Perceptor is a dedicated astronomer and physicist, one of the most brilliant scientists ever produced by Cybertron, and he is not interested at all in the mystical or supernatural. Much of the technology used by the other Autobots was due to his discoveries. There's a paradox named after him, presumably one he theorized. Distant and antisocial, Perceptor speaks with a bluntness befitting a scientist.
His alternate modes is a tank and a microscope.
After passing through the unstable space bridge, Perceptor and the Autobots aboard the Ark found themselves in the vicinity of a Cybertronian colony world called Velocitron. They located it in part thanks to a mysterious starmap projected outwards from Optimus Prime's chest by the Matrix itself. As a scientist, Perceptor had difficulty with the concept of a mythical artifact guiding their movements, but Velocitron proved to be real enough. He was part of Optimus Prime's initial landing team, who made contact with the planet's rulers, Override and Ransack. It was a time of great stress between Velocitron's rulers, and the Autobots' arrival from mythical Cybertron only exacerbated the situation. The planet's sun was unstable, and the speed-oriented engineers of the world had little scientific background in astronomy. Perceptor assisted the Velocitronians with their studies of the star, and successfully reactivated the planet's Space Bridge, reopening the world to interstellar travel.
The next leg of their journey through the Space Bridge brought the Autobots to fabled Junkion, a world composed entirely of space junk. Sabotage brought down the Ark shortly after their arrival, and Optimus Prime tasked Perceptor with getting things up and running again. He also performed an exploratory check on Junkion's four Space Bridge nexii, and determined that one was indeed still in working order. (The one indicated by the Matrix, but of course Perceptor made his own observations first.) Perceptor's work proved valuable, and the Ark was able to regain flight even amidst the arrival of the Nemesis and the chaos created by the unearthed Requiem Blaster. After the battle over Junkion ended, Perceptor updated Optimus Prime on the status of the planet and the ships involved in the skirmish. The Ark then set a new course for the Allspark itself.
Perceptor reported to Optimus Prime on the Ark when the Matrix led them to Aquatron. He joined the main Autobot force when it touched down on the planet, making contact with the Curator and his Aquatronians. Perceptor was greatly intrigued by the parallel evolution seen on the planet compared to Cybertron, and was eager to perform tests on their ultra-refined energon supplies. The scientific curiosity overcame his caution-circuits though. The Curator was revealed as a Quintesson with a grudge millions of years old against the Cybertronians, and Perceptor was among the Autobots who were captured and forced to face trial on ridiculous trumped up charges. The Autobots and Decepticons escaped during the trial and met up with their comrades aboard the Ark and Nemesis to fend off the Sharkticon hordes and ultimately escape the planet.
As the Ark was readied for launch, Perceptor was put in charge of the task of shutting down Autobot City in preparation. Unfortunately Grimlock abandoned his post, allowing the Decepticons to attack through the unguarded sector, and leaving Perceptor with the problem of powering the city back up again to reactivate the defenses. To make things worse, he and his team in the nerve center were under siege from the Decepticon forces. After Optimus Prime and Warpath came to their aid, Perceptor and Optimus decided to try using some of the energon from the Ark to report the defenses, so while Perceptor coordinated from the nerve center, Optimus set about rerouting the energon flows. Working together, they were able to get some guns online, but exhausted the available energon. A short time later Optimus managed to awaken Metroplex to chase off the rest of the Decepticons though, and Perceptor was later aboard the Ark as it launched. His status is left unknown.
Following the restoration of Cybertron from the Great War, Perceptor was one of the many Autobots blacklisted by the new High Council for being a supporter of Optimus Prime.