Wishlist/Auto Align Map

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(Auto aligned map: added some reasoning)
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Map that is automatically aligned to the north.
 
Map that is automatically aligned to the north.
  
With an accelerometer it will be possible to make a compass. When the Neo1973 is used
+
For this a compass is needed (see [[Wish_List_-_Hardware#Digital_compass]])
for navigation it is useful if it always shows the map so the north of the map
+
 
 +
When the Neo1973 is used for navigation it is useful if it always shows the map so the north of the map
 
always points to the north. When rotating the Neo1973 the map will rotate the other way
 
always points to the north. When rotating the Neo1973 the map will rotate the other way
 
to keep north pointing north.
 
to keep north pointing north.
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----
 
----
  
Unfortunately, this is only possible with a gyroscope, or a compass, you cannot tell direction with an accelerometer.
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With an accelerometer it will be possible to make a compass.
Consider the phone held vertical.
+
 
It sees an acceleration vertically down along the length of the phone.
+
Unfortunately, this is only possible with a compass, you cannot tell direction with an accelerometer. Gyroscopes won't work either because they ar relative so you still need a start point.
 +
If the phone is held vertical the accelerometers can't detect rotation, but even a 2D compass can't (if it's mounted flat). I haven't found a small cheap digital compass yet (I2C or SPI).
 +
 
 +
Consider the phone held vertical with the two sensor lined up above each other.
 +
 
 
If the phone is spun along the vertical axes, then the acceleration does not change at all, so you can't tell direction.
 
If the phone is spun along the vertical axes, then the acceleration does not change at all, so you can't tell direction.
  
 
[[Category:Accelerometer]]
 
[[Category:Accelerometer]]

Revision as of 21:34, 14 August 2007

Hardware wishes warning! This article or section documents a Hardware Wish List item, the features described here may or may not be implemented in future devices.

Auto aligned map

Map that is automatically aligned to the north.

For this a compass is needed (see Wish_List_-_Hardware#Digital_compass)

When the Neo1973 is used for navigation it is useful if it always shows the map so the north of the map always points to the north. When rotating the Neo1973 the map will rotate the other way to keep north pointing north.

If the Neo1973 is held with the face down the map will be mirrored.


With an accelerometer it will be possible to make a compass.

Unfortunately, this is only possible with a compass, you cannot tell direction with an accelerometer. Gyroscopes won't work either because they ar relative so you still need a start point. If the phone is held vertical the accelerometers can't detect rotation, but even a 2D compass can't (if it's mounted flat). I haven't found a small cheap digital compass yet (I2C or SPI).

Consider the phone held vertical with the two sensor lined up above each other.

If the phone is spun along the vertical axes, then the acceleration does not change at all, so you can't tell direction.

Personal tools
Hardware wishes warning! This article or section documents a Hardware Wish List item, the features described here may or may not be implemented in future devices.

Auto aligned map

Map that is automatically aligned to the north.

For this a compass is needed (see Wish_List_-_Hardware#Digital_compass)

When the Neo1973 is used for navigation it is useful if it always shows the map so the north of the map always points to the north. When rotating the Neo1973 the map will rotate the other way to keep north pointing north.

If the Neo1973 is held with the face down the map will be mirrored.


With an accelerometer it will be possible to make a compass.

Unfortunately, this is only possible with a compass, you cannot tell direction with an accelerometer. Gyroscopes won't work either because they ar relative so you still need a start point. If the phone is held vertical the accelerometers can't detect rotation, but even a 2D compass can't (if it's mounted flat). I haven't found a small cheap digital compass yet (I2C or SPI).

Consider the phone held vertical with the two sensor lined up above each other.

If the phone is spun along the vertical axes, then the acceleration does not change at all, so you can't tell direction.