A package for pulling data for Minnesota Department of Transportation (MnDOT) loop detectors installed on the Minnesota Freeway system in 30-second interval measurements of occupancy and volume, data which are pushed daily to a public JSON feed.
remotes::install_github("Metropolitan-Council/tc.sensors")To access documentation and for help on how to use the package, run
?<FUNCTION-NAME> (e.g. ?pull_sensor, ?pull_configuration,
?pull_sensor_ids). Access vignettes in the vignettes file to see
examples of end-to-end workflows for pulling and storing data locally en
masse. Check back for a vignettes for calculating speeds, reference
speeds, delay, and VMT from the resulting files.
Definitions come from MnDOT Data Extract documentation
- Volume The number of vehicles that pass through a detector in a given time period.
- Occupancy The percentage of time a detector’s field is occupied by a vehicle.
- Flow The number of vehicles that pass through a detector per
hour (
Volume * Samples per Hour). - Headway The number of seconds between each vehicle
(
Seconds_per_Hour / Flow). - Density The number of vehicles per mile (
Flow / Speed). See full calculation method for additional context. - Speed The average speed of the vehicles that pass in a sampling
period (
Flow / Density). - Lost/Spare Capacity The average flow that a roadway is losing,
either due to low traffic or high congestion, throughout the
sampling period.
Flow > 1800: 0Density > 43: Lost Capacity: Flow - 1800Density >= 43: Lost Capacity: 1800 - Flow
- loop-sensor-trends Data analysis and interactive R Shiny app for examining changes in regional traffic levels in response to the COVID-19 pandemic.
- Twin-Cities-Loop-Detectors
A pre-cursor to
{tc.sensors}. Contains extensive documentation and code samples that will be integrated into this package.
Maintainer Liz Roten (liz.roten@metc.state.mn.us)
@ashleyasmus, @eroten, and @sullivannicole.
