橡胶支座试验机测控系统的研究与开发

【作者】 黄灯；

【导师】 桂卫华；

【作者基本信息】 中南大学 ， 控制科学与工程， 2008， 硕士

【摘要】 橡胶支座是现代公路桥梁建设的常用构件,其力学性能直接影响公路桥梁工程质量以及使用寿命,因此公路桥梁橡胶支座的各项基本力学性能的检测是保证其质量的极其重要环节。目前,对橡胶支座的力学性能的检测主要是通过试验机进行压剪试验,模拟橡胶支座的真实受力情形而完成的,而橡胶支座试验机测控系统是实现对其力学性能检测的关键设备。介绍了材料试验机测控系统的发展概况和面临的问题,分析了橡胶支座试验机的系统结构和工作原理,提出了其测控系统的功能需求;在深入研究试验机工艺流程的基础上,设计了橡胶支座试验机测控系统的总体方案,采用TMS320LF2407,实现了测控系统的硬件电路,并详细介绍了关键部分的设计方法;阐述了测控系统的分模块软件开发,并介绍控制算法的实现。针对橡胶支座试验机电液伺服压力系统的非线性和参数时变性,提出用变论域模糊控制的方法来整定PID控制单元的PID参数以提高测控系统的压力控制精度;采用论域收缩方法、二元函数分片双一次插值技术,解决了一般PID参数自调整方法易陷入对某一工作点的局部优化的问题,保证了系统控制参数的全局最优性,并实现了试验机加载与保压的高精度控制。通过现场试验,比较了常规模糊PID控制与变论域插值模糊PID控制的效果。试验结果表明,文中设计的橡胶支座测控系统能保证系统的全局稳定性以及控制精度,能有效的克服因液压油的温度及粘度变化等因素导致的颤振现象和加载乏力的现象,并有效的将系统的压力加载超调控制在了3.5%以内。更多还原

【Abstract】 Rubber bearings are usually used in modern bridge buildings. And the mechanical property has so much direct influence on the quality and service life span of highway bridge construction that it’s a great important to measure rubber bearings’ basic mechanical property. Presently, the measuring work is mainly carried out by pressure and shear testing with testing machine which can simulate rubber bearings on-site working situation, and the measure-control system is the key equipment that can realizes the measurement of mechanical property of rubber bearings.The general situation of development of material testing machine’s measure-control system and the problem it currently faced are introduced, while its system organization and operating principle are analyzed, meantime the function demand of the measure-control system is put forward. On the basis of profound study on the technological process of testing machine, an overall plan of measure-control system was designed, the hardware was completed with TMS320LF2407, and the key method was introduced. The modularized software of the measure-control system is represented, and the realization of control algorithm is introduced. Aimed at the non-linear and time-varied parameters of the electro-hydraulic pressure system of the load-shear test machine, an interpolation algorithm fuzzy-PID controller has been designed and developed on the basis of variable universe. Variable universe and double-linear interpolation Algorithm of rectangular binary function have been adopted to solve the problems incurred by the self-regulation of general PID parameters concerned with local optimization, which guarantees the overall optimization of the system controlling parameters and realizes the high-accuracy control of testing machine’s loading and pressure maintaining.Then compare the effects between general fuzzy-PID control and the interpolation algorithm fuzzy-PID control based on variable universe through on-the-spot experiments. The comparing results show that the interpolation algorithm fuzzy-PID control based on variable universe can do a better job in safeguarding the overall stability and control precision of the system, and effectively overcomes the steady state error and chatter phenomenon which caused by the change of oil’s temperature and viscosity, and successfully controlled the pressure loading overshoot of the testing machine less than 3.5%.更多还原