Automatic cutting start-up and shutdown control method of roadheaders

To improve control precision of automatic cutting, by analyzing process path, key stages were found out which could give rise to roadway tunnelling direction error and cross section borderline roughness error. Different swing speed control methods of cutting arm were adopted in different stages which were slow start control at the beginning of cutting and slow stop control in each cutting step. Internal displacement sensors were used in driven cylinders of roadheader cutting arm to calculate the space position of cutting head and reflect swing speed of cutting arm. The method has been tested and verified on EBZ200 roadheader. The results indicate that slow start of automatic cutting could reduce vibration and prevent the change of machine body position and orientation; slow stop could reduce the control delay and improve roadway borderline precision.