navlie.lib.models.AbsoluteVelocity¶

class navlie.lib.models.AbsoluteVelocity(R: ndarray)¶

World-frame, or “absolute” velocity measurement. This model is of the form

\[\mathbf{y} = \mathbf{v}\]

where \(\mathbf{v}\) is the velocity of the robot.

Compatible with SE23State, IMUState

evaluate(x: MatrixLieGroupState)¶: Evaluates the measurement model \(\mathbf{g}(\mathcal{X})\).

jacobian(x: MatrixLieGroupState)¶: Evaluates the measurement model Jacobian with respect to the state.

\[\mathbf{G} = \frac{D \mathbf{g}(\mathcal{X})}{D \mathcal{X}}\]

covariance(x: MatrixLieGroupState) → ndarray¶: Returns the covariance \(\mathbf{R}\) associated with additive Gaussian noise.

evaluate_with_jacobian(x: State) → Tuple[ndarray, ndarray]¶: Evaluates the measurement model and simultaneously returns the Jacobian as its second output argument. This is useful to override for performance reasons when the model evaluation and Jacobian have a lot of common calculations, and it is more efficient to calculate them in the same function call.

jacobian_fd(x: State, step_size=1e-06)¶: Calculates the model jacobian with finite difference.

navlie.lib.models.AbsolutePosition

navlie.lib.models.Altitude