a continuous feed drilling system and controller includes a head assembly having first and second chucks synchronized to rotate at the same rotational velocity . the chucks are independently moveable within the head assembly and their positions are measured by linear transducers . the controller causes the first chuck to engage with a drill stem and begin rotating and advancing . the controller uses the outputs of the linear transducers to determine the linear velocity of the advancing first chuck and synchronize the linear velocity of the first and second chucks . the controller then causes the second chuck to engage the drill stem and causes the first chuck to release the drill stem . the process is repeated , alternating the roles of the first and second chucks , thus creating a continuous drilling motion .