Lissajous曲线拟合法评估编码器细分误差

为实现编码器细分误差的快速评估,提出了一种Lissajous曲线拟合法评估编码器细分误差的方法.采集编码器两路相位差为π/2的三角波光电信号,然后,对光电信号归一化处理后得到两路信号的Lissajous曲线,利用数值函数拟合实验得到Lissajous曲线,并进行拟合优度检验,最后,利用数值函数表计算编码器的细分误差.多次实验验证:该方法是简单可行的.     

光电轴角编码器细分误差的Matlab仿真评估方法

本文根据影响编码器光电信号的因素,利用实测的Lissaious图及Matlab超强的数据处理功能,提出利用Matlab仿真评估编码器细分误差的方法.针对编码器莫尔条纹原始信号的正弦性、正交性、等幅性及含直流电平这几种典型特征,利用Matlab仿真对产生误差的原因进行单项分析评估.     

基于STC单片机的增量式编码器解码电路设计

为了准确获得增量式编码器的转角位置,根据编码器两路信号输出的方波相差90°的特点,设计了增量式编码器的解码电路,将编码器的原始输出信号转变为计数和方向两组信号。采用STC单片机对处理后的信号进行了处理运算,实现了转角的准确显示,为其在二维转台控制中的应用提供了基础。     

电磁定位耦合信号提取方法研究

电磁定位系统中,正弦耦合信号提取是关键,其结果将直接影响定位精度.在多频正弦信号耦合系统中,由于电子元器件和系统误差等原因,会导致信号频率有偏差,而且可能存在饱和畸变,对参数提取造成了困难.基于最小二乘法原理和频率逼近思想,提出一种用于有频偏的多频率有饱和正弦信号幅值和相位的提取方法.该方法在有饱和畸变的正弦信号中提取未饱和的样本,通过最小二乘法拟合计算,估计信号参数,然后改变信号频率逐渐逼近最佳频率,使得误差平方和最小,从而提取准确参数.仿真分析了噪声、信号饱和程度和采样点数对参数提取的影响.最后通过实验验证了该方法的有效性和实用性.     

光电轴角编码器细分误差的Matlab仿真评估方法

本文根据影响编码器光电信号的因素,利用实测的Lissajous图及Matlab超强的数据处理功能,提出利用Matlab仿真评估编码器细分误差的方法。针对编码器莫尔条纹原始信号的正弦性、正交性、等幅性及含直流电平这几种典型特征,利用Matlab仿真对产生误差的原因进行单项分析评估。     

基于PID神经网络控制微信号发生装置

高压电网中电子式互感器输出信号一般为毫伏级模拟信号,在高压保护、测量装置研发试验中需要能够提供高精度微小信号的继电保护测试仪.文中介绍了一种基于PID神经元网络负反馈控制技术和FPGA控制高精度串行DA转换输出精准微小信号的系统设计方案,分析了装置为提供高稳定度小信号所采用的新方法,设计了基于现场可编程门阵列(FPGA)技术的16位并行数字信号串行输出控制模块.系统通过嵌入微控制器的正弦波形产生算法和自适应PID控制算法输出高拟合离散正弦波数字信号.由FPGA控制输出的各路离散信号经串口DA转换、滤波后输出的模拟电压信号稳定可靠、频带宽、动态特性良好.该测试仪输出的小信号电压变化比差测量值满足0.2级电子式互感器准确度的要求.     

基于ARM的振动传感器幅频特性测试系统研究

设计了以ARM微处理器为核心的中央控制处理单元,以完成振动传感器幅频特性测试的系统.利用ARM上集成的数字模拟转换电路(D/A)的输出通道1产生频率可调的等幅正弦信号,输出通道2对可变增益运放电路进行控制,使得振动传感器输出信号幅度在系统工作范围内,采用模拟数字转换电路(A/D)将振动传感器输出的信号整周期采样,对信号...     

