From a dark Houston control room, Rafael Guedes watched on a monitor as a robot took charge of a drilling rig in a North Dakota oil field, locking out the human operator.Glowing red boxes lit up the screen as an artificial intelligence program took over the distant Nabors Industries Ltd. rig, beaming instructions by satellite and making split-second decisions to drill through the rock as smoothly as possible. Guedes, the company’s director of performance tools, estimates the program from Corva L...