An Autonomous Self-Propelled System for Hard Rock Drilling

40457 APS Technology Several advancements are needed to improve the efficiency and accuracy of hard rock drilling. Of particular interest are bottomhole assemblies (BHAs) which can grip the borehole wall in order to provide a platform from which torque and compressive force can be applied to the bit and the direction of drilling can be continuously monitored and controlled. This project will develop a system with the following key components: hydraulically activated continuous bands to grip the borehole wall and provide both compressive force on the bit and forward motion; supplementary grippers to anchor the tool circumferentially and resist the reaction torque from the bit; hydraulic compensation to vary the drive force to the belts and allow differential directional control; and an accelerometer package to provide continuous monitoring of the inclination and orientation of the BHA, allowing the system to adjust the differential force, and provide autonomous correction of course. Phase I will study the feasibility of the mechanical and hydraulic components of the drilling system, and will analyze the forces and torques that can be generated. Phase II will be devoted to a detailed design of the entire system including sensors, controls, and electronics. Anticipated Results/Potential Commercial Applications as described by the awardee: By providing more efficient and accurate means of drilling high-angle and horizontal wells in hard rock, this system will allow development of fields and reservoirs that might not otherwise be feasible, and reduce the cost of development of other fields.