No abstract

Dynamic penetration test by a penetrator is an important detection method for lunar exploration. The analysis of the dynamic penetration properties of the penetrator significantly helps to design the penetrator structure. In this article, the dynamic penetration mechanical model was established according to soil mechanics. Then, the discrete-element simulation model, which was established using the application program interfaces of the EDEM software, was used to simulate the penetration process. The penetration experiment demonstrated the accuracy of the dynamic penetration model and the discrete-element simulation model. This study of dynamic penetration model of a penetrator may provide technical support to the deep space exploration.

The rocks on extraterrestrial objects contain plenty of original geological and biological information. Drilling and sampling are an essential task in lunar exploration or future explorations of other planets like mars. Due to the limitation of payloads, energies, and drill pressure, the investigation of a lightweight and low-powered rock-drilling device is crucial for explorations of distant celestial bodies. The ultrasonic drill driven by piezoelectric ceramics is a new drilling device that can adapt to the arduous space rock-drilling tasks in weak gravitational fields. An ultrasonic drill suitable for mounting on a planetary rover’s robotic arm is developed. The ultrasonic transducer’s energy conversion from electric energy to acoustic energy and the energy transmission from the horn’s high-frequency vibration to the drill stem’s low-frequency impact motion are analyzed to guide the design of the drill. To deeply understand the percussive drilling mechanism under high-speed impact, the interaction between the drill stem and the rock is simulated using LS-DYNA software. Drilling experiments on rocks with different hardness grades are conducted. The experiment results illustrate that the ultrasonic drill can penetrate into the hard rocks only taking a force of 6 N and a power consumption of 15 W. The study of ultrasonic drill will provide a reference method for sample collection of extraterrestrial rocks.

No abstract

No abstract