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    BNO055 Sensor behavior with horizontal rotation

    BNO055 Sensor behavior with horizontal rotation

    Established Member

    Hi Everyone,

    1. As we are a product based company, We purchased BNO055 Sensor Dev kit for our development, and we are evaluating it for our requirement.
    We found an observation that, when the sensor is an horizontal rotation(say 90 degree in heading ) and if usb dev kit is unplugged and plugged, and opening Bosch Development Desktop UI again means, we are getting 0 degree in heading information when we are in relative and absolute modes (IMU plus and NDOF )
    2. As per datasheet, it should have some difference in it's heading information, but we didnt see any difference in both the modes. and seeing only 0 degree after power on, even if it is already in 90 degree position.

    So please provide your support to overcome this issue.

    Thanks in Advance,
    Uma Maheswari.G

    19 REPLIES 19

    Established Member


    Good Morning.,

    As we discussed earlier, below image is our requirement.

    Our product will be rotating horizontally as shown in the diagram below.,


    For this rotation, we want a mode which should retain the heading values, even after battery off and on again.

    And also we are checking for the modes which consumes less power i.e suspend mode

    We will put the sensor in suspend mode, and whenever there is a need we will wake up the sensor and collect the data.

    To do this, we are following below steps.,

    1. Put sensor in sleep mode

    2. To wake up the sensor for data collection, as you suggest we need to enter into config mode to make it to normal mode and collect the data, so we are doing soft reset and configuring it to IMU or NDOF mode and collecting the data.

    3. Here we are getting zero heading(horizontal) data in both IMU or NDOF modes, even our product is rotated horizontally to 90 degree.

    We want modes to retain the data even after power on reset and it should not show 0 degree.

    Please help us to proceed further.

    Your inputs on this will be highly appreciated.

    Thanks & Regards,

    Uma Maheswari.G

    Occasional Contributor

    Hi Sir:

         According to your idea, maybe you should choose NDOF mode, which output the absolute orientation.

        After power off and on again, if all accuracy is 3 and sensor is not moved,  the output angle will be the same value with the last value.

        So you should save the calibration profile before power off or after a full calibration is achieved and after next power on, write them to the sensor.

        Please see the 3.11.4 Reuse of Calibration Profile of BNO055 datasheet to know how to do.


    Established Member


    Thanks for the reply. we are working in this.

    As you suggested, we tried with NDOF mode. so after on power on reset i got some data in the heading field, but it is not same as the heading data before software reset. so there could be some issues like where i need to store the calibration profile and when it needs to be applied in sensor.

    Here is the operation we need.,

    1. i will make the sensor in suspend mode,

    2. after a period, i will give soft reset,and make the sensor into config mode 

    3. and put the sensor in NDOF operation mode, collect the data

    4. again do soft reset and put the sensor in suspend mode

    this is what our requirement.

    we have below questions now.,

    1. When we need to check the calibration status register and what are all the things to be verified in getting 3 (Acclero,gyro and magneto alone or i should get system also i,e i should get 0xFF in that calibration status register?)
    2. when i need to check the calibration status and store the calibration profile ? in Suspend mode or in after putting into NDOF mode (Bcoz in data sheet,they mentioned calibration profile should be taken after calibration and in config mode)

    3. When i need to write this calibration profile into the sensor as per my requirement.

    So please provide us more details to use the solution provided by you.

    Thanks & Regards,
    Uma Maheswari.G

    Occasional Contributor

    Hi Sir:

         Please see my following comments:

        1. Regarding saving the calibration profile, after all accuuray are 3, you can save them. Maybe you need to save many times because of magnetic field change and gyroscope.

        2. Regarding loading the calibration profile, after change power mode to normal mode before enable fusion mode, you should do it.

        3.  You need to check the calibration status and store the calibration profile when you want to use fusion sensor data. Ensure all accuarcy are 3, or you will need to calibrte them.



    Established Member

    Thankyou jet for your quick responses. it was really useful for our further evaluations.

    from your reply and our analysis, we are able to understand that, 
    1. Sensor data's can be retained, only if the sensor is not moved

    2. If the sensor is moved after profile save and before profile apply, you will not be retaining the data and showing 0.

    3. For each and every angle change, we wants to store calibration profile before power on reset. but it is possible only after full calibration.
    i,e, CALIB_STAT_REG should have  0xFF value.

    4. Full calibration means each sensor should be calibrated in it's way mentioned in the datasheet.

    Now we have a problem with this sensor in our product is,

    1. We can not move the sensor to different positions as you mentioned for calibration to store calibration profile for each angle change ,once we installed in our product.
    2. Because all are high current equipments, above that only we will be placing this sensor part.
    3. We want low power consumption in idle, when we wakeup the sensor should retain the heading data(horizontal) with the angle changed and also we can not calibrate or move the sensor each and every time.
    Is it possible with BNO055 NDOF mode or is there any other sensors available with you.

    Please clarify.

    Thanks & Regards,
    Uma Maheswari.G