The Study Of Linear Motor Actuator And Its Application In Micro Alternating Load

Testing of performance indicators such as material fatigue limit and fatigue life is crucial to product reliability,engineering quality,and personal safety.As the industry develops towards modernization and integration,almost all parts and components are subjected to high-cycle alternating load work.Therefore,performing accurate alternating load dynamic loading experiments on materials is to improve product reliability and ensure safety.the most effective way.Fatigue testing machines for fatigue testing of metallic materials in the market are relatively mature,but fatigue testing machines for non-metallic materials testing are quite scarce.This is the main problem to be solved in this subject.The driving device of the conventional fatigue testing machine mainly includes the following two forms: electromagnetic type and hydraulic type.The electromagnetic fatigue testing machine uses the principle of electromagnetic resonance.It needs to match the stiffness of the test piece to achieve the loading of the load,so it is not suitable for the loading test of non-metallic materials.The electro-hydraulic fatigue testing machine relies on the reciprocating movement of the hydraulic cylinder.When a load is applied,a large-load and low-frequency loading test is easy to achieve.As the frequency increases,the maintenance cost of the hydraulic cylinder becomes higher.In view of the above situations,this topic makes use of the advantages of good dynamic response,high efficiency,and precise control of linear motors,and proposes the feasibility idea of using linear motors as actuators in fatigue testing machines.Firstly,this article explains the concept of linear motor actuators,explains the principle,composition and structural design analysis of linear actuators,and references vector control,uses PID technology to perform closed-loop control adjustment,and MATLAB simulation of its dynamic loading model At the same time,the factors that affect the dynamic response in the system(the effect of the natural frequency of the force sensor on the dynamic response of the system)are checked.Secondly,the working device of the linear motor actuator was applied to carry out the structural design and dynamic analysis of the electronic high-frequency fatigue tester.A parallel bundling method of two linear motors was proposed to reduce friction interference.Thirdly,the control system of the electronic fatigue tester is designed.In this subject,only one driver is used to control the two motors,including the grating sensor and the Hall sensor.Using this control method,not only solves the problem of current unsynchronization that is easy to occur when two motors are used in parallel,and reduces the cost of scientific research,but also design the host computer control software to facilitate the use of the operator.Finally,the electronic high-frequency fatigue tester system constructed above was debugged and a dynamic loading experiment was designed to fully verify the feasibility of the application of the linear motor actuator in the application of a small alternating load from various aspects.This subject innovatively applies linear motor actuators to the application of small alternating loads,filling the gap of fatigue testing machines in the field of non-metallic materials.The minimum force value of the testing machine is 0.1N,so it is not only It can be applied in industry,and the fatigue life test of materials can also be carried out in the fields of biology,medicine,chemistry,etc.using the loading device of linear motor actuators.