The relationship between surveying and geographic information systems (GIS) is integral for the development of most spatial data applications. Accuracy and precision in measurement matter. While the numbers and types of surveying related tools for measurment has grown, they in turn must interoperate with GIS, empowering applications to deliver results. ASM editor Jeff Thurston interviewed Brent Jones – Surveying and Engineering Industry Manager, Esri to discuss the relationship of surveying to GIS, and to learn more about how Esri is meeting the challenge to support and empower surveyors with GIS tools.
ASM Magazine: Could you briefly describe the connection of surveying to geographic information systems (GIS)? Why does it matter?
BJ: The term ‘surveying’ or ‘surveyor’ has different meanings, particularly how it is defined around the world. The International Federation of Surveyors (FIG) defines a surveyor as a professional person with the academic qualifications and technical expertise to conduct one, or more, of the following activities; to determine, measure and represent land, three-dimensional objects, point-fields and trajectories; to assemble and interpret land and geographically related information, to use that information for the planning and efficient administration of the land, the sea and any structures thereon; and, to conduct research into the above practices and to develop them.
With this definition, there are many connections between surveying and GIS and the connections are growing. GIS is a very effective tool for spatial information – the heart of surveying. With the tools in the surveyor’s tool box rapidly expanding – Lidar, laser scanning, mobile mapping – all collect massive amounts of data and GIS has essentially been established as the platform for managing all of that data.
Surveyors are key players in GIS. Their work in collecting and managing very precise data sets are the backbone of the authoritative data in GIS. GIS is relied on by many governmental and business for critical functions and spatial accuracy that can be delivered by surveyors.
ASM Magazine: Survey equipment manufacturers are continually innovating and developing new products. At the same time, your company develops improved GIS software. How do you keep all these products working together to support a surveying-GIS technology connection?
BJ: We have dedicated teams focused on rapid growth areas, such as imagery and lidar. We also work closely with our business partners giving them access to the newest available technology so they can improve, expand, and keep their solutions current and relevant.
A real key area here is our use of open standards. This facilitates rapid development and interoperability with many systems. When we all adhere to open standards, integrating data from new sensors and connecting to new devices is much simpler and more efficient.
ASM Magazine: What products does Esri produce that meet the needs of the surveying and engineering communities specifically? Can you describe a few examples where they are being used, particularly in Asia?
BJ: One new product that we are all very excited about is the Parcel Fabric. Actually, it’s not a product but new capabilities in ArcGIS to efficiently manage parcels. We had to develop a new data model that could manage behaviors specific to survey data and we built capabilities on this new model. We now can take survey data from a wide variety of sources and build a ‘Parcel Fabric’, which delivers the best mathematical representation of parcels based on actual measurements using a least squares adjustment. As new surveys are input, they are used to incrementally improve the quality of the Parcel Fabric.
In Asia and other parts of the developing world, a cadastre can be implemented with the information available, and then use subsequent survey data to improve the spatial quality of the Parcel Fabric. In the developed world, the Parcel Fabric is key for maintaining and managing accurate information with intuitive, efficient tools.
Engineers have some of the same challenges as surveyors – managing geospatial data in an environment where it is easily accessible, centrally located, and useful for analysis. There are studies that show that engineers spend almost half of their time locating and validating data. GIS provides the data management and accessibility capabilities to eliminate a lot of this inefficiency. GIS gives engineers new capabilities to use lidar, imagery, and mobile mapping for their existing work, while also providing the capability to offer new services.
One tool that is quite useful to engineers and surveyors is ArcGIS for AutoCAD. This free plug-in gives engineers and surveyors the ability to be in the AutoCAD desktop environment and leverage data in ArcGIS Server. This is now implemented for map services and is in beta for feature services. ArcGIS Server gives access to data and tools across an organization and with ArcGIS for AutoCAD, AutoCAD users can access and use enterprise GIS data while working in their familiar environment.
ASM Magazine: Esri has presented the concept of GeoDesign. How and where does surveying fit into GeoDesign?
BJ: GeoDesign is an exciting new area with a lot of potential. GeoDesign can be thought of as providing a design framework and technology to leverage geographic information, resulting in designs that more closely align with natural systems. Many existing design environments require engineers to be fairly far into the design process before impacts are calculated. GeoDesign can help us understand more development implications and much earlier in the process.
Surveyors have always been part of the design environment and with GeoDesign, surveyors play a critical role in providing data that engineers rely on for accurate analysis and overall design. As surveyors use more GIS for managing the data they collect, the same data management environment will be used by engineers, streamlining the process and providing engineering-grade data that can lend itself to result in a more natural design.
ASM Magazine: Can you briefly explain the differences between surveying data for use in CAD as compared to GIS? My sense is that many more people push survey data to CAD systems, whereas the GIS side is relatively under-developed. Would that be a fair statement?
BJ: Survey data used in GIS is the same data used in CAD. Data originates from a GPS, total station, laser scanner, photogrammetric workstation, or some other type of survey-grade data collection tool.
Surveyors have traditionally taken data from their tools and input the data into CAD to do calculations and produce a plan. Most survey work traditionally has been project based. This is changing. Many organizations directly input field collected data into GIS. Note the ‘S’ in GIS is for System. For example, many utilities collect survey data in the field and directly input the data into GIS. Because the utility is interested in operating a ‘system’ that manages its assets, the use of CAD for a project is not necessary.
It is a fair statement to say that GIS is relatively under-developed for survey data. I think there is still some legacy thought about the accuracy of GIS data that is a holdover from when GIS was primarily used for natural resource management. It’s not about the technology; it’s about the quality of the data in the system. There is also a culture shift from managing data in a file or files to managing it in a database. We see the shift taking place, but obviously not as fast as we would like.
A new capability that is in ArcGIS 10 is the ability to connect GPS in the field directly to the office with ArcGIS for Mobile. This capability powers a more efficient workflow by communicating field data to the office via cellular or other connection. This capability works in ‘sometimes synchronized’ mode, which means if you want real-time connectivity you can have it, but if you don’t need it, ArcGIS for Mobile will store up work and synchronize it when needed. The same data transfer from the office to the field exists. This will revolutionize many field workflows eliminating efficiencies such as returning to the field by allowing QA/QC being done in the office before the field crew returns from the field.
ASM Magazine: We are seeing a rise in the use of 3D within the geospatial and geomatics areas. This must present challenges to surveyors and technologies alike in terms of capture, management, analysis and representation. Can you explain some of the challenges you are finding in this respect?
BJ: With data capture, it seems that technology in surveying from the 1970’s until the mid-1990’s progressed at a manageable rate, i.e., EDM, total station, GPS. With lidar, terrestrial scanning, high resolution imagery, and others, surveyors are challenged with learning new tools and how to address the new markets. It doesn’t help that traditional surveying businesses are suffering with the poor construction market and the new tools are very expensive.
3D presents the new wave of GIS capabilities, particularly for data management and analysis. In addition to surveyors charged with learning how to effectively use the new tools, they are using new data management and analysis environments. And now the cloud is presenting another dimension in GIS capabilities. It is all very exciting, but challenging nonetheless to keep up.
Esri’s recent acquisition of CityEngine is another area where we see 3D capabilities in both the GeoDesign environment and visualization. It’s pretty exciting to think about design with an immediate understanding of a development’s impact and what it is going to look like in its surrounding environment.
ASM Magazine: It seems that many people get bogged down into a surveying versus GIS frame of mind – something I do not quite understand since high quality survey data can often have many purposes outside of legal land surveys. Architecture measurement, precision farming, volumetric modeling, and 3D visualization are just a few examples. Can you explain the nature of high-quality survey data and its value?
BJ: When I first came to Esri, I spent a lot of time trying to understand and convey what ‘surveying’ is. It came down to reliability and trust of data. Surveyors put their name on their data and stand behind it, legally and financially. When someone contracts for high quality data, they probably have some pretty valuable decisions to make using the data. For many, having someone responsible for the data makes sense. When the risk is low and there are no legal implications from the data provided, say like in precision farming, accuracy is very important and adds tremendous value, but it’s not usually considered in the survey domain.
