Crawler Tractors PR 714 PR 764 Product information Grade control systems
Grade Control Systems for Crawler Tractors To be successful in spite of ever-increasing time and cost pressures, construction machinery must meet the most demanding requirements when it comes to operating speed and accuracy. For this reason, automatic machine control systems are being used increasingly to improve the productivity of the operator and machine. These systems use digital planning data to control the machine s attachments automatically when removing or depositing material. With the aid of the latest technology, complex surfaces and exact grades can be produced quickly and precisely. Thanks to their innovative travel drive, Liebherr crawler tractors are ideally suited to use automatic controls. The hydrostatic drive provides uninterrupted power without any gearshifting. Due to the long tracks and the perfect match of front attachment, working hydraulics, and base machine, best grading properties are ensured. The machine s low centre of gravity makes it possible to work safely even on steep embankments and highly inclined grades. The benefits of automatic machine controls: Reduced use of stakes and string lines and thus reduced personnel costs. No lost time from control measurements and costly follow-up work. Fewer passes, less wear and lower fuel consumption. Economical use of materials through precise material deposition. Increased machine efficiency and faster project completion. Depending on the application, different control technologies are used. To make installation easy, Liebherr offers a number of preparation kits. They ensure that subsequent installation of the grade control system on the crawler does not require accessing the inside of the machine. 2 Product information - Machine controls
2-D Laser Control Applications Creation of horizontal or inclined surfaces with high accuracy. Suitable for small to medium-sized construction sites. Use in the construction of sports fields, roads, construction of car parks and industrial plants, housing pads, etc. Components In the field On the blade In the cab Rotating laser 1 or 2 laser receivers Optional: Cross slope sensor Control unit Pictures above show Topcon components. Operation The rotary laser rotates at a high speed, generating a reference surface with the laser beam. This surface is horizontal or inclined, but always flat (two-dimensional). The laser receivers are mounted on masts attached to the blade of the crawler tractor. They catch the emitted laser beam and thereby determine the current lift of the dozer blade in relation to the reference height. For applications with less demanding accuracy requirements, a single laser receiver that determines only the height of the blade suffices (Single Laser). The control unit with its integrated display is located in the cab within easy view and reach of the operator. It processes the signals from the laser receivers and cross slope sensor, and constantly regulates the lift and tilt of the blade via the working hydraulics. When working in automatic mode, the operator needs only to steer the crawler, while the machine controls operate the blade automatically. This creates a surface parallel to the laser-generated plane. Normally, however, 2 masts or one mast and a slope sensor are mounted. This allows both the height and the tilt of the blade to be determined (Dual Mode). Worth Knowing There must be visual contact between the rotating laser and the crawler tractor. A simple and relatively inexpensive system, but not suitable for creating 3-D contours. With a single rotating laser, several machines can operate on the same grading level. Product information - Machine controls 3
3-D GPS/GNSS Control Applications Creation of large grades and complex, three-dimensional design surfaces. Suitable for medium-sized to very large construction sites. Use in road and railway construction, golf course construction, commercial and residential site preparation, in earthmoving and landfill applications, etc. Components In the field On the blade On the machine In the cab Base station 1 or 2 GPS antennas Optional: Cross slope sensor Pictures above show Trimble components. Data-transmitting radio Control unit Operation The mast-mounted GPS antennas on the blade receive signals from several GPS or GLONASS 1) satellites and in this way establish the position of the blade. A base station is needed to achieve the required accuracy. Its position is measured and calibrated accurately when setting up the construction site; it radioes correction signals to the machine continuously. Companies are also starting to rely increasingly on correction data that can be retrieved via GSM from regional providers. It is possible to work with one or two GNSS antennas. When working in dual mode, the alignment of the blade is also taken into consideration. This eliminates deviations that can arise when angling a 6-way blade. The surveying data for the desired terrain profile are transferred to the control unit and displayed to the operator graphically. The control unit processes the signals from the GPS receivers, slope sensor and base station, and compares them with the target data stored. It then automatically regulates the lift and tilt of the blade by means of the hydraulics. This creates a profile that corresponds to the terrain data specified. In certain cases, GNSS systems are combined with laser sensors to achieve increased elevation accuracy. 1) Satellite-aided control systems are usually called GNSS (Global Navigation Satellite System) systems today, since they access not only GPS, but also other positioning systems such as GLONASS. Worth Knowing There must be visual contact between the GNSS satellites and the machine. Not suitable for work underground, in narrow valleys or in forests. Visual contact between machine and base station is not required. One base station can serve any number of machines on the construction site (radio connection). 4 Product information - Machine controls
