Global Positioning System Reference
In-Depth Information
more freedom to roam if their caregivers know where they are at all times. The
same approach can also be adopted for the care of animals.
There are two approaches. First, an active approach, whereby the position of the
person is determined by equipment carried by him or her, which then
communicates with the infrastructure. The second approach is passive, where
sensing systems are used to recognize movements, usually within a bounded area.
The advantage of active systems is that they are high-performance and can be
used to follow movements anywhere, but it requires a Whereness device to be
carried that may be bulky, heavy, expensive, prone to failure, and requires a
working battery. The passive system, in contrast, requires no equipment but will
only work in certain areas covered by the fixed sensing system (e.g., surveillance
cameras, floor pressure sensors, passive infrared systems, and volumetric
ultrasonic systems). A second problem with the passive approach is the reliable
identification of the target. If there is more than one person being tracked, a
secondary system is needed to identify them.
Markets for this service would be mostly the caregiving agencies rather than
the individuals in care. These would include:
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Blind people;
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Deaf people;
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People who are physically or mentally challenged;
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Children in care;
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Vulnerable workers in difficult areas;
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Prisoners in the community;
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Pet management;
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Farm animals;
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Endangered species in the wild.
Benefits are a reduction in the cost of care since automation gives caregivers
more freedom and flexibility, which can decrease stress of users and caregivers.
Weaknesses, however, can come from abuse by criminals or poorly
performing caregivers. Exploitation by authorities is also possible, eliminating
people from areas where they are still needed. An overreliance on radio (always
subject to potential interference), poor battery performance in the active case, and
radio coverage are all areas that need to be carefully managed.
Performance requirements are exacting. High levels of positioning accuracy
are needed (<10m in general) and very low latency. Very high levels of security
are required. Tracking needs to be continuous, with positions recorded second by
second. There may be a need to extend coverage indoors using sensor technology.
This is probably the most demanding of all Whereness applications.
Very good quality mobile data communications outdoors is needed, with
possible need for roaming between networks. A GIS is required to manage geo-
fences either centrally or locally to raise alarms when targets stray. Intelligent
