A piezoelectric-driven ultrasonic/sonic driller for planetary exploration

Drilling is an essential task in unmanned lunar exploration and future explorations of other planets like mars. The traditional way is to adopt a rotary-percussive drill usually mounted on the side of probe or at the end of a robotic arm on planetary rover. Large penetrating force is needed to cooperate with rotary and percussive motion to overcome hard rock. Under the low-gravity environment, it is not easy to provide large penetrating force. As a kind of percussive drill, piezoelectric-driven ultrasonic/sonic driller (USD) employs piezoelectric component to transfer electric energy to mechanical energy of drill bit. Since piezoelectric component has wide temperature tolerance ability, USD can work well in harsh planetary environment. A USD is developed in this paper which has only one degree of freedom of percussive movement and the physical process of percussive drilling is modeled. Experiments indicate that the USD is a high-efficiency drilling device which is lightweight and requires low penetrating force.