DTH technique was used in well drilling exclusively to dig, accurate, vertical bores, and rotary drilling was used to turn the hole. The Directional DTH system, patented by Atlas Copco, was first used.
[pdf] Combining Nabors proprietary Smart Suite of automated drilling software with Canrig® robotics on the PACE®-R801 creates an unmanned rig floor that removes crews from red zone areas and delivers consistent, predictable drilling performance. Video from the first well is available here, PACE®-R801.
[pdf] This step-by-step guide provides detailed instructions on how to build your own homemade water well drilling rig, empowering you to save money and learn the world of DIY water well drilling equipment, including hand augers, portable drill rigs, and hydraulic drill rigs.
[pdf] 
