Optimal Motion Planning of Mobile welding robot Based on multivariable Broken Line Seams

This paper focuses on the motion planning analyses for a custom built mobile welding robot system. The robot which consists of a vehicle and a manipulator arm can turn itself, while the torch at the end of manipulator moves along a desired path simultaneously. For the broken line seams, the angle of the two seams is nondeterministic, which is an input variable. The minimum angle has been calculated and proved through mathematical analysis. Another input variable is the height difference between the seams platform and the vehicle. It determines the y-direction difference between vehicle centre in initial position and the first seam. Through optimization analysis, the relationship between all input variables and output variables is obtained. Curve fitting and surface fitting are used to establish the fitting function. Through the function, output parameters can be accurately obtained from determined input variables. It is applied to the welding experiments.