These three adorable little auomata can be found in the Terralava dungeon.
I am not sure if they can all be found in the same subdungeon or on different subdungeons. I added where I found them.
All can be found in a room that has a blue barrier within the dungeon. You need three different visits at the minimum (which you will most likely do anyway) to this dungeon to get the three different automatons. It seems to be a chance event, but is quite regular so don't worry.
After killing all the bots hurting our little automaton friends, go up to the automaton and press b to save it.
Here is the order in which I found them in, it could be different for you:
1. (I found it in the Industrial district of terralava) The first one will need some saving from bullies. You will help the little guy out and then see a short little scene in a room with the creator.
2. (found in Industrial district of terralava) The second one is a little more difficult, you will come across a room full with shot up robots. You don't know who's done it, but the enemy of your enemy is a friend. Search around this floor for another room where you will find the little guy taking down more robots, but it'll need some help. DO NOT GO TO THE NEXT FLOOR, otherwise you will miss him.
3. (I found it in the Area 30 of terralava) The one in need of your help the most. He will be behind another blue barrier being bullied by two other bots and being drained.
After a cute and sad little cutscene back at the house this achievement will unlock.
If you have anything to add please add a comment and let me know :)