Chi He

Design of artillery electrical performance parameters measurement and control system based on dual-bus

Main usage of artillery electrical system and its requirements on measurement and control system in design approval test are illustrated. Composition and working principle of measurement and control system for electrical performance parameters of gun based on Ethernet and GPIB are introduced. Design of hardware and software for measurement and control system is studied with emphasis. Technical difficulties as generality of control equipments and security of firing test existed in type approval test for artillery electrical system are solved. Operating interface for man-machine interaction is designed in software program. Practical application has shown that the system meet with the design indices.

Design of Firing Impulse Simulator and Analysis of Its Key Research and Development Technologies

A key technology problem with respect to approval testing is that of simulating firing impulse in large calibre weapon systems without firing live ammunition with many problems as high cost, strict environmental conditions, large numbers of staffing, wide test field, etc. There are two main methods in use at present: the first method is to carry out numerical simulation of gun firing dynamics with modelling and simulation (MS the second method is to conduct hardware-in-the-loop simulation test with firing impulse simulator (FIS). The latter types of methods generate impulse effect to simulate gun live firing from power sources of gunpowder, gas, or liquid. FIS with gunpowder or gas as power source take on problems as low control precision, complicated operating process, and poor safety. In this paper, a FIS which transfer test data via CAN (Control Area Net) bus was designed and developed. System composition and working principle are introduced based on analyzing features of similar products, where key technologies as counter-recoil analysis, mass and speed choice of pounding head, system safety design are studied with emphasis. The research results indicate that FIS can be used as an effective supplementary to live firing in approval test of weapon system.

Error Modeling and Simulation for Directional Testing of Space Block

A directional testing model of space block is studied for effective utilization of optical equipment as theodolite, which gives out the influencing range of testing error on the calculated results. Thus, gists for guaranteeing actual measuring accuracy and improving testing efficiency are provided. And, the open question in accurate measurement of space block direction can be solved. In this paper, angular information of two different marker points on space block are used for directional testing, through which a partial derivative based error propagation model is built. The rationality and credibility of this model is verified by Monte Carlo simulation. Besides, its calculation results are validated through conventional variance test method in the end. The validation results indicate the rationality and credibility of the partial derivative based error propagation model. The error propagation model can be used to study measuring error distributions on different areas of space block, which lays a firm foundation for optimizing measuring stations distribution, and guarantees measure precision.

Optimal sample size allocation for integrated test scheme

Integrated test scheme (ITS) make comprehensive use of simulation and field test to evaluate system performance, which takes on merits of low cost, full-scale assessment, and high precision. Sample size determination (SSD) methods for ITS are analyzed, which reveals the problem and contradiction in classical method and Bayesian method using standard power prior for design. Design effect of experiment is proposed considering the influence of prior sample size, which is used for elicitation of modified power prior for SSD of ITS. Taking average posterior variance for parameter of interest as the output precision, optimization equation for SSD of ITS under required posterior precision constraint is designed, whose effectiveness is illustrated with a utilization example.

Application of VI technology in DSO measurement system with GPIB interface

Digital storage oscilloscope (DSO) is, with applied far going, high sampling frequency and measuring accuracy, a common testing instrument in signal acquisition and processing. While many DSOs are used together to measure multi-channels of signals, there exist some problems in synchronous comparing, acquisition, storage and plots of different signals. In order to solve these problems, the features of three LeCroy DSOs with GPIB interface were analyzed and a DSOs measurement system was constructed by Virtual instrument (VI) technology. Software design and user interface of the measurement system were discussed with emphasis. The system had been used in test of some position servo system, whose results indicated that the software took on rational design concept and flexible operation. Beside, measuring accuracy and reliability of the system satisfied the requirements of design technical specifications.

A novel sea wave simulation test environment construct for shipborne weapons systems

A key technology problem with respect to approval testing and evaluation is that of simulating sea wave impact in shipborne weapons systems, both in terms of land-based and sea-based tests. There are two main methods in use at present: the first method is to build large-scale water pool, in which the shipborne weapons system under test is mounted to a special model ship; the second method is to simulate sea wave impact via a six degree of freedom motion simulation platform. Because of their extremely high costs and engineering implementation difficulties, the two methods have not generally been used in practice. In this paper, a flight path and sea wave impact simulation system which transfer test data via CAN bus was designed and developed, and five mathematical models of typical flight paths (such as a horizontal line path) and three levels of sea wave impact models were established. The sea wave impact models were superimposed to flight path models via equivalent theory and coordinate mappings; and realistic fighter flights path and sea wave impact environments were, in shipborne weapons system land-based tests, constructed via an input simulation in which the mixed signal is input to the control loop of weapon system under test. The models and methods in this paper were used in a battery of naval gun approval tests, and the tracking performances of the shipborne weapons systems were simulated via MatLab. The simulation test results indicate that the new simulation method and system can meet the requirements of shipborne weapons Operational Test and Evaluation (OT&E) protocols completely.

A Novel Testing Approach for AM Tracking Error of GCS DEWE2010 Based

The functions and approval test requirements of the GCS were introduced. The composition and working principle of DEWE 2010, a portable data acquisition system, were presented, which provides a feasible technological approach for software demodulation of AM signals in GCS testing. On researching the principles of AM signal modulation, two novel coherent and non-coherent software demodulation methods for AM tracking error of GCS were devised with mixed programming of LabWindows and MatLab. Test and simulation results show that the measuring accuracy and automation level of novel AM tracking error testing approach meet the requirements of test measurement.

Design of Test and Adjustment System for Coordinator of Infrared Seeker

Test and adjustment system of coordinator (T&ASC) is, virtual instrument technology based, developed. PXI measurement control platform, turntable system, target simulator and air source equipment are integrated in hardware design. Multithreading, IMAQ Vision module and DLL techniques are used in software programming. Technical difficulties as synchronous receiving of RS422 data with high speed, direct display of LVDS video image and integrated control of turntable are solved. The system achieves the integrated design of test, control and adjustment function, which can carry out overall performance tests for coordinator automatically, and execute system parameters calibrating and adjusting intelligently.

Study on Identification Method of Rapidity Performance Parameters DEWE 2010 Based

Functions and features of servo system are, as well as composition and working principle of DEWE 2010 portable data acquisition system, introduced. Feasibility of using DEWE 2010 data acquisition platform to test rapidity performance parameters of servo system is analyzed. Identification method for rapidity performance parameters is given out by research of rapidity model and signal definitions. Parameters are, such as overshooting, fluctuation number and transferring time, defined for servo system. LabWindows and MATLAB co-programming method is used to realize automatic measurement of rapidity performance parameters. Test results indicate that the measuring accuracy and automation level of this method meet the test requirements.

Design of hydraulic power subsystem in shock simulation system for shipborne weapons

The category of shipborne weapons as well as the importance and effect of naval gun mounting servo system are described. The status and difficulty in type approval test of naval gun mounting servo system are introduced. A shock simulation testing system for shipborne weapons based on electrohydraulic servomotor is put forward, which can simulate all levels of ocean wave shocks, inertia moment and shooting shocks. Performance of hydraulic power is analyzed according to power requirement of simulation system, mechanical structure of subsystem is confirmed, and diameter calculation for hydraulic oil supply pipe as well as type selection for power accumulator are accomplished. Experiment result shows that this simulation system meets with the technical design requirements.