def integrate(dt, phase, orientation):
    """ Integrate motion to produce new orientation """
    phase += 2*pi*dt*Omegaf
    omega = Omega*cos(phase)
    delta = (np.eye(3), rotations.hat_map(dt*omega))
    orientation = SO3.multiply(orientation, SO3.expmap(delta))
    return phase, omega, orientation
def accelerometer(orientation):
    """ Produce gravity vector from orientation matrix """
    acceleration = SO3.multiply(SO3.inverse(orientation), Gravity)
    return acceleration