为快速建立数控机床工作台运动监测系统,缩短开发周期,使用西门子S7-1214 PLC的高速计数器对编码器计数,并通过PROFINET接口将计数值发送给上位机;上位机在VC++开发环境中采用Winsock控件实现与PLC间的的TCP通信,获取各编码器的计数值,并换算成数控机床X、Y轴丝杠的位移,从而拟合其实际运动轨迹,通过实际运动轨迹与理想运动轨迹的比较即可实现机床运动的在线监测。
In terms of the mechanism design of network topology and weight dynamical evolution, the traditional evo- lution model of complex network doesn' t take into account the network flow' driving function to evolution of trans- portation network. This paper introduces the dynamic system of network flow and analyzes the role played by three factors in the process of evolution of transportation network which are scale growth of network flow, constraints of spatial distance and flow distribution mechanism based on shortest path. It finds that these three factors can' t change the connectivity power -law behavior; flow distribution mechanism based on shortest path is the important factor to ef- fect network flow maldistribution and the spatial distance plays a key role to effect the network assortative mixing.