Research On Pendulum Impact Test Platform And Its Impact Response

The requirements for the reliability of electronic equipment are constantly increasing with the development of electronic information technology in modern warfare.As an important method for reliability research and quality inspection of military products,impact test is a significant test method for improving and guaranteeing the quality of military electronic equipment.There are some limitations in the existing impact test machines of slide-type and drop-type that causes two or more shocks or has poor applicability or lacks of highly precise testing and analyzing system,etc.Therefore,this treatise focuses on the test method of pendulum impact and launches research on pendulum impact test platform and its impact response.First,this treatise studied the impact response model of pendulum impact test.Elastic cylinder and hemisphere are used as semi sinusoidal generators.Plastic cone is used as final peak saw tooth wave generator.The stress-strain relationship of cylinder buffer’s response model is established on Hooke’s law.The stress-strain relationship of contact model between two spheres is established on elastic half-space theory and Hertz theory.Then the stress-strain relationship of hemispherical buffer’s response model is established if a sphere is regarded as infinity.The stress-strain relationship of cone buffer’s response model is established on volume invariance theory while the stress value is simplified to the yield limit in the process of yield and reinforcement during plastic deformation.The impact response model is established according that the relative velocity of the pendulum with the buffer is equal to the shortening rate of the buffer.The maximum strain and response acceleration and impacting time are obtained by calculus operation.It is used to analyze the influence of swing angle,buffer size and mass of pendulum on impact response.Secondly,IEPE acceleration sensor is used to collect response acceleration signal and then to supply constant current exciting and signal conditioning by constant current adapter.The acceleration signal is transmitted to the test software by the acquisition card.The functions of acquisition,display and analysis of acceleration signals are realized by the test software written by LabView.The coefficient of assessment is used to illustrate the tolerance of sampling curves,which include Euclidean coefficient and cosine coefficient.When the evaluation coefficient satisfies the tolerance requirement,the impact response meets the impact requirement.Otherwise,the guidance for impact test will be made by test software according to the size of the evaluation coefficient.Finally,the small pendulum impact test platform was set up to carry out impact test and analysis.The law of impact response is obtained through single factor comparison experiment that analyzed the influence of swing angle,buffer size and mass of pendulum on response acceleration peak and impacting time.Missile impact test was simulated in the small pendulum impact test platform according to the law of impact response.The test results meet the requirements of impact response and tolerance.These tests have fully verified the feasibility of pendulum impact test.And this treatise has a positive effect on the development of impact test.