RSpincalc (version 1.0.2)

EA2EV: Convert from Euler Angles to Euler Vectors

Description

EA2EV converts from Euler Angles (EA) to Euler Vectors (EV).

Usage

EA2EV(EA, EulerOrder='zyx', tol = 10 * .Machine$double.eps, ichk = FALSE, 
ignoreAllChk = FALSE)

Arguments

EA

Euler Angles (EA) vector [psi, theta, phi].

EulerOrder

Euler Order (xyx, yzy, zxz, xzx, yxy, zyz, xyz, yzx, zxy, xzy, yxz, zyx)

tol

Tolerance from deviations from unity for the determinant of rotation matrices or the the vector length for unitary vectors.

ichk

Logical, FALSE=disables near-singularity warnings.

ignoreAllChk

Logical, TRUE=disables all warnings and error checks (use with caution!).

Value

Euler Vectors (EV) vector [m1, m2, m3, MU].

Details

Euler Angles (EA) xyz <=> x(roll) y(pitch) z(yaw) Type 1 Rotations (Tait-Bryan angles): xyz - xzy - yxz - yzx - zyx - zxy Singular if second rotation angle is -90 or 90 degrees. Type 2 Rotations (proper Euler angles): xyx - xzx - yxy - yzy - zxz - zyz Singular if second rotation angle is 0 or 180 degrees.

Euler angles [psi, theta, phi] range from -90 to 90 degrees. Tait-Bryan angles [psi, theta, phi] range from 0 to 180 degrees. Angles about Euler vectors range from 0 to 180 degrees.

References

by John Fuller, 14 Jul 2008 SpinCalc, Function to Convert between DCM, Euler angles, Quaternions, and Euler vectors. http://www.mathworks.com/matlabcentral/fileexchange/20696-function-to-convert-between-dcm--euler-angles--quaternions--and-euler-vectors

Paolo de Leva, 01 May 2013 SpinConv, Conversion from a rotation representation type to another. http://www.mathworks.com/matlabcentral/fileexchange/41562-spinconv

See Also

EV2EA

Examples

EAxyx <- c(-170.6607, 110.937, 136.2344) * (pi/180)
EA2EV(EAxyx,'xyx')