I'd suggest two things, (1) Read the Android source code eg: https://source.android.com/devices/halref/sensors_8h_source.html + CTS eg http://static.googleusercontent.com/media/source.android.com/en//compatibility/android-cdd.pdf (2) Answer your own questions by writing a test app to measure the data yourself, being sure to run it on several different devices.
On Tuesday, June 7, 2016 at 3:31:59 AM UTC+10, Ahmed Ibrahim wrote: > > I was asking about some details in capturing data from smartphone > accelerometer. I am using Samsung S5, which has the invensense MPU6500 > 6-axis chip. The datasheet of the chip indicates a lot of sampling > rate/bandwidth options. However, through android we only have few options > concerning the sensor delay: SENSOR_DELAY_FASTEST, SENSOR_DELAY_GAME, > SENSOR_DELAY_NORMAL and SENSOR_DELAY_UI. > > > I need to know two things: 1) the sampling rate accuracy and 2) the > bandwidth. > > > What I concluded so far is that the sampling rate for certain setting is > not exactly fixed, it is fluctuating around certain number, for example the > fastest setting nominal sampling rate is 200Hz, but the sampling time will > be 4~6 msec. The sensor provides time stamp with each sample with 1msec > resolution. > > > My questions are: > > 1) How far the timestamp is accurate, or in other words how much error I > need to assume in the sample timing? > > 2) What are the associated bandwidth with each SENSOR_DELAY setting? > because according to the chip datasheet, the bandwidth is not related to > the sampling rate. The bandwidth will be known if we can get how android > program the sensor chip with each of delay settings. > > > Thanks :) > -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To unsubscribe from this group and stop receiving emails from it, send an email to android-developers+unsubscr...@googlegroups.com. To post to this group, send email to android-developers@googlegroups.com. Visit this group at https://groups.google.com/group/android-developers. To view this discussion on the web visit https://groups.google.com/d/msgid/android-developers/bc501c0b-e198-442a-949f-d6fbbd6df465%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
