- SPECIAL REPORTS
- THE MAGAZINE
While working with several new startup firms recently, I noticed they were purchasing fairly high-end surveying equipment.
These systems include combinations of robotic total stations and GNSS units. I spoke with representatives from Leica Geosystems, Earth Vector Systems and Geoshack to get their views on how firms are using this equipment.
All these representatives say this equipment is improving productivity in the industry. But although interest in purchasing these systems seems to be picking up for the first time in years, it may be occurring in lieu of hiring new employees.
“I generally see the economy improving as a result of increased interest in technologies and request for quotes and corresponding purchases,” says Greg Perkins, a technical sales and support specialist with Leica Geosystems. “Organizations seem to be more interested in acquiring technologies now than they are in adding staff. The feeling seems to be that technology allows surveyors to do more with fewer people.”
Perkins says customers are finding new ways to use two Leica systems--the Viva GNSS and the GS09 GNSS. These pieces of equipment are for simple boundary and topographic surveys, as well as high-end, high-accuracy construction projects. The Viva is sold either as a completely integrated system or in modules. This high-end solution offers static, rapid static and kinematic data capture along with the reliability, convenience and accuracies that total stations provide. The system debuted in September 2009 and supports GPS and GLONASS and is designed for the upcoming Compass and Galileo systems from China and Europe, respectively. It works directly with the robotic systems.
The Leica GS09 GNSS system offers a complete real-time surveying system with a midrange pricing structure. The RTK base station requires the GS09 SmartAntenna, a radio and battery. The rover works on all reference networks, and it can receive network corrections with the Leica GSM/CDMA modules or by cell phone. The total station components can combine with the SmartAntenna to create a single instrument.
The Washington Metropolitan Area Transit Authority uses this equipment to compute 3D as-built rail data and clearances. The clearance measurements are then uploaded to rail tamping cars, which correct movements in the track.
The Leica equipment is also contributing to the work on the underground people-movers at Dulles International Airport and the Dulles Metrorail extension. This 23-mile rail line is a $4 billion project consisting of at-grade, above-grade and below-grade rail lines and terminals. The tunnels for the people-movers are constantly monitored to ensure that no movement occurs during construction.
Trimble dealer Bill Moore, LS, the owner of Earth Vector Systems LLC in Charlottesville, Va., says he is noticing that surveyors are beginning to understand the value that GIS brings to projects and clients. The available collection systems include software that can gather GIS attribute data while collecting coordinate and raw data.
Moore says one of the strong points of the equipment is that in many cases users can purchase just the technology needed and add it to their existing hardware. The equipment also comes in a variety of price points and feature points. “Many surveyors don’t have the confidence that the economy is picking up for the long term and are still cautious in their investments,” he says.
Moore says a shift is occurring in how companies use equipment. In the past, customers would sometimes acquire the technology and then find ways to use it. Now, he is seeing surveyors get projects first and then figure out how they can automate them.
Trimble offers the S3 Total Station and the R4 GPS/GNSS unit, and users can combine the S3 with Trimble’s GNSS receivers to create a Trimble I.S. Rover for integrated surveying. The instruments seamlessly integrate GNSS receivers/GPS receivers and optical total stations.
Instead of offering a combined piece of equipment, Trimble believes a total station (TS) should work at the same time the GPS unit is working, thereby obtaining a double effort of data collection.
However, Moore says Trimble does believe the data collector should receive data from either device at an instant’s notice. Both the TS and GPS are affordable and preserve a high quality of data and performance.
Trimble ties these two collectors together with Trimble Access; its purpose is to deal with data transfers. Through a wireless connection, it can provide or receive data. This allows remote access to the office, which can also help with troubleshooting. This supports Trimble’s concept of the “Connected Site.”
Trimble Access is 18 months old and sits on the handheld Trimble TSC2 Controller. It is a data handler that is sensitive to which device is working and is used for general surveying, road stakeout and collection, tunnels and other assorted projects. It also includes sync, settings, forecast and GNSS capabilities and uses Windows Mobile 6 and an Internet setup that benefits from all of Microsoft’s utilities. “The equipment on the market is tried, true and stable. Now, it is all about software,” Moore says. Trimble also offers the VX, which is a Trimble S6 with point cloud scanning. Although it is a little slower than the GX or FX (high-end scanners), it works well for integrated surveying.