ASM Magazine: Recently I had the opportunity to listen to your colleagues in the rail and airport industry. I was struck by the wide ranges of data types and quality that those sectors need to include in their workflows. How does ArcGIS integrate rail, airport, and other industry data into survey data workflows?
BJ: I think we have learned that both GIS and high accuracy (GPS based) survey are integral parts of the effective management of many of our modern business systems. I would include in that list all transportation sectors, construction and infrastructure, public works. Increasingly, those same technologies are taking us inside buildings as well.
There are current regulatory initiatives in rail, such as Positive Train Control in the United States, and ERTMS in Europe, and aviation – Next Gen Air Traffic Control in the U.S. and SESAR in Europe that require the integration of high precision GPS and GIS for better control systems, and more efficient navigation. Knowing where our assets and obstructions are, with a high degree of precision, is crucial to modern navigation. Managing that same information in a GIS has become the standard practice in all of these various areas, as we come to rely evermore on technology for the effective operation of these systems.
At the same time, business concerns have also discovered a wide range of additional uses for these technologies. So, while the railways discovered the use of high-precision GPS for locating their wayside assets, they also discovered that GPS and GIS could be used in their maintenance activities. High precision herbicide spraying techniques which combine both technologies are just one example. Airports are now capturing all of their assets and internal spaces with a high degree of accuracy, and then using that data for facilities, lease management, maintenance and security management functions. From the business and workflow side, GIS and GPS are a necessary and integral part of more efficient and effective management practices.
ASM Magazine: Some of our readers outside the U.S. may not be aware of the LightSquared 4G broadband network debates. Can you explain what it all means for surveyors and how it relates to data quality?
BJ: LightSquared is a proposed wireless broadband network for the United States. It proposes to use frequencies that are adjacent to the L-band that GPS uses and will broadcast a signal over a billion times stronger that GPS receivers are designed to receive. Tests show that it essentially jams GPS, eliminating the ability to capture high precision GPS positions. This is a good example of competition for segments of the electromagnetic spectrum. Unfortunately, these issues will continue as the demand for wireless data and voice services expand.
ASM Magazine: What is the Esri World Topographic Map? What purpose does it serve? How can surveyors in Asia and other places participate in it?
BJ: The Esri World Topographic Map was developed from some of the best available sources to provide a uniform, useful data set of the world. I have to add that the cartography is great. In addition to the use of several commercial data sets, Esri developed the Community Maps program where Esri users can submit their community’s basemap for all to use.
Anyone can use the World Topographic Map. Surveyors can use this map to plan their work and overlay additional data that they have themselves. We recently overlaid the entire U.S. National Geodetic Survey data on the basemap and made it available for free on ArcGIS Online. Surveyors in Asia can participate in the Community Maps program as well.
Additionally, included in ArcGIS is an OpenStreetMap editor, so areas where OpenStreetMap available, ArcGIS provides some nice editing tools.
ASM Magazine: Since you began with Esri what have you seen that has changed and what in your mind still needs a little more work?
BJ: I’ve been here six years and have been fortunate to be around some very significant changes in technology. The biggest change is the ongoing increases of the capabilities of the technology and the users’ imagination on how to reap benefits. Just thumb through the Esri Map Book and it is astonishing on the creativity and capabilities of Esri’s users.
As we move into the next big wave, the cloud is going to change things more than we can imagine. The data services available online are growing incredibly fast and the capabilities of GIS is growing extremely fast to leverage these.
Adapting to this accelerated change will continue to be a challenge. It’s one thing to talk about lifelong learning, but it’s another to actually become a serious lifelong learner. I think this is an area we all need to work on.
ASM Magazine: Can you briefly explain the relationship of surveying to geodesy? How does that get expressed through GIS?
BJ: Geodesy is a specialized type of surveying that takes into account among other things, the rotation and shape of the earth, gravity, and crustal motion. There are models developed to handle these aspects of surveying and measurement such as control networks, datums, coordinate systems and projections. Some of the tools, such as coordinate systems and projections are managed in GIS.
