Last spring I posted an article discussing some shortcomings of the PBF format and proposing a much simpler OSM interchange format called VEX. …

Infrastructure for Fast Geographic OSM Extracts — Conveyal is developing software that performs fast geographic extracts of up-to-date OpenStreetMap data anywhere in the world and delivers them on demand in compact binary formats. The results are promising, and we are now using Vanilla Extract to fetch road network data on demand for use in Transport Analyst. Our needs At…

Simpler OpenStreetMap Data Exchange Formats — The PBF format appeared at the end of 2010 as a compact binary alternative to the voluminous XML representation of OpenStreetMap data. It was a major step forward, reducing the size of files by half or more and making OSM processing much less resource-intensive. I have made heavy use of…

What is Profile Routing? — Journey planning is usually framed as an optimization problem: it’s about maximizing or minimizing some criterion. Problems where we must find the best combination or sequence of steps to meet a quantitative goal have been studied in great detail. There’s a specific term for solving them (combinatorial optimization) and a…

Capturing Service Variation in Accessibility Analysis — As part of our collaboration with the World Bank to develop analysis tools that support improved transportation outcomes in cities around the globe we have added functionality to OpenTripPlanner that allows efficient calculation of best, worst and average travel times.Trip planning services usually tell you the fastest or easiest way…

A resource-efficient open source routing library — The Bliksem Consortium, of which Conveyal is a member, has released its C implementation of a timetable-based public transport routing algorithm under an open source license at http://github.com/bliksemlabs/rrrr. The code is compact and fast enough to run directly on a mobile phone, providing routes even without an internet connection. For…

Routing with Real-time Vehicle Arrival Updates — OpenTripPlanner and other trip planning systems typically calculate itineraries using arrival and departure times from published timetables. An increasing number of agencies are providing these data openly via GTFS and other formats. However, because of delays, cancellations, and other unforeseen changes in service, the true optimal path on any given…

Visualizing urban accessibility with OpenTripPlanner Analyst — OpenTripPlanner has made rapid progress over the last few years and is now being used in production systems providing multi-modal itineraries to public transit riders, pedestrians, and cyclists around the world.However, the routing engine at its core has the potential to answer much more general questions about efficient paths through…