3 ms·
How does this work? I understand if you know the true north and the magnetic north, you can get the difference, but I assume a compas only can measure one of th
by PanMan 14y ago
How does this work? I understand if you know the true north and the magnetic north, you can get the difference, but I assume a compas only can measure one of them (the magnetic one). How do they determine the 'fault' in the signal with just 1 signal?
- flog 14y agoAnd what what if the stock is magnetic? ("Where's the fridge magnet isle?") ... and doesn't the earths magnetic fields change also? There's a number of questions I'd have about the stability of the data being collected and how quickly it'd go stale.
- wpietri 14y agoEvery phone using the app can contribute to your map data. If you combine magnetic data plus wifi data plus user behavior data, I expect you'd be able to continue to provide good 3D data to users. I'd bet the hard part is getting building owners to update things regularly. Who's going to remember to change the map when the grocery store moves the cereal from aisle 2 to aisle 7?
- asmithmd1 14y agoIt must require you to be moving in a straight line; otherwise you have just one parameter, the angle of the magnetic field, and there is no way for that one parameter to specify your location in 2 dimensional space.
- rrmm 14y agoI would guess they would have to use the accelerometers and gyros on the phone to get a plane curve, along which they would then have the gradient and could match against a stored database.