I have been thinking about this base as soon as I learned of the contest. The main questions I wanted to answer were: how do you protect from the martian environment (temperature shifts, radiation, winds, micrometeorites), and how do you do that with existing resources? By resources, I mostly mean water. Or to be more specific, the absolute absence of any sort of liquid binder.

The solution that made the most sense to me was putting something underground. This would provide much needed insulation from the rapidly changing environment and more than adequate protection from wind. I wasn't too sure how thick a layer of soil would be needed to protect from the radiation and meteorites, but I imagine that's simply a question of depth.

That is all nice and fine, until you think, how would you do that? Digging out cavities is difficult enough on Earth, let alone Mars. You have no real clue what is under the soil. Hitting a boulder could be the end of your day. Beyond that, any hole dug would have to be properly supported otherwise it would just cave in.

Then I thought, what if you could bury your base in a hole that's already there. Mars has plenty of craters. Why not land some capsules down and have a small army of robots bury the base. It could take years, sure, but the equipment needed to do so is simplistic and could be remotely controlled. (base bidron..... by-drone)

Bots: In the models, I made the little buggy portion of each bot, with and attachment you can press in. I don't mean to have this specific functionality, it just makes a neat little toy like object.
The dozerbot is the core earth mover, featuring a bulldozer to move earth.
To maximize solar panels, solarBots have more solar panel than other bots which they can in turn act as a mobile charging station. I figure the dozerbot would use a larger amount of energy than it could safely generate on it's own.
The conveyorbot has a conveyor belt afixed to the top. This way the dozerbots can push dirt on the belt and then the belt can transport the dirt to the burying site.

Stage 1: Survey
A small contingent of bots scout possible base sites. If they don't find a proper site, they move on to another crater.

Stage 2: Site Prep
The army of bot level the portion of the crater that will have the capsules. Also, the bots will construct a ramp to easily gain access to the crater.

Stage 3: Prep Modules
The pre-made modules from Earth arrive and move into position against the crater wall. These modules have whatever is needed to sustain human life on Mars.

Stage 4: Blanket
During this stage the capsules are 'blanketed' with soil. This creates the protective layer to shield the capsules.

Once these stages are complete, then humans can land and enter the new base. I have no idea how long the process would actually take, but it is essentially accomplished using only solar power and does not require water.

stage1-4 make up the crater, sectioned into the 4 stages. Stage4 has the base modules already built in.

buggy + (dozer / conveyor / solar) make a bot. Print as many as you like. Print the attachments upside down.