They could be Cybertronian exiles who became space pirates being pursued by the Autobot Elite Guard (or something), who deliberately take the form of robotic dinosaurs just to be mischievous when they arrive on Earth. They're not inherently bad, and eventually side with the Autobots to fight whoever the main villain is. At the end of the movie they escape to get away from the Elite Guard who plan to arrest them after the primary villain is neutralized. Grimlock, of course, is the captain. I imagine one of the humans being scared shitless (like Sam was by Ironhide) only much worse by Grimlock. Then Grimlock proceeds to tease him with his fiery sword until -get this- Ironhide tells him to cut it out.
With the way michael bay and his writers are im sure an explanation like that would be perfect LOL Or maybe they will do like they did in ROTF and they will just appear out of no where with no explanation at all...............i think that sounds more orci bay like
They could make it either like Animated, where they Allspark creates them and they gain sentience later, or they could make it like G1 where they are built by the Autobots.
The G1 idea is the least realistic. I'd expect the Autobots to be smarter than to make dinosaur robots who look very obvious in both modes. The Animated idea seems to bland to me. I think making them space pirates is more interesting, and brings a new level to them.
I think I read a fan script alooooooong time ago where the Dinobots were basically the Autobot swat team. They answered Optimus's signal and headed to Earth, crash landing right in the middle of a battle with several decepticons. Still in their weak comet/protoforms they searched for the most powerful forms they could find, dinosaur exhibits. So its not like they choose to be Dinosaurs, it was just the best things they could find while under fire.
Well I like the idea that they're mischievous brutes. The alt mode doesn't matter, because the Cybertronian is going to be stronger than it no matter what.
Well, if the writers and Bay actually thought of the Cybertronians as actual characters then the question does indeed come up "What has everyone else been doing all this time since the Allspark was lost?". Obviously many would be looking for it, some would be fighting the war, and others would likely go "Screw this, I'm doing my own thing.". Considering they can travel from system to system under their own power, space-piracy doesn't sound like a bad gig. I can also see the Dinobots being terribly contrarian about "hiding". Megatron apparently never bothers, so why should they? They crash down, scan some huge and powerful animals (remember how freaking big the species they become are) from a museum or exhibit and basically tell Prime to slag off when he points out they aren't really disguises. We've still never reached any consensus about "Dinobot speak" versus the more articulate dialogue we get in some comics. - Coeloptera
I think the most logical explanation for Dinobots would be the following: Autobots that crash-landed on Earth long time ago. Scan dinosaurs (for whatever reason. Does it really matter?) Something happens to them in that era; meteor strike, ice age, whatever. They sustain major damage. Go into stasis lock. Flash forward to modern day. Archeologists stumble upon "fossiles". Autobots rush to the scene, bring them back online, and due to the damage they received, their processors are kind of effed up. Therefore lack of intelligence and Grimlock's referring to himself in the third person. If we can have giant robotic scorpians in the movieverse, its not TOO far-fetched to incorporate Dinobots.
Scorponok can technically be hidden when he joins Blackout's alt mode. So his scorpion mode serves as his "I am not hiding"-mode; whereas the dinosaur modes of the Dinobots, theoretically would serve as a "I am hiding"-mode according to your idea. So the reason I proposed my idea is because it explains that they deliberately turned into robotic dinosaurs to be spiteful and mischievous. These dinosaur alt modes would not look like bones, nor fleshy animals - they would look robotic and completely useless for hiding.
More like "I WAS hiding when my alt mode was scanned and still relevant." I like your idea as well. It really doesn't matter to me what their origin is. I just want cybernetic rebellious dinosaur autobots. "Tank Grimlock" FTL.