Drag as request option #24
Conversation
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Could you provide some figures for the effect of different real-world drag coefficients on the speed of scooters? The last physics class I took was probably in 2006 and having trouble gauging whether or not this has a discernible impact on routing (and also if anyone would actually use it). |
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On vehicles with a significant amount of power available (say 800w) the aerodynamics will account for the vast majority of resistive forces that need to be overcome. You can play around with some details on a site that I mention in the comments. The default value of 0.408 is taken from this webpage. Given this estimate of aerodynamic drag and applying 800w of power on a flat road with 0 headwind, it is estimated that a velocity of 51.36 kph would be achieved.
Now, let's consider a different aerodynamic position that's more upright. There's a paper that has analyzed Usain Bolt's world record 100m performance in 2009. In that paper, they estimate that Usain Bolt's Cd * A is 0.96 (1.2 * 0.8). If this value of Cd * A were used with all other options being equal, the velocity gets lowered to 38.86 kph.
As you can see, the aerodynamics of a vehicle and rider can have a significant impact - especially on vehicles that are able to output a lot of power. |
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Adding blocked label due to @landonreed's request to get approval and merging into main OTP repo. |
* Add support for indirect routes and include fares for routes via Jamaica and Woodside on LIRR * Update LIRR indirect fares and handle comparing non-zone fares
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Unassigning myself... for now. |
This refactor enables reqeusts to have inputs of the aerodynamic drag for a calculation with Micromobility travel. Since a particular user can change their position to a more-or-less aerodynamic position and certain vehicles may be more aerodynamic than others it makes sense to allow this value to be dynamically set in each request. Notes on where to find certain verified values of Cd * A are noted in the comments.