Research On Prediction Of Straightening Stroke And Modeling Of Precision Linear Guide Rail

The precision prediction model of straightening stroke has great significance for automatic straightening machine which working mode is stroke controlling. This model will not only greatly improves the straightening accuracy and efficiency of straightening system, but also provides good expansibility for straightening machine.The research purpose of this paper is aiming at linear guide rails which sections are non-regular, establishing a precision prediction model of straightening stroke which is most suitable for automatic straightening machine control and it can provides theory basis for straightening system development.In this paper, take the LG series linear guide rails for example, a new way of establishing straightening stroke prediction model is proposed based on the combination of elastoplasticity theory, the finite element method and bending experiment. We establish the initial deflection-straightening stroke prediction models by above 3 different methods, we analyze them, then get the optimization precise prediction model, and put forward a new kind forecasting formula of stroke prediction which is simplicity and precision. At the same time, we establish the compensation database and forecasting formula table for reference and correction models which aiming at different straightening conditions and guide rails. Develop the straightening stroke calculation module which provides tremendous expansibility for control system.The main research contents as follows:Firstly, using elastic-plastic bending theory, based on the existing pressure straightening load-displacement model and straightening formulas of rectangular section bar, finding the relevant correction parameters, reforming the model of linear guide rail. We use MATLAB software to programming which greatly simplified the traditional calculating. And establish better applicability straightening stroke prediction model based on the relationship between initial deflection and straightening stroke.Secondly, by using finite element method, we simulate the loading-unloading process of 3-point reverse bending of guide rails in ANSYS software. It's material nonlinearity numerical analysis. Then we establish the straightening load-displacement model and propose deflection - straightening stroke model.Thirdly, we use experimental method to establish straightening model, doing bending experiment in precision equipment. Experimental data processing can reverse establish straightening stroke prediction model. We use polynomial fitting to get precise straightening stroke prediction forecasting formula which improves the currently linear empirical formulas.Finally, we compare above three stroke prediction model, establish straightening stroke prediction reference database and forecasting formula table of different types of guide rail. We take data fitting technology to correct and expand empirical formula. And develop the straightening stroke calculation module in LABVIEW platform for automatic straightening machine.