Need help choosing IMU or compatable hardware.

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I need some help and guidance. I am designing a camera mount for my motorcycle that will tilt the camera in the opposite direction of my lean to keep the camera even with the horizon. I have been able to accomplish this on my bench using a 5DOF IMU but I’m hoping to be able to use cheaper IMU from sparkfun. Any ideas?

Also… since I haven’t been able to test it in a real world application yet, do you think the g-forces induced on the IMU during a corner will affect the calculated angle of lean?

Thanks in advance, Bill

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Bill2k:
… do you think the g-forces induced on the IMU during a corner will affect the calculated angle of lean?

W/o knowing your algorithms, hard to say. Simple usage of the accelerometer as a tilt sensor is guaranteed to fail. But IMUs are used to make AHRSs that do work.
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The algorithms I used were taken from http://www.tkjelectronics.com and https://github.com/TKJElectronics/KalmanFilter. I’m really just curious if you can calculate tilt on a single axis with a cheaper hardware, and what hardware that is.

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First I looked very quickly at the KF described at TJK. It seemed geared towards his balancing robot case. I didn’t follow his too simple (IMO) formulation for the system state. In any case you should be able to test the IMU by doing some simulated banked turns w/the IMU in your hand. Even if your bank and turn and translation of the IMU doesn’t match the physics of the bike, it doesn’t have to. Your head won’t rigidly follow your body in all turns either. You’ll still want the tilt compensation to work.

As for less complicated, I’d think a 3 axis magnetometer should be able to tell you tilt all by itself … in theory.