基于合法信号认知的脉冲信号滤波技术研究

光电脉冲编码器输出脉冲信号到达滤波器的信号为合法信号与干扰信号的叠加,为了滤除干扰信号和得到合法信号,有基于合法信号认知并滤出合法信号以外的各种信号和基于干扰信号认知并滤出干扰信号两种滤波策略.由于脉冲信号的特征容易被认知,故对脉冲信号的滤波宜采用基于合法信号认知的滤波策略.本文以一实际永磁同步电动机的旋转脉冲编码器为例详细介绍了这种策略及其实现,并采用FPGA构成了滤波器进行实验研究.实验结果表明了方法的正确性.     

基于云计算的编码器信号误差补偿系统设计

传统的编码器信号误差补偿系统存在着补偿精度低的缺陷,为此提出基于云计算的编码器信号误差补偿系统。编码器信号误差补偿系统硬件设计包括编码器模拟控制单元、电源单元、信号采集单元与通信单元,软件设计包括通信模块、信号处理模块与信号误差补偿模块,通过编码器信号误差补偿系统硬件与软件的设计实现了编码器信号误差补偿系统的运行。通过实验得到,设计的编码器信号误差补偿系统补偿精度比传统系统高出30%,充分说明设计的编码器信号误差补偿系统具备极高的有效性。     

光电轴角编码器细分误差动态评估方法

介绍了一种光电轴角编码器细分误差动态评估的方法.光电轴角编码器匀速转动时,采集相位差为π/2的两路精码正弦光电信号,然后对采集到的光电信号进行等转角数据处理及谐波分析,从而求出光电信号波形参数,波形参数确定后可以建立波形方程.再将波形方程代入到细分误差的计算公式求出细分误差.试验结果表明,该方法是有效的.     

基于数字交流伺服控制芯片IRMCK201的应用

介绍了一种基于IRMCK201的高性能数字交流伺服运动控制芯片的应用,分析了交流伺服电机矢量控制的基本原理,芯片的内部功能模块及以IRMCK201为核心组建的交流伺服系统。通过此系统,可简单快速地确定永磁同步电机的转子初始位置。实验证明,利用IRMCK201运动控制芯片组成的全数字交流伺服系统,省去了用传统单片机或DSP必须编写大量复杂程序的麻烦,其应用灵活,能够获得十分良好的性能。它是新一代交流伺服控制系统的理想解决方案。     

Low-speed motion control of a mechanical system

Position control of a mechanical system at low speed in the presence of dry friction leads to a slip-stick process and steady-state errors when state feedback is used. In this article, the power transfer between servomotors and the system is analyzed using a Hamiltonian formulation. The analysis shows that power dissipation at low speed cannot be achieved efficiently using a proportional derivative error feedback, with constant gains. A sliding mode approach is proposed and evaluated for achieving accurate positioning of a servomotor in the presence of significant dry friction. Simulation results show the performance of a constant-gain sliding mode controller and of a self-adjusting sliding mode controller.     

Observer‐Based Adaptive Output Feedback Fault Tolerant Control for Nonlinear Hydro‐Turbine Governing System with State Delay

This paper focuses on the problem of adaptive output feedback fault tolerant control for a nonlinear hydro‐turbine governing system. A dynamic mathematical model of the system is established, which aims to investigate the dynamic performance of the model under servomotor delay and actuator faults. Then, a fault estimation adaptive observer is proposed to achieve online real‐time diagnosis of system faults. Based on the online fault estimation information, an observer‐based adaptive output feedback fault tolerant controller is designed. Furthermore, under reasonable assumptions, the results demonstrate that the closed‐loop control system can achieve global asymptotic stability by Lyapunov function. Finally, the numerical simulation results are presented to indicate the satisfaction control effectiveness of the proposed scheme.     

基于工业以太网的实时控制性能分析

以太网应用于工业网络控制系统是控制网络的发展方向，但它采用的CSMA/CD媒体访问机理，对于一些时间要求严格的控制过程会造成响应时间的不确定性。在工业网络中采用交换以太网可以消除传统共享以太网中存在的网络操作的不确定性，从而有效提高网络控制系统的控制性能。该文从理论上分析并计算工业以太网的最大通信延时，通过伺服二阶PID数字网络控制系统实例，定量分析网络协议和网络负载对网络控制性能参数的影响，为网络控制系统的设计提供了理论分析依据。     

Laboratory experiment of the structural sensing method using the accurate artificial vibrator