3-D Control with Total Station Applications Creation of large grades and complex, three-dimensional surfaces with high accuracy. Suitable for small to medium-sized construction sites. Use in road and railway construction, golf course construction, site preparation for residential buildings or industrial plants, fine grading of runways for airports, etc. Components In the field On the blade On the machine In the cab Total station Receiver prism Cross slope sensor Data-transmitting radio Control unit Pictures above show Leica components. Operation The total station detects and follows the receiver, which is mounted on a mast attached to the blade. The distance to the receiver as well as the horizontal and vertical angles are determined continuously. Prior to commencement of work, the total station is calibrated so that its position is known accurately. The exact position and elevation of the blade can be constantly determined and the working hydraulics are actuated accordingly. Only one mast is used; accordingly, a cross slope sensor is always required to detect the tilt angle of the blade. As with GPS, the terrain data are stored in digital form in the control unit. It processes the 3-D position data from the total station and the measured cross slope, compares them with the stored target values and controls the blade continuously to achieve the desired terrain profile. Worth Knowing There must be visual contact between the machine and total station. If this contact is interrupted briefly, the station initiates a correction automatically, or the operator actuates a new target search once the obstacle is no longer present. One total station per construction machine is required. Use for creating 3-D surfaces with high accuracy, or where GPS reception is not possible. Product information - Machine controls 5
Site Management Site management systems are being used increasingly for construction projects. Among other things, these systems permit direct communication between the construction machines, and surveyors and planning offices. This allows changes in the planning data to be transmitted directly to the crawler tractor, or progress reports to be transmitted from the machine to the site management office. Exact monitoring of the progress of the project and online storage of relevant site information are also possible. Often, remote maintenance of the control system via direct online access to the control unit is possible. The aim is to increase the efficiency of project processes further and improve utilization of the construction equipment deployed through a faster means of communication. Preparation Kits for Liebherr Crawlers Which control system on which machine? Generally, 2-D and 3-D machine control systems of all common manufacturers can be installed on Liebherr crawler tractors of any size. In practice, when working with automatic machine control systems, small to medium-sized crawler tractors are used for the most part. Preparation Kits for Liebherr Crawler Tractors Liebherr offers factory-installed preparation kits for grade control systems of various manufacturers. These include all preparations on the machine that are necessary for subsequent installation of automatic controls. This means electrical and hydraulic installations as well as mounting brackets and plug-in connections. With a factory-install preparation kit, installation of machine controls in the field is simplified considerably. The individual system components such as masts, slope sensor, display and control unit, GPS antennas, receiver prism or data-transmitting radio can be installed easily or simply plugged in. Since these kits support all of the below-listed systems from a given manufacturer, subsequent upgrading of a crawler vehicle e.g. from 2-D to 3-D it is possible at any time. 6 Product information - Machine controls
Compatible Control Systems TRIMBLE preparation TOPCON preparation LEICA preparation 2D-Laser Control: GCS900 3D-GNSS/GPS-Control System: GCS900 with Single GPS or Dual GPS 3D-Control with Total Station: GCS900 with Tachymeter ATS/UTS 2D-Laser Control: 9164 System V 3D-GPS Control System: 9169 Z63 GPS/GLONASS, mmgps, 3D-MC 2 3D-Control with Total Station: 9169 Z63-LPS 2D-Laser Control: Leica icon grade 32 3D-GPS-Control System: Leica icon grade 42 3D-Control with Total Station: Leica icon grade 42 Availability of the preparation kits for different crawler tractor models must be clarified with the local Liebherr dealer. If you wish to install an existing, older control system on a new machine with a preparation kit, we recommend that you contact the respective control system manufacturer. Components Included in the Preparation Kits Complete wiring inside the machine, including plug-in connections and power supply. Brackets for mounting the masts as well as holder for the cross slope sensor. Module for remote data transmission (not included in all kits). Connecting cable and mounting provisions on the cab for data-transmitting radio/antenna, for operation with GPS/GNSS or a total station. Symbol photos. The component versions vary with the different kits. Hydraulic valves and hydraulic hoses inside the crawler vehicle. Mounting base and connections for the control unit in the cab. For ease of operation, the automatic-mode switch is usually integrated into the joystick. (The monitor shown is not included in the kit). Product information - Machine controls 7
The Liebherr Group of Companies Wide Product Range The Liebherr Group is one of the largest construction equipment manufacturers in the world. Liebherr s high value products and services enjoy a high reputation in many other fields. The wide range includes domestic appliances, aerospace and transportation systems, machine tools and maritime cranes. Exceptional Customer Benefit Every product line provides a complete range of models in many different versions. With both their technical excel lence and acknowledged quality, Liebherr products offer a maximum of customer benefits in practical application. State-of-the-art Technology To provide consistent, top quality products, Liebherr attaches great importance to each product area, its components and core technologies. Important modules and components are developed and manufactured in house, for instance the entire drive and control techno logy for construction equipment. Worldwide and Independent Hans Liebherr founded the Liebherr family company in 1949. Since that time, the enterprise has steadily grown to a group of more than 130 companies with over 38,000 employees located on all continents. The corporate headquarters of the Group is Liebherr International AG in Bulle, Switzerland. The Liebherr family is the sole owner of the company. www.liebherr.com Printed in Germany by Typodruck BK LWT / VM 11601157-0.5-04.13_enGB Subject to technical modifications. Liebherr-Werk Telfs GmbH Hans Liebherr-Straße 35, A-6410 Telfs +43 50809 6-100, Fax +43 50809 6-7772 www.liebherr.com, E-Mail: lwt.marketing@liebherr.com www.facebook.com / LiebherrConstruction