinear exponential reaching law. Thus, the chattering signal can be alleviated and the convergence of tracking error can be speed up. Finally, the experimental results show that not only the OCFSC system can achieve good position tracking accuracy but also the structure learning ability enables the fuzzy observer to evolve its structure on-line.     

谐振式微加速度计设计与加工误差分析

为提高谐振式微加速度计的灵敏度和精确度,设计了放大惯性力的柔性微杠杆机构,从理论上分析了微杠杆机构的不对称误差,设计了误差消除机构;经有限元仿真分析证明:所设计的机构能有效减小由不对称误差产生的横向力,有效地消除了放大机构不对称误差对谐振器的影响。分析了形状加工误差对加速度计性能的影响,为制作高灵敏度和高精确度加速度计提供了保障。     

Voltage driven hard disk drive with voice coil model-based control

In this paper, we describe a new solution for driving the voice coil motor (VCM) in hard disk drives (HDDs), in which the usual current driver for the voice coil motor has been replaced by a voltage driver. When used in conjunction with PWM power stages, this solution becomes fully digital and has proven advantages in terms of cost, power dissipation and silicon area. To achieve the same performance of the current driver, the voltage driver requires a pre-filter placed at its input, to cancel out the electrical pole of the VCM. In the paper, we describe the voice coil model-based control (VCMC), a solution for implementing the pre-filter, which replicates the behavior of a current loop by using a model of the voice coil motor and its driver, including the saturation of the power stage. It is worth noticing that VCM resistance may change by 30% during HDD operations, increasing when the disk is performing repetitive seeks or decreasing when the disk cools down during track following. Such variation may lead to an unsatisfactory performance of the VCMC, so an adaptation mechanism, capable of tracking variations of VCM coil resistance, must be set up. This paper presents a pair of on-line estimation procedure, used to get the value of the VCM coil resistance during seek and track following, respectively. The first one is based on a standard LMS approach, aimed at identifying a simplified model of the plant with the least computational effort. The second exploits the presence of repetitive disturbances (RROs) to detect variations of plant gain and, in turn, of VCM resistance. It will be shown that both procedures are quite accurate in estimating variations of VCM resistance and their output can be used to perform on-line tuning of the VCMC. Experimental results show that the servo performance with the adaptive VCMC is not affected by resistance variation and equivalent to that of the standard current driver.     

多通道生物压电传感芯片微分析系统设计

为了满足石英传感阵列信号采集的要求,设计了一种基于虚拟仪器技术的多通道生物压电传感芯片微分析系统。该系统硬件部分由信号处理电路、数据采集卡和计算机等组成;软件部分采用图形化编程语言LabVIEW设计。利用该系统分析溶液电导率与石英传感芯片谐振频率偏移的关系。实验结果表明:该系统能够实现对频率信号的实时测量,并能实现数据的自动采集、处理、保存;可进一步用于生物大分子的检测。