Here is the full list of all 16 Space Ripper achievements.
Collect 10000 gears
Get all upgrades
Collect 7000 gears
Get all Death Ray upgrades
Destroy Enemy Station
Survive during 46 waves
Collect 5000 gears
Destroy Crabotron
Get all Engine Upgrades
Destroy Saw Robot
Destroy Asterobot
Collect 3000 gears
Collect 2000 gears
Upgrade Death Ray
Collect 1000 gears
Upgrade Engine