The first phase of the competition was completed in 2015, and the relatively simple task was to present the architectural effects of each team's proposed building. In the second phase after that, the team began exploring materials - and the structural components that these materials will be used to build - to make these habitats viable. Now we have seen the end of the third phase. The final three teams in May will challenge the actual printing of small-scale models of their habitats. NASA requires that they build the whole process on their own.
Then came the Zopherus team from Arkansas. The team won second place with a prize of $33,000 for its 3D printing design. The organization envisions a mobile printer that can automatically drive to the right place and build a structure, then wander to another place to continue printing a community.
Finally, there is the Mars Incubator team from Connecticut. Its design includes several pentagonal and hexagonal structures, which can be combined to form spheres of different sizes. Each can then be connected through a short docking pipe, and different parts can be used as air gates, hydroponic laboratories, etc.
Previous experiments have included testing whether the printed samples designed can hold water or withstand simulated meteorite impacts. In addition, extreme temperatures of freezing and thawing were measured based on the building parts of each team (without human intervention).
NASA will award these teams $800,000 in early May in Pioria, Illinois, and announce the winners.