We recently installed our own CORS (Continuously Operating Reference Station) GNSS base station on the Esri campus. We are also participating with the academic community on a data model for geodesy. There is a lot of information besides positioning that can be extracted from GPS observations such as distortions from the ionosphere and troposphere.
ASM Magazine: What is the role of surveying in spatial data infrastructures (SDI)?
BJ: The geodetic control infrastructure is the foundation of spatial data infrastructure. It plays a key part in all ‘downstream’ data activities. Surveying and surveyors tie it all together. Some of the problems we face with integrating disparate spatial data sets results from not being ‘tied’ to control. We use the term ‘georeferencing’ which means that data is tied to a specific spatial reference frame. When this reference frame is created from the geodetic network, data is essentially mathematically spatially connected. Although we think of data overlay, actually if done in a survey framework, we understand the relationships between data layers and can manage them accordingly.
This is the philosophy behind the Parcel Fabric. Parcels are managed in a measurement network that is connected to the geodetic network. If there are revisions or improvements in the geodetic network, parcels can be adjusted to the new control. For countries just beginning to build a national parcel network, this technology provides a new efficient workflow that leverages newer, higher quality data as it is available without the need for wholesale remapping. For data that is referenced to parcels, it too can be adjusted using the adjustment results (displacement vectors) from the parcel fabric. This essentially makes the parcel network a tertiary control network.
The value that a good geodetic network brings to the economy is well demonstrated in a report done for the U.S. National Geodetic Survey that shows that the National Spatial Reference System provides 2.4 billion U.S.D. to the national economy. In developing nations with little passive control, implementing active control (CORS Network) can provide very high returns on investment by lowering the cost of all surveying leveraging GNSS.
ASM Magazine: What is new in ArcGIS 10 for surveyors and engineering interested users?
BJ: As I mentioned, the Parcel Fabric and parcel editing tools is new and exciting for surveyors. Additionally, ArcGIS Online is a new capability that enables surveyors to share data among a group or share with the public.
ArcGIS for AutoCAD permits organizations to centrally manage data while giving CAD users access. This capability eliminates duplicated data and gives the entire organization access to the same data.
ASM Magazine: Many cities and urban areas around the world are in need of infrastructure improvements. A question many of them ask is, “Where do we begin?” Do you have any suggestions for these places that are searching for answers to begin the land development and building processes?
BJ: Where to begin differs around the world, but the common element needed for infrastructure improvements is a good understanding of ‘where’ the infrastructure is. A solid base map with good survey control is a good place to start. Sharing base map data can deliver a lot of efficiencies by eliminating duplicated efforts, but also understanding where other infrastructure exists, either planned or existing. The Community Maps program allows free access to base map data, to internal and external organizations including local businesses and the general public.
This data can be used free with ArcGIS Explorer with a standard web browser. Community Maps eliminates the costs to an organization to publish data by eliminating the need for setting up and maintaining the computing infrastructure.
** This interview first appeared in Asian Surveying and Mapping magazine – November 2011
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Brent Jones, PE, PLS, spearheads the global marketing for the Surveying, Engineering, and Land Administration markets at Esri, the largest geographic information system (GIS) software provider in the world. He works with national cadastre agencies, national surveying and geodetic agencies, state and local governments, surveyors and engineering firms around the globe to improve their organizations with GIS. As a professional engineer and land surveyor, Brent has worked in civil and environmental engineering, utility design and construction management, and surveying/GPS, as well as extensive environmental permitting and regulatory compliance.
He has supervised the development of utility software applications, managed GIS data conversion, database design, and software development teams. In addition to work in utilities, GIS landbase mapping, data accuracy, and addressing, he has brought to market modular software tools for consequence and risk analysis. Participating professionally at the highest levels, including past president and board member of the Geospatial Information and Technology Association (GITA) and current board member of the Open Design Alliance (ODA), Brent has an ongoing commitment to his profession. He is a sought after speaker, coupling his vision, sense of humor, and ability to explain complex problems to a broad audience. His current work includes developing cadastral systems in developing countries, bringing survey accuracy to the GIS community, and developing data management solutions for design and construction firms.
