Cylon Centurion battle robots from the 1978 Battlestar Galactica.
The Cylons were designed by illustrator Ralph McQuarrie and costume designer Jean-Pierre Dorleac. Initially, Cylons were supposed to be reptiles in armor. But ABC nixed that idea, thinking that the slaughter of Cylons during the show would be too violent. (Almost no human beings die on screen.)
The helmets meant that actors almost could not see. The armored arms, legs, and shoulders meant that actors were very limited in their range of movement as well. The bulky black gloves used for hands also meant that it was difficult to keep a grip on something, even something as large and bulky as a rifle or gun. Actors routinely fell down, tripped, or ran into things. After the first three episodes ("Saga of a Star World", "Lost Planet of the Gods", and "Gun on Ice Planet Zero"), the appearance of Cylons was choreographed so that few objects would lie in their path, actors could move in a straight line, and so on. Over time, the Cylons disappeared from the show entirely!
Filming the Cylons was quite difficult, as the shiny armor reflected light and created flares in camera lenses. Additionally, the mirrored armor meant that sometimes crew could be seen in the Cylons' armor. To reduce these problems, most Cylon scenes occur in dark or smoky rooms.
Dorleac won an Emmy for Best Costume Design.