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 [email protected]. To post to this group, send email to [email protected]. 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.
