| The Norm Force Machine(NFM) is the high grade in force measurement and force transfer of a nation. It's one type of force standard machine which can be used to validate the capability of load cell. Because the NFM is the high grade of kinds of standard force machine, its capability will restrict the nicety of all force measure vocation. Its good capability is very important to the economy, military affairs, space flight etc. of a nation.There are several type of force standard machine, for example, Dead Weight Force Standard Machine(DWM),Lever Standard Force Machine(LM), Hydraulic Standard Force Machine(HM),Build_up Standard Force Machine. DWM is the most precise force machine. The main structure of DWM is the mechanical segment. But the working of DWM is depending on the electrical components.The designing of mechanical structure and the precision of poise decide the precision of the DWM. The working of DWM force machine needs good control system and its precision of measurement depends on it, too.We actualized the job aim at these measurement and control problems.i. Establishing and analyzing the mechanics model and the control model of 1MN force machine Through the analysis of the mechanics model and kinematics model, we know the precision of the 1MN is mainly decided by the precision of the poise. And we know that the realization of the p precision of DFM depends on the good quality of its control system. Among the working process of the DFM, there are several working processes are difficulties of its operation, the "exchange poise course" of loading course is one of them. The adoption of different control arithmetic solved the non-linear, big-lag of the 1MN force machine. The new-designed controller of the control system accomplishes the controlling of the main working of the system and detecting the many signals of the system including analog and digital signals, the controller also takes quick and general protection to the equipment during working. Through many times experimentation we confirm the many tache of the equipment can accord the requirement of working. The controlling realizes the automation of working and signal processing. The method used in this equipment to realize poise exchange can apply to the similar equipment.ii Designed and developed the embedded controller of the control system of 1MN force machineWe designed a DCS control system for the control system at the basis of the establishing and analysis of the system module. The upper controller of the system is industrial computer. The bottom machine is PLC that fits logic control and embedded controller that has the 51-chip as the core control unit. The embedded controller realized the controlling of the main working and the collection of the many signals, its capability decides the capability of the equipment.The control core of the embedded controller is 51 serial single-chip. The embedded controller has 3 D/A converter to control the working of the beam device (ESV),preloading device(VSE), mobile shackle(GKA).The controller also can control the correction device to follow the suspension device with the feedback signal. This controller can read the signal of displacement of the foregoing devices to estimate status of working and realizes the controlling for them. After long time working, the controller shows great quality, so it can apply to the requirement of the equipment. iii Selecting adaptive control arithmetic for the exchanging of poise course1MN has several functions and each of them is established by several process. Several of them can be realized by simple control, some of them cannot be realize through simple control arithmetic because of the non-linear and big-lag of time, exchanging of poise course is one of them. So we studies several arithmetic to solve this problem.PID arithmetic has the most extensive apply in industrial controlling, the quick development of the computer technology and information technology make the application of Digital PID is more extensive. Th...
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