The Headmasters were a line of toys from the Transformers. They would consist ot two robots; one large robot who transformed from a vehicle or creature into a headless robot. The other robot, which was way smaller, would transform from humanoid form into the larger robot's head. The second "robot" was actually a human in removeable armor that made them look like robots. These suits also gave them increased strength and other powers.

In Transfomrers lore, the theory was that a Transformer, in vehicle mode, would react much quicker with a human pilot/driver at the controls.

Or you could say that Hasbro, the maker of Transformers, was running out of ideas. Either way, more than a dozen Headmasters were made. The idea spun off into Targetmaters, which had human pilots in armor who would turn into guns; and Powermasters, which featured human pilots in armor who would turn into the vehicle's engine. Now there's something any human would be proud of.