Industrial overhead-crane synchronization & automation

The over-head crane has 2 arms, which are to be synchronized for filling hot liquid aluminium in the furnace.
The assembly involves 2 incremental shaft encoders, which are coupled with the DC motors. The position of individual crane is as per the setting done on the controller. Each arm is first positioned as per the sequence. The vessel containing the hot liquids are tilted to be filled in the furnace.