rigid_body_motion.ReferenceFrame.lookup_angular_velocity

ReferenceFrame.lookup_angular_velocity(reference=None, represent_in=None, outlier_thresh=None, cutoff=None, mode='quaternion', allow_static=False, return_timestamps=False)

Estimate angular velocity of this frame wrt a reference.

Parameters

reference: str or ReferenceFrame, optional

The reference frame wrt which the twist is estimated. Defaults to the parent frame.

represent_in: str or ReferenceFrame, optional

The reference frame in which the twist is represented. Defaults to the parent frame.

outlier_thresh: float, optional

Suppress samples where the norm of the second-order differences of the rotation is above outlier_thresh and interpolate the missing values.

cutoff: float, optional

Frequency of a low-pass filter applied to linear and angular velocity after the estimation as a fraction of the Nyquist frequency.

mode: str, default “quaternion”

If “quaternion”, compute the angular velocity from the quaternion derivative. If “rotation_vector”, compute the angular velocity from the gradient of the axis-angle representation of the rotations.

allow_static: bool, default False

If True, return a zero velocity vector and None for timestamps if the transform between this frame and the reference frame is static. Otherwise, a ValueError will be raised.

return_timestamps: bool, default False

If True, also return the timestamps of the lookup.

Returns

angular: numpy.ndarray, shape (N, 3)

Angular velocity of moving frame wrt reference frame, represented in representation frame.

timestamps: each numpy.ndarray

Timestamps of the angular velocity.