Design And Implementation Of Multifunctional Comprehensive Test Equipment

Flight controller is the core device in space flight test.It is used to control and monitor the operation state of aircraft in order to obtain the performance parameters of aircraft.The reliability of the controller is directly related to the success or failure of flight test.In order to realize the function test of a flight controller,aiming at the problems of single interface,limited function and low comprehensiveness of conventional test equipment,a multifunctional comprehensive test equipment based on PXI architecture is studied and designed,which can simulate the working environment and test the performance of the controller,and realize the functions of multi-channel automatic switching control,multi-mode digital communication,analog acquisition and monitoring and system self-test.This paper expounds the background and research significance of the subject.By analyzing the development status and trend of automatic test technology,combined with the actual working situation of flight controller,the general scheme of the system is designed according to the principles of generalization and standardization.This paper focuses on the hardware circuit design idea of each functional module of the test equipment,analyzes the FPGA logic implementation process,supplemented by safety and reliability design.The design contents of comprehensive test equipment are as follows:With FPGA as the main control chip,the communication between the upper computer operating system and the device board is realized through PXI architecture;Combined with the constant current source,the switching control module is designed,which can stably output the control signal,and realize the multi-channel automatic switching control of the tested equipment according to the received configuration data;Using RS-422 communication technology,the interface circuit of digital quantity communication module is designed,and the demodulation multi-mode communication function with UART,HDLC and PCM is realized through the interface;The analog acquisition circuit is designed by using Hall current sensor and linear optocoupler to complete the real-time isolation acquisition and monitoring of the current and voltage input and output of the controller,and the acquisition results are uploaded by FPGA;The module self-test function is designed,and each module can test the effectiveness of its own function before testing.After the design of the comprehensive test equipment is completed,the function of each functional board is tested combined with the host computer software,and the temperature cycle test of the whole machine is carried out under the condition of power on.The results show that all indexes of the equipment meet the expected value,have high reliability and practical engineering value.