Updated: April 14, 2021

Alternations to the Robby Costume:

The repeated falls may partially account for the three substantive alterations to the Robby costume prior to its use on Lost in Space in 1966. There were: a new dome, new arms, a new chest box, and a dash of yellow paint for the episode "Condemned of Space" (1967).

The New Dome:

In the plastic dome seen in Forbidden Planet and the Invisible Boy, the bottom back rim of the dome that runs along the top of the cooling vents is scalloped. A more dramatic sawtooth pattern is especially apparent in the stepped rise in the dome at the beginning of the cooling vents, just below and to the right of the ear sensors and just behind the mouth opening. The new dome used in Lost in Space has abandoned this scalloping and has substituted straight edges.

Invisible Boy (1957)

Lost in Space, "Condemned of Space" (1967)

Invisible Boy (1957)

Lost in Space, "Condemned of Space" (1967).

Lost in Space, "War of the Robots" (1966)

The New Arms:

Robby's arms are similar in conception to the arms of the Lost in Space robot, but there are major differences. Instead of collapsible rubber bellows, Robby's arms are a series of interlocking rings held together by what appears to be rubberized cloth. These rings are found between the wrists and the ball joint that partially protrudes from the shoulder. In Forbidden Planet and the Invisible Boy, there are only 4 rings per arm and usually only three rings are visible. It is not known whether these rings can be fully retracted into the ball joint out of which they emerge. Clearly, some retraction is possible.

For Lost in Space, however, Robby's arms were more than doubled in length. Instead of three rings, Robby now has at least seven visible rings. In some shots, I have counted eight rings emerging from the ball joint. While there may have been many reasons for the change in arm length, a practical advantage of the increased length is a great range of arm motion and an enhancement in Robby's ability to pick up and carry objects.

Forbidden Planet (1956). In this publicity shot, one can count four arm rings.

Lost in Space, "War of the Robots" (1966). In this screen grab, one can easily count seven rings in Robby's left arm.

Invisible Boy (1957). In this publicity still, the standard minimum of three rings are visible.

Lost in Space, "War of the Robots" (1966). In this screen grab, one can count seven rings in Robby's right arm.

Invisible Boy (1957). This is an especially good shot of the fabric liner behind the rings.

Lost in Space, "Condemned of Space" (1967). In this screengrab, one can count six rings, indicating that retractibility of the arms was possible to a certain extent.

The New Chest Box:

For reasons unknown, Robby's chestbox was redesigned for Lost in Space. First, the box insert was installed upside down. Second, the "piano keys" that pulsed alternately were masked over with a metal plate. In "Condemned of Space" (1967), this plate was colored red. It is possible that it was also red in "War of the Robots" (1966), but this is difficult to acertain because it was filmed in black and white.

Third, the function of the "analyzing hopper" door was changed. In Forbidden Planet, this apperture opened up to receive items for analysis. In Invisible Boy, the aperture opens to reveal a central circular socket used to hook Robby up to the evil super computer. In "War of the Robots" (1966), the upside down hopper opens up to reveal that the central socket has beentransformed into the barrel of a laser gun. In "Condemned of Space": (1967), the "analyzing hopper" never opens.

Fourth, and finally, for both episodes of Lost in Space, the two rotating censors have been replace with a copper plate with three glass panes behind which pulsating lights are engaged in a chase sequence.

The Yellow Paint:

The simplest and perhaps the most obvious alteration that Robby underwent for "Condemned of Space" (1967) was the addition of a few yellow stripes: two along each side of the mouth; two around each arm; one around each wrist; one around each knee; and one around each foot. The yellow stripes coordinated nicely with the yellow stripes on the outside of the prison ship, the Vera Castle, where Robby job worked as a prison guard.