Moore says a surveyor with Access can locate some of the project’s control points and establish a backsight with the TS and then switch to a GPS unit for observed real-time data. When encountering overhang areas, trees and other non-GPS-friendly circumstances, the surveyor can switch back to the TS. The resulting reports show which data were collected by which device.
Chris Nelms, a survey specialist for Topcon dealer Geoshack in Texas, echoes Moore’s claim that surveyors need to be more proactive in seeking projects that supply data to GIS systems. He says many counties and municipalities are earnestly seeking this data now. He recommends the Topcon GRS-1 (Geodetic Rover System) to obtain survey grade RTK data from reference networks or submeter accuracy from WAAS. It is a dual-frequency, 72-channel GPS + GLONASS receiver.
The Topcon unit captures photographs and attaches them to 3D points. Nelms says surveyors can go into the field and capture what they need. If later on, they realize other information is needed regarding a point, the photos may have captured the necessary data. Because 3D points are linked to the photo, the surveyor may be able to avoid an expensive trip back to the site.
TopSurv serves as the data collection software for Topcon’s systems. He says some manufacturers now support CAD, ESRI and MicroStation export formats.
One area Nelms says is picking up for him is police departments needing the equipment for forensic capabilities. Police use the Topcon IS robotic system for data collection of accident sites and for taking pictures to augment the digital data. The Imaging Station (IS) ties the points into the photo. This allows the police to get traffic moving more quickly after an accident than if they had to manually survey the site. With this combination of total station and built-in camera solution, some surveyors are finding they don’t require a massive point cloud. It also runs about half the price of the scanner.
Topcon and Sokkia Base/Rover GPS systems can come with GSM or CDMA cell radios so both receivers can be used on an RTK network when not in use together as a base and rover. The Topcon GRS-1 is designed as an RTK network tool, although it can be used with an RTK base radio, WAAS or Coast Guard Beacon in GIS mode. The Sokkia GRX-1 receivers have built-in radios for conventional RTK GPS and internal GSM for an RTK network. The receivers can be used interchangeably as a base station, rover or two rovers on an RTK network.
Nelms says an advantage of the TopSurv software is its ability to perform corrections as the surveyor moves from one piece of equipment to another, say from a TS to GPS. TopSurv adjusts the scale factor, allowing the surveyor to move back and forth easily.
An adjunct product called RTK Bridge by Intuicom allows users to automate older equipment, get it on the network and avoid retraining, Nelms says. This has a high-powered industrial cell phone built in with a greater range than a traditional cell phone. This solution supports NTRIP and all standard correction formats, provides extension to CDMA/GSM networks, replaces the need for RTK base stations and supports legacy radio systems.
Editor's note: This article is not intended to be a comprehensive overview of all total station/GNSS technologies. For additional information on GNSS systems, including new product announcements, visit www.pobonline.com.
1. http://www.intuicom.com/www/ products/rtkBridge.htm
Sidebar: New and on the HorizonIt should be noted that Carlson Software is continuing its move into the hardware field. The Carlson Surveyor+ GPS debuted in July. It is a dual-frequency RTK GNSS receiver and controller, supporting network RTK, and base and rover RTK, and it is static capable, as well. This unit is a scalable piece of technology, allowing users to buy the Surveyor+ and add the GPS later. The system comes with the popular SurvCE product built-in. This system also offers the ability to switch between TS and GPS and performs survey computations on the collector.
Surveyors have one other thing to look forward to in the not-so-distant future: the broadcast of L5 signals. Perkins of Leica says the signals will bring some amazing new capabilities. “When this technology appears, we will have better satellite access that will increase real-time survey grade computations from GPS units,” he says. “Further, the spacing of GPS reference stations will be able to be spaced farther apart than is currently feasible. This will increase coverage areas with higher accuracies and all at less cost.”
Perkins says the L5 signals are expected in 2013.