About the size of a radio-controlled car, Lancelot and competing robots are completely autonomous, with on-board computer "brains" directing their movements.
(About the size of a radio-controlled car, Lancelot and competing robots; are; completely autonomous) (on-board computer "brains; directing; their movements)
About the size of a radio-controlled car, Lancelot and competing robots on-board computer "brains
are directing
completely autonomous
their movements