You can calculate the speed with the sensor ( accelerometer) at the below link http://jahbromo.blogspot.com/2009/11/android-faire-un-speedometre-avec.html
GPS is not need to calculate the speed. On Jan 13, 8:48 am, gjs <[email protected]> wrote: > Hi, > > I think you could still extrapolate (average) speed for some trip with > intermittent GPS signals. > > If you get a GPS fix at the start of the journey and then at the end > you can calculate an average speed based on the time duration and > straight line distance between these points, any additional points > (GPS or course grained towers/wifi/skyhook) during the journey would > be a bonus to increase the accuracy of the speed and distance calcs. > > This depends on whether you actually require real time speed ? > > Regards > > On Jan 13, 5:37 pm, Bob Kerns <[email protected]> wrote: > > > > > > > > > I've never gotten around to experimenting to see just how good you CAN > > get -- but there are some reference points that should help > > considerably. > > > * Gravity > > * The magnetic field > > * Any period of low acceleration noise in the vicinity of about 1 g > > total acceleration probably indicates it has been set down on a > > surface (or in the original scenario -- the car has come to a stop). > > > There other possibilities in other situations: > > * Camera data can indicate relative motion > > * Acoustical echoic signature and ambient sounds > > * Wifi transmitter signal strengths > > * 3G signal strengths. (Hey, I'm outdoors, maybe try GPS again!) > > * Sonar! > > > A typical android device has more senses than humans. We synthesize an > > understanding of our location and environment via a process of sensor > > fusion. There's more opportunity for this sort of thing on Android > > than Nintendo, as there's more processing power available and more > > sensors to gather information -- especially when connected to a power > > source or otherwise on a larger power budget than a cell phone. Look > > at Dempster-Shafer Theory and Kahlman filters for techniques to handle > > this sort of process. > > > On Jan 12, 5:10 pm, keyboardr <[email protected]> wrote: > > > > I know Nintendo originally tried to use accelerometers to figure out > > > where it was pointing, and while that's theoretically possible, in > > > practice the accuracy just isn't good enough. The acceleration most > > > of the time is small enough that even the slightest error will throw > > > the whole calculation way off, and since you're relying on all of your > > > previous results, errors get compounded over time. That's why > > > Nintendo switched to an IR camera setup. > > > > On Jan 12, 7:22 am, cellurl <[email protected]> wrote: > > > > > couldn't you use the accelerometer? > > > > Integrate that? Use time. s=Integral(a dt) > > > > If that doesn't work, look to skyhook wireless! > > > > -cellurl > > > > > On Jan 12, 8:20 am, Brill Pappin <[email protected]> wrote: > > > > > > Well you pretty much need distance traveled over time to find speed, > > > > > so anything you can do to determine distance travelled should allow > > > > > you to calculate the speed. > > > > > > For instance you could use cell tower location, but I wouldn't class > > > > > it as even remotely accurate. > > > > > If you want to give an actual real value, your going to need the > > > > > accuracy of the GPS unit. > > > > > > - Brill Pappin > > > > > > On Jan 11, 11:13 pm, darrinps <[email protected]> wrote: > > > > > > > All the examples I see use GPS, and I have that working just fine > > > > > > but > > > > > > I've noticed that every time I'm in a car, that unless the phone is > > > > > > close to a window or the windshield the GPS does not work so... > > > > > > > I thought that there should be a way using course grained location > > > > > > between cell towers. Does anyone know if this is possible and if so > > > > > > might know where I could find some sample code please? > > > > > > > Thanks! > > > > > > > Darrin -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
