Whether you are glad that the HPMS season will be ending soon, or stressed that the deadline is looming, or both, you owe it to yourself to check out FME-based tools for HPMS.
Why not? At its core, FME provides a comprehensive set of data ETL tools that extend beyond the spatial domain. Moreover, it provides a platform to design, test, develop and document your workflow which is highly adaptable to changes in requirements as well as data sources.
At the GIS-T 2016 Symposium in Raleigh NC, Dave Campanas of Safe Software and I jointly presented FME & ARNOLD: Superman to the Rescue! After the session, Kyle Konterwitz, GIS Manager of Kansas DOT, approached me for generating a report using FME, something they had attempted for some time now – a project feature report segmented by Functional Classification and NHS designation, as well as several administrative and political boundaries.
At first glance, this commonly-requested report is conceptually simple. A deeper look into the requirements and data sets resulted in the following multi-step process:
- Merge HPMS segments based on functional classification and NHS code
- Join (overlay) project events with the events resulting from Step 1
- LRS geocode the events resulting from Step 2 to turn it into a feature dataset
- Overlay line features from Step 3 with boundary features to get the attributes from the boundaries
- LRS reverse geocode the result from Step 4 so each feature will have the correct From Measure and To Measure values in its attributes
- Optionally, remove sliver project segments as a result of discrepancies between the data layers
Out of the box, FME does not provide a direct solution. With the help of LinearBench® custom transformers such as LRS_EventMerger, LRS_EventJoiner, LRS_Geocoder, and LRS_RevGeoCoder, the process was made clean, friendly and adaptable to changes.
The second challenge came from Dave Blackstone, GIS Manager of Ohio DOT, who would like to summarize a subject event data set over a reference data set for key statistics, including length-predominate stats, among other things. This capability is already implemented in LinearBench® Analyze; still we decided to also offer it as an FME custom transformer, and LRS_EventSummarizer was born. The following workspace shows the simple workflow for this challenge:
Partial result of the report is shown in Table 1.
Table 1 UDOT’s AADT Summary Statistics over Speed Limit Segments
[table id=1 /]
While the 2015 HPMS season will end shortly, knowing FME is there to help you with future HPMS challenges may just make the off season more enjoyable!