It only takes one phone: You have the phone generate a tone and detect the shifted tone off of whatever object reflects it, like radar. ;)
On Jan 14, 7:52 am, Kostya Vasilyev <[email protected]> wrote: > Right, it takes two phones. > > You start playing sound on one and throw it out the car window, then measure > the Doppler effect with the other. > > Great thing is, you can get a speed reading on the way back, if you pass by > the same place. > > -- Kostya > > 2011/1/13 Hogus <[email protected]> > > > Don't be ridiculous, you can't use doppler shift if the source and > > recorder remain at the same position relative to each other. > > > On Jan 13, 5:56 am, Spiral123 <[email protected]> wrote: > > > Play a tone and record it at the same time. The doppler shift should > > > give you the speed. Works for galaxies. > > > > On Jan 12, 9:52 pm, metal mikey <[email protected]> wrote: > > > > > You could use the phone's camera to take video of the car's > > > > speedometer and use image analysis to determine what the speedometer > > > > indicates the speed as. LOL :D > > > -- > > 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]<android-developers%[email protected]> > > For more options, visit this group at > >http://groups.google.com/group/android-developers?hl=en -- 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
