Supporting Geospatial Data in the Field
2.2.2 Pen Based Tablets
The pen based tablets are a step down from laptops in resources, but still give that user a
reasonable screen and allow they user to run a wide range of available off the shelf
software. The pen based aspect of the tablets mean that a different approach to designing
interfaces must be developed. The screen size is large enough that users can absorb
about the same level of information from geospatial data as on a laptop screen.
2.2.3 PDAs
The PDA market is moving very rapidly today and a large number of business sectors
routinely use PDAs in some aspect of their field operations. The applications include
both data gathering as well as directional applications. Some of these applications make
use of some geospatial data. Using PDAs for applications involving serious use of
geospatial data, however, is just beginning to take off. While the resources available on
PDAs continue to increase, there are some aspects of a PDA that require careful software
development. Screen size is the most critical issue in terms of software dealing with
geospatial data. Laying out a user interface that provides software options and renders
usable map/image information on the screen places significant constraints on both the
interface and software design.
2.2.4 Wearable Computing
Like PDAs, wearable computer technology is developing rapidly. The resources
available for a wearable system are increasing very quickly. Input devices for wearables
are readily available, but they differ dramatically in how hard they are to use. In addition
new approaches, like interpreting eye movement are on the way. The screen size on a wearable is even more critical than on a PDA. The small size of the screen image
combined with the issues of working with the screen image are limiting what can be done
with visual data such as geospatial data. Two important issues worth mentioning are the
difficulty of working on the edges of the screen image and locating a precise point in the
screen image. These restrictions are likely to limit the way geospatial data can be used in
the field. While traditional applications of geospatial data may be hard to implement,
wearable computers also bring new opportunities. One very interesting new possibility is
the concept of augmenting virtual reality (Figure 3). To support more traditional
applications, it is likely that wearables will be used in tandem with other computing
devices.
Figure 3. An example of augmented vision using a wearable computer.
2.3 GPS
GPS systems are rapidly becoming part of all field applications involving geospatial data.
While most of our discussion of working with geospatial data is useful without
employing GPS, we assume that it will be part of most applications.
3. SOFTWARE DEVELOPMENT CONSIDERATIONS
The issue for developing application software for using geospatial data in the field
depends greatly on the type of equipment being used. In Section 2 we briefly examined
some of the characteristics of the computing devices likely to be used in the field.
Laptops have become so powerful that other than screen size and battery life, they are
essentially desktops. Even the available screen size does not greatly limit the use of
geospatial data. The only real concern when developing interfaces for applications is
that care must be taken to insure that the interface layouts used make wise use of the
available screen size.
Pen based tablets have essentially the same screen size issues as a laptop. The fact that
they are pen based obviously means a somewhat different approach to inputting data, but
does not greatly change the basic approach to handling geospatial data.
The real issues come with computing devices that have drastically reduced screen size.
PDAs and wearables are two examples of current technology that have small screen sizes.
In the remainder of this section we look at two issues. The next subsection looks at the
issue of interface development and Subsection 3.2 looks at approaches for working with
geospatial data on a small screen.
