Liebherr PR 724 Litronic - Manual (Page 4)

PI_PR724-764_enUS.INDD 4 18.12.2009 13:24:26 Uhr
GPS control
Applications
Establishment of large grades and complex, three-dimensional surfaces •
Suitable for medium sized to very large construction sites •
Application in road and rail construction, construction of golf courses, industrial facilities, earth moving, landfi lls, •
etc.
Components
How it works
The mast-mounted GPS antennas on the blade receive signals from several GPS satellites and thereby establish the
position of the blade. The base station is needed to achieve the required accuracy. Its position is measured exactly
prior to commencement of work; it continuously sends adjustment signals to the machine via radio.
Also with the GPS, operation with one or two masts is possible. In two-mast operation, the elevation and the tilt of the
blade as well as its orientation is determined - minimizing grade deviations caused by angling the 6-way blade.
The survey data of the desired terrain profi le is available at the jobsite in standardized formats. They are transferred to
the memory card of the control unit and shown to the operator graphically on the display.
The operator can select between various views and therefore knows exactly where the machine is at this point in his
working range.
The control unit processes the signals from the GPS receivers, slope sensors and base station and compares them with
the stored specifi cation values. The elevation and tilt of the blade is automatically regulated via the working hydraulics
- creating a profi le that corresponds to the specifi ed terrain data.
Useful information
Visual contact between machine and the GPS satellites must be present. Not suitable for work underground, in •
narrow valleys or in forests
No visual contact between machine and base station is required
•
A base station can control any number of machines on the jobsite (radio connection) •
Height accuracy < 3 cm •
In terrain On the dozer blade In the cab
Base station 1 or 2 GPS antennas Option:
Cross slope sensor Control unit
Symbol images only
4 Grade control systems
PI_PR724-764_enUS.INDD 4 PI_PR724-764_enUS.INDD 4 18.12.2009 13:06:56 Uhr 18.12.2009 13:06:56 Uhr