Research On The Integrated Measuring Technique Of The Mass Properties For Missile And Rocket Model

The quality characteristic parameters mainly include mass,center of mass,moment of inertia,and inertial product.These parameters are basic intrinsic parameters that describe the mechanical properties of moving objects and play a crucial role in aerospace,construction machinery,weapon systems,and other industries.For high-speed objects such as aircrafts,satellites,and missiles,the accuracy of the quality characteristic parameters directly affects the quality of the attitude control of the flight and the hit rate of the weapon.Therefore,it must be measured accurately.However,these products have relatively large long diameters and are difficult to turn over or upside down.Therefore,it is difficult to test,and measurement accuracy of the center of mass in the high direction is difficult to guarantee;moreover,there are many mounting times and the safety and test efficiency are low in the moment of inertia test.problem.For this reason,this paper develops an integrated test system that can realize the measurement of mass,centroid,eccentricity,moment of inertia and inertial product of the object to be measured in a single setup.First,on the basis of summarizing the measurement methods of quality parameters at home and abroad,the existing quality characteristic parameter measurement equipments are divided into two categories of dynamic and static separation structures and integrated structures according to structural characteristics.At the same time,it is pointed out that the current measurement equipment is relatively large in measurement length.The object has the disadvantage of low roll inertia accuracy.Secondly,according to the characteristics of the projectile and missile model,the complete measurement principle of the quality characteristic parameter measurement system is analyzed from several aspects such as the principle of mass measurement,the principle of mass center measurement,the moment of inertia and the principle of inertial product measurement,and a detailed test scheme and test procedure are formulated.Using the graphic method,the calculation of the longitudinal centroid based on the small angle flipping method is given.Through the vibration-torsion comprehensive measurement method,direct measurement of the yaw moment of inertia,roll moment of inertia and pitch moment of inertia is achieved,and the disadvantages of the single torsion pendulum method in solving the three moments of inertia using simultaneous equations are solved.At the same time,the theoretical calculation formulas for measuring the moment of inertia of the torsion pendulum method and the vibration method are deduced under the actual tooling conditions.Again,according to the principle of quality characteristic parameter testing and measurement methods,quantitative analysis of mass error,center of mass error,moment of inertia error,and inertia product error from quality measurement,fulcrum position,angle measurement,period measurement,installation position,etc.,respectively.The objective function of the comprehensive measurement error for each test item was deduced and simulated.Then,based on the measurement principle of the quality characteristic parameters and the theoretical error analysis results,a three-dimensional modeling of the integrated test bench is performed according to the measurement requirements of a certain type of bullet and arrow model,and the designed weighing platform,turning platform,and twisting platform are designed.The vibratory table realizes the measurement of mass center of mass,yaw moment of inertia,roll inertia,and pitch inertia.Finally,standard parts with all known quality parameters are used for calibration and measurement,and the test results are calculated and analyzed.Two kinds of mathematic models based on theoretical error analysis and least squares method are used to compensate for errors and compared.