Since 
the middle of the 1980s Transman has been engaged in handling post. At sorting 
centres material handling is a major part of the operations and a part well suited 
for gantry robot solutions. 
Transman robots are primarily used for handling letters after they have been 
  sorted into plastic trays by letter sorting machines. The plastic trays are 
  labelled with bar codes that contain information about the addresses of the 
  post in each tray. With the aid of the bar codes the Transman robots then sort 
  the trays and stack them in special carriages. These carriages are then loaded 
  manually onto trains or lorries for further transportation to the sorting centres 
  nearest to the addresses in question. 
  At these sorting centres the trays are quite often resorted so that each carriage 
  can be refilled with even more precisely sorted post. 
  A gantry robot is used when the trolleys are unloaded for resorting and the 
  final loading of the carriage is also carried out using a similar type of robot.