This paper presents a structural sensing method using the accurate artificial vibrator and shows the results of vibration experiments in laboratory scale. The accurate artificial vibrator generates harmonic forces by rotating an eccentric mass. Since the rotation is accurately controlled by means of a phase control type servomotor, the vibrator generates accurate harmonic forces periodically. The phase information obtained from the servomotor let us calculate the force function precisely. Applying Auto-Regressive eXogenous (ARX) model to the time series of force function and measured displacement responses yields the Green function of a target structure. In this research, we investigated the performance of prototype system and developed the Green function estimation method. We also conducted laboratory scale vibration tests in which the prototype system was applied to a two-meter simple beam. The estimated Green function was simulated by the analysis of Finite Element Method (FEM) and its structural model was successfully determined.     

经济型网络化数控系统的开发与应用

文中介绍了基于工业PC和专用DSP运动控制技术的经济型网络化开放式数控系统。在WINDOWS平台下,利用PC丰富成熟的资源和专用DSPMCX314AS强大的运动控制功能,并使用VisualC++和COM技术开发系统软件和API,最终形成多功能、低价格、高性能、简单、可靠、具有多轴多通道控制能力,丰富的标准接口,可配套使用多种伺服驱动单元和真彩色液晶显示器,连接以太网络通信、同CAD/CAM及管理系统互动的数控系统产品。该系统已成功应用于对立式铣床X8126的改造。     

Internal model control based PID tuning using first-order filter

The selection of filter plays an important role in internal model control (IMC) based controller design. As per the rule, for a minimum-phase delay free plant, IMC based controller is obtained by augmenting a filter. We suggest the use of first-order filter for controller design, which is then parameterized to a conventional PID controller. The proposed scheme brings filter size reduction, closed-loop bandwidth enhancement, and easy formulation of the PID structure. The proposed scheme is applied to some class of linear and nonlinear processes. Further the hardware testing for velocity control of precision modular servo system which contains DC servomotor is carried out through this scheme. Quantitative comparison of servo, regulatory and optimal attributes of the proposed scheme with other popular IMC-PID control techniques depicts sharp reference tracking, good disturbance rejection and minimum integral error performance.     

Inverse dynamics based robust control method for position commanded servo actuators in robot manipulators

In this paper, a simple torque to position conversion method is proposed for position commanded servo actuators used in robot manipulators. The torque to position conversion is based on the low level controller of the servomotor. The proposed conversion law is combined with a backstepping sliding mode control method to realize a robust dynamic controller. The proposed torque based method can control a servomotor which can otherwise be operated only through position inputs. This method facilitates dynamic control for position controlled servomotors and it can be extended to position commanded robotic manipulators also. Simulation and experimental studies are conducted to validate the proposed torque to position conversion based robust control method.     

Non-circular cutting with a lathe using a three-stage intelligent controller

In this paper, a three-stage intelligent controller (TSIC) for non-circular cutting with a lathe (NCL) is developed. In the first stage, an effective neural network is used to learn the dynamics of the voice coil servomotor system. Then a modified zero-phase tracking control (MZPTC) based on the learned model is designed to obtain an acceptable tracking result. Because MZPTC is a type of feedforward control, its performance cannot be ensured as the system is subjected to external load or the aging of system components. In the second stage, an adaptation in control input generated by a fuzzy sliding-mode control is then synthesized with the previous MZPTC to ameliorate control performance. The third stage is to use a forecast compensate control to compensate the cutting error caused by the variant cutting depth (or cutting force). The experimental results of NCL using TSIC, including tracking accuracy (i.e. profile error of finished workpiece) and smoothness of control input (i.e. surface roughness of finished workpiece), are much improved.     

基于PIC单片机的肉丸机控制系统设计

介绍一种肉丸机的控制系统,以PIC单片机作为核心控制器,包括信号检测模块、按键控制、PWM输出等部分。该系统通过按键选择,可以工作在几种模式下。肉丸机由伺服电机带动,通过对PIC单片机产生PWM波的精确控制,来控制伺服电机准确的移动与定位,将制作好的肉丸有序整齐地放置到专用的托盘上。该系统属于PIC单片机应用系统,具有广泛的适用性。