Research On Form Tolerance Evaluation System Of Mechanical Product Based MATLAB Optimization Toolbox

Form tolerance is vitally important to the quality of machinery parts. And the study of form tolerance measurement theories, as well as its evaluation methods on CMM, is of great significance for the engineering application. A new evaluation method based on the optimization toolboxes of MATLAB is presented in this paper in accordance with the definition and evaluation criterion of form tolerance, as well as the corresponding engineering application software. The major achievements and conclusions are given in the following:(1) A mathematical (numerical) model is set up for optimization solution of the form tolerance evaluation in accordance with the definition and evaluation criterion of form tolerance stipulated in GB1183-80 (straightness, flatness, and circularity). Besides, the model can be also used to facilitate the optimization solution by simplifying the high dimensional form tolerance (cylindricity and random direction straightness).(2)According to the requirements of Structured Programming and Object Oriented Programming, form tolerance evaluation system is resolved into several subsystems: straightness evaluation system, flatness evaluation system, circularity evaluation system, and cylindricity evaluation system. Then, these subsystems are divided further into functional modules. And finally, the preliminary design is completed.(3) Solutions are given to the important problems in concerning with the form tolerance evaluation system, such as the selection and test of optimization algorithm,visualization of flatness and cylindricity, and the edition and romance of the graphics through MATLAB graphic handles. The final tests indicate the validity of the optimization algorithm.(4) In reference to the evaluation software in CMM, a friendly and effective human-computer interface is developed according to the requirements of the software program. Then, tests are made respectively on straightness, flatness, circularity, cylindricity evaluation subsystems to compare with the evaluation result of the CMM, which indicates a fairly good accuracy and efficiency of the results of the system.