Error Analysis Of The Similar-scara Parallel Manipulator With Mobile Platform Rotating Continuously

In this article, with regard to a three-DOF similar-SCARA parallel manipulator with mobileplatform rotating continuously, after the mechanism configuration, kinematical analysis and soon, it deals with the static accuracy problems which is came to mobile platform of the parallelmanipulator for the first time, mainly including geometric error model and error analysis of thesimilar-SCARA parallel manipulator mechanism. The main researching contents of the paper areas follows.First of all, by comparing the different error modeling method of the robot mechanism, inthis paper, with regard to the similar-SCARA parallel manipulator, points out the deficiency ofthe existing modeling methods, and puts forward a new error modeling methods, namely:categorical describe geometric error which is came to mobile platform of the parallelmanipulator and owing to manufacturing and fitting, and then analyze the effect of the geometricerror on the mobile platform output end, through the modeling and calculation, finally get theterminal error of every bar. This method without any differential operation, the process is simpleand physical meaning of the error model is clear, and it could analyze a variety of terminal errorwhich is generated by original error.Secondly, make use of differential superposition principle, linearly superpose geometricerror corresponding terminal error of every bar, and find out the terminal error correspondinginfluence coefficient, the study found that terminal geometric error of the robot is on theinfluence of pose parameters and geometric parameters, and geometric parameter error and so on.In order to show the incidence with respect to geometric parameter error on terminal geometricerror of a rod, could analyze the relationship between pose parameters and geometric parametersand the influence coefficient of terminal geometry error of the robot directly. Therefore, theapplication of error effect coefficient for error analysis of similar-SCARA parallel manipulatormechanism has an important meaning, at the same time, also abounded the concept andapplication scope of error influence coefficient in the field of robot research.Finally, to begin with the influence coefficient, analyze the relationship between poseparameters and geometric parameters and error influence coefficient of the robot throughestablishing graphs with the software of MATLAB, find the error singular point, puts forward end manipulator of mobile platform should adopt two points to take and put things, avoid errorsingular point, it has practical guiding significance to robot operation.