The present invention relates to a
mobile station of
Global Position System (GPS) for a rubber-tiered
gantry crane (RTG), and it mainly comprises one or two
GPS receiver(s), a
radio receiver, two crane encoders, a control processor, and a
programmable logic controller (PLC). The
mobile station adopts Real Time
Kinematics (RTK) technology of the GPS, and gets a high precision coordinates of three dimensions, then sends it to the control processor and gets the current crane position of the RTG and the offset between crane wheel and the
central line of crane
runway. At the same time, the control processor receives and calculates the signals sent by the crane wheel encoders, and checks up and reckons the crane position and the crane wheel offset, converts it to a 4-20 mA current
signal by a digital-analog converter (D / A) or transfers it to the PLC directly by a
serial port, and complete the crane auto-steering function; on the other hand, the control processor calculates the crane position and transfers it to the PLC via the
serial port, completes the auto-register of the container management. The present invention can make the RTG keep agility with in moving from one
yard to another, and can also make it work stable and reliably like a rail
gantry crane and report the accurate container positions. Thus, the container management is made to be highly automotive.