Global Positioning System Reference
In-Depth Information
5.6
Mapping Everywhere
Simultaneous location and mapping (SLAM), which will be discussed in more
detail in Chapter 9, is a future Whereness application that comes as a spin-off
from guidance applications in mobile robotics. It is a positional information
scavenging system that collects potential map information from positioning
measurements and thus builds maps, while the main system is simultaneously
providing the positional information to more conventional applications such as
guidance. Since these systems can be greatly improved by using map matching,
the repeated use of SLAM builds, improves, and uses maps simultaneously. The
value of the map is increased and it is maintained automatically. It can discover
new areas to be mapped and highlight changes to existing maps. A validation
method (perhaps provided by an agency) is required to accept any changes before
they become persistent.
The markets for SLAM are mapmakers, GIS organizations, and map users.
Map validation service providers would sell the maps that have been checked to
many current GIS and map users including building and facilities managers,
utilities, the construction industry, local authorities, and governmental agencies.
All these users would most likely be in partnership with the more general
Whereness service providers.
Benefits of the application are the creation of free maps as a by-product of
other commercial applications. Map attribution can be automated if features can
be identified using software, and map maintenance can be improved by changes
being automatically highlighted. Existing mapmakers may have to lower prices if
SLAM is taken up by open-source mapmakers universally.
The weaknesses of SLAM are the users must be persuaded to participate since
there are no direct benefits unless incentives are included in some way. Some map
attribution is still needed after map creation and certainly validation would be
necessary. In some areas SLAM may be forbidden for security or legal reasons.
Hackers and criminals may seek to create false maps.
SLAM has an exacting requirement for accuracy and coverage (the higher the
better). Galileo, with <1m accuracy, will be very useful. There is no specific need
of real-time communications between mobile mapmakers and central systems.
The systems will collect map fragments and meld into a tessellating whole GIS. It
is unlikely that this process would ever be entirely automatic because of
ambiguities. (See details on open mapping in Section 8.7 and SLAM in Section
9.4).
5.7
Locative Media
Locative media is a very important part of the future electronic media. By using
positioning technology to trigger the delivery of multimedia in particular places,
engaging experiences either individually or in groups can take place. For example,
