GraphHopper provides routing and route optimization APIs. It was created in 2012 and combines open source routing software with algorithms to solve vehicle routing problems. The route optimization API finds least cost routes that visit multiple locations in a specified order, taking vehicle capacities into account. It uses various search algorithms like branch and bound to optimize routes for applications like deliveries. The route optimization editor allows interactive solving of traveling salesman, vehicle routing and other problems. Demonstrations of optimizing Dublin pub routes gained significant publicity for GraphHopper.

1. GraphHopper Route Optimization
Stefan Schröder

2. ● Fast and Flexible Directions API
● Lightweight API to solve heavy routing problems
What is GraphHopper?

3. ● 04/2012 – Peter Karich published OS GraphHopper routing
based on OSM
● 06/2013 – Stefan Schröder published jsprit, a toolkit to solve
vehicle routing problems
● 04/2015 – we joined forces to develop the GraphHopper
Directions API
Brief history

4. Directions API

5. Route Optimization API
● Difference between Routing and Route
Optimization API
Least cost path
from A to B
Least cost paths with
via points
A
B
A
B
C
D
E
A
B
C
D
E
Least cost route by
ordering of via points

6. Route Optimization API
1. Geocode
2. Snap Geocodes to
networks
3. Calculate n x n travel
times/distances
4. Optimize
Friedrichstraße 52
lon,lat
1
n
1 n

7. Vehicle Routing Problem
● VRP: Given m vehicles with capacity restrictions and n
customers, find vehicle routes that minimize
transportation costs.
● TSP: Round trip visiting every location once
● Last mile deliveries, health care, garbage collection,
technicians, ...
● Challenges: Search space, Example 50 L-TSP

8. Search algorithms
● Exact methods – Branch & Bound
● Meta-Heuristics – Tabu Search, Simulated
Annealing, etc.
● Ruin and Recreate – Large Neighborhood
Search Threshold Acceptance and Simulated
Annealing

9. Route Optimization Editor
● Switch to Route Editor and solve problems live
● TSP
● TSP-Relation
● VRP
● VRP-Relation
● VRP-Bike
● VRP-Min-Max

10. Problem Berlin

11. Sufficient capacity - TSP

12. Direct sequence of 37 & 38

13. VRP

14. VRP with relation

15. VRP – min-max compl. time

16. VRP – min-max by foot

17. Shortest route through
Dublin avoiding pubs?

18. Dublin – “avoid pubs”

19. Dublin – “avoid pubs”

20. Publicity?
● handful retweets
● <100 blog readers
● pointer to this: “there's someone trying to drink in
every pub in Dublin, might be another interesting
demo for you.”

21. Shortest route through
Dublin visiting all pups?

22. Dublin – “visit all pubs”

23. Publicity?
● many retweets from all over the world
● >3000 readers
● on reddit
● a day on the front page of hacker news with 84
points

24. Dublin – “visit all pubs”

25. GraphHopper.com
stefan.schroeder@graphhopper.com