BHI360 step counter

[JAS]

Hi,

I have created a custom PCB using the BHI360 and the BMM350.

I am trying to use the IMU as a step counter, however, it does not seem to be very accurate.  Using the device as a wearable, it seems to register between 30-50% of the steps I take. I am currently using the low power step counter - BHY2_SENSOR_ID_STC_LP,  id 136.,

Is there any method to trouble shoot the step counter algorithm, or adjust its sensitivity?

I saw the data sheet contains references to Activity Parameters and to adjusting sensitivity and dynamic range, but I do  not understand how to use these commands or if they are relevant. 

[BSTRobin]

Hi JAS,

Could we know from you:
What is ODR you used as BHI360 used in wearable device? And what is your test case and detailed test result?
Yes, "13.3.7 physical sensor control parameters(0x0E00 - 0x0EFF" mentioned some parameters can be modified, but not contain step counter.

[JAS]

Hi @BSTRobin ,

Thank you for the response.

The test case was strapping custom hardware containing the BHI360 to my chest, walking around and manually counting my steps. I noticed that over many tests it seemed to reliably measure 50% of my manual steps, +/-10%. (e.g. 24-27 steps when I walked 50steps, 49-54 steps when I walked 100 steps, and 250 steps when I walked 500). Is this by design? Does the step counter only count a "step" when you do both a 'left' and a 'right' foot step?

Is the ODR simply the sampling frequency of the virtual sensor? I have sampling frequency set to 1Hz. I ran the get parameter command for the Low Power Step Counter Virtual Sensor (0x0300 + BHY2_SENSOR_ID_STC_LP = 0x0388) and it returned 0x88F90100010010000000803F00000000660C0000050000803F000000. Looking at byte 0x0C-0x0F and 0x19-0x1C (bolded), it comes up as 0x3F800000 which is 1 as a float. I got this information from section 13.3.4/Table70 of the data sheet. 

Looking forward to hearing your reply. 

[JAS]

Hi @BSTRobin , just following up on this point - do you have any further advice?