[paparazzi-commits] [paparazzi/paparazzi] a71054: Fix incorrect in-flight acceleration measurements ...

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/paparazzi/paparazzi
  Commit: a710548b6a8550690ed0642949bac7c576ebe0f0
      
https://github.com/paparazzi/paparazzi/commit/a710548b6a8550690ed0642949bac7c576ebe0f0
  Author: Tom van Dijk <address@hidden>
  Date:   2017-10-20 (Fri, 20 Oct 2017)

  Changed paths:
    M sw/simulator/nps/nps_fdm_gazebo.cpp

  Log Message:
  -----------
  Fix incorrect in-flight acceleration measurements in Gazebo (#2128)

* Fix Gazebo acceleration measurement

Gazebo's GetWorldLinearAccel() did not seem to take the ardrone's
velocity_decay into account, instead it measured the drone's
acceleration *without drag* which resulted in incorrect measurements
in-flight (the drone's acceleration in world frame did not go to
zero when the drone reached its steady-state velocity).

Fixed by manually deriving the drone's world velocity over time,
as in [Gazebo's own IMU 
implementation](https://bitbucket.org/osrf/gazebo/src/e26144434b932b4b6a760ddaa19cfcf9f1734748/gazebo/sensors/ImuSensor.cc?at=default&fileviewer=file-view-default#ImuSensor.cc-370).

Created an issue for Gazebo 
[here](https://bitbucket.org/osrf/gazebo/issues/2363/linear-velocity_decay-not-included-in-link).

* Remove unnecessary whitespace changes

* Make dt (nps_fdm_gazebo.cpp:338) double instead of float