The newest trend and current buzzword in Geographical Information Systems is "mobile GIS." For surveyors mobile GIS is anything but a new trend. We have been using it for years, perhaps without even realizing it.
So what exactly is mobile GIS? The consensus definition for mobile GIS is: "a leveraging of technologies that allows the Enterprise Data Base to be accessible to field or other remote personnel." What exactly does this mean to the surveyor? Data collection? Not exactly. Don't confuse mobile GIS with mere data collection. It's more than that. With mobile GIS, the surveyor can basically take his office resources right to the jobsite.
Do you remember that euphoria you experienced the first time you set out a program in your data collector? The "check" angle on the display of your total station was pointing right down the middle of the brass cap you were checking into and the measured distance matched the readout on your data collector right to the hundredth?
Nearly everyone in the profession recognized this as a giant leap forward, both practically and conceptually. Now we could keep all of our coordinate data for a project neatly and efficiently in digital format ready to go to work at a moment's notice without fumbling through reams of paper and re-entering coordinate data over and over. But what about the rest of the information we use?
Eventually (by hook or crook) GIS data sets were created, very often from the surveyor's own products. Some enterprising surveyors soon devised clever ways to leverage these data sets. One popular method was to download control point information, upload point values into a handheld global positioning receiver and then utilize the navigation feature to search for "control" points.
Is this mobile GIS? Well, almost, but not quite. In reality, mobile GIS is the total integration of mobile (in the field) GIS tools with the desktop and the Internet. And that concept naturally raises questions like: "Just what are these mobile GIS tools?" "How can surveyors use them?" and "How do I take my data to the field?"
These are fair questions. Let's examine some of the popular solutions currently in use. As you read, many of them will be quite familiar.
ArcPad is an ESRI product that has been around for a few years. It was one of the first GIS products that ran on Windows CE devices and also interfaced in a standard Windows GUI (Graphic User Interface). ArcPad has some powerful features. It lets the user edit or create features from the keyboard or with a pen. Its multilayer format is particularly useful in the field. All project layers are active for querying or editing.
ArcPad's weakest feature (in my opinion) is its "out of the box" data collection capability. ArcPad only supports a limited range of GPS receiver models and has no real "collection" menu.
The ArcPad Application Builder for the desktop is a sort of design studio that creates custom "forms" for data collection. It also creates custom applications and allows the user to expand the types of readable files and user services, including GPS data. ArcPad supports shape files, and .bmp, .jpg and MrSID file formats.
IMap is the SOKKIA version of a TDS-developed mapping product called Solo. This highly utilitarian product is quite strong for data collection and navigation using GPS. IMap is better at data collection when connected to a GPS device than data editing; it has a built-in ability to make custom data collection "data dictionaries." IMap can display shape files or export shape files but it cannot edit shape files. All the editing must be performed on the .UDF (Project) file. IMap also runs on the desktop but as a separate license. It supports TDS CR5 files for easy interfacing with total stations, which can share that format.
A device that fits in your shirt pocket and has real computer power is bound to be a hot item. The Compaq iPAQ PDA was the "leader of the pack" almost from its introduction. This Windows CE device can run all of the popular mobile GIS applications. The main criticism of the iPAQ is that it lacks the requisite durability for heavy outdoor use.
The TDS Recon has emerged as the "ruggedized" PDA option to many. It has proven to be not only durable enough to meet surveyors' needs as a data collector, but powerful enough to run CE-based GIS software.
These devices interface with GPS receivers as well as total stations.
Tablet computers are the newest entry in the mobile GIS mix. They run a special version of Windows XP. Just as Windows CE is a special version of Windows for small devices, the XP program used on tablet PCs is modified. Since tablet PCs are pen-based like CE devices they are somewhat "reverse engineered" with respect to their primary input devices.
The tablet PC combines the best features of the laptop and the PDA. Tablet PCs come with the power of the notebook and the pen-based utility of the PDA along with outdoor friendly screens and USB ports. Large batteries for extended field use are marketed as accessories, as is true of the mouse and the external keyboard. Tablet PCs are available with features quite comparable to notebook models. Some "convertible" models even have attached keyboards. Generally speaking, what runs on Windows XP will run on a tablet PC.
With a notebook, such as those in the Panasonic Toughbook series or the Fujitsu Stylistic series, the user has the capability and power to load the entire GIS database for a small community. This solution provides the most options but the least mobility. Some models are ruggedized and equipped with touch screens for easy field editing. Besides having full processing capabilities, most support wireless communications to central databases.
Hardware/SoftwareThe Trimble GeoXT XM is a popular and powerful mobile GIS tool. It's a DGPS receiver and Windows CE computer all in one instrument. There are no cables to worry about unless you want to add peripherals. For data collecting, Trimble's TerraSync data collection software allows the user to collect data in the field using simple or complex "data dictionaries" created in Pathfinder Office.
TerraSync has minimal file type support and has a very limited range of feature editing functions. But, the GEO XT is a true Windows CE device and adding ArcPad is certainly a viable option for surveyors using mobile GIS. Pathfinder Office allows post-processing of collected features, and it exports to all of the popular standard file formats.
The Future Looks BrightThe mobile GIS playing field is rapidly filling up. Government mandated programs like GASB-34 (Governmental Accounting Standards Board Statement 34) have agencies from coast to coast involved in resource mapping. Police officers are fast becoming mobile GIS users. Not only are Computer Assisted Dispatch programs generated from GIS databases, but school buffer zones are now being enforced using GIS technology.
Location-based services is another niche market. This is new technology that utilizes GPS (geolocations) to track activities. It is already becoming so popular that the demand has nearly outstripped the infrastructure for delivery.
These are areas in which surveyors may find themselves involved in some capacity, so mobile GIS is certainly something for surveyors to keep a close watch on.
The author acknowledges the existence of many more mobile GIS hardware/software solutions. Only those products actually field-tested are profiled here.