Utilizing electrostatic force and mechanical vibration to obtain regolith sample from the moon and mars

To realize reliable and autonomous sampling of regolith on the Moon and Mars, the authors have developed a unique sampling system that employs electrostatic force and mechanical vibration for the capture and transport of particles. A high alternating current (ac) voltage is applied between parallel screen electrodes mounted at the end of the sampling tube. Regolith particles on the surface of the Moon and Mars are captured using an electrostatic force, and they are passed through the openings of the screen electrodes. The captured particles are then transported through a tube to a capsule against gravity utilizing mechanical vibration. Experiments demonstrated that regolith is captured for a short time period if the open end of the sampling tube is immersed in the regolith layer. The captured regolith is transported upward through the inclined sampling tube against gravity. However, if the regolith in the vicinity of the fixed tube is depleted, the transport rate is decreased. The regolith particles are captured by the alternative electrostatic force. The capture rate increased with increases in the applied voltage. The electrostatic capture supplements the vibration capture, but the total collection rate is dependent on the amount of simulant captured at the tube entrance, or capture-controlled.