BMM150 and BMI088 on a glider

[sethc333]

Hey guys,

I am designing an absolute orientation sensor suite to track my glider's orientation. I do fly some loops and hard turns, but much of my time is spent spiraling up thermals. I'm currently looking at using a BMI088 with a BMM150 and would like to understand how the sensor readings might drift over multi-hour flights.

Does the BMM150 require a stationary orientation in order to accurately measure its orientation? If so, how long does it take to reorient itself once the plane is maintaining a constant orientation? 

If not, what are its limitations? How fast can the glider turn before the magnetometer loses its bearings? And, once again, how fast does the magnetometer reorient itself and does the glider need to maintain a constant orientation for it to do so?

I understand that the BMI088 will support the BMM150 through the fusion software, but I need it to track this glider for multiple hours of uninterrupted flight, with as little  hassle as possible. I figured that this is best sensor combination for this application, but I am no expert.

Thank you for you insights!

[FAE_CA1 · Accepted solution]

Hi,

Yes, it is true that BMI088 + BMI150 is better for applications like drones and robots because the gyro inside BMI088 is close-loop gyro and the accel inside BMI088 has vibration damping feature. This is only based on the situation if you have your own sensor fusion algorithm handy. For example, you can download BSXLite from Bosch website or search for other open-source sensor fusion algorithms.

Otherwise, I would like to recommend BHI260AP + BMM150 to you.

Thanks.

[sethc333]

Great, I probably will go with the BMI088 and the BMM150, with the BSXLite algorithm. If it does not work out, perhaps I will try your other recommendation. Thanks again.

[b0lero]

Hello there, I am also considering using BMI088 and BMM150 on a custom PCB with ESP32 and I was wondering about the alignment of both ICs. Do they have to be in the exact alignment? My current PCB layout looks like this:

U3 - BMM150 - DOT ON TOP RIGHT CORNER

U2 - BMI088 - DOT ON BOTTOM LEFT CORNER!

U4 BMP581 - Barometer - It doesn't matter how it is mounted.

U3 - BMM150 - U2 - BMI088 - U4 BMP581

[FAE_CA1]

Hi,

Your PCB layout looks fine. It doesn't matter if U2-BMI088 and U3-BMM150 are on the different layers of the PCB as long as their x/y/z axes are parallel. After the PCB is mounted inside an enclosure, U2 and U3 x/y/z axes will be invisible. You only know the enclosure X/Y/Z axes. So you just need to map U2 and U3 x/y/z axes to the enclosure X/Y/Z axes and then feed remapped X/Y/Z data into BSXLite.

Please refer to the attached PDF file for more information.

Thanks.

[b0lero]

Thank You for your reply 🙂

Does Bosch plan to implement BSX 3.0 full fusion like on the BNO055, and where can we find documentation on how to do it ourselves?

Thanks again!