Designing a GIS data collection job

Suppose you are assigned the task of using a CMT GPS field data collection program to inventory all the fire hydrants and all the street trees in the southeastern section of the city. The data will be incorporated into the city’s GIS database.

Some factors to consider for a GIS data collection task are:
1) Feature Topics of interest
2) How long to occupy each point, or how often to record a node for a path
3) Feature descriptions of interest

For this job, the geographic features of interest are Fire Hydrants and Street Trees. These are considered Point Features because only one  (X,Y,Z) position will be recorded for each item. As the Fire Hydrants and the Street Trees do not share the same set of attributes, you want to group them into two separate Feature Topics.

How long to occupy each point depends on the quality of the GPS receiver and the accuracy requirement of the data collection job.

The data collection software will record the location coordinates when it is able to compute a solution for the occupied point.

Your GIS analysts will tell you what descriptions they would like you to record for each Feature Topic. Let’s say, the attributes of interest for the fire hydrants, are:  Type and Condition, and the attributes of interest for the street trees are:  Street Name, Species and Size.

You could simply grab your data collector and head out to record the GPS coordinates of each fire hydrant and street tree, and busily enter the description for each entity.

Or, you could set up a Feature List ahead of time to facilitate the data collection process. Basically, a Feature List contains the setup for one or more Feature Topics, each with its associated data collection parameters and Attribute/Value database. When you use a Feature List with a data collection job, you can simply confirm the displayed data collection parameters; and you will be able to select the appropriate Attributes and Values rather than having to manually enter the descriptions.

Essentially, the Feature List embodies the design of your data collection job. A well thought out data collection design will produce well organized and consistent data that will be useful to your GIS analyst.

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