Abstract: A drilling machine for angled drilling has a platform having a longitudinal axis and a transverse axis. The drilling machine includes a tower for holding a drill string and a tower interface assembly connected to the platform, so that the tower interface assembly moveably supports the tower. The tower interface assembly is selectively moveable to tilt the tower in either a plane parallel with the longitudinal axis of the platform, or to tilt the tower in a plane parallel with the transverse axis of the platform, so that the tilted drill string can perform angled drilling in either position. Further, the tower interface assembly is selectively moveable to simultaneously tilt the tower in the plane parallel with the longitudinal axis of the platform, and the plane parallel with the transverse axis of the platform.

Abstract: An apparatus for changing a drilling tool for a drilling rig is described, where the drilling rig comprises a drill tower supporting a drill pipe. The apparatus for changing a drilling tool has a drilling tool changer assembly moveable between a storage position and an exchange position, and the drilling tool changer assembly supports a rotatable carousel assembly. The rotatable carousel assembly is capable of being removed from the drilling tool changer assembly and capable of replacement on the drilling tool changer in the same angular position with respect to the drill pipe as when removed. The rotatable carousel assembly has a plurality of bit adaptors for holding drilling tools and is selectively rotatable to bring a selected drilling tool into coaxial alignment with the drill pipe when the drilling tool changer assembly supporting the rotatable carousel assembly is moved into the exchange position.

Abstract: A method is disclosed for semi-automatic or automatic control of a system for changing drilling tools for a drilling rig that includes a drill tower supporting a drill string with a drill pipe at a lowermost end, and a drilling tool changer assembly having a rotatable carousel assembly with a plurality of bit adaptors for holding drilling tools. The method includes removing a first drilling tool attached to the drill pipe and attaching a second drilling tool held in the rotatable carousel assembly to the drill pipe. The method may selectively be performed semi-automatically or automatically via a control system operatively coupled to the drilling rig.

Abstract: A track shoe for an endless track assembly has a base and an opposing hull. The hull of the track shoe has opposing sidewalls that are angled to meet at an apex, thus forming an inverted V-shape. The apex of the hull extends the width of the track shoe. Laterally-disposed ridges are spaced apart from the apex. and the height of the ridges tapers outwardly from the hull to form, respectively, a leading lip and a trailing lip of the track shoe. The track shoe may have upward bends at the ends of the width of the track shoe and optionally, may have secondary hulls.

Abstract: An apparatus for changing a drilling tool for a drilling rig is described, where the drilling rig comprises a drill tower supporting a drill pipe. The apparatus for changing a drilling tool has a drilling tool changer assembly moveable between a storage position and an exchange position, and the drilling tool changer assembly supports a rotatable carousel assembly. The rotatable carousel assembly is capable of being removed from the drilling tool changer assembly and capable of replacement on the drilling tool changer in the same angular position with respect to the drill pipe as when removed. The rotatable carousel assembly has a plurality of bit adaptors for holding drilling tools and is selectively rotatable to bring a selected drilling tool into coaxial alignment with the drill pipe when the drilling tool changer assembly supporting the rotatable carousel assembly is moved into the exchange position.

Abstract: A method for maintaining a penetration rate of a drilling operation, where the drilling operation is carried out by a drilling rig having a hammer drill apparatus. A reference penetration rate for the hammer drill bit is chosen. A starting depth of cut is computed from the reference penetration rate, the measured hammer frequency, and the drill bit parameters. The system measures the actual penetration rate of the drill bit and computes an actual depth of cut. From the actual depth of cut a target bit rotation speed is computed. The target rotation speed is compared to the actual rotation speed, and the rotation speed is adjusted up or down to set the bit rotation speed at a value that will maintain the target rotation speed, notwithstanding changes in hammer frequency or ground conditions.

Abstract: An apparatus for changing a drilling tool for a drilling rig is described, where the drilling rig comprises a drill tower supporting a drill pipe. The apparatus for changing a drilling tool has a drilling tool changer assembly moveable between a storage position and an exchange position, and the drilling tool changer assembly supports a rotatable carousel assembly. The rotatable carousel assembly is capable of being removed from the drilling tool changer assembly and capable of replacement on the drilling tool changer in the same angular position with respect to the drill pipe as when removed. The rotatable carousel assembly has a plurality of bit adaptors for holding drilling tools and is selectively rotatable to bring a selected drilling tool into coaxial alignment with the drill pipe when the drilling tool changer assembly supporting the rotatable carousel assembly is moved into the exchange position.

Abstract: A system for automatic calibration of an actuator, where the system has an actuator and a computer, and the computer further includes a PID controller. A sensor connected to the actuator transmits values representing the motion of the actuator to the input of the PID controller. The computer is programmed to compare the values representing the motion of the actuator to the output of the PID controller, thus outputting an error signal representing the difference between the output of the PID controller and the values representing the motion of the actuator. The computer stores this difference as a calibrated set point for the actuator when the difference is less than a predetermined amount. This calibrated set point is used to initialize the operation of a machine propelled by the actuator.

Abstract: A system and method for drilling a borehole using a drilling rig having a rotary drill bit includes monitoring one or more drilling parameters; determining whether the one or more monitored drilling parameters are within predetermined specifications for one or more of the monitored drill parameters; and, executing an exception control procedure for control of a drilling parameter. The exception control procedure receives an input sensor value associated with a drilling parameter and applies feedback control to establish a scaled error value that is used to compute a setting value for the drilling parameter. The drilling parameters controlled may include the rotation speed of the drill bit, the feed rate of the drill bit, the weight-on-bit, or rotation torque during retraction of the drill bit. A computer-readable database of specifications of drill bits may be provided as a part of the system.