The Research Of An On-Spot Calibrator For The Data Acquisition Technology In The Shooting Range

The Seventh Institute of China Aerospace Science and Technology Corporation has undertaken the R&D and production of tactical weapon systems and military trade projects.At their different stages,it is necessary to conduct the flight tests in the shooting range and collect the high precision range data on site by using the range data acquisition system to verify and improve the design.The tests in the shooting range are characterized by complexity and variety in test items,harsh environments(including temperature,humidity and electromagnetic condition in the test venue)and high test costs.Therefore,it is important to ensure the accuracy of the acquisition equipment in the shooting range.Generally,only after the data acquisition equipment is calibrated in the laboratory,can it arrive at the shooting range after a long-distance transportation.It's working conditions are considerably different from the calibration conditions in the laboratory.Harsh environmental conditions(high temperature,low temperature,high humidity,smog,dust,vibration,etc.)and frequent testing bring severe challenges to the reliability and accuracy of data acquisition equipment.There are two problems in onsite calibration of data acquisition equipment in the shooting range:(1)As there are too many test items,the involved measuring standard instruments are in great varieties and in large quantities;In this case,the calibration operation is complicated;(2)As the measuring standard instruments are mostly valuable precision instruments,harsh environment in the shooting range is difficult to meet their environmental requirements in use.Therefore,it is necessary to develop an on-spot calibrator for the data acquisition equipment in the shooting range.In this thesis,based on the JJF 1048-1995 Data Acquisition System Calibration Specification,the working principle,working environment,tested items and sensor output signal characteristics of data acquisition system in the shooting range are analyzed.The high precision programmable arbitrary signal generator is developed to output the signal;on this basis,the standard information base for the sensor is established,which can simulate real output characteristics of the sensor in the flight test environment,facilitating retrieving the relevant information in the calibration process at any time and outputting it through the waveform generator.According to the actual demands of data acquisition system for calibration,the communication module isdeveloped to be compatible with different instrument communication interfaces.The communication interface collects and exchanges the data through the PXI bus to realize automatic data collection based on calibrated system.The on-spot calibrator for the data acquisition equipment in the shooting range can fully meet the requirements of on-site calibration,which is characterized by multiple calibration parameters,small volume,light weight,ease to carry and convenient on-site operation.As the calibrator can be used to test the data acquisition equipment in the shooting range on site,it makes the test result more realistic and reliable,providing powerful measurement guarantee for the development of aerospace products.In addition,it can also be used as a standard signal output device to provide measurement and detection services for the same type of signal acquisition equipment;specifically,it can be directly applied to experimental spot to verify the calibration and function of data acquisition equipment on spot.