Mikhail Grushinskiy

> > Actually after reading more in the subject, wave surface is actually the surface of equal pressure. So basically barometer is useless for measuring wave height. It will pick...

I’ve implemented Kalman filter to integrate acceleration into wave height with drift correction for integration with noise in input. Here is the code. It also draws plots. https://github.com/bareboat-necessities/wave_height_from_IMU/blob/main/wave_height_from_IMU.py

> What is Kalyan? It's a typo. Kalman

> I will study it. I have also previously implemented a kalman filter to blend gps with inertial sensors. It provides high rate position and speed estimation and gives a...

Now that it's possible to evaluate vertical velocity it would be interesting to compare how pitch follows it. Pitch is measured by gyro and magnetometer I'd guess and vertical velocity...

Also few observations on algorithm behavior. If mean(Acceleration) != 0 (you have constant noise offset) It's going to underestimate wave height. It's going to flatten it on one of the...

I propose adding these NMEA sentences. They can be allowed optionally as Kalman filter option too. ``` $APXDR,A,-0.087,M,VDIS* $APXDR,A,0.08,,VVEL* $APXDR,A,-0.087,,VACC* $APMWH,3.44,f,1.05,M* VDIS - vertical displacement (m) VVEL - vertical velocity...

@seandepagnier > I think the same kalman filter can do both and would be less processing power. Once it is all working and proven it can also be used by...

``` wind.offset=0.0000 wind.sensors_height=15.0000 gps.filtered.enabled=false nmea.client="" nmea.gps_id="APRMC" imu.rate=20 imu.alignmentQ=[0.08716496318642837, 0.01992134620873801, 0.9959874124562726, 0.003805704481305205] imu.heading_offset=5.0000 rudder.offset=0.0 rudder.scale=100.0 rudder.nonlinearity=0.0 rudder.range=45.0000 apb.xte.gain=300.0000 servo.faults=0 servo.max_current=4.5000 servo.current.factor=1.0000 servo.current.offset=0.0000 servo.voltage.factor=1.0000 servo.voltage.offset=0.0000 servo.max_controller_temp=60.0000 servo.max_motor_temp=60.0000 servo.max_slew_speed=28.0000 servo.max_slew_slow=34.0000 servo.gain=1.0000 servo.clutch_pwm=100.0000 servo.use_brake=false...

ALso locking compass calibration seems has no effect. It still comes back as unlocked.