Application of Approximate Iterative Method on Section Precision Form- ing of Boom-type Roadheader

The decision of the inflection point is the key to ensure automatic section cutting precision using a boom-type road header. In this paper, cutting precision model was set up for the first time to trapezoidal section and a method determining inflection point is given. Considered the cutting head’ projection at section is elliptical with the cantilever’s joint variable. The relationship between ellipse curve and cutting section boundary was investigated, and thereby sets up the cutting precision model. Approximate iterative method is used to finding the optimal inflection point, of which takes the cutting precision as the objective function. Compared with the traditional process path planning method, the forming accuracy can be improved greatly and controlled within 1mm. Through MATLAB simulation, it is proved that this method is correct and valid.