| As the core of spacecraft power,the precise control of engine thrust is very important for controlling the attitude and improving the accuracy of the target.With the rapid development of modern Aeronautics and Astronautics,the reliability of engine is also getting higher and higher.Rocket engines relying on the chemical energy of solid propellants as energy sources are called solid rocket motors and have been widely used as power devices for various aircraft such as rockets and missiles.Therefore,before the engine is put into use,a test system is required to judge the performance of the engine.In this paper,a large vertical thrust piezoelectric test system is developed for the six-dimensional force calibration of rocket engines.The test system is characterized by high rigidity,high natural frequency,and large range,which ensures the accuracy and reliability of the calibration of the six-dimensional force.The advantages of piezoelectric sensors in thrust test are introduced,and the layout of dynamometers is analyzed in detail.The theoretical principles in the calibration process were introduced,including the definition of the relevant parameters of the thrust vector,the theoretical model of the test system,and so on.The key technologies and difficulties that need to be solved are put forward to provide the basis for the structural design of the subsequent test system and the design of the calibration experiment program.According to the solid rocket engine’s shape and size and work characteristics,the structure of the test system is designed.The test system is a vertical structure.On-line calibration,the engine nozzle is upward.The test system can realize the calibration of the rocket engine force and moment,and design the real engine thrust vector test structure to verify the performance of the test system.Using ANSYS Workbench to parametrically analyze the design process of the test system’s core structure supporting circular table,and analyze its stiffness and natural frequency at the same time.A test system was designed to calibrate the forces and moments.Experiments have found that the main error is less than 0.3% and the lateral error is less than 3%.In order to reduce the influence of the inter-channel interference on the test accuracy,the data is processed by the compensation matrix through the interference,and the compensation effect is obvious.Simulation vector force loading(including 45°loading and diagonal loading)tests were performed to verify the performance of the test system.After testing,the developed vertical thrust piezoelectric test system has high accuracy,high natural frequency,and high stiffness,which meets the test requirements for rocket engine force and torque. |
