Reach the center of the complex was a mission in The Precursor Legacy that Jak and Daxter completed to obtain a power cell. A power cell is collected after Jak traverses a dark eco pool with many precursor platforms.
Done right after the mission "Follow the colored pipes", you will enter a room filled with a dark eco pool and a power cell on a platform in the middle with two rotating rings made up of single platforms surrounding it. The platforms around the cell will flip forward every so often (they'll shake when they do) causing you to fall into the dark eco below if you were standing on it.
It is possible to just roll-jump straight at the power cell, otherwise you can either go as fast as possible but just make sure to avoid jumping on a platform that is shaking, indicating it will flip over.