"refer to Louis, (1-based indexing)
phi = atan2(-DCM23, DCM33)
theta = atan2(DCM13, sqrt(1-(DCM13)^2))
psi=atan2( -DCM12, DCM11)

and the firmware on ArduIMU_pack,
theta=asin(DCM[3,1])

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the angle of phi & psi is varied from 0 to 180 then -180 to…"

"can anyone explain me how equation 14 became a matrix form in equation 17 ? (refer to DCMDraft2.pdf)

i don't understand how "r(t) + r(t) x d0(t)" there's an addition and a cross product became matrix multiplication by a scalar in equation 17..

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