Global Positioning Systems

Leica Viva GS-15 GNSS GPS Receivers with CS-15 Data Loggers

With support from the NSF CI-TRAIN Initiative, CAST has acquired three Leica Viva GS15 receivers and two CS15 controllers. These GPS units collect survey grade data in a number of environments and are often used in construction, geology, and archaeology, as well as other fields. The GS15s are multi-capacity GNSS (global navigation satellite system) capable units that can simultaneously track the US NAVSTAR, Russian GLONASS and European GALILEO satellites. The units are also capable of acquiring the next generation L5 frequency.

The CS15s are comprehensive data loggers and are used to configure the GS15 receivers.

Trimble 5600 Robotic Total Station DR200+

The Trimble 5600 DR 200+ is a robotic total station that provides a long range surveying capabilities. This instrument is capable of 2" angular precision and, in reflectorless mode can measure distances up to 600m with an accuracy of 3mm +/- 2ppm. With the active prism, the EDM can measure distances up to 5,500 meters with an accuracy of 2mm +/- 2ppm. Used for control point placement, site stake-out, micro-topography surveys and more, the 5600 provides a flexible solution to many geomatics applications.

The instrument may be linked via an integrated UHF radio to the powered prism pole so that, as the pole moves from point to point, servo motors swivel the total station's telescope in both horizontal and vertical angles to stay aligned with the active prism. Because the data logger is attached to the prism pole, the operator can control all aspects of the instrument remotely: one person surveys, even high resolution micro-topography, are feasible and have been demonstrated many times by researchers at CAST. Both angle and distance measurements are easily integrated with GPS data collected from the Trimble 5700/5800 in a least-squares network adjustment using Trimble's Geomatics Office software.

Trimble 5700/5800 GPS Receivers

For large-site survey applications requiring extremely accurate horizontal and vertical measurements, the Center operates one Trimble 5800 Receiver/Antenna combination, one Trimble 5700 with a Zephyr antenna, and one 5700 Trimble 5700 with a Zephyr Geodetic antenna. This combination of geodetic grade GPS equipment is configured to operate in static, fast-static, and real-time kinematic (RTK) modes. In static and fast-static modes, all three receivers can be integrated in a classic trilateration network configuration or simply act to measure base-lines between two receivers at a time. In RTK mode, the 5800 and 5700/Zephyr operate as rovers linked with the 5700/Zephyr Geodetic base station.

In addition, all three receiver/antenna combinations can be configured with data modems to communicate with an established NetRS base station operating from the top of the University of Arkansas Science and Engineering Building. The NetRS receiver is owned by DCI Engineering of Little Rock, AR and jointly operated with CAST. Real-time network solutions using the NetRS are available for research activities in and around Northwest Arkansas and archived observations are available via ftp. All of these GPS observations can be easily integrated with traditional EDM and angle measurements from the Trimble 5600 Robotic Total Station in a least-squares adjustment using the Trimble's Geomatics Office.

Trimble GeoExplorer

For high-precision mapping, CAST has three Trimble GeoXH Handheld receivers, which deliver sub-foot (30 cm) GPS accuracy. For more general mapping applications, CAST has five Trimble GeoXM Handheld receivers, which deliver 1- to 3-meter accuracy. Both these units provide 8-hour battery life.

CAST also has two Trimble GPS Pathfinder Pro XRS receivers, which can deliver real-time beacon-corrected sub-meter accuracy.

Trimble Juno™ ST Handheld GPS Receiver

The Juno ST/SB handheld is a highly productive yet affordable, non-rugged GPS receiver for field data collection and mobile GIS. The Juno ST/SB handheld is Trimble's most compact, lightweight, fully-integrated field computer, providing 2 to 5 meter GPS positioning in real time or after post-processing. CAST currently has 16 of these units available.

Incorporating a high-sensitivity GPS receiver, it has been specifically designed to maximize yield of positions in hostile environments, such as under forest canopy and up against buildings. The integrated WAAS receiver can be used in the field for real-time field corrections of 2 to 5 meters. Or you can collect data in the field and postprocess it back in the office to ensure positions are defined to the required accuracy level for your GIS, and to control the overall quality and consistency of your data.