All of the sensor data used by Ranger NBV is subject to noise and
bias. These inaccuracies in the reported data leads to errors in the
estimate of the vehicle attitude and angular velocity. The flight
control interface provides a means for controlling the bias
estimation, and parameters of the filters and other noise reduction
methods to be described below.
Figure 3-3 Bias Estimator Enable
Currently, bias estimation algorithms have been implemented for
the angular rate sensor and the magnetometer. These algorithms are
described in detail in Section 4.3.2.
Sensor noise degrades the performance of vehicle state estimation and control. The interface provides a means for adjusting some of the parameters that control algorithms that help to reduce the impact of noise on system performance.
Figure 3-4 Noise Reduction Parameter Control
The first parameter G, helps to reduce the effect of sensor noise
on the nonlinear controller. This is discussed in detail in Section
The next two parameters control the filtering of the attitude and angular velocity estimates. These methods are discussed in Section 4.3.1.