Design And Research Of Feeding Support System For Hypersonic Aircraft Model

The wind tunnel blow test is a test that must be carried out in the development stage of the new aircraft.The wind tunnel blow test is a test that must be carried out in the development stage of the new aircraft.Through this test,the performance of the aircraft can be mastered,and the design of the aircraft is guided[1].The model feeding support system is the key supporting equipment for wind tunnel test.It is used to provide feeding and supporting for the test model.According to the test requirements,the model achieves various attitude adjustments during the test,which is closely related to the wind tunnel test.The wind tunnel model is fed into the support system to simulate the motion of the aircraft in the air according to the relative motion principle,and then to measure the aerodynamic characteristics of the aircraft.With the development of technology and national defense concepts,hypersonic vehicles have become the focus of national development.China is also stepping up technical research and equipment development in related fields.The structural rigidity and motion accuracy of the feeding support mechanism under heavy load environment are the main difficulties.In the past,the environment in which the model was fed into the support system was sub-wind or cross-wind speed,and the structural performance requirements of the model were low.In this paper,the model is fed into the support system in a hypersonic environment,and its configuration design is completed.It is studied from the aspects of error analysis,the optimization of important component and trajectory planning.The specific research contents include:(1)The domestic and international research status of the wind tunnel model feeding system is summarized.Combined with the specific requirements and working environment of the subject,the configuration analysis and design of the wind tunnel model feeding system is carried out.Through the comparative analysis of the three configurations,a high-rigidity,low-blockage series four-degree-of-freedom feeding support mechanism designed by the principle of leverage is proposed.And the design and the stress analysis of each component of the new configuration were carried out.(2)In order to ensure the accuracy of the motion model of the support system,the kinematics and the static error analysis of the four-degree-of-freedom mechanism were carried.The forward kinematics equation is established by using the D-H method to feed the support mechanism,and the kinematics equation is verified by the solution of the motion space.Based on this,the static error model and the error reliability analysis model of the mechanism are established.Based on the reliability evaluation,the Monte Carlo method was used to study the influence degree of each joint parameter on the mechanism precision error,and The source of error that has a greater impact on the organization has been identified..The end pose error is analyzed to verify the rationality of the mechanism design.(3)In order to balance the bearing stiffness and the rapid response performance of the system,the moving platform of the model feeding mechanism is taken as the research object,and the finite element analysis software is used as the tool to optimize the weight of the research object according to the specific working conditions.The structure is improved according to the manufacturing and assembly requirements,and the weight topology of the moving platform is completed.Based on this,the size optimization is used to further reduce its quality and improve its performance.(4)Heavy load and rapid movement are characteristics of Rapid movement.In order to ensure the performance of the model's motion process,the spatial trajectory planning of the model's respective degrees of motion is performed at the acceleration layer.For the two conditions of feeding and not feeding,the two innovative planning methods of symmetric combined sinusoidal and asymmetric combined sinusoidal are proposed to achieve the comprehensive motion performance of each joint.Time optimization of the trajectory curve according to actual speed and acceleration requirements.Finally,the joint trajectory planning curve was simulated and verified based on Adams software.