Research Of Testing Method Of System Characteristics Based On Force Generator

In the process of force measurement, people not only obtain the force’s correct measuring result, but also require to estimate the trend of the measuring result. Only the modeling measurement can solve the complex dynamic measurement problems. On the basis of the force measurement system and the output signal, the key part of getting the accurate input force signal is to identify the transmission characteristics of the system. So the test of the force detection system’s system characteristics is one of the most frequently encountered problems. In the production of these devices, it is needed to give a stable force signal to the instrument’s force sensor and the whole machine to ensure the test of system characteristics.In order to complete the test of the force detection system dynamic characteristics, the project applies the systems’ excitation signal and the output signal to obtain the detection system’s dynamic characteristics. The specific processing method is: firstly, we get the excitation signal and output signal, the use Fourier transform the process this two signal, at last we use the quotient of the excitation signal and an output signal’s amplitude, and the difference between the excitation signal and the output signal’s phase in frequency domain to get the system frequency characteristics. In order to verify the rationality of the system test and analysis methods, the project applies electrical network model to simulate the force detection system’s dynamic characteristics(system characteristic simulation model). The project uses MATLAB and Autism Designer 2009 this two software to simulate and analysis the system characteristic simulation model’s dynamic characteristics. The project uses the simulation model’s excitation signal and output signal processed by Fourier transform to obtain the actual frequency characteristics of the simulation model. The actual frequency characteristics of the simulation model are compared with the theoretical frequency characteristics, and it is proved that dynamic characteristics’ test method and analysis method of the force detection system is feasible. Then this project actually builds a detection system, and a force generator based on leverage. The project uses the periodic triangular wave and periodic trapezoidal wave generated by the force generator as the detection system’s excitation signal. Then the project processes the force detection system’s excitation signal and the output signal by Fourier transform, then it get the force detection system’s frequency characteristics. This test verifies the feasibility of the system testing and analysis methods.The main contents of this project are: Firstly, in order to meet the system characteristics testing requirements of the force detection system, this project builds a force generator device based on the lever principle, which can generate different wave forces. Secondly, the project built the single chip microcomputer data processing and control unit to measure the output of the force sensor, complete the A/D conversion and realize data collecting and sending. Thirdly, the project uses MATLAB and Autism Designer 2009 to simulate and analysis the system characteristic simulation model of the force detection system. Fourthly, the error of the simulation analysis is analyzed, and the simulation error is reduced by choosing the appropriate sampling rate. Fifthly, this project completes the data transmission between the single chip microcomputer data processing and control unit and the test data processing platform. Sixthly, the test data processing platform is edited by MATLAB to complete the data processing, curve drawing, date saving and so on. lastly, the project tests the force detection system’s dynamic characteristics built actually, processes the measured data to obtain the actual system characteristics.