I listened to this talk: http://www.youtube.com/watch?v=C7JQ7Rpwn2k
which is Invensense Inc prototyping their "Sensor fusion" system, which is where they combine gyro, accelerometer, compass measurements in Android, to get better results.
Is this currently implemented in any version of Android? The reason I ask is, part of sensor fusion is the "Gravity" sensor and the "Linear Acceleration" sensor, which ARE implemented in Android ever since API Level 9... makes me think that either 1) sensor fusion is implemented 2) sensor fusion is not implemented, but these are just added into Android API in anticipation of widespread added sensorfusion implementation in the future.
Does anyone know?
Thanks
Have a look at the first answer to this question. There you will find the explanation of the different types of sensors, directly from one of the Google developers working on these topics. For your information, gyroscope sensor is not included in any of the new "fused" sensors.
There is no such thing as a 'gravity' sensor (ignoring the search for gravity waves!). Gravity IS an acceleration and hence is detected by the linear accelerometer as well as any other acceleration the sensor may be subject.
来源：https://stackoverflow.com/questions/7776034/sensor-fusion-implemented-on-android