Sweeps are the minions of Scourge created by Unicron during The Transformers: The Movie. Sweeps are visually indistinguishable from Scourge himself, although it was demonstrated through the course of the third season of the animated series that Sweeps do not necessarily have identical voices.
Although only a few are seen initially during The Transformers: The Movie, there appears to be an inexhaustible supply of them during the course of the cartoon.
The Sweeps are by far the favorite cannon fodder of Galvatron, being beaten or destroyed in any number of abysmal ways. These ways include being thrown into the great beyond, lava pits, and into the path of an energy-mongering transorganic vampire monster.