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kriswiner / EM7180_SENtral_sensor_hub

(Affordable) Ultimate Sensor Fusion Solution
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Quaternion data uses barometer data? #69

Open AllDigital33 opened 3 years ago

AllDigital33 commented 3 years ago

Hi Kris,

I am using the EM7180 on a model rocket to measure tilt and acceleration. I submitted an issue previously about the 10K foot altitude limitation in the barometer, due to the way the commercial version only uses one register.

I think I may be running into a related issue, but I'm not sure. I am using quat data to determine pitch/roll for tilt measurement, generated off of linear z. This works great, but when the rocket gets to about 14K feet linear z and roll values go haywire, but the raw x,y,z values seem to be fine. I assumed my rocket was in a tumble at high altitude, but I flew this weekend with another accelerometer and a camera and realized it was bad data coming off the EM7180.

Then I saw another (recent) issue indicating the quat filters required the baro to startup. Is it integrating the baro data into the quat data? That would explain my issue.

Thanks!!

kriswiner commented 3 years ago

I don't think the baro and accel are mixed in the stock EM7180 firmware, so I am not sure what would have happened here. Maybe Greg has an idea?

It is possible to correct the altitude limitation but this would take some work on Greg's part and I expect he would want to get paid for it; he is the firmware developer for this device.

On Mon, Dec 7, 2020 at 7:35 PM AllDigital33 notifications@github.com wrote:

Hi Kris,

I am using the EM7180 on a model rocket to measure tilt and acceleration. I submitted an issue previously about the 10K foot altitude limitation in the barometer, due to the way the commercial version only uses one register.

I think I may be running into a related issue, but I'm not sure. I am using quat data to determine pitch/roll for tilt measurement, generated off of linear z. This works great, but when the rocket gets to about 14K feet linear z and roll values go haywire, but the raw x,y,z values seem to be fine. I assumed my rocket was in a tumble at high altitude, but I flew this weekend with another accelerometer and a camera and realized it was bad data coming off the EM7180.

Then I saw another (recent) issue indicating the quat filters required the baro to startup. Is it integrating the baro data into the quat data? That would explain my issue.

Thanks!!

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