Here is the full list of all 35 Droid Assault achievements.
Got Red Alert twice on one level
Fried 100 robots
Destroyed 100 robots with the disruptor
Crushed 25 robots in doors
Defeated a boss with only a Sec Level 1 droid remaining
Escaped with 0 hitpoints and no squad
Started a level with 8 droids, finished with only 1
8 droids in ascending security order
Command a full squad of 8 droids
Completed Arcade Missions
Captured 3 9-series robots in same squad
Captured the Ultimate Droid
Achieved security level 8
Achieved security level 9
Defeated Level 40 Boss
Achieved security level 7
Maximum Overdrive buff
Maxed every buff on a droid
Everything-proof and maxed-buffs droid
Maximum Recharge buff
Maximum Armour buff
Maximum Damage buff
Maximum Battery buff
Got Red Alert status
Flame, laser, and disruptor resistant droid
Defeated Level 30 Boss
Achieved security level 6
Defeated Level 20 Boss
Achieved security level 5
Buffed a droid in every aspect
Defeated Level 10 Boss
Achieved security level 4
Achieved security level 3
Achieved security level 2
Achieved security level 1