Modules Reference: Estimator 
AttitudeEstimatorQ 
Source: modules/attitude_estimator_q
Description 
Attitude estimator q.
Usage 
AttitudeEstimatorQ <command> [arguments...]
 Commands:
   start
   stop
   status        print status infoairspeed_estimator 
Source: modules/airspeed_selector
Description 
This module provides a single airspeed_validated topic, containing indicated (IAS), calibrated (CAS), true airspeed (TAS) and the information if the estimation currently is invalid and if based sensor readings or on groundspeed minus windspeed. Supporting the input of multiple "raw" airspeed inputs, this module automatically switches to a valid sensor in case of failure detection. For failure detection as well as for the estimation of a scale factor from IAS to CAS, it runs several wind estimators and also publishes those.
Usage 
airspeed_estimator <command> [arguments...]
 Commands:
   start
   stop
   status        print status infoekf2 
Source: modules/ekf2
Description 
Attitude and position estimator using an Extended Kalman Filter. It is used for Multirotors and Fixed-Wing.
The documentation can be found on the ECL/EKF Overview & Tuning page.
ekf2 can be started in replay mode (-r): in this mode, it does not access the system time, but only uses the timestamps from the sensor topics.
Usage 
ekf2 <command> [arguments...]
 Commands:
   start
     [-r]        Enable replay mode
   stop
   status        print status info
     [-v]        verbose (print all states and full covariance matrix)
   select_instance Request switch to new estimator instance
     <instance>  Specify desired estimator instancelocal_position_estimator 
Source: modules/local_position_estimator
Description 
Attitude and position estimator using an Extended Kalman Filter.
Usage 
local_position_estimator <command> [arguments...]
 Commands:
   start
   stop
   status        print status infomc_hover_thrust_estimator 
Source: modules/mc_hover_thrust_estimator
Description 
Usage 
mc_hover_thrust_estimator <command> [arguments...]
 Commands:
   start
   stop
   status        print status info