【作者】 许万；

【导师】 陈幼平； 谢经明；

【作者基本信息】 华中科技大学 ， 机械电子工程， 2009， 博士

【摘要】 在现代机械制造中，多轴运动控制的应用已经越来越普遍，用电子方式来实现机械运动轴之间协调同步，取代了传统的机械凸轮和齿轮，给机械设计制造带来了巨大的灵活性。为了有效协调、同步各个轴的运动过程，实现高精度的多轴运动控制，一个实时高效的数字通信网络是必不可少的。以太网具备高带宽、低成本、开放性好、技术成熟等特点，这些特点都非常适用于高速、高精度多轴运动控制系统，但由于标准以太网也存在着很多问题，本文针对将以太网应用于多轴运动控制系统作了较深入的研究，主要涉及到以太网实时调度、时钟同步、多轴控制算法等问题。本文首先分析了标准以太网接口在运动控制系统中应用存在的问题，在不改变以太网介质层接入机制的前提下，建立了一个实时以太网模型，提出了一种基于动态时隙的以太网实时调度方法，并提出了一种应用于该调度方法的容错机制。网络的时延对实现预测控制算法非常重要。本文研究了基于TDMA的通信系统中报文延迟问题，建立了时延模型，讨论了报文溢出概率，给出了报文驻留时间的概率分布和期望值的计算方法，并说明了如何选择系统参数以满足系统的实时性要求。为了能在异步控制网络上实现采样同步，可采用时钟同步方法。本文分析了几种主要的以太网时钟同步协议，通过比较，可以看到基于IEEE1588的时钟同步方法最适用于工业控制网络，本文还针对边界时钟在线性级联拓扑结构中存在的问题，提出了一种改进方法。本文讨论了基于实时以太网的多轴运动系统基本结构，然后建立了基于实时以太网的多轴运动控制系统数学模型，分析了采样周期，采样方式，以及节点驱动方式对控制系统性能的影响。分析了几种基于交叉耦合的同步控制策略，主从式同步和平衡式同步。通过实验，比较了采用不同同步策略时，各轴跟踪性能和同步性能的差别；提出了一种基于交叉耦合的广义预测控制算法。最后，基于前面的工作，进行了基于实时以太网的凹版印刷机套准系统的设计。更多还原

【Abstract】 Multi-axis motion control system becomes more and more popular in modem manufacturing. Synchronization motion between machine axes can be achieved by electrical method instead of the mechanism, which makes manufacturing system more flexible. In order to synchronize all machine axes effectively and achieve high precise of motion, it is necessary to establish a real-time and high-effective digital communication network. With its high bandwidth, low cost, good opening, mature technique, the Ethernet is especially suitable for Multi-axis motion control system. But still there is a great deal of problems to be solved. This dissertation makes deep research on the application of Ethernet in the Multi-axis motion control system, which mainly concerns the Multi-axis motion control algorithm, clock synchronization, real-time scheme of Ethernet.Firstly the problem on the application of Ethernet in the Multi-axis motion control system is analysed in this dissertation. On the premise of using CSMA/CD, a real-time Ethernet model is built, and a real-time scheme method based dynamic time-slot allocation is proposed. A fault- tolerance mechanism in such scheme method is proposed.The delay of the control network is important for predictive control. Message delay in TDMA system is studied. A delay model is built. The message overflow probability is discussed. The probability distribution and the expectation of message sojourn time are presented. This paper illuminates how to choice system parameters to meet the real-time requirements of the system.Using the clock synchronization, synchronous sampling could be realized on an asynchronous control network. Several time synchronization protocols are analysed in this dissertation and proves that the clock synchronization method based IEEE 1588 is the most suitable for industry control network. An FPGA-based implementation of the IEEE1588 pprotocol was developed in this paper. Basing on the lack of boundary clock in the line topology, an improved method is proposed.The basic structure of the multi-axis motion control system based on real-time Ethenet is discussed in this dissertation. And then the model of a multi-axis motion control system based on real-time Ethenet is built. Analyses of sampling period, sampling method and the influences of the nodes driven modes on the system performance are made. Three synchronization control strategies are analysed in this dissertation. The experiments demonstrate the differences of the tracking and synchronization performance using different strategies are presented. A cross-coupling generalized predictive control algorithm is proposed.At last, based on the researches above, a register control system of rotogravure printing press based on real-time Ethernet is designed.p更多还原