I've thought about that once. An accelerometer may estimate the frequency of bumps, but their depth would require informing the app about some very specific technical of information (such as car weight and some coefficient to express how its dampener has been tuned - that or the car's resonance curve: see http://en.wikipedia.org/wiki/Tuned_mass_damper) in order to estimate bump depth. Cracks can only be assessed confidently using a camera and computer vision algorithms. Measuring soil humidity is almost impossible (at best with very interlligent computer vision), soil compaction would require special resistance measurement equipment. I have no idea how to estimate grain size with automated methods, but maybe computer vision with some really good (and expensive camera) could do it.
But all of these characteristics can be "well guessed" by humans when given examples to compare with. I also wonder if doing this wouldn't be similar to the measurement of "traffic patterns" (mostly "measured average speed"), which has been proposed for OSM a few times and rejected (because they change too often, are hard to measure and require breaking line segments into many pieces to achieve good resolution in the representation of the "average speed"). On Sat, Jan 4, 2014 at 11:49 AM, Gerald Weber <gwebe...@gmail.com> wrote: >> If you want a full justification of why a particular way was >> classified as it is, then I think you need a reasonably full >> description of a surface that would be useful for various kinds of >> routing. Considering what we've debated so far and also the >> characteristics that are used in many road quality assessment systems >> out there, this would involve collecting at least the following >> information, each on its own tag: >> - average frequency of bumps >> - average depth of bumps >> - average frequency of cracks >> - average width of cracks >> - soil grain size >> - soil humidity >> - soil compaction > > > Sounds to me like a task for a smartphone app, combining GPS tracklogs with > accelerometer and compass info you could get a fairly automated system for > evaluating the smoothness of a road. Perhaps an Osmand plugin which could > generate gpx wayponts relating to the smoothness of the road? > > _______________________________________________ > Tagging mailing list > Tagging@openstreetmap.org > https://lists.openstreetmap.org/listinfo/tagging > -- Fernando Trebien +55 (51) 9962-5409 "The speed of computer chips doubles every 18 months." (Moore's law) "The speed of software halves every 18 months." (Gates' law) _______________________________________________ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
