The function quat_from_euler_xyz in math.py seems error

[zxytql]

IsaacLab/source/isaaclab/isaaclab/utils/math.py

Lines 271 to 297 in 7006bb7

	def quat_from_euler_xyz(roll: torch.Tensor, pitch: torch.Tensor, yaw: torch.Tensor) -> torch.Tensor:
	"""Convert rotations given as Euler angles in radians to Quaternions.
	Note:
	The euler angles are assumed in XYZ convention.
	Args:
	roll: Rotation around x-axis (in radians). Shape is (N,).
	pitch: Rotation around y-axis (in radians). Shape is (N,).
	yaw: Rotation around z-axis (in radians). Shape is (N,).
	Returns:
	The quaternion in (w, x, y, z). Shape is (N, 4).
	"""
	cy = torch.cos(yaw * 0.5)
	sy = torch.sin(yaw * 0.5)
	cr = torch.cos(roll * 0.5)
	sr = torch.sin(roll * 0.5)
	cp = torch.cos(pitch * 0.5)
	sp = torch.sin(pitch * 0.5)
	# compute quaternion
	qw = cy * cr * cp + sy * sr * sp
	qx = cy * sr * cp - sy * cr * sp
	qy = cy * cr * sp + sy * sr * cp
	qz = sy * cr * cp - cy * sr * sp
	return torch.stack([qw, qx, qy, qz], dim=-1)

I check the wikipedia, the conversation method is the same as 3-2-1 sequence. So the function name shoule be quat_from_euler_zyx?

[PeterL-NV]

I think the naming quat_from_euler_xyz is correct. Please see the note,

Note: 
         The euler angles are assumed in XYZ convention. 

And the input is roll (x), pitch (y), yaw (z)

[zxytql]

Oh! Does this function refer to XYZ extrinsic rotation? I'm really stunned by this :(

As I know. XYZ extrinsic rotation is equal to ZYX intrinsic rotation.