The Data Capture Challenge - Innovative Solutions
Data Capture Software
The aggressive t’ming of the project requires 100,000 poles to be positioned, labeled I and attributed in 12 months. Consequently, data capture rates needed to be predictable
and attainable. The development of proprietary data capture software allowed for
advances in both speed and accuracy. This software development included input from
Powernet with respect to attribute structure. The key features of this software are
listed.
User Friendly
The package needed to be simple and user friendly thus allowing for effective results
from personnel with limited experience. This factor of personnel experience was an
important issue in the early stages of the project. Initially some experienced operators
were available from other projects, however, the majority of operators had no industry
experience and limited computer experience. This was a consequence of the available
employment pool rather than a planned strategy. The data capture software package
had to therefore be based on providing pick lists and options rather than complicated
and time consuming data entry.
Geographic Link
The software provided a link between the data captured and the relevant spatial
information. As a result operators are able to view spatial relationships on-site using
real-time GPS and physical landbases, while capturing other attribute information.
297.This fiction has been of importance in on-site quality assurance of positional
accuracy.
Quality Assurance
The package is also capable of informing the operator of logic errors and asking for
confirmation of unusual plant combinations. It also allowed for the capture of digital
images of pole structures, gee-referenced to the poles’ coordinates. This allowed for
later off-site quality assurance of important and visible features.
Flexibility
The attribution framework within the sofisvare is flexible and able to be client
specific. Changes to this fiarnework in the early stages of the pilot project were able to
be performed rapidly and on-site.
Digital Landbases
A digital landbase of physical features, at a defined accuracy, is the chassis by which
any successfid AM/FM/GIS system operates and as such must be an integral part of
the data capture process as well. It gives the data spatial integrity. If that integrity is
available at the time of capture, quality assurance advantages are substantial. It allows
for real-time positioning checks, checks of positional relativity between items of plant
and orientation of items like pole guys and street lights. The landbase used in the
PIMS project differed between rural and urban areas. In urban areas, kerblines,
property boundaries and power pole positions were captured using photogrammetric
methods with an absolute accuracy of+/- 0.5 metres. In rural areas, road centreline
data was captured using vehicle based GPS to an absolute accuracy of +/- 5 metres. In
addition to these physical features a cadastral base was also used in order to provide
parcel information, both urban and rural, This will allow for the interfacing of
customer databases.
Portability
Field inventory, by its very nature, involves taking data capture technology out of the
ofllce and into the field. The methods used are many and varied, however, in most
circumstances three levels of portability are required: vehicle based for normal
roadside capture, vehicle based for off-road capture where the land allows for four
wheel drive access, and total portability where the contour or cover allows for foot
access only. In the PIMS project all three methods have been required. The equipment
used obviously depends on the method, ranging from personal computers with 14 inch
monitors, 12 volt hand held digital video cameras and fixed GPS for roadside capture,
laptop computers, 12 volt digital cameras and portable GPS for off road capture and
weather proof ruggedised laptop computers, portable digital cameras and portable
GPS for capture on foot. All systems must be reliable, cost effective, freely available
and physically suitable in terms of size and weight. Components have needed to be
purchased off the shelf and customised to provide systems that comply with these
requirements. Innovation and lateral thinking are prime attributes for this particular
task.
Quality Assurance
The area of quality assurance is without doubt the most challenging aspect of field
inventory. The principle of a single site visit and checking data quality after that site
visit is obviously in conflict. The very nature of field inventory dictates that data can
only be checked on site, as that is the only data source. In practice, quality assurance
procedures must be matched to data quality expectations. In the PIMS project those
quality expectations are very high. As a result, practices have been developed,
admittedly on a trial and error basis at times, that have proved reliable and consistent,
These practices fall into two broad categories: on-site and off-site.
On-site quality assurance has been discussed and includes logic and plant
compatibility checks via the data capture software, and positional accuracy and spatial
relationships via the use of physical landbases of a defined accuracy linked to real-time
differential GPS. Off-site quality assurance has seen the use of digital imagery to
allow a post-capture observation of every pole structure. This image is gee-referenced
to pole coordinates on-site, thus precluding any possibility of an image/pole conflict.
The attributes that are capable of being checked this way are entirely dependent on the
skill of the camera operator and the resolution of the image. There is an obvious desire
to maximise both factors to allow for extensive re-observation.
Where real-time differential GPS is impossible due to local topography or conditions,
post processed differential positions are required. This precludes the availability of
positional checking on-site. However, with physical landbase use and analysis of span
lengths, off-site checking of post processed positions has proved reliable. In urban
areas where there is a high proportion of complicated pole structures, there has been
the need to compromise the single visit principle. Digital imagery in these areas has
shortcomings and as a result personnel have been re-visiting some sites to confirm
data. Overall, experience dictates quality assurance of field inventory data capture.
Conclusion
This paper has focused on using available technology in innovative ways in order to
solve real problems facing utilities. Two crucial points are central to this process:
ensuring the traditional attitudes between client and contractor are rejected and
replaced with an environment suitable for innovation, and the fact that experience (or
trial and error) is a pre-requisite to success.
References:
Price,M,Pickford,P, 1996,ANUFM Beyond 2000- A Practical Case Study :AM/FM
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