On Sat, Jan 10, 2009 at 4:11 AM, Mathias Agopian <[email protected]> wrote: > > On Fri, Jan 9, 2009 at 5:31 AM, Sean McNeil <[email protected]> wrote: >> >> What you are trying to do cannot be done. Accelerometers give you a >> vector to GC whereas the G1 has a compass which gives you yaw/pitch/roll >> to north. > > It is not too difficult to calculate yaw/pitch/roll from the > geomagnetic vector and acceleration vector. > > You can find all the math in cupcake's SensorManger, see > getRotationMatrix() and getOrientation(). > > > Of course, with a device that only has an accelerometer, you cannot > calculate "yaw", but only pitch and roll. > > Mathias > >> Hi Mathias I have seen a device file for compass in "system/core/init/devices.c" in android sources. Also I have read the ak8976 driver sources in android msm kernel sources. I also could see a daemon called "akmd" in android. I guess by the driver code that this daemon is calibrating yax, pitch and roll from sensors' data and again sending it back to driver through a driver. Where the sources of this daemon are?
>> 伊泽 wrote: >>> hi pramod gurav, >>> >>> I think we have the same problem,the lis302/lis331 sensor cannot provide >>> yaw/pitch/roll data while we feel hard to emulate G1's compass feature. >>> >>> But I thought there would be some method to emulate that,,,we get the >>> x/y/z >>> and change them to yaw/pitch/roll through a model... >>> >>> hmm,,that's not easy,i think. >>> >>> thanks >>> --wxc200 >>> >>> >>> >>> ============ >>> 自由之精神，独立之人格 >>> ============ >>> Zsa Zsa Gabor - "I'm a great housekeeper. I get divorced. I keep the >>> house." >>> >>> On Fri, Jan 9, 2009 at 6:59 PM, pramod gurav <[email protected] >>> <mailto:[email protected]>> wrote: >>> >>> On Fri, Jan 9, 2009 at 3:27 PM, 伊泽 <[email protected] >>> <mailto:[email protected]>> wrote: >>> > hi >>> > >>> > why not port your driver to android? >>> > That would not be too hard. G1 has a compass and >>> > gravity accelerometer sensor,it can detect pitch/roll/rotation >>> and motion. >>> > Also Iphone ,Borqs and Openmoko has the LIS3XX chip as their sensor. >>> > this is openmoko's: Accelerometer data retrieval >>> > But lis3xx sensor is a gravity accelerometer sensor,it has >>> > not function as G1's compass,when you put phone on the flat >>> table ,it cannot >>> > detect rotation. >>> > >>> > Ofcourse,you should choose your sensor depend on the app design. >>> > >>> > thanks >>> > --wxc200 >>> > >>> > >>> Hi I have ported the drivers according to android. >>> The sensors on my h/w are ak8973(magnetic x,y,z) and lis302dl(acc >>> x,y,z). >>> They do not give the yaw, pitch roll. >>> I could get the values on my android application. >>> But cant get the yaw, pitch and roll. I was expecting that Android can >>> calibrate >>> these values as my h/w have no support. >>> >>> >>> >>> > ============ >>> > 自由之精神，独立之人格 >>> > ============ >>> > Joan Crawford - "I, Joan Crawford, I believe in the dollar. >>> Everything I >>> > earn, I spend." >>> > >>> > On Fri, Jan 9, 2009 at 3:26 PM, Mathias Agopian >>> <[email protected] <mailto:[email protected]>> >>> > wrote: >>> >> >>> >> Hi, >>> >> >>> >> Android doesn't "require" yaw / pitch / roll per se. In theory, >>> well >>> >> written applications should check for the presence of these >>> sensors. >>> >> Unfortunately, in Android 1.0 there wasn't an easy way to >>> integrate a >>> >> new sensor h/w. >>> >> >>> >> I think it is more sane to target the "cupcake" release of Android, >>> >> which a work in progress is available in the main git repository. >>> >> >>> >> Future (cupcake) applications will be able to use the SensorManager >>> >> to calculate the yaw / pitch / roll from the acceleration and >>> magnetic >>> >> data (this is actually more precise than the data coming out of the >>> >> driver!). Additionnaly, there is a HAL module to implement your >>> sensor >>> >> h/w which describes precisely what is expected from the higher >>> layers >>> >> (see sensors.h). >>> >> >>> >> A sensor h/w can expose yaw/pitch/roll if it wants to, but is not >>> >> technically required; the framework will expose a "fake" >>> >> yaw/pitch/roll sensors if one is not published by the sensor >>> HAL and >>> >> if Acceleration and Magnetic data are available. >>> >> >>> >> Note that the definition of the axis at the h/w level have changed >>> >> between 1.0 and cupcake, so be sure to read carefully the >>> >> documentation in sensors.h. >>> >> >>> >> >>> >> Android doesn't do ANY calibration on its own. The drivers >>> and/or HAL >>> >> modules are expected to do this. >>> >> >>> >> >>> >> In "theory", all you need to do is implement a sensor HAL module >>> >> properly (as documented in sensors.h. pay extreme attention to the >>> >> definition of the axis and units). Unfortunately, in the >>> current git >>> >> repository there are no sample code of a sensor HAL module, which >>> >> makes this task more difficult; however we will fix this >>> problem soon >>> >> by including the G1 HAL module source code, stay tuned. >>> >> >>> >> I hope this helps. >>> >> >>> >> Mathias >>> >> >>> >> >>> >> On Thu, Jan 8, 2009 at 9:45 PM, pramod gurav >>> <[email protected] <mailto:[email protected]>> >>> >> wrote: >>> >> > >>> >> > Hi All, >>> >> > I am trying to integrate my compass and accelerometer sensors >>> into >>> >> > android. >>> >> > These are two different sensors which support only providing >>> magnetic >>> >> > x, y, z and >>> >> > acceleration in x, y and z direction. As I gone through the >>> HAL layer >>> >> > of android I >>> >> > could know that android expects yaw, pitch, row also from the >>> under >>> >> > lying driver. >>> >> > I just wanted to conform this as the sensors we are using >>> does not >>> >> > give any values >>> >> > other than above mentioned. >>> >> > I would also like to know whether android does any >>> calibration on its >>> >> > own to get these >>> >> > values in case these are not supported by hardware. >>> >> > Please let me know if I need to provide more details regarding my >>> >> > sensors. >>> >> > >>> >> > >>> >> > -- >>> >> > Best Regards >>> >> > Pramod >>> >> > >>> >> > > >>> >> > >>> >> >>> >> >>> > >>> > >>> > > >>> > >>> >>> >>> >>> -- >>> Best Regards >>> Pramod >>> >>> >>> >>> >>> > >> >> >> > >> > > > > -- Best Regards Pramod --~--~---------~--~----~------------~-------~--~----~ unsubscribe: [email protected] website: http://groups.google.com/group/android-porting -~----------~----~----~----~------~----~------~--~---
