A manufacturing cell for inspecting workpieces such as magnetic disk
substrates comprises an input conveyor for providing workpieces to be
tested, one or more testers for inspecting the workpieces, and three or
more output receptacles for receiving tested workpieces. One or more
robotic arms move the workpieces from the input conveyor to the tester
and from the tester to one of the output receptacles depending upon the
results of the test performed by the tester. The output receptacles
include a pass receptacle, a reject receptacle, and at least an
additional receptacle for workpieces that are to be re-worked or studied
further. If the additional receptacle is full, workpieces that would
otherwise be provided to the additional bin are placed in the reject
receptacle. The reject receptacle is very large, so that it is rarely
filled to capacity.