Orbot

"Ergo, another repercussion of your hasty actions."

- Orbot

Orbot, also known as SA-55 or "Ergo", is the robot that appears in Sonic Unleashed as an assistant to Doctor Eggman. He usually points out Eggman's mistakes and often somewhat insults him because of them. He also constantly annoys Eggman with his non-stop talking. Orbot is a very small and round robot with an ability to retract into a travel sized sphere and glowing red eyes. His main function seems to be simply for relaying information to Dr. Eggman and making sure the processes of his plans are carried out correctly. His eye of efficiency may be what allows him to constantly criticize Eggman or inadvertently point out his flaws, however. Despite this it is shown that he does care to see Eggman succeed but doesn't skip out on the chance to be critical to the doctor and his feelings when he sees fit.

History
As of now Sonic Unleashed, is the only game Orbot has made an appearance in. He will be returning in Sonic Colors slightly more jaded then before.

Sonic Unleashed
His main role throughout the game was simply following his function. He relayed to Dr. Eggman the information he needed to know regarding how his plan was being carried out and did the mechanical processes that were needed to continue it. He was first heard in the first fight with the Egg Cauldron, and then first seen in a cutscene located in Mazuri where he ended up laughing at Dr. Eggman for being pegged in the face by a rock from a small child. He continued to act his usual critical and straight-forward way throughout the game up until the very end. In the final cutscene with Eggman he was seen being chased off into the sunrise by the angered Eggman after relaying to him how he had failed miserably and could begin anew.

Sonic Colors
He will be returning in Sonic Colors along with his counterpart, Cubot. Strangely his name has changed to "Orbot" and the top of his head is red instead of white.

Name
Orbot's name was not used in Sonic Unleashed. He was dubbed "Ergo" by fans because he frequently used the word ergo (meaning therefore, from the Latin) in his speech, indicating that he was making a conclusion.

Ian Flynn, head writer of the Sonic the Hedgehog comic book from Archie Comics, later revealed that the robot's name was SA-55, having seen the name in a script for Sonic Unleashed. (SA-55 is l33t-speak for sass.)

Orbot's real name was eventually revealed by ArchangelUK on Sonic City Blognik, an official Sega blog, based on an upcoming appearance in Sonic Colours.

Trivia

 * According to an interview with Mike Pollock he is voiced by Chris Collet who also voices some humans in the cutscenes and also acted as voice director in Sonic Unleashed.
 * Orbot will be appearing in Sonic Colors.