Editing Engine Heart (section)

====The Ark====
The gist of it was that robots were sent to Mars to build infrastructure for humans. After the Event the robots are left to their own ends. Two camps of robots, one American and one Chinese, have to decide what to do. They can fight each other or they can work together. Some robot might get the idea to use the crew return rocket to send robots back to Earth. But, they only have a short window to launch when the planets are in the right configuration. If they miss it they have to wait 18 months to try again.
There are lots of different kinds of robots that could be on Mars. Rovers of course but also mining robots that dig up subsurface ice to make into liquid oxygen (rocket fuel). Weather robots that float on balloons for months. Transport vehicles. Humanoid cybershells meant to be teleoperated when the colonists don't want to suit up to go outside.

If Mars is too standard there is also Saturns moon Titan. Due to lower gravity but almost standard atmospheric pressure it would be possible to have real working ornithopters. The moon also has something called cryovolcanoes. These look like normal volcanoes except they shoot out cold water and ice. These robots could also hook up with gas mining robots from Saturn. They could hitch a ride with a Helium-3 tanker on its way back to Earth.

----