The Face Alignment UC describes the automated process for straightening the conveyor line respective to an aerial view.
The Face Alignment System cyclically reads the Shearer’s position for determining the completion of a full shear. If a full shear was detected, the Face Alignment System uses its measurements to calculate offset values for each shield. After the calculation is finished, the Face Alignment System increases its SequenceNumber.
The Roof Support System cyclically reads the SequenceNumber of the Face Alignment System. If a new SequenceNumber was detected, the Roof Support System reads the new calculated offsets from the Face Alignment System and applies these offsets for the next shear. Figure 7 contains the sequence diagram of this UC.
Figure 7 – Sequence diagram of the Face Alignment Use Case