The Lunar Ice QUest Innovative Design (LIQUID) is a mission designed to excavate, refine, and transport water-ice in the polar regions of the moon. Excavation is completed by three 200kg class bucket ladder rovers and transport by two 100kg class rovers. LIQUID is able to produce 29,000kg of water-ice within a 1 year mission duration.
The concept of operations for Lunar Ice QUest Innovative Design (LIQUID) begins with landing the necessary equipment on the lunar surface. This is performed by two landers which land on a constantly sunny area for power generation and a permanently shaded region (PSR) for mining and water extractraction. Lander 1 (Sunny) carries the NASA Delivery Point infrastructure, the NASA Power Station and Power Transmission hardware. Lander 2 (PSR) contains the modified NASA Water Extraction Plant along with three Excavation Rovers and two Transport Rovers for a total of 2000 kg of payload.
Phase 2 consists of the 3 Excavation Rovers excavating the ice-free regolith layer consisting of the top 20 cm (Fig. 2). Excavation rovers move to the excavation site and remove this layer with 3 cm deep passes over a 15 x 15 m area that will form the Excavation Site. Collected dry regolith is unloaded approximately 10m away. This process takes 18 days to complete.
The five rovers will perform tasks in 2 parallel cycles. Cycle 1 is the excavation cycle, Cycle 2 is the ice transport cycle. Each cycle consists of several tasks. During cycle 1 a mining rover begins by being loaded with 150 kg of dry regolith that the water extraction plant has just processed. It then begins to travel to the mining area 250 m away. During transit, it slowly dumps the dry waste regolith in a thin strip out of it’s tailgate. Once the mining rover arrives at the mining site it excavates 150 kg of icy regolith to fill its hopper. The rover then returns to the water extraction plant, once at the plant the rover begins to unload while charging. Now fully charged, the rover can repeat the entire process. With three rovers the processing plant can be filled at an average rate of 100 kg/hr to match it’s processing rate of 100 kg/hr. During cycle 2 transport rovers begin by loading with ice cubes at the water processing plant. Ice cubes were chosen to be the state in which water is transferred to avoid heavy vessels and pumps needed to manage liquids. The rover then transports a hopper load of 27 kg of ice 4500 m to the delivery point where it unloads it via a tailgate similar to the mining rovers. Finally it returns to the processing plant to charge. The cycle then repeats. These cycles repeat until a 15x15x1 m volume of regolith has been excavated which corresponds to 10,000 kg of water with a 1.2 safety factor of material.
Upon successful completion of Phase 3 and delivery of the required 10,000 kg of water ice to the Delivery Site, the dry regolith excavated and set aside in Phase 2 is collected by the Excavation Rovers. It is used to cover the now exposed 10% regolith layer to thermally insulate and protect this layer from sublimation.
When operations continue into year 2, the Excavation Site can be enlarged with an adjacent pit and water ice production can continue as needed or increased as desired.
The rovers have an expected lifespan of 3 years without maintenance after which the rovers would be parked in a parking location waiting to be recycled unless they could still operate. It is expected that new vehicles would be transported to take over the tasks. Perhaps different excavation technologies will have been developed and could effectively excavate the variably cemented 10% icy regolith, which has been preserved in Phase 4.