|ASnic frequency||60 - 1000||Hz|
The Auto-Gopher employs a piezoelectric actuated percussive mechanism for breaking formations and an electric motor to rotate the drill bit and capture powdered cuttings. It incorporates a wireline architecture; the drill is suspended at the end of a small diameter tether that provides power, communication, as well as structural support needed for lowering and lifting the drill out of the borehole.
Thanks to this unique architecture, the maximum drilling depth is limited only by the length of the tether. The wireline operation used on the Auto-Gopher removes one of the major drawbacks of traditional continuous drill string systems—the need for multiple drill sections that can add significantly to the mass and the complexity of a deep drill. As such, the Auto-Gopher system mass and volume can be kept quite low for shallow or deep holes.
While drilling, numerous sensors and embedded instruments can perform in situ analysis of the borehole wall. Upon reaching a preset depth, the drill is retracted from the borehole, the core and/or cuttings are removed for detailed analysis by onboard instruments, and the drill is lowered back into the hole to continue the penetration process.
Auto-Gopher can be deployed from a variety of platforms, providing deep subsurface access with a small surface footprint. This technology also enables new in-situ analysis applications through integration of in-drill sensors — in essence, bringing the instruments to the deep subsurface sample
Describes the project, it's design, and fabrication & testing.
Describes the ultrasonic/sonic driller/corer description and modeling, the gopher, tests & conclusions.