Research On The Control Technology Of The Fully Automatic Lever Type Force Standard Machine

Lever-amplification force standard machine is the high grade in force measurement and force transfer of a nation. With the implementation and verification regulation of weighing sensor OIML R60 international proposal and industrialization progress, put forward higher requirements on the loading efficiency and accuracy. In recent years, with intense research to the lever-amplification force standard machine and advances in engineering, such as precise bearing, electric poise loading independently and self-balancing technologies applying to the dead weight force standard machine. It is necessary to research the new skill in the lever--amplification force standard machine.Based on 500 kN new lever-amplification force standard machine, my subject mainly made a new attempt about hardware and software of automation control affiliating with new lever-amplification force standard machine. In this way, it proves the performance of the equipment further. Under the premise of ensuring the accuracy, improve the work efficiency of the equipment and the full automation of the verification process, so the performance of the equipment has been further improved.First of all, according to the new performance requirement of force standard machine, the machine construction of 500 kN new lever-amplification force standard machine is designed, mainly including weight parts, weight drive components, hanging component, lever structure, Work Part etc. The critical components- lever which influences the precision and reliability of equipment carry out FEM analysis using ANSYS to ensure mechanical structure parts conform to the design requires.Secondly, according to the requirements of the structure and target of the 500 kN lever type force standard machine, based on the theory of closed loop control system, put forward the control system model for the equipment, drawing control principle diagram. Then according to the performance requirements of the servo control system of the moving beam, a suitable model of the servo control system is established, and the optimal amplification ratio of servo motor position control is determined on the basis of the parameters of the system. According to the requirements of 9030 card, select the reasonable form of communication, Solve the control unit, data communication problems between the motor control card, I/O card and computer.Again, according to the performance requirements of new force standard machine and comparing the advantages and disadvantages of the commonly used control types in the field of industrial control, the control scheme of the new 500 KN lever type force standard machine is determined, then carry on the research from two aspects of software and hardware.In terms of hardware, according to the control mode to draw electrical principle diagram of each unit, good selection of key electrical components; then the design of the control unit, including data acquisition and processing unit, emergency system, anti-interference design etc. The I/O control card and motion control card are used to solve the problem that the control switch and the servo control is more complex, this will make the control way is more simple.The software aspect, the first analysis determine the function modules of the software according to the hardware system, design the basic framework of interface and program; then detailed design the weight automatic/manual selection module, lever monitoring module, motor of moving beam drive module, experiment module and data processing module, finally completed the design of control software of the new type force standard machine. achieve the full automation of equipment condition monitoring, real-time animation display and verificationFinally, to test the performance of the complete machine, according to the relevant verification regulations, begin to load characteristic test and creep test of the sensor, the creep characteristics, the repeatability, nonlinear and other related indicators, determine whether the new type force standard machine meets the design requirements.Through preliminary experiments, the new 500 kN lever type force standard machine to meet the performance design. That using the method of servo control technology, motion control card, I/O card and microcomputer to achieve accurate control of large equipment is feasible, the control method is simple, reliable, high control precision, Software can monitor the status of equipment in real time and show the animation display, achieve a new type of 500 KN lever force standard machine automatic control greatly improves the degree of automation equipment.