The Technology Benchmark: Instrumental systems for the future.
by Harry O. Ward, PE
August 2, 2010
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.”
 |
| The
Leica Viva GNSS offers static, rapid static and
kinematic data capture
along with the reliability,
convenience and accuracies that total stations provide. |
|
On
Track with Leica
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.
 |
| Users
can combine the Trimble S3 Total Station with Trimble’s GNSS receivers to
create a Trimble I.S. Rover for integrated surveying. |
|
One
interesting way that Perkins says this equipment is being used is for the
Amberg rail solution, an increasingly popular solution in the United States
for rail design and maintenance. The Amberg solution is a rail-specialized
scanner of sorts that is highly controlled by alignments and profiles. It
produces a circular point cloud cross section of data. These sections are then
used to check clearances between the railcar and surrounding features,
including tunnel walls and rail heads. It can then compute where the rail head
is and compare it to where it should be.
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.
 |
| The
Topcon
GRS-1 captures photographs and attaches them to 3D points.
ted surveying. |
|
Staying
Connected with Trimble
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.
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| Sokkia
GRX-1 receivers function interchangeably as a base station, rover or two rovers
on an RTK network. |
|
Getting
to the
Point with Topcon
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.
Reference
1. http://www.intuicom.com/www/
products/rtkBridge.htm
Sidebar: New and on the Horizon
It
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.
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