Bogie under Ariane 6 mobile gantry

The mobile gantry, a 90 metre-high 8200 tonne metallic structure stands on 16 bogies. It houses Ariane 6 until it is retracted about five hours before the launch. 

Each bogie comprises eight wheels and each wheel is equipped with one electric motor. A total of 128 automated electric motors synchronise to set the wheels in motion so that the mobile gantry can retract 141 m along rails away from the launch pad in the final countdown to liftoff.