Orion Trip Generator

• takes in JSON S3 files (API output) to generate trips

What is a trip?

• uniqueness is defined by (vehicle_id, route_id, direction_id) staying consistent with every transit state.
• If this tuple is different in the next state, then we end the trip. If we see a tuple that we didn't see last state, we start a new trip.
• when a trip ends, we write it to a JSON file in S3 (agency_id-vehicle-id_route-id_direction_id-start_time-end_time). We can worry about compressing it or loading it into some databases later.

What is a state?

• it's a snapshot of where all Muni vehicles are with a timestamp

Why?

• our goal is to get the speed & reliability of routes.

• An easy way of approaching this problem is to look at individual trips and then get data about them along route segments.

• Storing trip metrics also makes it easier to eventually quickly handle more complex analysis due to aggregated metrics.

• our goal is to make Muni's GPS data open and accessible to use.

• making trip data accessible via S3 keeps individual file sizes small and is straightforward & logical for open-data users to retrieve.