IMU: Fixed ICM42688 "stuck" gyro issue #25332
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these undocumented bits in register 0x4d control the "adaptive full scale range" mode of the ICM42688. The feature is enabled by default but has a bug where it gives "stuck" gyro values for short periods (between 1ms and 2ms):, leading to a significant gyro bias at longer time scales, enough to in some cases cause a vehicle to crash if it is unable to switch to an alternative IMU this fixes ArduPilot#25025
…river this is useful for tracking down and confirming the stuck gyro issue on the ICM42688
andyp1per
approved these changes
Oct 21, 2023
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Whew! |
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Thanks for figuring this out guys. PR now raised for Betaflight. betaflight/betaflight#13132 |
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This fixes issue #25025
the ICM42688 has an "AFSR" feature (enabled by default) where it switches between a low-noise mode at angular rates below 100 deg/sec and a higher noise mode above that level. When it switches it causes the gyro to become "stuck" for between 1ms and 2ms, leading to a significant gyro bias that can under some circumstances lead to a crash of the vehicle if it is not able to switch to another IMU.
This PR does 2 things: