Development Of 200N Force Standard Machine

There are urgent needs of the force standard machine with reasonable mechanical design,stable structure,advanced electrical equipment,accurate and reliable control system in small force metrology field.The 200 N force standard machine developed in this thesis ensures the unity and reliability of national measurement unit system.It is beneficial to the production,trading activities and development of science and technology in small force metrology in China.The 200 N force standard machine has been developed in this thesis.The force can be generated directly by applying the dead weight.The force standard machine contains weights loading and unloading components,weighs stacks and corresponding holders.The original design has are 8 stacks of weights in the 200 N force standard machine,realizing the non-retrogression loading process of force with broad range of load.Based on the Programmable Logic Controller(PLC),the control system was established according to the analysis of the controlling requirements of the force standard machine,including several modules.The PLC,sends the data to a servo amplifier through the motion control module,controls the servo motor driving the work platform in order to obtain weight carrier smooth movement and accurate positioning.The weight stacks can be selected and loaded automatically according to different load range.Instead of traditional operating platform,the online operation with interface design on Portable Android Device or smart phone through Wireless Fidelity connection has been introduced to the force standard machine,so as to obtain a more convenient and safer human machine interface.In this thesis,the hardware composed in 200 N force standard machine and the interface and communication method among hardware are studied in detail.The frame and the function of controlling module in the software of measurement are studied comprehensively.Finally,this thesis completes the performance verification of the 200 N force standard machine,and the evaluation of the uncertainty of the whole machine.It shows that the 200 N force standard machine fulfill the international advanced level.