Originally, Auto was designed entirely differently, resembling EVE, but masculine and authoritative and SECUR-T was also a more aggressive patrol steward robot. The majority of the robot cast were formed with the Build-a-bot program, where different heads, arms and treads were combined in over a hundred variations. The humans were modelled on sea lions due to their blubbery bodies, as well as babies.
Initially, Auto was designed with a distinctive appearance, drawing inspiration from EVE but with a more powerful and commanding presence, whereas SECUR-T was portrayed as a more forceful patrol robot. The majority of the robot characters were created using the Build-a-bot program, which allowed for an extensive range of combinations, resulting in over 100 variations. Humans were modeled after sea lions due to their robust bodies, as well as infants.