2.3.4 Sensors and filter
To keep track of the attitude, heading and position of the hexarotor an array
of sensors together with a software filter is needed. On the autopilot board all
the needed sensors are integrated except for the external gps-receiver. On the
secondary cpu a filter used to estimate heading and attitude of the hexarotor is
running. A compilation of the states, sensors and data processing can be seen in Table 2.1.