I'm going top build a high power model rocket and I'm wondering if I should use the BNO085 as the IMU. It has a pretty impressive profile and runs different firmware than the bno055, and I've heard the bno055 is kinda bad. So should I buy this sensor and use on a high power rocket? Or should I go with something like an ism330dlcx(another sensor I've been testing which I really like).
It depends on the demands You didn't tell.
What is the IMU supposed to do?
So my goal is to get accurate orientation data even under flight loads. Roll, pitch and yaw as well as quaternion rotation. I see that the bno085 does its own motion processing(which seems promising) and I'm wondering if that kind of firmware can handle flight loads on a high power rocket. If the bno085 isn't good for this purpose, is there another high-quality sensor I can use and then I can do my own sensor fusion from there?
Obtaining accurate orientation in a rocket is not possible with an IMU.
The IMU depends on the accelerometer to determine the down direction, assuming that the only acceleration is due to gravity. That fails in free fall or when the rocket is accelerating.
That's true about the accelerometer. I'm aware of when the rocket is accelerating and in free fall, orientation data using accelerometer data is worthless. So could I just us a gyroscope only? I'm aware of the gyro drift problem too... And that's what I'm wondering about the bno085. Is the motion processing on the chip good enough to account for problems such as high vibrations, acceleration and free fall? Gyro drift?
While the accelerometer says it is good for +/-8g, which might be just about enough for a High Power Rocket (check a flight simulator), the datasheet is full of application info for "tap sensing" on cell phones and navigation of cleaning robots. So rocketry seems a bit "out-of-scope."
It claims it'll report at least 100 samples/second (in "dumb uart mode"); is that approximately enough? It might do faster in the less dumb modes, but probably not 1000s/s, for example. (I dunno. I only scanned it.)
Try it and let us know. The model rocketry forums would be better places to ask.
Hm ok. Will do I'll try it out then.
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