Interesting that this kind of alternative-route-calculation is now beginning to creep into car navigation. It is a well known (and unsolved) problem of pedestr

Interesting that this kind of alternative-route-calculation is now beginning to creep into car navigation. It is a well known (and unsolved) problem of pedestrian navigation for blind people. Often, the shortest path is not the best, period. Especially because dangerous or uncomfortable sections of your route will actually cost you more time then going the longer, but more safe alternative. However, its a question of what data you have. For blind pedestrians, the insight until now was always that we simply dont have the data to be able to calculate this reliably.