"While using the Slug Cruiser, have vision of every room on the enemy ship without functioning sensors."
Earning this achievement requires a teleporter, as the player must have some of their crew (most likely Slugs) board an enemy ship to see the inside of it without functioning sensors.
An easy way to accomplish this is having a level 2+ teleporter, and teleporting your two inital slug crew onto an automated scout ship. With the upgraded teleporter, there's just enough time to teleport them out before they suffocate.
Alternately, many of the early-game pirate or rebel ships have layouts that can be completely viewed by only two carefully-placed slugs.
Also note that bomb weapons (such as the Breach Bomb Mark 1 of Layout A) will view any room a bomb is placed in, before it explodes.
The achievement can still be earned if the sensor system is installed on the Slug Cruiser, but the system must be either destroyed, fully ionized, hacked, or incapacitated due to a nebula.