Demolition Trooper
From Metroid Wiki
The demolition trooper of the GFS are lightly armored, unlike the more commonly seen trooper. They carry explosives to destroy doors, walls, small ships, and other things. In Metroid Prime 3, were they are seen, you need 4 out of 12 demolition troopers to destroy a large door. They help you later by shooting pirate commanders. If 9 or more die you simply restart. They are black and yellow, they also have GF charges and a GF assault rifle.