NASA space technology is used to establish ultrasonically actuated bits for the construction, shallow mining, and demolition industries where an augmenter is developed for turning large and heavy rotary drills into rotary hammering drills that use low axial load and can be operated at ultrasonic frequencies to decrease the operation noise.
The technology is based on novel ultrasonic drilling capabilities that were developed at the NDEAA Lab of the NASA's Jet Propulsion Laboratory, Pasadena, Calif., with the objective to enable sampling mechanisms that can be operated in low gravity and extreme environments at the solar system.
The developed drills are driven by piezoelectric actuated percussive mechanisms that require low preload (as low as 10N), and can be operated using low average power. The drills were demonstrated to penetrate rocks as hard as basalt and in one of the designs it was made as light as 400g.
Significant improvement of the penetration rate was achieved by augmenting the hammering action by rotation and use of a fluted bit to provide effective cuttings removal. Generally, hammering is effective in fracturing drilled media while rotation of fluted bits is effective in cuttings removal. To benefit from these two actions, a novel configuration of a percussive mechanism was developed to produce an augmenter of rotary drills. A breadboard Percussive Augmenter of Rotary Drills (PARoD) was developed with a 6.4 mm (0.25 inch) diameter bit and was demonstrated to increase the drilling rate of rotation alone by 1.5 to over 10 times. Further, a large PARoD breadboard with 50.8 mm (2 inch) diameter bit was developed and its tests are currently underway. The PARoD is developed under a contract from the startup company, Placidus, and it is intended to establish a prototype for commercial drills that will be produced and marketed by Placidus.