Optimization Design And Characters Analysis Of The Servo-hydraulic Triple Channel Testing Machine

Material testing machines are divided into two types:static testing machine and dynamic testing machine. Static testing machine is applied to test the performance of material static mechanics, such as the yield strength and tensile strength of the metal. The dynamic fatigue testing machine is specialized in the capability of dynamic mechanics, such as the fatigue strength of material, crackle expansion capability and the dynamic stiffness of the parts. No sooner did the servo-hydraulic universal testing machines, which are developed from the servo-hydraulic technique, become the powerful means to research the material fatigue performance and dynamic capability as they come out to the market. They are applied widely in both international and domestic dramatic research field. The tensile-torsion complex loading dynamic testing machine and tensile-bending-torsion multi-channel complex-loaded testing machine meet the requirement of testing the dynamic performance and fatigue performance of complicated materials, and simulating the working state of the parts.Servo-hydraulic triple-channel testing machine is one type of multi-functional machine which can be use on tensile compression, bending and torsion loading. This machine has three actuators which are used separately to load tensile, compression, bending and torsion on testing objects. Multi-channel control loading is a complicated technique, and it is more complicated to load multiple forces on one part.The servo-hydraulic triple channel testing machine is a type of fully new complexly material-loading testing machine which is developed specially for Bei Hang University. There is some defection due to lack of such design experience and similar produces both internationally and domestically. The content is combined with the problem occurred in practice. It starts from the provided problems to analysis the disparities between the design target and the specimen machine, then put forward the load frame mechanic structure optimization program combining with the advanced analysis software. There is some creation and deeper research in this content.1) Force closed-loop frame structure and force open-loop frame structure are put forward according to this type of machine.2) Optimization program is provided based on the character of bend loading and the defections of the fixture in existence.3) Point out the effect of the system cause by the stiffness. Put forward the optimized measure from both load frame and hydraulic station.4) Perform simulation analysis to get the good result.In conclusion, The advantage of force closed loop structure is displayed by modeling, analyzing and comparing the frame through finite-element method. The life-span is also improved by optimizing the fixture to eliminate the potential safety problems. The performance after optimizing is simulated through advanced analyzing software. The simulation effect meets the design requirement through the main loading channel. Solutions for the former steps provide a theory base and practical schemes for the following ones. Analysis, design, calculation and simulation experiences are accumulated about multi-channel & multi-direction loading.