Alignment of gyroscope readings to vehicle axis

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tim_pattinson
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Alignment of gyroscope readings to vehicle axis

Post by tim_pattinson » Fri Nov 02, 2018 11:57 am

Hi,

Let's assume I have a 6dof IMU and have corrected the accelerometer mounting from the readings at rest ( using g_correct_x() etc), and used track data to align the accelerometer X axis to the car's x axis.

Can i then use the same functions to rotate the gyro measurements into the same frame? (ie g_correct_x('gyro_x','gyro_y','gyro_z','gref_x','gref)y','gref_z','g_angle')

Or is there another way to do it?

regards
Tim

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RickS
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Re: Alignment of gyroscope readings to vehicle axis

Post by RickS » Mon Nov 05, 2018 9:38 am

You would need to contact a chassis dynamisist.
I'll ask if anybody here can answer your query and post any responses here.
BR, RickS

Ps. You might want to take a look at - philsal.co.uk/projects/imu-attitude-estimation - Possible what you might need but I have asked our developers to let me know if we can find anything else...

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RickS
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Re: Alignment of gyroscope readings to vehicle axis

Post by RickS » Tue Nov 06, 2018 8:27 am

I have done a little research on this overnight and have received the following information. I hope that it is of some assistance.. BR, RickS

Not 100% sure but it might actually work. See link below:-
https://electronics.stackexchange.com/q ... ence-frame
I think the construction of the matrix in the accepted answer there is equivalent to g_correct (though g_correct uses quaternions).

I guess just try it and see if it looks reasonable. You are going to have issues of drift on the gyros which this will not correct for.

tim_pattinson
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Re: Alignment of gyroscope readings to vehicle axis

Post by tim_pattinson » Sat Jan 19, 2019 7:42 am

Quick update for anyone else viewing:
Looks like it works. Need to double check once steering sensor is up and running, but the data looks sensible eg. Yaw velocity correlates with lat. accel

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RickS
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Re: Alignment of gyroscope readings to vehicle axis

Post by RickS » Mon Jan 28, 2019 11:14 am

Thank you for the reply and update.
Considered now closed

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